From 3640ff4263c7323d77036cf5eeedf60855d177f5 Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 14:30:20 +0100 Subject: [PATCH 01/89] Don't recheck inherited trait parameters during capture checking The logic gets refused by the added capture refinements. --- compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala | 2 ++ compiler/src/dotty/tools/dotc/typer/RefChecks.scala | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index fab0689b4df2..ad216c47d2f5 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -1122,6 +1122,8 @@ class CheckCaptures extends Recheck, SymTransformer: override def needsCheck(overriding: Symbol, overridden: Symbol)(using Context): Boolean = !setup.isPreCC(overriding) && !setup.isPreCC(overridden) + + override def checkInheritedTraitParameters: Boolean = false end OverridingPairsCheckerCC def traverse(t: Tree)(using Context) = diff --git a/compiler/src/dotty/tools/dotc/typer/RefChecks.scala b/compiler/src/dotty/tools/dotc/typer/RefChecks.scala index eef88e76971e..af279844f370 100644 --- a/compiler/src/dotty/tools/dotc/typer/RefChecks.scala +++ b/compiler/src/dotty/tools/dotc/typer/RefChecks.scala @@ -267,6 +267,9 @@ object RefChecks { if !other.is(Deferred) then checkOverride(subtypeChecker, dcl, other) end checkAll + + // Disabled for capture checking since traits can get different parameter refinements + def checkInheritedTraitParameters: Boolean = true end OverridingPairsChecker /** 1. Check all members of class `clazz` for overriding conditions. @@ -851,7 +854,7 @@ object RefChecks { checkCaseClassInheritanceInvariant() } - if (!clazz.is(Trait)) { + if (!clazz.is(Trait) && checker.checkInheritedTraitParameters) { // check that parameterized base classes and traits are typed in the same way as from the superclass // I.e. say we have // From b65fd3a4435f450f69c4e21b521c185f6b3f3e6c Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 14:31:11 +0100 Subject: [PATCH 02/89] Add SeqView to stdlib --- tests/pos-special/stdlib/collection/Seq.scala | 4 +- .../stdlib/collection/SeqView.scala | 231 ++++++++++++++++++ 2 files changed, 233 insertions(+), 2 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/SeqView.scala diff --git a/tests/pos-special/stdlib/collection/Seq.scala b/tests/pos-special/stdlib/collection/Seq.scala index caabf6fa6436..81f39b3538cf 100644 --- a/tests/pos-special/stdlib/collection/Seq.scala +++ b/tests/pos-special/stdlib/collection/Seq.scala @@ -77,7 +77,7 @@ object Seq extends SeqFactory.Delegate[Seq](immutable.Seq) * @define coll sequence * @define Coll `Seq` */ -trait SeqOps[+A, +CC[_], +C] extends Any with IterableOps[A, CC, C] { self => +trait SeqOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { self => override def view: SeqView[A] = new SeqView.Id[A](this) @@ -234,7 +234,7 @@ trait SeqOps[+A, +CC[_], +C] extends Any with IterableOps[A, CC, C] { self => * * @return an iterator yielding the elements of this $coll in reversed order */ - def reverseIterator: Iterator[A] = reversed.iterator + override def reverseIterator: Iterator[A] = reversed.iterator /** Tests whether this $coll contains the given sequence at a given index. * diff --git a/tests/pos-special/stdlib/collection/SeqView.scala b/tests/pos-special/stdlib/collection/SeqView.scala new file mode 100644 index 000000000000..f8f4f1e199de --- /dev/null +++ b/tests/pos-special/stdlib/collection/SeqView.scala @@ -0,0 +1,231 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.annotation.nowarn +import language.experimental.captureChecking +import caps.unsafe.unsafeAssumePure + +/** !!! Scala 2 difference: Need intermediate trait SeqViewOps to collect the + * necessary functionality over which SeqViews are defined, and at the same + * time allowing impure operations. Scala 2 uses SeqOps here, but SeqOps is + * pure, whereas SeqViews are Iterables which can be impure (for instance, + * mapping a SeqView with an impure function gives an impure view). + */ +trait SeqViewOps[+A, +CC[_], +C] extends Any with IterableOps[A, CC, C] { + self: SeqViewOps[A, CC, C]^ => + + def length: Int + def apply(x: Int): A + def appended[B >: A](elem: B): CC[B]^{this} + def prepended[B >: A](elem: B): CC[B]^{this} + def reverse: C^{this} + def sorted[B >: A](implicit ord: Ordering[B]): C^{this} + + def reverseIterator: Iterator[A]^{this} = reversed.iterator +} + +trait SeqView[+A] extends SeqViewOps[A, View, View[A]] with View[A] { + self: SeqView[A]^ => + + override def view: SeqView[A]^{this} = this + + override def map[B](f: A => B): SeqView[B]^{this, f} = new SeqView.Map(this, f) + override def appended[B >: A](elem: B): SeqView[B]^{this} = new SeqView.Appended(this, elem) + override def prepended[B >: A](elem: B): SeqView[B]^{this} = new SeqView.Prepended(elem, this) + override def reverse: SeqView[A]^{this} = new SeqView.Reverse(this) + override def take(n: Int): SeqView[A]^{this} = new SeqView.Take(this, n) + override def drop(n: Int): SeqView[A]^{this} = new SeqView.Drop(this, n) + override def takeRight(n: Int): SeqView[A]^{this} = new SeqView.TakeRight(this, n) + override def dropRight(n: Int): SeqView[A]^{this} = new SeqView.DropRight(this, n) + override def tapEach[U](f: A => U): SeqView[A]^{this, f} = new SeqView.Map(this, { (a: A) => f(a); a }) + + def concat[B >: A](suffix: SeqView.SomeSeqOps[B]): SeqView[B]^{this} = new SeqView.Concat(this, suffix) + def appendedAll[B >: A](suffix: SeqView.SomeSeqOps[B]): SeqView[B]^{this} = new SeqView.Concat(this, suffix) + def prependedAll[B >: A](prefix: SeqView.SomeSeqOps[B]): SeqView[B]^{this} = new SeqView.Concat(prefix, this) + + override def sorted[B >: A](implicit ord: Ordering[B]): SeqView[A]^{this} = new SeqView.Sorted(this, ord) + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "SeqView" +} + +object SeqView { + + /** A `SeqOps` whose collection type and collection type constructor are unknown */ + private type SomeSeqOps[+A] = SeqViewOps[A, AnyConstr, _] + + /** A view that doesn’t apply any transformation to an underlying sequence */ + @SerialVersionUID(3L) + class Id[+A](underlying: SomeSeqOps[A]^) extends AbstractSeqView[A] { + def apply(idx: Int): A = underlying.apply(idx) + def length: Int = underlying.length + def iterator: Iterator[A]^{this} = underlying.iterator + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + @SerialVersionUID(3L) + class Map[+A, +B](underlying: SomeSeqOps[A]^, f: A => B) extends View.Map[A, B](underlying, f) with SeqView[B] { + def apply(idx: Int): B = f(underlying(idx)) + def length: Int = underlying.length + } + + @SerialVersionUID(3L) + class Appended[+A](underlying: SomeSeqOps[A]^, elem: A) extends View.Appended(underlying, elem) with SeqView[A] { + def apply(idx: Int): A = if (idx == underlying.length) elem else underlying(idx) + def length: Int = underlying.length + 1 + } + + @SerialVersionUID(3L) + class Prepended[+A](elem: A, underlying: SomeSeqOps[A]^) extends View.Prepended(elem, underlying) with SeqView[A] { + def apply(idx: Int): A = if (idx == 0) elem else underlying(idx - 1) + def length: Int = underlying.length + 1 + } + + @SerialVersionUID(3L) + class Concat[A](prefix: SomeSeqOps[A]^, suffix: SomeSeqOps[A]^) extends View.Concat[A](prefix, suffix) with SeqView[A] { + def apply(idx: Int): A = { + val l = prefix.length + if (idx < l) prefix(idx) else suffix(idx - l) + } + def length: Int = prefix.length + suffix.length + } + + @SerialVersionUID(3L) + class Reverse[A](underlying: SomeSeqOps[A]^) extends AbstractSeqView[A] { + def apply(i: Int) = underlying.apply(size - 1 - i) + def length = underlying.size + def iterator: Iterator[A]^{this} = underlying.reverseIterator + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + @SerialVersionUID(3L) + class Take[+A](underlying: SomeSeqOps[A]^, n: Int) extends View.Take(underlying, n) with SeqView[A] { + def apply(idx: Int): A = if (idx < n) { + underlying(idx) + } else { + throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${if (underlying.knownSize >= 0) knownSize - 1 else "unknown"})") + } + def length: Int = underlying.length min normN + } + + @SerialVersionUID(3L) + class TakeRight[+A](underlying: SomeSeqOps[A]^, n: Int) extends View.TakeRight(underlying, n) with SeqView[A] { + private[this] val delta = (underlying.size - (n max 0)) max 0 + def length = underlying.size - delta + @throws[IndexOutOfBoundsException] + def apply(i: Int) = underlying.apply(i + delta) + } + + @SerialVersionUID(3L) + class Drop[A](underlying: SomeSeqOps[A]^, n: Int) extends View.Drop[A](underlying, n) with SeqView[A] { + def length = (underlying.size - normN) max 0 + @throws[IndexOutOfBoundsException] + def apply(i: Int) = underlying.apply(i + normN) + override def drop(n: Int): SeqView[A]^{this} = new Drop(underlying, this.n + n) + } + + @SerialVersionUID(3L) + class DropRight[A](underlying: SomeSeqOps[A]^, n: Int) extends View.DropRight[A](underlying, n) with SeqView[A] { + private[this] val len = (underlying.size - (n max 0)) max 0 + def length = len + @throws[IndexOutOfBoundsException] + def apply(i: Int) = underlying.apply(i) + } + + @SerialVersionUID(3L) + class Sorted[A, B >: A] private (private[this] var underlying: SomeSeqOps[A]^, + private[this] val len: Int, + ord: Ordering[B]) + extends SeqView[A] { + outer: Sorted[A, B]^ => + + // force evaluation immediately by calling `length` so infinite collections + // hang on `sorted`/`sortWith`/`sortBy` rather than on arbitrary method calls + def this(underlying: SomeSeqOps[A]^, ord: Ordering[B]) = this(underlying, underlying.length, ord) + + @SerialVersionUID(3L) + private[this] class ReverseSorted extends SeqView[A] { + private[this] lazy val _reversed = new SeqView.Reverse(_sorted) + + def apply(i: Int): A = _reversed.apply(i) + def length: Int = len + def iterator: Iterator[A]^{this} = Iterator.empty ++ _reversed.iterator // very lazy + override def knownSize: Int = len + override def isEmpty: Boolean = len == 0 + override def to[C1](factory: Factory[A, C1]): C1 = _reversed.to(factory) + override def reverse: SeqView[A]^{outer} = outer + override protected def reversed: Iterable[A] = outer.unsafeAssumePure + + override def sorted[B1 >: A](implicit ord1: Ordering[B1]): SeqView[A]^{this} = + if (ord1 == Sorted.this.ord) outer.unsafeAssumePure + else if (ord1.isReverseOf(Sorted.this.ord)) this + else new Sorted(elems, len, ord1) + } + + @volatile private[this] var evaluated = false + + private[this] lazy val _sorted: Seq[A] = { + val res = { + val len = this.len + if (len == 0) Nil + else if (len == 1) List(underlying.head) + else { + val arr = new Array[Any](len) // Array[Any] =:= Array[AnyRef] + underlying.copyToArray(arr) + java.util.Arrays.sort(arr.asInstanceOf[Array[AnyRef]], ord.asInstanceOf[Ordering[AnyRef]]) + // casting the Array[AnyRef] to Array[A] and creating an ArraySeq from it + // is safe because: + // - the ArraySeq is immutable, and items that are not of type A + // cannot be added to it + // - we know it only contains items of type A (and if this collection + // contains items of another type, we'd get a CCE anyway) + // - the cast doesn't actually do anything in the runtime because the + // type of A is not known and Array[_] is Array[AnyRef] + immutable.ArraySeq.unsafeWrapArray(arr.asInstanceOf[Array[A]]) + } + } + evaluated = true + underlying = null + res + } + + private[this] def elems: SomeSeqOps[A]^{this} = { + val orig = underlying + if (evaluated) _sorted else orig + } + + def apply(i: Int): A = _sorted.apply(i) + def length: Int = len + def iterator: Iterator[A]^{this} = Iterator.empty ++ _sorted.iterator // very lazy + override def knownSize: Int = len + override def isEmpty: Boolean = len == 0 + override def to[C1](factory: Factory[A, C1]): C1 = _sorted.to(factory) + override def reverse: SeqView[A] = new ReverseSorted + // we know `_sorted` is either tiny or has efficient random access, + // so this is acceptable for `reversed` + override protected def reversed: Iterable[A] = new ReverseSorted + + override def sorted[B1 >: A](implicit ord1: Ordering[B1]): SeqView[A]^{this} = + if (ord1 == this.ord) this + else if (ord1.isReverseOf(this.ord)) reverse + else new Sorted(elems, len, ord1) + } +} + +/** Explicit instantiation of the `SeqView` trait to reduce class file size in subclasses. */ +@SerialVersionUID(3L) +abstract class AbstractSeqView[+A] extends AbstractView[A] with SeqView[A] From 0ada1d4c3724ef7b0e8e27e36ebb26e1f7f83fe4 Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 13:12:59 +0100 Subject: [PATCH 03/89] Add IndexedSeqView to lib --- .../stdlib/collection/IndexedSeq.scala | 6 +- .../stdlib/collection/IndexedSeqView.scala | 187 ++++++++++++++++++ 2 files changed, 191 insertions(+), 2 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/IndexedSeqView.scala diff --git a/tests/pos-special/stdlib/collection/IndexedSeq.scala b/tests/pos-special/stdlib/collection/IndexedSeq.scala index 6e8e2bd0dc66..a2d4cc942231 100644 --- a/tests/pos-special/stdlib/collection/IndexedSeq.scala +++ b/tests/pos-special/stdlib/collection/IndexedSeq.scala @@ -18,6 +18,8 @@ import scala.collection.Searching.{Found, InsertionPoint, SearchResult} import scala.collection.Stepper.EfficientSplit import scala.math.Ordering import language.experimental.captureChecking +import caps.unsafe.unsafeAssumePure + /** Base trait for indexed sequences that have efficient `apply` and `length` */ trait IndexedSeq[+A] extends Seq[A] @@ -33,7 +35,7 @@ trait IndexedSeq[+A] extends Seq[A] object IndexedSeq extends SeqFactory.Delegate[IndexedSeq](immutable.IndexedSeq) /** Base trait for indexed Seq operations */ -trait IndexedSeqOps[+A, +CC[_], +C] extends Any with SeqOps[A, CC, C] { self => +trait IndexedSeqOps[+A, +CC[_], +C] extends Any with IndexedSeqViewOps[A, CC, C] with SeqOps[A, CC, C] { self => def iterator: Iterator[A] = view.iterator @@ -86,7 +88,7 @@ trait IndexedSeqOps[+A, +CC[_], +C] extends Any with SeqOps[A, CC, C] { self => override def dropRight(n: Int): C = fromSpecific(new IndexedSeqView.DropRight(this, n)) - override def map[B](f: A => B): CC[B] = iterableFactory.from(new IndexedSeqView.Map(this, f)) + override def map[B](f: A => B): CC[B] = iterableFactory.from(new IndexedSeqView.Map(this, f)).unsafeAssumePure override def reverse: C = fromSpecific(new IndexedSeqView.Reverse(this)) diff --git a/tests/pos-special/stdlib/collection/IndexedSeqView.scala b/tests/pos-special/stdlib/collection/IndexedSeqView.scala new file mode 100644 index 000000000000..41edbf4448c8 --- /dev/null +++ b/tests/pos-special/stdlib/collection/IndexedSeqView.scala @@ -0,0 +1,187 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.annotation.nowarn +import language.experimental.captureChecking + +trait IndexedSeqViewOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { + self: IndexedSeqViewOps[A, CC, C]^ => +} + +/** View defined in terms of indexing a range */ +trait IndexedSeqView[+A] extends IndexedSeqViewOps[A, View, View[A]] with SeqView[A] { + self: IndexedSeqView[A]^ => + + override def view: IndexedSeqView[A]^{this} = this + + @deprecated("Use .view.slice(from, until) instead of .view(from, until)", "2.13.0") + override def view(from: Int, until: Int): IndexedSeqView[A]^{this} = view.slice(from, until) + + override def iterator: Iterator[A]^{this} = new IndexedSeqView.IndexedSeqViewIterator(this) + override def reverseIterator: Iterator[A]^{this} = new IndexedSeqView.IndexedSeqViewReverseIterator(this) + + override def appended[B >: A](elem: B): IndexedSeqView[B]^{this} = new IndexedSeqView.Appended(this, elem) + override def prepended[B >: A](elem: B): IndexedSeqView[B]^{this} = new IndexedSeqView.Prepended(elem, this) + override def take(n: Int): IndexedSeqView[A]^{this} = new IndexedSeqView.Take(this, n) + override def takeRight(n: Int): IndexedSeqView[A]^{this} = new IndexedSeqView.TakeRight(this, n) + override def drop(n: Int): IndexedSeqView[A]^{this} = new IndexedSeqView.Drop(this, n) + override def dropRight(n: Int): IndexedSeqView[A]^{this} = new IndexedSeqView.DropRight(this, n) + override def map[B](f: A => B): IndexedSeqView[B]^{this, f} = new IndexedSeqView.Map(this, f) + override def reverse: IndexedSeqView[A]^{this} = new IndexedSeqView.Reverse(this) + override def slice(from: Int, until: Int): IndexedSeqView[A]^{this} = new IndexedSeqView.Slice(this, from, until) + override def tapEach[U](f: A => U): IndexedSeqView[A]^{this, f} = new IndexedSeqView.Map(this, { (a: A) => f(a); a}) + + def concat[B >: A](suffix: IndexedSeqView.SomeIndexedSeqViewOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(this, suffix) + def appendedAll[B >: A](suffix: IndexedSeqView.SomeIndexedSeqViewOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(this, suffix) + def prependedAll[B >: A](prefix: IndexedSeqView.SomeIndexedSeqViewOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(prefix, this) + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "IndexedSeqView" +} + +object IndexedSeqView { + + @SerialVersionUID(3L) + private[collection] class IndexedSeqViewIterator[A](self: IndexedSeqView[A]^) extends AbstractIterator[A] with Serializable { + this: IndexedSeqViewIterator[A]^ => + private[this] var current = 0 + private[this] var remainder = self.length + override def knownSize: Int = remainder + @inline private[this] def _hasNext: Boolean = remainder > 0 + def hasNext: Boolean = _hasNext + def next(): A = + if (_hasNext) { + val r = self(current) + current += 1 + remainder -= 1 + r + } else Iterator.empty.next() + + override def drop(n: Int): Iterator[A]^{this} = { + if (n > 0) { + current += n + remainder = Math.max(0, remainder - n) + } + this + } + + override protected def sliceIterator(from: Int, until: Int): Iterator[A]^{this} = { + + def formatRange(value : Int) : Int = if (value < 0) 0 else if (value > remainder) remainder else value + + val formatFrom = formatRange(from) + val formatUntil = formatRange(until) + remainder = Math.max(0, formatUntil - formatFrom) + current = current + formatFrom + this + } + } + @SerialVersionUID(3L) + private[collection] class IndexedSeqViewReverseIterator[A](self: IndexedSeqView[A]^) extends AbstractIterator[A] with Serializable { + this: IndexedSeqViewReverseIterator[A]^ => + private[this] var remainder = self.length + private[this] var pos = remainder - 1 + @inline private[this] def _hasNext: Boolean = remainder > 0 + def hasNext: Boolean = _hasNext + def next(): A = + if (_hasNext) { + val r = self(pos) + pos -= 1 + remainder -= 1 + r + } else Iterator.empty.next() + + // from < 0 means don't move pos, until < 0 means don't limit remainder + // + override protected def sliceIterator(from: Int, until: Int): Iterator[A]^{this} = { + if (_hasNext) { + if (remainder <= from) remainder = 0 // exhausted by big skip + else if (from <= 0) { // no skip, pos is same + if (until >= 0 && until < remainder) remainder = until // ...limited by until + } + else { + pos -= from // skip ahead + if (until >= 0 && until < remainder) { // ...limited by until + if (until <= from) remainder = 0 // ...exhausted if limit is smaller than skip + else remainder = until - from // ...limited by until, less the skip + } + else remainder -= from // ...otherwise just less the skip + } + } + this + } + } + + /** An `IndexedSeqViewOps` whose collection type and collection type constructor are unknown */ + type SomeIndexedSeqViewOps[A] = IndexedSeqViewOps[A, AnyConstr, _] + + @SerialVersionUID(3L) + class Id[+A](underlying: SomeIndexedSeqViewOps[A]^) + extends SeqView.Id(underlying) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class Appended[+A](underlying: SomeIndexedSeqViewOps[A]^, elem: A) + extends SeqView.Appended(underlying, elem) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class Prepended[+A](elem: A, underlying: SomeIndexedSeqViewOps[A]^) + extends SeqView.Prepended(elem, underlying) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class Concat[A](prefix: SomeIndexedSeqViewOps[A]^, suffix: SomeIndexedSeqViewOps[A]^) + extends SeqView.Concat[A](prefix, suffix) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class Take[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + extends SeqView.Take(underlying, n) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class TakeRight[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + extends SeqView.TakeRight(underlying, n) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class Drop[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + extends SeqView.Drop[A](underlying, n) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class DropRight[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + extends SeqView.DropRight[A](underlying, n) with IndexedSeqView[A] + + @SerialVersionUID(3L) + class Map[A, B](underlying: SomeIndexedSeqViewOps[A]^, f: A => B) + extends SeqView.Map(underlying, f) with IndexedSeqView[B] + + @SerialVersionUID(3L) + class Reverse[A](underlying: SomeIndexedSeqViewOps[A]^) extends SeqView.Reverse[A](underlying) with IndexedSeqView[A] { + override def reverse: IndexedSeqView[A] = underlying match { + case x: IndexedSeqView[A] => x + case _ => super.reverse + } + } + + @SerialVersionUID(3L) + class Slice[A](underlying: SomeIndexedSeqViewOps[A]^, from: Int, until: Int) extends AbstractIndexedSeqView[A] { + protected val lo = from max 0 + protected val hi = (until max 0) min underlying.length + protected val len = (hi - lo) max 0 + @throws[IndexOutOfBoundsException] + def apply(i: Int): A = underlying(lo + i) + def length: Int = len + } +} + +/** Explicit instantiation of the `IndexedSeqView` trait to reduce class file size in subclasses. */ +@SerialVersionUID(3L) +abstract class AbstractIndexedSeqView[+A] extends AbstractSeqView[A] with IndexedSeqView[A] From dbd0c0e0375b357242414003ec7b5e3fa589ee85 Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 14:40:43 +0100 Subject: [PATCH 04/89] Add CheckedIndexedView to stdlib --- .../stdlib/collection/IndexedSeqView.scala | 30 ++--- .../mutable/CheckedIndexedSeqView.scala | 120 ++++++++++++++++++ 2 files changed, 135 insertions(+), 15 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/mutable/CheckedIndexedSeqView.scala diff --git a/tests/pos-special/stdlib/collection/IndexedSeqView.scala b/tests/pos-special/stdlib/collection/IndexedSeqView.scala index 41edbf4448c8..a16e06fa707d 100644 --- a/tests/pos-special/stdlib/collection/IndexedSeqView.scala +++ b/tests/pos-special/stdlib/collection/IndexedSeqView.scala @@ -43,9 +43,9 @@ trait IndexedSeqView[+A] extends IndexedSeqViewOps[A, View, View[A]] with SeqVie override def slice(from: Int, until: Int): IndexedSeqView[A]^{this} = new IndexedSeqView.Slice(this, from, until) override def tapEach[U](f: A => U): IndexedSeqView[A]^{this, f} = new IndexedSeqView.Map(this, { (a: A) => f(a); a}) - def concat[B >: A](suffix: IndexedSeqView.SomeIndexedSeqViewOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(this, suffix) - def appendedAll[B >: A](suffix: IndexedSeqView.SomeIndexedSeqViewOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(this, suffix) - def prependedAll[B >: A](prefix: IndexedSeqView.SomeIndexedSeqViewOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(prefix, this) + def concat[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(this, suffix) + def appendedAll[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(this, suffix) + def prependedAll[B >: A](prefix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B]^{this} = new IndexedSeqView.Concat(prefix, this) @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") override protected[this] def stringPrefix: String = "IndexedSeqView" @@ -125,46 +125,46 @@ object IndexedSeqView { } /** An `IndexedSeqViewOps` whose collection type and collection type constructor are unknown */ - type SomeIndexedSeqViewOps[A] = IndexedSeqViewOps[A, AnyConstr, _] + type SomeIndexedSeqOps[A] = IndexedSeqViewOps[A, AnyConstr, _] @SerialVersionUID(3L) - class Id[+A](underlying: SomeIndexedSeqViewOps[A]^) + class Id[+A](underlying: SomeIndexedSeqOps[A]^) extends SeqView.Id(underlying) with IndexedSeqView[A] @SerialVersionUID(3L) - class Appended[+A](underlying: SomeIndexedSeqViewOps[A]^, elem: A) + class Appended[+A](underlying: SomeIndexedSeqOps[A]^, elem: A) extends SeqView.Appended(underlying, elem) with IndexedSeqView[A] @SerialVersionUID(3L) - class Prepended[+A](elem: A, underlying: SomeIndexedSeqViewOps[A]^) + class Prepended[+A](elem: A, underlying: SomeIndexedSeqOps[A]^) extends SeqView.Prepended(elem, underlying) with IndexedSeqView[A] @SerialVersionUID(3L) - class Concat[A](prefix: SomeIndexedSeqViewOps[A]^, suffix: SomeIndexedSeqViewOps[A]^) + class Concat[A](prefix: SomeIndexedSeqOps[A]^, suffix: SomeIndexedSeqOps[A]^) extends SeqView.Concat[A](prefix, suffix) with IndexedSeqView[A] @SerialVersionUID(3L) - class Take[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + class Take[A](underlying: SomeIndexedSeqOps[A]^, n: Int) extends SeqView.Take(underlying, n) with IndexedSeqView[A] @SerialVersionUID(3L) - class TakeRight[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + class TakeRight[A](underlying: SomeIndexedSeqOps[A]^, n: Int) extends SeqView.TakeRight(underlying, n) with IndexedSeqView[A] @SerialVersionUID(3L) - class Drop[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + class Drop[A](underlying: SomeIndexedSeqOps[A]^, n: Int) extends SeqView.Drop[A](underlying, n) with IndexedSeqView[A] @SerialVersionUID(3L) - class DropRight[A](underlying: SomeIndexedSeqViewOps[A]^, n: Int) + class DropRight[A](underlying: SomeIndexedSeqOps[A]^, n: Int) extends SeqView.DropRight[A](underlying, n) with IndexedSeqView[A] @SerialVersionUID(3L) - class Map[A, B](underlying: SomeIndexedSeqViewOps[A]^, f: A => B) + class Map[A, B](underlying: SomeIndexedSeqOps[A]^, f: A => B) extends SeqView.Map(underlying, f) with IndexedSeqView[B] @SerialVersionUID(3L) - class Reverse[A](underlying: SomeIndexedSeqViewOps[A]^) extends SeqView.Reverse[A](underlying) with IndexedSeqView[A] { + class Reverse[A](underlying: SomeIndexedSeqOps[A]^) extends SeqView.Reverse[A](underlying) with IndexedSeqView[A] { override def reverse: IndexedSeqView[A] = underlying match { case x: IndexedSeqView[A] => x case _ => super.reverse @@ -172,7 +172,7 @@ object IndexedSeqView { } @SerialVersionUID(3L) - class Slice[A](underlying: SomeIndexedSeqViewOps[A]^, from: Int, until: Int) extends AbstractIndexedSeqView[A] { + class Slice[A](underlying: SomeIndexedSeqOps[A]^, from: Int, until: Int) extends AbstractIndexedSeqView[A] { protected val lo = from max 0 protected val hi = (until max 0) min underlying.length protected val len = (hi - lo) max 0 diff --git a/tests/pos-special/stdlib/collection/mutable/CheckedIndexedSeqView.scala b/tests/pos-special/stdlib/collection/mutable/CheckedIndexedSeqView.scala new file mode 100644 index 000000000000..152b6cc9ffc7 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/CheckedIndexedSeqView.scala @@ -0,0 +1,120 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable +import language.experimental.captureChecking + +private[mutable] trait CheckedIndexedSeqView[+A] extends IndexedSeqView[A] { + this: CheckedIndexedSeqView[A]^ => + + protected val mutationCount: () => Int + + override def iterator: Iterator[A]^{this} = new CheckedIndexedSeqView.CheckedIterator(this, mutationCount()) + override def reverseIterator: Iterator[A]^{this} = new CheckedIndexedSeqView.CheckedReverseIterator(this, mutationCount()) + + override def appended[B >: A](elem: B): IndexedSeqView[B]^{this} = new CheckedIndexedSeqView.Appended(this, elem)(mutationCount) + override def prepended[B >: A](elem: B): IndexedSeqView[B]^{this} = new CheckedIndexedSeqView.Prepended(elem, this)(mutationCount) + override def take(n: Int): IndexedSeqView[A]^{this} = new CheckedIndexedSeqView.Take(this, n)(mutationCount) + override def takeRight(n: Int): IndexedSeqView[A]^{this} = new CheckedIndexedSeqView.TakeRight(this, n)(mutationCount) + override def drop(n: Int): IndexedSeqView[A]^{this} = new CheckedIndexedSeqView.Drop(this, n)(mutationCount) + override def dropRight(n: Int): IndexedSeqView[A]^{this} = new CheckedIndexedSeqView.DropRight(this, n)(mutationCount) + override def map[B](f: A => B): IndexedSeqView[B]^{this, f} = new CheckedIndexedSeqView.Map(this, f)(mutationCount) + override def reverse: IndexedSeqView[A]^{this} = new CheckedIndexedSeqView.Reverse(this)(mutationCount) + override def slice(from: Int, until: Int): IndexedSeqView[A]^{this} = new CheckedIndexedSeqView.Slice(this, from, until)(mutationCount) + override def tapEach[U](f: A => U): IndexedSeqView[A]^{this, f} = new CheckedIndexedSeqView.Map(this, { (a: A) => f(a); a})(mutationCount) + + override def concat[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B]^{this} = new CheckedIndexedSeqView.Concat(this, suffix)(mutationCount) + override def appendedAll[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B]^{this} = new CheckedIndexedSeqView.Concat(this, suffix)(mutationCount) + override def prependedAll[B >: A](prefix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B]^{this} = new CheckedIndexedSeqView.Concat(prefix, this)(mutationCount) +} + +private[mutable] object CheckedIndexedSeqView { + import IndexedSeqView.SomeIndexedSeqOps + + @SerialVersionUID(3L) + private[mutable] class CheckedIterator[A](self: IndexedSeqView[A]^, mutationCount: => Int) + extends IndexedSeqView.IndexedSeqViewIterator[A](self) { + private[this] val expectedCount = mutationCount + override def hasNext: Boolean = { + MutationTracker.checkMutationsForIteration(expectedCount, mutationCount) + super.hasNext + } + } + + @SerialVersionUID(3L) + private[mutable] class CheckedReverseIterator[A](self: IndexedSeqView[A]^, mutationCount: => Int) + extends IndexedSeqView.IndexedSeqViewReverseIterator[A](self) { + private[this] val expectedCount = mutationCount + override def hasNext: Boolean = { + MutationTracker.checkMutationsForIteration(expectedCount, mutationCount) + super.hasNext + } + } + + @SerialVersionUID(3L) + class Id[+A](underlying: SomeIndexedSeqOps[A]^)(protected val mutationCount: () => Int) + extends IndexedSeqView.Id(underlying) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class Appended[+A](underlying: SomeIndexedSeqOps[A]^, elem: A)(protected val mutationCount: () => Int) + extends IndexedSeqView.Appended(underlying, elem) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class Prepended[+A](elem: A, underlying: SomeIndexedSeqOps[A]^)(protected val mutationCount: () => Int) + extends IndexedSeqView.Prepended(elem, underlying) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class Concat[A](prefix: SomeIndexedSeqOps[A]^, suffix: SomeIndexedSeqOps[A]^)(protected val mutationCount: () => Int) + extends IndexedSeqView.Concat[A](prefix, suffix) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class Take[A](underlying: SomeIndexedSeqOps[A]^, n: Int)(protected val mutationCount: () => Int) + extends IndexedSeqView.Take(underlying, n) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class TakeRight[A](underlying: SomeIndexedSeqOps[A]^, n: Int)(protected val mutationCount: () => Int) + extends IndexedSeqView.TakeRight(underlying, n) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class Drop[A](underlying: SomeIndexedSeqOps[A]^, n: Int)(protected val mutationCount: () => Int) + extends IndexedSeqView.Drop[A](underlying, n) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class DropRight[A](underlying: SomeIndexedSeqOps[A]^, n: Int)(protected val mutationCount: () => Int) + extends IndexedSeqView.DropRight[A](underlying, n) with CheckedIndexedSeqView[A] + + @SerialVersionUID(3L) + class Map[A, B](underlying: SomeIndexedSeqOps[A]^, f: A => B)(protected val mutationCount: () => Int) + extends IndexedSeqView.Map(underlying, f) with CheckedIndexedSeqView[B] + + @SerialVersionUID(3L) + class Reverse[A](underlying: SomeIndexedSeqOps[A]^)(protected val mutationCount: () => Int) + extends IndexedSeqView.Reverse[A](underlying) with CheckedIndexedSeqView[A] { + override def reverse: IndexedSeqView[A] = underlying match { + case x: IndexedSeqView[A] => x + case _ => super.reverse + } + } + + @SerialVersionUID(3L) + class Slice[A](underlying: SomeIndexedSeqOps[A]^, from: Int, until: Int)(protected val mutationCount: () => Int) + extends AbstractIndexedSeqView[A] with CheckedIndexedSeqView[A] { + protected val lo = from max 0 + protected val hi = (until max 0) min underlying.length + protected val len = (hi - lo) max 0 + @throws[IndexOutOfBoundsException] + def apply(i: Int): A = underlying(lo + i) + def length: Int = len + } +} From 8a60bc22861b77a9bf9226b70387367b4d69a68f Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 14:42:09 +0100 Subject: [PATCH 05/89] Add ArrayBuffer (unchecked) to stdlib --- .../collection/mutable/ArrayBuffer.scala | 403 ++++++++++++++++++ 1 file changed, 403 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala b/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala new file mode 100644 index 000000000000..e3ddeb71ef8e --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala @@ -0,0 +1,403 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import java.util.Arrays + +import scala.annotation.nowarn +import scala.annotation.tailrec +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable + +/** An implementation of the `Buffer` class using an array to + * represent the assembled sequence internally. Append, update and random + * access take constant time (amortized time). Prepends and removes are + * linear in the buffer size. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#array-buffers "Scala's Collection Library overview"]] + * section on `Array Buffers` for more information. + + * + * @tparam A the type of this arraybuffer's elements. + * + * @define Coll `mutable.ArrayBuffer` + * @define coll array buffer + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@SerialVersionUID(-1582447879429021880L) +class ArrayBuffer[A] private (initialElements: Array[AnyRef], initialSize: Int) + extends AbstractBuffer[A] + with IndexedBuffer[A] + with IndexedSeqOps[A, ArrayBuffer, ArrayBuffer[A]] + with StrictOptimizedSeqOps[A, ArrayBuffer, ArrayBuffer[A]] + with IterableFactoryDefaults[A, ArrayBuffer] + with DefaultSerializable { + + def this() = this(new Array[AnyRef](ArrayBuffer.DefaultInitialSize), 0) + + def this(initialSize: Int) = this(new Array[AnyRef](initialSize max 1), 0) + + @transient private[this] var mutationCount: Int = 0 + + // needs to be `private[collection]` or `protected[collection]` for parallel-collections + protected[collection] var array: Array[AnyRef] = initialElements + protected var size0 = initialSize + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + shape.parUnbox(new ObjectArrayStepper(array, 0, length).asInstanceOf[AnyStepper[A] with EfficientSplit]) + } + + override def knownSize: Int = super[IndexedSeqOps].knownSize + + /** Ensure that the internal array has at least `n` cells. */ + protected def ensureSize(n: Int): Unit = { + array = ArrayBuffer.ensureSize(array, size0, n) + } + + // TODO 3.T: should be `protected`, perhaps `protected[this]` + /** Ensure that the internal array has at least `n` additional cells more than `size0`. */ + private[mutable] def ensureAdditionalSize(n: Int): Unit = { + // `.toLong` to ensure `Long` arithmetic is used and prevent `Int` overflow + array = ArrayBuffer.ensureSize(array, size0, size0.toLong + n) + } + + def sizeHint(size: Int): Unit = + if(size > length && size >= 1) ensureSize(size) + + /** Reduce length to `n`, nulling out all dropped elements */ + private def reduceToSize(n: Int): Unit = { + mutationCount += 1 + Arrays.fill(array, n, size0, null) + size0 = n + } + + /** Trims the ArrayBuffer to an appropriate size for the current + * number of elements (rounding up to the next natural size), + * which may replace the array by a shorter one. + * This allows releasing some unused memory. + */ + def trimToSize(): Unit = { + resize(length) + } + + /** Trims the `array` buffer size down to either a power of 2 + * or Int.MaxValue while keeping first `requiredLength` elements. + */ + private def resize(requiredLength: Int): Unit = + array = ArrayBuffer.downsize(array, requiredLength) + + @inline private def checkWithinBounds(lo: Int, hi: Int) = { + if (lo < 0) throw new IndexOutOfBoundsException(s"$lo is out of bounds (min 0, max ${size0 - 1})") + if (hi > size0) throw new IndexOutOfBoundsException(s"${hi - 1} is out of bounds (min 0, max ${size0 - 1})") + } + + def apply(n: Int): A = { + checkWithinBounds(n, n + 1) + array(n).asInstanceOf[A] + } + + def update(@deprecatedName("n", "2.13.0") index: Int, elem: A): Unit = { + checkWithinBounds(index, index + 1) + mutationCount += 1 + array(index) = elem.asInstanceOf[AnyRef] + } + + def length = size0 + + // TODO: return `IndexedSeqView` rather than `ArrayBufferView` + override def view: ArrayBufferView[A] = new ArrayBufferView(this, () => mutationCount) + + override def iterableFactory: SeqFactory[ArrayBuffer] = ArrayBuffer + + /** Note: This does not actually resize the internal representation. + * See clearAndShrink if you want to also resize internally + */ + def clear(): Unit = reduceToSize(0) + + /** + * Clears this buffer and shrinks to @param size (rounding up to the next + * natural size) + * @param size + */ + def clearAndShrink(size: Int = ArrayBuffer.DefaultInitialSize): this.type = { + clear() + resize(size) + this + } + + def addOne(elem: A): this.type = { + mutationCount += 1 + ensureAdditionalSize(1) + val oldSize = size0 + size0 = oldSize + 1 + this(oldSize) = elem + this + } + + // Overridden to use array copying for efficiency where possible. + override def addAll(elems: IterableOnce[A]): this.type = { + elems match { + case elems: ArrayBuffer[_] => + val elemsLength = elems.size0 + if (elemsLength > 0) { + mutationCount += 1 + ensureAdditionalSize(elemsLength) + Array.copy(elems.array, 0, array, length, elemsLength) + size0 = length + elemsLength + } + case _ => super.addAll(elems) + } + this + } + + def insert(@deprecatedName("n", "2.13.0") index: Int, elem: A): Unit = { + checkWithinBounds(index, index) + mutationCount += 1 + ensureAdditionalSize(1) + Array.copy(array, index, array, index + 1, size0 - index) + size0 += 1 + this(index) = elem + } + + def prepend(elem: A): this.type = { + insert(0, elem) + this + } + + def insertAll(@deprecatedName("n", "2.13.0") index: Int, elems: IterableOnce[A]): Unit = { + checkWithinBounds(index, index) + elems match { + case elems: collection.Iterable[A] => + val elemsLength = elems.size + if (elemsLength > 0) { + mutationCount += 1 + ensureAdditionalSize(elemsLength) + val len = size0 + Array.copy(array, index, array, index + elemsLength, len - index) + // if `elems eq this`, this copy is safe because + // - `elems.array eq this.array` + // - we didn't overwrite the values being inserted after moving them in + // the previous line + // - `copyElemsToArray` will call `System.arraycopy` + // - `System.arraycopy` will effectively "read" all the values before + // overwriting any of them when two arrays are the the same reference + val actual = IterableOnce.copyElemsToArray(elems, array.asInstanceOf[Array[Any]], index, elemsLength) + if (actual != elemsLength) throw new IllegalStateException(s"Copied $actual of $elemsLength") + size0 = len + elemsLength // update size AFTER the copy, in case we're inserting a proxy + } + case _ => insertAll(index, ArrayBuffer.from(elems)) + } + } + + /** Note: This does not actually resize the internal representation. + * See trimToSize if you want to also resize internally + */ + def remove(@deprecatedName("n", "2.13.0") index: Int): A = { + checkWithinBounds(index, index + 1) + val res = this(index) + Array.copy(array, index + 1, array, index, size0 - (index + 1)) + reduceToSize(size0 - 1) + res + } + + /** Note: This does not actually resize the internal representation. + * See trimToSize if you want to also resize internally + */ + def remove(@deprecatedName("n", "2.13.0") index: Int, count: Int): Unit = + if (count > 0) { + checkWithinBounds(index, index + count) + Array.copy(array, index + count, array, index, size0 - (index + count)) + reduceToSize(size0 - count) + } else if (count < 0) { + throw new IllegalArgumentException("removing negative number of elements: " + count) + } + + @deprecated("Use 'this' instance instead", "2.13.0") + @deprecatedOverriding("ArrayBuffer[A] no longer extends Builder[A, ArrayBuffer[A]]", "2.13.0") + @inline def result(): this.type = this + + @deprecated("Use 'new GrowableBuilder(this).mapResult(f)' instead", "2.13.0") + @deprecatedOverriding("ArrayBuffer[A] no longer extends Builder[A, ArrayBuffer[A]]", "2.13.0") + @inline def mapResult[NewTo](f: (ArrayBuffer[A]) => NewTo): Builder[A, NewTo] = new GrowableBuilder[A, ArrayBuffer[A]](this).mapResult(f) + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "ArrayBuffer" + + override def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) + if(copied > 0) { + Array.copy(array, 0, xs, start, copied) + } + copied + } + + /** Sorts this $coll in place according to an Ordering. + * + * @see [[scala.collection.mutable.IndexedSeqOps.sortInPlace]] + * @param ord the ordering to be used to compare elements. + * @return modified input $coll sorted according to the ordering `ord`. + */ + override def sortInPlace[B >: A]()(implicit ord: Ordering[B]): this.type = { + if (length > 1) { + mutationCount += 1 + scala.util.Sorting.stableSort(array.asInstanceOf[Array[B]], 0, length) + } + this + } + + @tailrec private def foldl[B](start: Int, end: Int, z: B, op: (B, A) => B): B = + if (start == end) z + else foldl(start + 1, end, op(z, array(start).asInstanceOf[A]), op) + + @tailrec private def foldr[B](start: Int, end: Int, z: B, op: (A, B) => B): B = + if (start == end) z + else foldr(start, end - 1, op(array(end - 1).asInstanceOf[A], z), op) + + override def foldLeft[B](z: B)(op: (B, A) => B): B = foldl(0, length, z, op) + + override def foldRight[B](z: B)(op: (A, B) => B): B = foldr(0, length, z, op) + + override def reduceLeft[B >: A](op: (B, A) => B): B = if (length > 0) foldl(1, length, array(0).asInstanceOf[B], op) else super.reduceLeft(op) + + override def reduceRight[B >: A](op: (A, B) => B): B = if (length > 0) foldr(0, length - 1, array(length - 1).asInstanceOf[B], op) else super.reduceRight(op) +} + +/** + * Factory object for the `ArrayBuffer` class. + * + * $factoryInfo + * + * @define coll array buffer + * @define Coll `mutable.ArrayBuffer` + */ +@SerialVersionUID(3L) +object ArrayBuffer extends StrictOptimizedSeqFactory[ArrayBuffer] { + final val DefaultInitialSize = 16 + private[this] val emptyArray = new Array[AnyRef](0) + + def from[B](coll: collection.IterableOnce[B]): ArrayBuffer[B] = { + val k = coll.knownSize + if (k >= 0) { + // Avoid reallocation of buffer if length is known + val array = ensureSize(emptyArray, 0, k) // don't duplicate sizing logic, and check VM array size limit + val actual = IterableOnce.copyElemsToArray(coll, array.asInstanceOf[Array[Any]]) + if (actual != k) throw new IllegalStateException(s"Copied $actual of $k") + new ArrayBuffer[B](array, k) + } + else new ArrayBuffer[B] ++= coll + } + + def newBuilder[A]: Builder[A, ArrayBuffer[A]] = + new GrowableBuilder[A, ArrayBuffer[A]](empty) { + override def sizeHint(size: Int): Unit = elems.ensureSize(size) + } + + def empty[A]: ArrayBuffer[A] = new ArrayBuffer[A]() + + /** + * @param arrayLen the length of the backing array + * @param targetLen the minimum length to resize up to + * @return -1 if no resizing is needed, or the size for the new array otherwise + */ + private def resizeUp(arrayLen: Long, targetLen: Long): Int = { + if (targetLen <= arrayLen) -1 + else { + if (targetLen > Int.MaxValue) throw new Exception(s"Collections cannot have more than ${Int.MaxValue} elements") + IterableOnce.checkArraySizeWithinVMLimit(targetLen.toInt) // safe because `targetSize <= Int.MaxValue` + + val newLen = math.max(targetLen, math.max(arrayLen * 2, DefaultInitialSize)) + math.min(newLen, scala.runtime.PStatics.VM_MaxArraySize).toInt + } + } + // if necessary, copy (curSize elements of) the array to a new array of capacity n. + // Should use Array.copyOf(array, resizeEnsuring(array.length))? + private def ensureSize(array: Array[AnyRef], curSize: Int, targetSize: Long): Array[AnyRef] = { + val newLen = resizeUp(array.length, targetSize) + if (newLen < 0) array + else { + val res = new Array[AnyRef](newLen) + System.arraycopy(array, 0, res, 0, curSize) + res + } + } + + /** + * @param arrayLen the length of the backing array + * @param targetLen the length to resize down to, if smaller than `arrayLen` + * @return -1 if no resizing is needed, or the size for the new array otherwise + */ + private def resizeDown(arrayLen: Int, targetLen: Int): Int = + if (targetLen >= arrayLen) -1 else math.max(targetLen, 0) + private def downsize(array: Array[AnyRef], targetSize: Int): Array[AnyRef] = { + val newLen = resizeDown(array.length, targetSize) + if (newLen < 0) array + else if (newLen == 0) emptyArray + else { + val res = new Array[AnyRef](newLen) + System.arraycopy(array, 0, res, 0, targetSize) + res + } + } +} + +// TODO: use `CheckedIndexedSeqView.Id` once we can change the return type of `ArrayBuffer#view` +final class ArrayBufferView[A] private[mutable](underlying: ArrayBuffer[A], mutationCount: () => Int) + extends AbstractIndexedSeqView[A] { + @deprecated("never intended to be public; call ArrayBuffer#view instead", since = "2.13.7") + def this(array: Array[AnyRef], length: Int) = { + // this won't actually track mutation, but it would be a pain to have the implementation + // check if we have a method to get the current mutation count or not on every method and + // change what it does based on that. hopefully no one ever calls this. + this({ + val _array = array + val _length = length + new ArrayBuffer[A](0) { + this.array = _array + this.size0 = _length + } + }, () => 0) + } + + @deprecated("never intended to be public", since = "2.13.7") + def array: Array[AnyRef] = underlying.toArray[Any].asInstanceOf[Array[AnyRef]] + + @throws[IndexOutOfBoundsException] + def apply(n: Int): A = underlying(n) + def length: Int = underlying.length + override protected[this] def className = "ArrayBufferView" + + // we could inherit all these from `CheckedIndexedSeqView`, except this class is public + override def iterator: Iterator[A] = new CheckedIndexedSeqView.CheckedIterator(this, mutationCount()) + override def reverseIterator: Iterator[A] = new CheckedIndexedSeqView.CheckedReverseIterator(this, mutationCount()) + + override def appended[B >: A](elem: B): IndexedSeqView[B] = new CheckedIndexedSeqView.Appended(this, elem)(mutationCount) + override def prepended[B >: A](elem: B): IndexedSeqView[B] = new CheckedIndexedSeqView.Prepended(elem, this)(mutationCount) + override def take(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.Take(this, n)(mutationCount) + override def takeRight(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.TakeRight(this, n)(mutationCount) + override def drop(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.Drop(this, n)(mutationCount) + override def dropRight(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.DropRight(this, n)(mutationCount) + override def map[B](f: A => B): IndexedSeqView[B] = new CheckedIndexedSeqView.Map(this, f)(mutationCount) + override def reverse: IndexedSeqView[A] = new CheckedIndexedSeqView.Reverse(this)(mutationCount) + override def slice(from: Int, until: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.Slice(this, from, until)(mutationCount) + override def tapEach[U](f: A => U): IndexedSeqView[A] = new CheckedIndexedSeqView.Map(this, { (a: A) => f(a); a})(mutationCount) + + override def concat[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B] = new CheckedIndexedSeqView.Concat(this, suffix)(mutationCount) + override def appendedAll[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B] = new CheckedIndexedSeqView.Concat(this, suffix)(mutationCount) + override def prependedAll[B >: A](prefix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B] = new CheckedIndexedSeqView.Concat(prefix, this)(mutationCount) +} From 61bf13943e2d67bea391abbc526e294eb5fc52bc Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 15:01:58 +0100 Subject: [PATCH 06/89] Rename annotation source file --- .../unchecked/uncheckedCapabilityLeaks.scala | 12 ------------ .../annotation/unchecked/uncheckedCaptures.scala | 12 ++++++++++++ 2 files changed, 12 insertions(+), 12 deletions(-) create mode 100644 library/src/scala/annotation/unchecked/uncheckedCaptures.scala diff --git a/library/src/scala/annotation/unchecked/uncheckedCapabilityLeaks.scala b/library/src/scala/annotation/unchecked/uncheckedCapabilityLeaks.scala index 477ac6d742f7..e69de29bb2d1 100644 --- a/library/src/scala/annotation/unchecked/uncheckedCapabilityLeaks.scala +++ b/library/src/scala/annotation/unchecked/uncheckedCapabilityLeaks.scala @@ -1,12 +0,0 @@ -package scala.annotation -package unchecked - -/** An annotation for mutable variables that are allowed to capture - * the root capability `cap`. Allowing this is not capture safe since - * it can cause leakage of capabilities from local scopes by assigning - * values retaining such capabilties to the annotated variable in - * an outer scope. - */ -class uncheckedCaptures extends StaticAnnotation - - diff --git a/library/src/scala/annotation/unchecked/uncheckedCaptures.scala b/library/src/scala/annotation/unchecked/uncheckedCaptures.scala new file mode 100644 index 000000000000..477ac6d742f7 --- /dev/null +++ b/library/src/scala/annotation/unchecked/uncheckedCaptures.scala @@ -0,0 +1,12 @@ +package scala.annotation +package unchecked + +/** An annotation for mutable variables that are allowed to capture + * the root capability `cap`. Allowing this is not capture safe since + * it can cause leakage of capabilities from local scopes by assigning + * values retaining such capabilties to the annotated variable in + * an outer scope. + */ +class uncheckedCaptures extends StaticAnnotation + + From 6b91167a6b4d2de79afed8a9aa9326c8154f1b69 Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 18:30:51 +0100 Subject: [PATCH 07/89] Also count @Sealed annotated abstract types as sealed Also count abstract types that have a @Sealed annotation on their bound as sealed. That way, we get free propagation into synthesized type parameters. We should probably unify this scheme and `sealed` modifiers. --- compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index ad216c47d2f5..e4c6b60bb894 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -163,7 +163,8 @@ object CheckCaptures: capt.println(i"disallow $t, $tp, $what, ${t.symbol.is(Sealed)}") t.info match case TypeBounds(_, hi) - if !t.symbol.is(Sealed) && !t.symbol.isParametricIn(carrier) => + if !t.symbol.is(Sealed) && !hi.hasAnnotation(defn.Caps_SealedAnnot) + && !t.symbol.isParametricIn(carrier) => if hi.isAny then report.error( em"""$what cannot $have $tp since From d3876ad804f5a0306fae2cc57ad8a56a3744e5c1 Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 18:38:29 +0100 Subject: [PATCH 08/89] Add ArrayBuffer and GrowableBuilder to stdlib --- .../captures/sealed-lowerbound.scala | 12 ++++++ .../stdlib/collection/IterableOnce.scala | 6 +-- .../stdlib/collection/Iterator.scala | 5 ++- tests/pos-special/stdlib/collection/Seq.scala | 4 +- .../pos-special/stdlib/collection/View.scala | 2 +- .../collection/mutable/ArrayBuffer.scala | 31 +++++++++------- .../stdlib/collection/mutable/Buffer.scala | 2 +- .../collection/mutable/GrowableBuilder.scala | 37 +++++++++++++++++++ 8 files changed, 78 insertions(+), 21 deletions(-) create mode 100644 tests/pos-custom-args/captures/sealed-lowerbound.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/GrowableBuilder.scala diff --git a/tests/pos-custom-args/captures/sealed-lowerbound.scala b/tests/pos-custom-args/captures/sealed-lowerbound.scala new file mode 100644 index 000000000000..e848f784cddc --- /dev/null +++ b/tests/pos-custom-args/captures/sealed-lowerbound.scala @@ -0,0 +1,12 @@ +def foo[sealed B](x: B): B = x + +def bar[B, sealed A >: B](x: A): A = foo[A](x) + +class C[sealed A] + +class CV[sealed A](x: Int): + def this() = this: + val x = new C[A]: + println("foo") + 0 + diff --git a/tests/pos-special/stdlib/collection/IterableOnce.scala b/tests/pos-special/stdlib/collection/IterableOnce.scala index 6836a3bac39a..3886d7dccb95 100644 --- a/tests/pos-special/stdlib/collection/IterableOnce.scala +++ b/tests/pos-special/stdlib/collection/IterableOnce.scala @@ -162,7 +162,7 @@ final class IterableOnceExtensionMethods[A](private val it: IterableOnce[A]) ext def to[C1](factory: Factory[A, C1]): C1 = factory.fromSpecific(it) @deprecated("Use .iterator.to(ArrayBuffer) instead", "2.13.0") - def toBuffer[B >: A]: mutable.Buffer[B] = mutable.ArrayBuffer.from(it) + def toBuffer[sealed B >: A]: mutable.Buffer[B] = mutable.ArrayBuffer.from(it) @deprecated("Use .iterator.toArray", "2.13.0") def toArray[B >: A: ClassTag]: Array[B] = it match { @@ -272,7 +272,7 @@ object IterableOnce { math.max(math.min(math.min(len, srcLen), destLen - start), 0) /** Calls `copyToArray` on the given collection, regardless of whether or not it is an `Iterable`. */ - @inline private[collection] def copyElemsToArray[A, B >: A](elems: IterableOnce[A], + @inline private[collection] def copyElemsToArray[A, B >: A](elems: IterableOnce[A]^, xs: Array[B], start: Int = 0, len: Int = Int.MaxValue): Int = @@ -1312,7 +1312,7 @@ trait IterableOnceOps[+A, +CC[_], +C] extends Any { this: IterableOnce[A]^ => @deprecated("Use .to(LazyList) instead of .toStream", "2.13.0") @`inline` final def toStream: immutable.Stream[A] = to(immutable.Stream) - @`inline` final def toBuffer[B >: A]: mutable.Buffer[B] = mutable.Buffer.from(this) + @`inline` final def toBuffer[sealed B >: A]: mutable.Buffer[B] = mutable.Buffer.from(this) /** Convert collection to array. * diff --git a/tests/pos-special/stdlib/collection/Iterator.scala b/tests/pos-special/stdlib/collection/Iterator.scala index ecd8d985bbf0..0c96aa35501b 100644 --- a/tests/pos-special/stdlib/collection/Iterator.scala +++ b/tests/pos-special/stdlib/collection/Iterator.scala @@ -18,6 +18,7 @@ import scala.annotation.unchecked.{uncheckedVariance, uncheckedCaptures} import scala.runtime.Statics import language.experimental.captureChecking import caps.unsafe.unsafeAssumePure +import annotation.unchecked.uncheckedCaptures /** Iterators are data structures that allow to iterate over a sequence @@ -416,7 +417,9 @@ trait Iterator[+A] extends IterableOnce[A] with IterableOnceOps[A, Iterator, Ite } @deprecated("Call scanRight on an Iterable instead.", "2.13.0") - def scanRight[B](z: B)(op: (A, B) => B): Iterator[B]^{this} = ArrayBuffer.from(this).scanRight(z)(op).iterator + def scanRight[B](z: B)(op: (A, B) => B): Iterator[B]^{this} = + ArrayBuffer.from[A @uncheckedCaptures](this).scanRight(z)(op).iterator + // @uncheckedCaptures is safe since the ArrayBuffer is local temporrary storage def indexWhere(p: A => Boolean, from: Int = 0): Int = { var i = math.max(from, 0) diff --git a/tests/pos-special/stdlib/collection/Seq.scala b/tests/pos-special/stdlib/collection/Seq.scala index 81f39b3538cf..05b315c49a8c 100644 --- a/tests/pos-special/stdlib/collection/Seq.scala +++ b/tests/pos-special/stdlib/collection/Seq.scala @@ -18,6 +18,7 @@ import Searching.{Found, InsertionPoint, SearchResult} import scala.annotation.nowarn import language.experimental.captureChecking import caps.unsafe.unsafeAssumePure +import scala.annotation.unchecked.uncheckedCaptures /** Base trait for sequence collections * @@ -598,7 +599,8 @@ trait SeqOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { self => if (!hasNext) Iterator.empty.next() - val forcedElms = new mutable.ArrayBuffer[A](elms.size) ++= elms + val forcedElms = new mutable.ArrayBuffer[A @uncheckedCaptures](elms.size) ++= elms + // uncheckedCaptures OK since used only locally val result = (newSpecificBuilder ++= forcedElms).result() var i = idxs.length - 2 while(i >= 0 && idxs(i) >= idxs(i+1)) diff --git a/tests/pos-special/stdlib/collection/View.scala b/tests/pos-special/stdlib/collection/View.scala index 85910311a4c3..d91fc0c49939 100644 --- a/tests/pos-special/stdlib/collection/View.scala +++ b/tests/pos-special/stdlib/collection/View.scala @@ -78,7 +78,7 @@ object View extends IterableFactory[View] { def empty[A]: View[A] = Empty - def newBuilder[A]: Builder[A, View[A]] = ArrayBuffer.newBuilder[A].mapResult(from) + def newBuilder[sealed A]: Builder[A, View[A]] = ArrayBuffer.newBuilder[A].mapResult(from) override def apply[A](xs: A*): View[A] = new Elems(xs: _*) diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala b/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala index e3ddeb71ef8e..e0b3edc54690 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala @@ -20,6 +20,8 @@ import scala.annotation.nowarn import scala.annotation.tailrec import scala.collection.Stepper.EfficientSplit import scala.collection.generic.DefaultSerializable +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures /** An implementation of the `Buffer` class using an array to * represent the assembled sequence internally. Append, update and random @@ -40,7 +42,7 @@ import scala.collection.generic.DefaultSerializable * @define willNotTerminateInf */ @SerialVersionUID(-1582447879429021880L) -class ArrayBuffer[A] private (initialElements: Array[AnyRef], initialSize: Int) +class ArrayBuffer[sealed A] private (initialElements: Array[AnyRef], initialSize: Int) extends AbstractBuffer[A] with IndexedBuffer[A] with IndexedSeqOps[A, ArrayBuffer, ArrayBuffer[A]] @@ -151,7 +153,7 @@ class ArrayBuffer[A] private (initialElements: Array[AnyRef], initialSize: Int) } // Overridden to use array copying for efficiency where possible. - override def addAll(elems: IterableOnce[A]): this.type = { + override def addAll(elems: IterableOnce[A]^): this.type = { elems match { case elems: ArrayBuffer[_] => val elemsLength = elems.size0 @@ -180,7 +182,7 @@ class ArrayBuffer[A] private (initialElements: Array[AnyRef], initialSize: Int) this } - def insertAll(@deprecatedName("n", "2.13.0") index: Int, elems: IterableOnce[A]): Unit = { + def insertAll(@deprecatedName("n", "2.13.0") index: Int, elems: IterableOnce[A]^): Unit = { checkWithinBounds(index, index) elems match { case elems: collection.Iterable[A] => @@ -234,7 +236,7 @@ class ArrayBuffer[A] private (initialElements: Array[AnyRef], initialSize: Int) @deprecated("Use 'new GrowableBuilder(this).mapResult(f)' instead", "2.13.0") @deprecatedOverriding("ArrayBuffer[A] no longer extends Builder[A, ArrayBuffer[A]]", "2.13.0") - @inline def mapResult[NewTo](f: (ArrayBuffer[A]) => NewTo): Builder[A, NewTo] = new GrowableBuilder[A, ArrayBuffer[A]](this).mapResult(f) + @inline def mapResult[NewTo](f: (ArrayBuffer[A]) => NewTo): Builder[A, NewTo]^{f} = new GrowableBuilder[A, ArrayBuffer[A]](this).mapResult(f) @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") override protected[this] def stringPrefix = "ArrayBuffer" @@ -291,7 +293,7 @@ object ArrayBuffer extends StrictOptimizedSeqFactory[ArrayBuffer] { final val DefaultInitialSize = 16 private[this] val emptyArray = new Array[AnyRef](0) - def from[B](coll: collection.IterableOnce[B]): ArrayBuffer[B] = { + def from[sealed B](coll: collection.IterableOnce[B]^): ArrayBuffer[B] = { val k = coll.knownSize if (k >= 0) { // Avoid reallocation of buffer if length is known @@ -303,12 +305,12 @@ object ArrayBuffer extends StrictOptimizedSeqFactory[ArrayBuffer] { else new ArrayBuffer[B] ++= coll } - def newBuilder[A]: Builder[A, ArrayBuffer[A]] = + def newBuilder[sealed A]: Builder[A, ArrayBuffer[A]] = new GrowableBuilder[A, ArrayBuffer[A]](empty) { override def sizeHint(size: Int): Unit = elems.ensureSize(size) } - def empty[A]: ArrayBuffer[A] = new ArrayBuffer[A]() + def empty[sealed A]: ArrayBuffer[A] = new ArrayBuffer[A]() /** * @param arrayLen the length of the backing array @@ -357,22 +359,23 @@ object ArrayBuffer extends StrictOptimizedSeqFactory[ArrayBuffer] { } // TODO: use `CheckedIndexedSeqView.Id` once we can change the return type of `ArrayBuffer#view` -final class ArrayBufferView[A] private[mutable](underlying: ArrayBuffer[A], mutationCount: () => Int) - extends AbstractIndexedSeqView[A] { +final class ArrayBufferView[sealed A] private[mutable](underlying: ArrayBuffer[A], mutationCount: () -> Int) + extends AbstractIndexedSeqView[A], Pure { + /* Removed since it poses problems for capture checking @deprecated("never intended to be public; call ArrayBuffer#view instead", since = "2.13.7") def this(array: Array[AnyRef], length: Int) = { // this won't actually track mutation, but it would be a pain to have the implementation // check if we have a method to get the current mutation count or not on every method and // change what it does based on that. hopefully no one ever calls this. this({ - val _array = array + val _array: Array[Object] = array val _length = length new ArrayBuffer[A](0) { this.array = _array this.size0 = _length - } + }: ArrayBuffer[A] }, () => 0) - } + }*/ @deprecated("never intended to be public", since = "2.13.7") def array: Array[AnyRef] = underlying.toArray[Any].asInstanceOf[Array[AnyRef]] @@ -392,10 +395,10 @@ final class ArrayBufferView[A] private[mutable](underlying: ArrayBuffer[A], muta override def takeRight(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.TakeRight(this, n)(mutationCount) override def drop(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.Drop(this, n)(mutationCount) override def dropRight(n: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.DropRight(this, n)(mutationCount) - override def map[B](f: A => B): IndexedSeqView[B] = new CheckedIndexedSeqView.Map(this, f)(mutationCount) + override def map[B](f: A => B): IndexedSeqView[B]^{f} = new CheckedIndexedSeqView.Map(this, f)(mutationCount) override def reverse: IndexedSeqView[A] = new CheckedIndexedSeqView.Reverse(this)(mutationCount) override def slice(from: Int, until: Int): IndexedSeqView[A] = new CheckedIndexedSeqView.Slice(this, from, until)(mutationCount) - override def tapEach[U](f: A => U): IndexedSeqView[A] = new CheckedIndexedSeqView.Map(this, { (a: A) => f(a); a})(mutationCount) + override def tapEach[U](f: A => U): IndexedSeqView[A]^{f} = new CheckedIndexedSeqView.Map(this, { (a: A) => f(a); a})(mutationCount) override def concat[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B] = new CheckedIndexedSeqView.Concat(this, suffix)(mutationCount) override def appendedAll[B >: A](suffix: IndexedSeqView.SomeIndexedSeqOps[B]): IndexedSeqView[B] = new CheckedIndexedSeqView.Concat(this, suffix)(mutationCount) diff --git a/tests/pos-special/stdlib/collection/mutable/Buffer.scala b/tests/pos-special/stdlib/collection/mutable/Buffer.scala index 0a70c75bac0c..f5e6ce66c99a 100644 --- a/tests/pos-special/stdlib/collection/mutable/Buffer.scala +++ b/tests/pos-special/stdlib/collection/mutable/Buffer.scala @@ -18,7 +18,7 @@ import language.experimental.captureChecking /** A `Buffer` is a growable and shrinkable `Seq`. */ -trait Buffer[A] +trait Buffer[sealed A] extends Seq[A] with SeqOps[A, Buffer, Buffer[A]] with Growable[A] diff --git a/tests/pos-special/stdlib/collection/mutable/GrowableBuilder.scala b/tests/pos-special/stdlib/collection/mutable/GrowableBuilder.scala new file mode 100644 index 000000000000..4d6f989e6f3d --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/GrowableBuilder.scala @@ -0,0 +1,37 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.mutable +import language.experimental.captureChecking + +/** The canonical builder for collections that are growable, i.e. that support an + * efficient `+=` method which adds an element to the collection. + * + * GrowableBuilders can produce only a single instance of the collection they are growing. + * + * @define Coll `GrowingBuilder` + * @define coll growing builder + */ +class GrowableBuilder[Elem, To <: Growable[Elem]](protected val elems: To) + extends Builder[Elem, To] { + + def clear(): Unit = elems.clear() + + def result(): To = elems + + def addOne(elem: Elem): this.type = { elems += elem; this } + + override def addAll(xs: IterableOnce[Elem]^): this.type = { elems.addAll(xs); this } + + override def knownSize: Int = elems.knownSize +} From 75c20583229af6ae5772eecee8a03b193085c59b Mon Sep 17 00:00:00 2001 From: odersky Date: Mon, 30 Oct 2023 21:26:57 +0100 Subject: [PATCH 09/89] Coarse restriction to disallow local roots in external types This needs to be refined further for class members, similar to how we check that private types cannot escape from a class API. --- .../dotty/tools/dotc/cc/CheckCaptures.scala | 16 ++++++++++++++ tests/neg-custom-args/captures/filevar.scala | 2 +- .../neg-custom-args/captures/localcaps.check | 12 ++++++++++ .../neg-custom-args/captures/localcaps.scala | 2 +- tests/neg-custom-args/captures/pairs.check | 8 +++++++ tests/neg-custom-args/captures/pairs.scala | 4 ++-- .../recursive-leaking-local-cap.scala | 22 +++++++++++++++++++ .../captures/sealed-classes.scala | 21 ++++++++++++++++++ 8 files changed, 83 insertions(+), 4 deletions(-) create mode 100644 tests/neg-custom-args/captures/localcaps.check create mode 100644 tests/neg-custom-args/captures/recursive-leaking-local-cap.scala create mode 100644 tests/neg-custom-args/captures/sealed-classes.scala diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index e4c6b60bb894..c7b282b49dba 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -1301,6 +1301,20 @@ class CheckCaptures extends Recheck, SymTransformer: checker.traverse(tree.knownType) end healTypeParam + def checkNoLocalRootIn(sym: Symbol, info: Type, pos: SrcPos)(using Context): Unit = + val check = new TypeTraverser: + def traverse(tp: Type) = tp match + case tp: TermRef if tp.isLocalRootCapability => + if tp.localRootOwner == sym then + report.error(i"local root $tp cannot appear in type of $sym", pos) + case tp: ClassInfo => + traverseChildren(tp) + for mbr <- tp.decls do + if !mbr.is(Private) then checkNoLocalRootIn(sym, mbr.info, mbr.srcPos) + case _ => + traverseChildren(tp) + check.traverse(info) + /** Perform the following kinds of checks * - Check all explicitly written capturing types for well-formedness using `checkWellFormedPost`. * - Check that arguments of TypeApplys and AppliedTypes conform to their bounds. @@ -1324,6 +1338,8 @@ class CheckCaptures extends Recheck, SymTransformer: checkBounds(normArgs, tl) args.lazyZip(tl.paramNames).foreach(healTypeParam(_, _, fun.symbol)) case _ => + case _: ValOrDefDef | _: TypeDef => + checkNoLocalRootIn(tree.symbol, tree.symbol.info, tree.symbol.srcPos) case _ => end check end checker diff --git a/tests/neg-custom-args/captures/filevar.scala b/tests/neg-custom-args/captures/filevar.scala index c8280e2ff3b7..34588617c0b8 100644 --- a/tests/neg-custom-args/captures/filevar.scala +++ b/tests/neg-custom-args/captures/filevar.scala @@ -5,7 +5,7 @@ class File: def write(x: String): Unit = ??? class Service: - var file: File^{cap[Service]} = uninitialized + var file: File^{cap[Service]} = uninitialized // error def log = file.write("log") def withFile[T](op: (l: caps.Cap) ?-> (f: File^{l}) => T): T = diff --git a/tests/neg-custom-args/captures/localcaps.check b/tests/neg-custom-args/captures/localcaps.check new file mode 100644 index 000000000000..b09702749d10 --- /dev/null +++ b/tests/neg-custom-args/captures/localcaps.check @@ -0,0 +1,12 @@ +-- Error: tests/neg-custom-args/captures/localcaps.scala:4:12 ---------------------------------------------------------- +4 | def x: C^{cap[d]} = ??? // error + | ^^^^^^ + | `d` does not name an outer definition that represents a capture level +-- Error: tests/neg-custom-args/captures/localcaps.scala:9:47 ---------------------------------------------------------- +9 | private val z2 = identity((x: Int) => (c: C^{cap[z2]}) => x) // error + | ^^^^^^^ + | `z2` does not name an outer definition that represents a capture level +-- Error: tests/neg-custom-args/captures/localcaps.scala:6:6 ----------------------------------------------------------- +6 | def y: C^{cap[C]} = ??? // error + | ^ + | local root (cap[C] : caps.Cap) cannot appear in type of class C diff --git a/tests/neg-custom-args/captures/localcaps.scala b/tests/neg-custom-args/captures/localcaps.scala index f5227bfef96b..049a1ee0d775 100644 --- a/tests/neg-custom-args/captures/localcaps.scala +++ b/tests/neg-custom-args/captures/localcaps.scala @@ -3,7 +3,7 @@ class C: def x: C^{cap[d]} = ??? // error - def y: C^{cap[C]} = ??? // ok + def y: C^{cap[C]} = ??? // error private val z = (c0: caps.Cap) => (x: Int) => (c: C^{cap[C]}) => x // ok private val z2 = identity((x: Int) => (c: C^{cap[z2]}) => x) // error diff --git a/tests/neg-custom-args/captures/pairs.check b/tests/neg-custom-args/captures/pairs.check index 38712469879f..9d1b3a76e164 100644 --- a/tests/neg-custom-args/captures/pairs.check +++ b/tests/neg-custom-args/captures/pairs.check @@ -12,3 +12,11 @@ | Required: Cap^ ->{d} Unit | | longer explanation available when compiling with `-explain` +-- Error: tests/neg-custom-args/captures/pairs.scala:6:8 --------------------------------------------------------------- +6 | def fst: Cap^{cap[Pair]} ->{x} Unit = x // error + | ^ + | local root (cap[Pair] : caps.Cap) cannot appear in type of class Pair +-- Error: tests/neg-custom-args/captures/pairs.scala:7:8 --------------------------------------------------------------- +7 | def snd: Cap^{cap[Pair]} ->{y} Unit = y // error + | ^ + | local root (cap[Pair] : caps.Cap) cannot appear in type of class Pair diff --git a/tests/neg-custom-args/captures/pairs.scala b/tests/neg-custom-args/captures/pairs.scala index 4fc495d60f95..99b27639f729 100644 --- a/tests/neg-custom-args/captures/pairs.scala +++ b/tests/neg-custom-args/captures/pairs.scala @@ -3,8 +3,8 @@ object Monomorphic2: class Pair(x: Cap => Unit, y: Cap => Unit): - def fst: Cap^{cap[Pair]} ->{x} Unit = x - def snd: Cap^{cap[Pair]} ->{y} Unit = y + def fst: Cap^{cap[Pair]} ->{x} Unit = x // error + def snd: Cap^{cap[Pair]} ->{y} Unit = y // error def test(c: Cap, d: Cap) = def f(x: Cap): Unit = if c == x then () diff --git a/tests/neg-custom-args/captures/recursive-leaking-local-cap.scala b/tests/neg-custom-args/captures/recursive-leaking-local-cap.scala new file mode 100644 index 000000000000..0daecafbf9d0 --- /dev/null +++ b/tests/neg-custom-args/captures/recursive-leaking-local-cap.scala @@ -0,0 +1,22 @@ +import language.experimental.captureChecking +trait Cap: + def use: Int = 42 + +def usingCap[sealed T](op: Cap^ => T): T = ??? + +def badTest(): Unit = + def bad(b: Boolean)(c: Cap^): Cap^{cap[bad]} = // error + if b then c + else + val leaked = usingCap[Cap^{cap[bad]}](bad(true)) + leaked.use // boom + c + + usingCap[Unit]: c0 => + bad(false)(c0) + +class Bad: + def foo: Cap^{cap[Bad]} = ??? // error + private def bar: Cap^{cap[Bad]} = ??? // ok + + diff --git a/tests/neg-custom-args/captures/sealed-classes.scala b/tests/neg-custom-args/captures/sealed-classes.scala new file mode 100644 index 000000000000..b8cb0acbf5c5 --- /dev/null +++ b/tests/neg-custom-args/captures/sealed-classes.scala @@ -0,0 +1,21 @@ +abstract class C1[A1]: + def set(x: A1): Unit + def get: A1 + +trait Co[+A]: + def get: A + +class C2[sealed A2] extends C1[A2], Co[A2]: // ok + private var x: A2 = ??? + def set(x: A2): Unit = + this.x = x + def get: A2 = x + +class C3[A3] extends C2[A3] // error + +abstract class C4[sealed A4] extends Co[A4] // ok + +abstract class C5[sealed +A5] extends Co[A5] // ok + +abstract class C6[A6] extends C5[A6] // error + From bb0b77434884758a069d4df19552aed4df9c165f Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 15:20:42 +0100 Subject: [PATCH 10/89] Require array element types to be sealed --- .../src/dotty/tools/dotc/cc/CaptureOps.scala | 6 ++++ .../src/dotty/tools/dotc/cc/CaptureSet.scala | 1 + .../dotty/tools/dotc/cc/CheckCaptures.scala | 31 ++++++++++++++----- .../dotty/tools/dotc/transform/Recheck.scala | 6 ++-- tests/neg-custom-args/captures/buffers.check | 26 ++++++++++++++++ tests/neg-custom-args/captures/buffers.scala | 30 ++++++++++++++++++ .../stdlib/collection/IterableOnce.scala | 19 ++++++------ .../stdlib/collection/Iterator.scala | 2 +- .../stdlib/collection/SeqView.scala | 3 +- .../stdlib/collection/StringOps.scala | 2 +- .../collection/mutable/ArrayBuffer.scala | 4 +-- .../stdlib/collection/mutable/Buffer.scala | 3 +- .../collection/mutable/StringBuilder.scala | 2 +- 13 files changed, 109 insertions(+), 26 deletions(-) create mode 100644 tests/neg-custom-args/captures/buffers.check create mode 100644 tests/neg-custom-args/captures/buffers.scala diff --git a/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala b/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala index dccf07ba199e..0fe79da30ca5 100644 --- a/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala +++ b/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala @@ -206,6 +206,12 @@ extension (tp: Type) case _: TypeRef | _: AppliedType => tp.typeSymbol.hasAnnotation(defn.CapabilityAnnot) case _ => false + def isSealed(using Context): Boolean = tp match + case tp: TypeParamRef => tp.underlying.isSealed + case tp: TypeBounds => tp.hi.hasAnnotation(defn.Caps_SealedAnnot) + case tp: TypeRef => tp.symbol.is(Sealed) || tp.info.isSealed // TODO: drop symbol flag? + case _ => false + /** Drop @retains annotations everywhere */ def dropAllRetains(using Context): Type = // TODO we should drop retains from inferred types before unpickling val tm = new TypeMap: diff --git a/compiler/src/dotty/tools/dotc/cc/CaptureSet.scala b/compiler/src/dotty/tools/dotc/cc/CaptureSet.scala index 2586d449dfd4..7261c760aa01 100644 --- a/compiler/src/dotty/tools/dotc/cc/CaptureSet.scala +++ b/compiler/src/dotty/tools/dotc/cc/CaptureSet.scala @@ -872,6 +872,7 @@ object CaptureSet: upper.isAlwaysEmpty || upper.isConst && upper.elems.size == 1 && upper.elems.contains(r1) if variance > 0 || isExact then upper else if variance < 0 then CaptureSet.empty + else if ctx.mode.is(Mode.Printing) then upper else assert(false, i"trying to add $upper from $r via ${tm.getClass} in a non-variant setting") /** Apply `f` to each element in `xs`, and join result sets with `++` */ diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index c7b282b49dba..3e246c754feb 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -148,7 +148,7 @@ object CheckCaptures: val check = new TypeTraverser: extension (tparam: Symbol) def isParametricIn(carrier: Symbol): Boolean = - val encl = carrier.owner.enclosingMethodOrClass + val encl = carrier.maybeOwner.enclosingMethodOrClass if encl.isClass then tparam.isParametricIn(encl) else def recur(encl: Symbol): Boolean = @@ -160,11 +160,9 @@ object CheckCaptures: def traverse(t: Type) = t.dealiasKeepAnnots match case t: TypeRef => - capt.println(i"disallow $t, $tp, $what, ${t.symbol.is(Sealed)}") + capt.println(i"disallow $t, $tp, $what, ${t.isSealed}") t.info match - case TypeBounds(_, hi) - if !t.symbol.is(Sealed) && !hi.hasAnnotation(defn.Caps_SealedAnnot) - && !t.symbol.isParametricIn(carrier) => + case TypeBounds(_, hi) if !t.isSealed && !t.symbol.isParametricIn(carrier) => if hi.isAny then report.error( em"""$what cannot $have $tp since @@ -543,8 +541,8 @@ class CheckCaptures extends Recheck, SymTransformer: val TypeApply(fn, args) = tree val polyType = atPhase(thisPhase.prev): fn.tpe.widen.asInstanceOf[TypeLambda] - for case (arg: TypeTree, pinfo, pname) <- args.lazyZip(polyType.paramInfos).lazyZip((polyType.paramNames)) do - if pinfo.bounds.hi.hasAnnotation(defn.Caps_SealedAnnot) then + for case (arg: TypeTree, formal, pname) <- args.lazyZip(polyType.paramRefs).lazyZip((polyType.paramNames)) do + if formal.isSealed then def where = if fn.symbol.exists then i" in an argument of ${fn.symbol}" else "" disallowRootCapabilitiesIn(arg.knownType, fn.symbol, i"Sealed type variable $pname", "be instantiated to", @@ -1315,6 +1313,23 @@ class CheckCaptures extends Recheck, SymTransformer: traverseChildren(tp) check.traverse(info) + def checkArraysAreSealedIn(tp: Type, pos: SrcPos)(using Context): Unit = + val check = new TypeTraverser: + def traverse(t: Type): Unit = + t match + case AppliedType(tycon, arg :: Nil) if tycon.typeSymbol == defn.ArrayClass => + if !(pos.span.isSynthetic && ctx.reporter.errorsReported) then + CheckCaptures.disallowRootCapabilitiesIn(arg, NoSymbol, + "Array", "have element type", + "Since arrays are mutable, they have to be treated like variables,\nso their element type must be sealed.", + pos) + traverseChildren(t) + case defn.RefinedFunctionOf(rinfo: MethodType) => + traverse(rinfo) + case _ => + traverseChildren(t) + check.traverse(tp) + /** Perform the following kinds of checks * - Check all explicitly written capturing types for well-formedness using `checkWellFormedPost`. * - Check that arguments of TypeApplys and AppliedTypes conform to their bounds. @@ -1340,6 +1355,8 @@ class CheckCaptures extends Recheck, SymTransformer: case _ => case _: ValOrDefDef | _: TypeDef => checkNoLocalRootIn(tree.symbol, tree.symbol.info, tree.symbol.srcPos) + case tree: TypeTree => + checkArraysAreSealedIn(tree.tpe, tree.srcPos) case _ => end check end checker diff --git a/compiler/src/dotty/tools/dotc/transform/Recheck.scala b/compiler/src/dotty/tools/dotc/transform/Recheck.scala index 9833b3cf177f..b15a58b98b6f 100644 --- a/compiler/src/dotty/tools/dotc/transform/Recheck.scala +++ b/compiler/src/dotty/tools/dotc/transform/Recheck.scala @@ -596,9 +596,9 @@ abstract class Recheck extends Phase, SymTransformer: /** Show tree with rechecked types instead of the types stored in the `.tpe` field */ override def show(tree: untpd.Tree)(using Context): String = - atPhase(thisPhase) { - super.show(addRecheckedTypes.transform(tree.asInstanceOf[tpd.Tree])) - } + atPhase(thisPhase): + withMode(Mode.Printing): + super.show(addRecheckedTypes.transform(tree.asInstanceOf[tpd.Tree])) end Recheck /** A class that can be used to test basic rechecking without any customaization */ diff --git a/tests/neg-custom-args/captures/buffers.check b/tests/neg-custom-args/captures/buffers.check new file mode 100644 index 000000000000..cdb7baa852fb --- /dev/null +++ b/tests/neg-custom-args/captures/buffers.check @@ -0,0 +1,26 @@ +-- Error: tests/neg-custom-args/captures/buffers.scala:11:6 ------------------------------------------------------------ +11 | var elems: Array[A] = new Array[A](10) // error // error + | ^ + | mutable variable elems cannot have type Array[A] since + | that type refers to the type variable A, which is not sealed. +-- Error: tests/neg-custom-args/captures/buffers.scala:16:38 ----------------------------------------------------------- +16 | def make[A: ClassTag](xs: A*) = new ArrayBuffer: // error + | ^^^^^^^^^^^ + | Sealed type variable A cannot be instantiated to box A^? since + | that type refers to the type variable A, which is not sealed. + | This is often caused by a local capability in an argument of constructor ArrayBuffer + | leaking as part of its result. +-- Error: tests/neg-custom-args/captures/buffers.scala:11:13 ----------------------------------------------------------- +11 | var elems: Array[A] = new Array[A](10) // error // error + | ^^^^^^^^ + | Array cannot have element type A since + | that type refers to the type variable A, which is not sealed. + | Since arrays are mutable, they have to be treated like variables, + | so their element type must be sealed. +-- Error: tests/neg-custom-args/captures/buffers.scala:22:9 ------------------------------------------------------------ +22 | val x: Array[A] = new Array[A](10) // error + | ^^^^^^^^ + | Array cannot have element type A since + | that type refers to the type variable A, which is not sealed. + | Since arrays are mutable, they have to be treated like variables, + | so their element type must be sealed. diff --git a/tests/neg-custom-args/captures/buffers.scala b/tests/neg-custom-args/captures/buffers.scala new file mode 100644 index 000000000000..760ddab96ae5 --- /dev/null +++ b/tests/neg-custom-args/captures/buffers.scala @@ -0,0 +1,30 @@ +import reflect.ClassTag + +class Buffer[A] + +class ArrayBuffer[sealed A: ClassTag] extends Buffer[A]: + var elems: Array[A] = new Array[A](10) + def add(x: A): this.type = ??? + def at(i: Int): A = ??? + +class ArrayBufferBAD[A: ClassTag] extends Buffer[A]: + var elems: Array[A] = new Array[A](10) // error // error + def add(x: A): this.type = ??? + def at(i: Int): A = ??? + +object ArrayBuffer: + def make[A: ClassTag](xs: A*) = new ArrayBuffer: // error + elems = xs.toArray + def apply[sealed A: ClassTag](xs: A*) = new ArrayBuffer: + elems = xs.toArray // ok + +class EncapsArray[A: ClassTag]: + val x: Array[A] = new Array[A](10) // error + + + + + + + + diff --git a/tests/pos-special/stdlib/collection/IterableOnce.scala b/tests/pos-special/stdlib/collection/IterableOnce.scala index 3886d7dccb95..a88be4943c58 100644 --- a/tests/pos-special/stdlib/collection/IterableOnce.scala +++ b/tests/pos-special/stdlib/collection/IterableOnce.scala @@ -165,7 +165,7 @@ final class IterableOnceExtensionMethods[A](private val it: IterableOnce[A]) ext def toBuffer[sealed B >: A]: mutable.Buffer[B] = mutable.ArrayBuffer.from(it) @deprecated("Use .iterator.toArray", "2.13.0") - def toArray[B >: A: ClassTag]: Array[B] = it match { + def toArray[sealed B >: A: ClassTag]: Array[B] = it match { case it: Iterable[B] => it.toArray[B] case _ => it.iterator.toArray[B] } @@ -272,10 +272,11 @@ object IterableOnce { math.max(math.min(math.min(len, srcLen), destLen - start), 0) /** Calls `copyToArray` on the given collection, regardless of whether or not it is an `Iterable`. */ - @inline private[collection] def copyElemsToArray[A, B >: A](elems: IterableOnce[A]^, - xs: Array[B], - start: Int = 0, - len: Int = Int.MaxValue): Int = + @inline private[collection] def copyElemsToArray[A, sealed B >: A]( + elems: IterableOnce[A]^, + xs: Array[B], + start: Int = 0, + len: Int = Int.MaxValue): Int = elems match { case src: Iterable[A] => src.copyToArray[B](xs, start, len) case src => src.iterator.copyToArray[B](xs, start, len) @@ -889,7 +890,7 @@ trait IterableOnceOps[+A, +CC[_], +C] extends Any { this: IterableOnce[A]^ => * @note Reuse: $consumesIterator */ @deprecatedOverriding("This should always forward to the 3-arg version of this method", since = "2.13.4") - def copyToArray[B >: A](xs: Array[B]): Int = copyToArray(xs, 0, Int.MaxValue) + def copyToArray[sealed B >: A](xs: Array[B]): Int = copyToArray(xs, 0, Int.MaxValue) /** Copy elements to an array, returning the number of elements written. * @@ -906,7 +907,7 @@ trait IterableOnceOps[+A, +CC[_], +C] extends Any { this: IterableOnce[A]^ => * @note Reuse: $consumesIterator */ @deprecatedOverriding("This should always forward to the 3-arg version of this method", since = "2.13.4") - def copyToArray[B >: A](xs: Array[B], start: Int): Int = copyToArray(xs, start, Int.MaxValue) + def copyToArray[sealed B >: A](xs: Array[B], start: Int): Int = copyToArray(xs, start, Int.MaxValue) /** Copy elements to an array, returning the number of elements written. * @@ -923,7 +924,7 @@ trait IterableOnceOps[+A, +CC[_], +C] extends Any { this: IterableOnce[A]^ => * * @note Reuse: $consumesIterator */ - def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = { val it = iterator var i = start val end = start + math.min(len, xs.length - start) @@ -1318,7 +1319,7 @@ trait IterableOnceOps[+A, +CC[_], +C] extends Any { this: IterableOnce[A]^ => * * Implementation note: DO NOT call [[Array.from]] from this method. */ - def toArray[B >: A: ClassTag]: Array[B] = + def toArray[sealed B >: A: ClassTag]: Array[B] = if (knownSize >= 0) { val destination = new Array[B](knownSize) copyToArray(destination, 0) diff --git a/tests/pos-special/stdlib/collection/Iterator.scala b/tests/pos-special/stdlib/collection/Iterator.scala index 0c96aa35501b..68ea4f76c249 100644 --- a/tests/pos-special/stdlib/collection/Iterator.scala +++ b/tests/pos-special/stdlib/collection/Iterator.scala @@ -259,7 +259,7 @@ trait Iterator[+A] extends IterableOnce[A] with IterableOnceOps[A, Iterator, Ite } // segment must have data, and must be complete unless they allow partial val ok = index > 0 && (partial || index == size) - if (ok) buffer = builder.result().asInstanceOf[Array[B]] + if (ok) buffer = builder.result().asInstanceOf[Array[B @uncheckedCaptures]] else prev = null ok } diff --git a/tests/pos-special/stdlib/collection/SeqView.scala b/tests/pos-special/stdlib/collection/SeqView.scala index f8f4f1e199de..a4ca1143f8b4 100644 --- a/tests/pos-special/stdlib/collection/SeqView.scala +++ b/tests/pos-special/stdlib/collection/SeqView.scala @@ -16,6 +16,7 @@ package collection import scala.annotation.nowarn import language.experimental.captureChecking import caps.unsafe.unsafeAssumePure +import scala.annotation.unchecked.uncheckedCaptures /** !!! Scala 2 difference: Need intermediate trait SeqViewOps to collect the * necessary functionality over which SeqViews are defined, and at the same @@ -195,7 +196,7 @@ object SeqView { // contains items of another type, we'd get a CCE anyway) // - the cast doesn't actually do anything in the runtime because the // type of A is not known and Array[_] is Array[AnyRef] - immutable.ArraySeq.unsafeWrapArray(arr.asInstanceOf[Array[A]]) + immutable.ArraySeq.unsafeWrapArray(arr.asInstanceOf[Array[A @uncheckedCaptures]]) } } evaluated = true diff --git a/tests/pos-special/stdlib/collection/StringOps.scala b/tests/pos-special/stdlib/collection/StringOps.scala index f570531def98..3e3e2f8d872e 100644 --- a/tests/pos-special/stdlib/collection/StringOps.scala +++ b/tests/pos-special/stdlib/collection/StringOps.scala @@ -964,7 +964,7 @@ final class StringOps(private val s: String) extends AnyVal { else if (s.equalsIgnoreCase("false")) false else throw new IllegalArgumentException("For input string: \""+s+"\"") - def toArray[B >: Char](implicit tag: ClassTag[B]): Array[B] = + def toArray[sealed B >: Char](implicit tag: ClassTag[B]): Array[B] = if (tag == ClassTag.Char) s.toCharArray.asInstanceOf[Array[B]] else new WrappedString(s).toArray[B] diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala b/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala index e0b3edc54690..8fa1e6edd566 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArrayBuffer.scala @@ -241,7 +241,7 @@ class ArrayBuffer[sealed A] private (initialElements: Array[AnyRef], initialSize @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") override protected[this] def stringPrefix = "ArrayBuffer" - override def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + override def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = { val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) if(copied > 0) { Array.copy(array, 0, xs, start, copied) @@ -258,7 +258,7 @@ class ArrayBuffer[sealed A] private (initialElements: Array[AnyRef], initialSize override def sortInPlace[B >: A]()(implicit ord: Ordering[B]): this.type = { if (length > 1) { mutationCount += 1 - scala.util.Sorting.stableSort(array.asInstanceOf[Array[B]], 0, length) + scala.util.Sorting.stableSort(array.asInstanceOf[Array[B @uncheckedCaptures]], 0, length) } this } diff --git a/tests/pos-special/stdlib/collection/mutable/Buffer.scala b/tests/pos-special/stdlib/collection/mutable/Buffer.scala index f5e6ce66c99a..0f472dc9ac82 100644 --- a/tests/pos-special/stdlib/collection/mutable/Buffer.scala +++ b/tests/pos-special/stdlib/collection/mutable/Buffer.scala @@ -15,6 +15,7 @@ package mutable import scala.annotation.nowarn import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures /** A `Buffer` is a growable and shrinkable `Seq`. */ @@ -185,7 +186,7 @@ trait IndexedBuffer[A] extends IndexedSeq[A] // There's scope for a better implementation which copies elements in place. var i = 0 val s = size - val newElems = new Array[IterableOnce[A]^](s) + val newElems = new Array[(IterableOnce[A]^) @uncheckedCaptures](s) while (i < s) { newElems(i) = f(this(i)); i += 1 } clear() i = 0 diff --git a/tests/pos-special/stdlib/collection/mutable/StringBuilder.scala b/tests/pos-special/stdlib/collection/mutable/StringBuilder.scala index c7859214821d..5320fa1dabb0 100644 --- a/tests/pos-special/stdlib/collection/mutable/StringBuilder.scala +++ b/tests/pos-special/stdlib/collection/mutable/StringBuilder.scala @@ -110,7 +110,7 @@ final class StringBuilder(val underlying: java.lang.StringBuilder) extends Abstr override def toString: String = result() - override def toArray[B >: Char](implicit ct: scala.reflect.ClassTag[B]) = + override def toArray[sealed B >: Char](implicit ct: scala.reflect.ClassTag[B]) = ct.runtimeClass match { case java.lang.Character.TYPE => toCharArray.asInstanceOf[Array[B]] case _ => super.toArray From 6b5e4948b6977591e168692e15a5193e3c86cafb Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 15:26:43 +0100 Subject: [PATCH 11/89] Add ArrayBuilder.scala in unchanged form to stdlib --- .../collection/mutable/ArrayBuilder.scala | 522 ++++++++++++++++++ 1 file changed, 522 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala b/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala new file mode 100644 index 000000000000..454527bcdebd --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala @@ -0,0 +1,522 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.reflect.ClassTag + +/** A builder class for arrays. + * + * @tparam T the type of the elements for the builder. + */ +@SerialVersionUID(3L) +sealed abstract class ArrayBuilder[T] + extends ReusableBuilder[T, Array[T]] + with Serializable { + protected[this] var capacity: Int = 0 + protected[this] def elems: Array[T] + protected var size: Int = 0 + + def length: Int = size + + override def knownSize: Int = size + + protected[this] final def ensureSize(size: Int): Unit = { + if (capacity < size || capacity == 0) { + var newsize = if (capacity == 0) 16 else capacity * 2 + while (newsize < size) newsize *= 2 + resize(newsize) + } + } + + override final def sizeHint(size: Int): Unit = + if (capacity < size) resize(size) + + def clear(): Unit = size = 0 + + protected[this] def resize(size: Int): Unit + + /** Add all elements of an array */ + def addAll(xs: Array[_ <: T]): this.type = addAll(xs, 0, xs.length) + + /** Add a slice of an array */ + def addAll(xs: Array[_ <: T], offset: Int, length: Int): this.type = { + ensureSize(this.size + length) + Array.copy(xs, offset, elems, this.size, length) + size += length + this + } + + override def addAll(xs: IterableOnce[T]): this.type = { + val k = xs.knownSize + if (k > 0) { + ensureSize(this.size + k) + val actual = IterableOnce.copyElemsToArray(xs, elems, this.size) + if (actual != k) throw new IllegalStateException(s"Copied $actual of $k") + size += k + } else if (k < 0) super.addAll(xs) + this + } +} + +/** A companion object for array builders. + */ +object ArrayBuilder { + + /** Creates a new arraybuilder of type `T`. + * + * @tparam T type of the elements for the array builder, with a `ClassTag` context bound. + * @return a new empty array builder. + */ + @inline def make[T: ClassTag]: ArrayBuilder[T] = { + val tag = implicitly[ClassTag[T]] + tag.runtimeClass match { + case java.lang.Byte.TYPE => new ArrayBuilder.ofByte().asInstanceOf[ArrayBuilder[T]] + case java.lang.Short.TYPE => new ArrayBuilder.ofShort().asInstanceOf[ArrayBuilder[T]] + case java.lang.Character.TYPE => new ArrayBuilder.ofChar().asInstanceOf[ArrayBuilder[T]] + case java.lang.Integer.TYPE => new ArrayBuilder.ofInt().asInstanceOf[ArrayBuilder[T]] + case java.lang.Long.TYPE => new ArrayBuilder.ofLong().asInstanceOf[ArrayBuilder[T]] + case java.lang.Float.TYPE => new ArrayBuilder.ofFloat().asInstanceOf[ArrayBuilder[T]] + case java.lang.Double.TYPE => new ArrayBuilder.ofDouble().asInstanceOf[ArrayBuilder[T]] + case java.lang.Boolean.TYPE => new ArrayBuilder.ofBoolean().asInstanceOf[ArrayBuilder[T]] + case java.lang.Void.TYPE => new ArrayBuilder.ofUnit().asInstanceOf[ArrayBuilder[T]] + case _ => new ArrayBuilder.ofRef[T with AnyRef]()(tag.asInstanceOf[ClassTag[T with AnyRef]]).asInstanceOf[ArrayBuilder[T]] + } + } + + /** A class for array builders for arrays of reference types. + * + * This builder can be reused. + * + * @tparam T type of elements for the array builder, subtype of `AnyRef` with a `ClassTag` context bound. + */ + @SerialVersionUID(3L) + final class ofRef[T <: AnyRef](implicit ct: ClassTag[T]) extends ArrayBuilder[T] { + + protected var elems: Array[T] = _ + + private def mkArray(size: Int): Array[T] = { + if (capacity == size && capacity > 0) elems + else if (elems eq null) new Array[T](size) + else java.util.Arrays.copyOf[T](elems, size) + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: T): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[T] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def clear(): Unit = { + super.clear() + if(elems ne null) java.util.Arrays.fill(elems.asInstanceOf[Array[AnyRef]], null) + } + + override def equals(other: Any): Boolean = other match { + case x: ofRef[_] => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofRef" + } + + /** A class for array builders for arrays of `byte`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofByte extends ArrayBuilder[Byte] { + + protected var elems: Array[Byte] = _ + + private def mkArray(size: Int): Array[Byte] = { + val newelems = new Array[Byte](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Byte): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Byte] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofByte => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofByte" + } + + /** A class for array builders for arrays of `short`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofShort extends ArrayBuilder[Short] { + + protected var elems: Array[Short] = _ + + private def mkArray(size: Int): Array[Short] = { + val newelems = new Array[Short](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Short): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Short] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofShort => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofShort" + } + + /** A class for array builders for arrays of `char`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofChar extends ArrayBuilder[Char] { + + protected var elems: Array[Char] = _ + + private def mkArray(size: Int): Array[Char] = { + val newelems = new Array[Char](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Char): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Char] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofChar => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofChar" + } + + /** A class for array builders for arrays of `int`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofInt extends ArrayBuilder[Int] { + + protected var elems: Array[Int] = _ + + private def mkArray(size: Int): Array[Int] = { + val newelems = new Array[Int](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Int): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Int] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofInt => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofInt" + } + + /** A class for array builders for arrays of `long`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofLong extends ArrayBuilder[Long] { + + protected var elems: Array[Long] = _ + + private def mkArray(size: Int): Array[Long] = { + val newelems = new Array[Long](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Long): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Long] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofLong => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofLong" + } + + /** A class for array builders for arrays of `float`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofFloat extends ArrayBuilder[Float] { + + protected var elems: Array[Float] = _ + + private def mkArray(size: Int): Array[Float] = { + val newelems = new Array[Float](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Float): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Float] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofFloat => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofFloat" + } + + /** A class for array builders for arrays of `double`s. It can be reused. */ + @SerialVersionUID(3L) + final class ofDouble extends ArrayBuilder[Double] { + + protected var elems: Array[Double] = _ + + private def mkArray(size: Int): Array[Double] = { + val newelems = new Array[Double](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Double): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Double] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofDouble => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofDouble" + } + + /** A class for array builders for arrays of `boolean`s. It can be reused. */ + @SerialVersionUID(3L) + class ofBoolean extends ArrayBuilder[Boolean] { + + protected var elems: Array[Boolean] = _ + + private def mkArray(size: Int): Array[Boolean] = { + val newelems = new Array[Boolean](size) + if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) + newelems + } + + protected[this] def resize(size: Int): Unit = { + elems = mkArray(size) + capacity = size + } + + def addOne(elem: Boolean): this.type = { + ensureSize(size + 1) + elems(size) = elem + size += 1 + this + } + + def result(): Array[Boolean] = { + if (capacity != 0 && capacity == size) { + capacity = 0 + val res = elems + elems = null + res + } + else mkArray(size) + } + + override def equals(other: Any): Boolean = other match { + case x: ofBoolean => (size == x.size) && (elems == x.elems) + case _ => false + } + + override def toString = "ArrayBuilder.ofBoolean" + } + + /** A class for array builders for arrays of `Unit` type. It can be reused. */ + @SerialVersionUID(3L) + final class ofUnit extends ArrayBuilder[Unit] { + + protected def elems: Array[Unit] = throw new UnsupportedOperationException() + + def addOne(elem: Unit): this.type = { + size += 1 + this + } + + override def addAll(xs: IterableOnce[Unit]): this.type = { + size += xs.iterator.size + this + } + + override def addAll(xs: Array[_ <: Unit], offset: Int, length: Int): this.type = { + size += length + this + } + + def result() = { + val ans = new Array[Unit](size) + var i = 0 + while (i < size) { ans(i) = (); i += 1 } + ans + } + + override def equals(other: Any): Boolean = other match { + case x: ofUnit => (size == x.size) + case _ => false + } + + protected[this] def resize(size: Int): Unit = () + + override def toString = "ArrayBuilder.ofUnit" + } +} From 609549c43875e3c40c6a1a99f826f76e67c348c1 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 15:28:59 +0100 Subject: [PATCH 12/89] Make ArrayBuilder capture checked --- .../stdlib/collection/mutable/ArrayBuilder.scala | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala b/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala index 454527bcdebd..0620d3d23061 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArrayBuilder.scala @@ -13,6 +13,7 @@ package scala.collection package mutable +import language.experimental.captureChecking import scala.reflect.ClassTag /** A builder class for arrays. @@ -20,7 +21,7 @@ import scala.reflect.ClassTag * @tparam T the type of the elements for the builder. */ @SerialVersionUID(3L) -sealed abstract class ArrayBuilder[T] +sealed abstract class ArrayBuilder[sealed T] extends ReusableBuilder[T, Array[T]] with Serializable { protected[this] var capacity: Int = 0 @@ -57,7 +58,7 @@ sealed abstract class ArrayBuilder[T] this } - override def addAll(xs: IterableOnce[T]): this.type = { + override def addAll(xs: IterableOnce[T]^): this.type = { val k = xs.knownSize if (k > 0) { ensureSize(this.size + k) @@ -493,7 +494,7 @@ object ArrayBuilder { this } - override def addAll(xs: IterableOnce[Unit]): this.type = { + override def addAll(xs: IterableOnce[Unit]^): this.type = { size += xs.iterator.size this } From d76f092e26ba3233a00df1b4e93d99a46dae4327 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 15:30:11 +0100 Subject: [PATCH 13/89] Add ArrayDeque.scala in unchanged for to stdlib --- .../collection/mutable/ArrayDeque.scala | 645 ++++++++++++++++++ 1 file changed, 645 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala b/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala new file mode 100644 index 000000000000..205e1607f824 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala @@ -0,0 +1,645 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.annotation.nowarn +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.reflect.ClassTag + +/** An implementation of a double-ended queue that internally uses a resizable circular buffer. + * + * Append, prepend, removeHead, removeLast and random-access (indexed-lookup and indexed-replacement) + * take amortized constant time. In general, removals and insertions at i-th index are O(min(i, n-i)) + * and thus insertions and removals from end/beginning are fast. + * + * @note Subclasses ''must'' override the `ofArray` protected method to return a more specific type. + * + * @tparam A the type of this ArrayDeque's elements. + * + * @define Coll `mutable.ArrayDeque` + * @define coll array deque + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +class ArrayDeque[A] protected ( + protected var array: Array[AnyRef], + private[ArrayDeque] var start: Int, + private[ArrayDeque] var end: Int +) extends AbstractBuffer[A] + with IndexedBuffer[A] + with IndexedSeqOps[A, ArrayDeque, ArrayDeque[A]] + with StrictOptimizedSeqOps[A, ArrayDeque, ArrayDeque[A]] + with IterableFactoryDefaults[A, ArrayDeque] + with ArrayDequeOps[A, ArrayDeque, ArrayDeque[A]] + with Cloneable[ArrayDeque[A]] + with DefaultSerializable { + + reset(array, start, end) + + private[this] def reset(array: Array[AnyRef], start: Int, end: Int) = { + assert((array.length & (array.length - 1)) == 0, s"Array.length must be power of 2") + requireBounds(idx = start, until = array.length) + requireBounds(idx = end, until = array.length) + this.array = array + this.start = start + this.end = end + } + + def this(initialSize: Int = ArrayDeque.DefaultInitialSize) = this(ArrayDeque.alloc(initialSize), start = 0, end = 0) + + override def knownSize: Int = super[IndexedSeqOps].knownSize + + // No-Op override to allow for more efficient stepper in a minor release. + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = super.stepper(shape) + + def apply(idx: Int): A = { + requireBounds(idx) + _get(idx) + } + + def update(idx: Int, elem: A): Unit = { + requireBounds(idx) + _set(idx, elem) + } + + def addOne(elem: A): this.type = { + ensureSize(length + 1) + appendAssumingCapacity(elem) + } + + def prepend(elem: A): this.type = { + ensureSize(length + 1) + prependAssumingCapacity(elem) + } + + @inline private[ArrayDeque] def appendAssumingCapacity(elem: A): this.type = { + array(end) = elem.asInstanceOf[AnyRef] + end = end_+(1) + this + } + + @inline private[ArrayDeque] def prependAssumingCapacity(elem: A): this.type = { + start = start_-(1) + array(start) = elem.asInstanceOf[AnyRef] + this + } + + override def prependAll(elems: IterableOnce[A]): this.type = { + val it = elems.iterator + if (it.nonEmpty) { + val n = length + // The following code resizes the current collection at most once and traverses elems at most twice + elems.knownSize match { + // Size is too expensive to compute AND we can traverse it only once - can't do much but retry with an IndexedSeq + case srcLength if srcLength < 0 => prependAll(it.to(IndexedSeq: Factory[A, IndexedSeq[A]] /* type ascription needed by Dotty */)) + + // We know for sure we need to resize to hold everything, might as well resize and memcopy upfront + case srcLength if mustGrow(srcLength + n) => + val finalLength = srcLength + n + val array2 = ArrayDeque.alloc(finalLength) + it.copyToArray(array2.asInstanceOf[Array[A]]) + copySliceToArray(srcStart = 0, dest = array2, destStart = srcLength, maxItems = n) + reset(array = array2, start = 0, end = finalLength) + + // Just fill up from (start - srcLength) to (start - 1) and move back start + case srcLength => + // Optimized version of `elems.zipWithIndex.foreach((elem, i) => _set(i - srcLength, elem))` + var i = 0 + while(i < srcLength) { + _set(i - srcLength, it.next()) + i += 1 + } + start = start_-(srcLength) + } + } + this + } + + override def addAll(elems: IterableOnce[A]): this.type = { + elems.knownSize match { + case srcLength if srcLength > 0 => + ensureSize(srcLength + length) + elems.iterator.foreach(appendAssumingCapacity) + case _ => elems.iterator.foreach(+=) + } + this + } + + def insert(idx: Int, elem: A): Unit = { + requireBounds(idx, length+1) + val n = length + if (idx == 0) { + prepend(elem) + } else if (idx == n) { + addOne(elem) + } else { + val finalLength = n + 1 + if (mustGrow(finalLength)) { + val array2 = ArrayDeque.alloc(finalLength) + copySliceToArray(srcStart = 0, dest = array2, destStart = 0, maxItems = idx) + array2(idx) = elem.asInstanceOf[AnyRef] + copySliceToArray(srcStart = idx, dest = array2, destStart = idx + 1, maxItems = n) + reset(array = array2, start = 0, end = finalLength) + } else if (n <= idx * 2) { + var i = n - 1 + while(i >= idx) { + _set(i + 1, _get(i)) + i -= 1 + } + end = end_+(1) + i += 1 + _set(i, elem) + } else { + var i = 0 + while(i < idx) { + _set(i - 1, _get(i)) + i += 1 + } + start = start_-(1) + _set(i, elem) + } + } + } + + def insertAll(idx: Int, elems: IterableOnce[A]): Unit = { + requireBounds(idx, length+1) + val n = length + if (idx == 0) { + prependAll(elems) + } else if (idx == n) { + addAll(elems) + } else { + // Get both an iterator and the length of the source (by copying the source to an IndexedSeq if needed) + val (it, srcLength) = { + val _srcLength = elems.knownSize + if (_srcLength >= 0) (elems.iterator, _srcLength) + else { + val indexed = IndexedSeq.from(elems) + (indexed.iterator, indexed.size) + } + } + if (it.nonEmpty) { + val finalLength = srcLength + n + // Either we resize right away or move prefix left or suffix right + if (mustGrow(finalLength)) { + val array2 = ArrayDeque.alloc(finalLength) + copySliceToArray(srcStart = 0, dest = array2, destStart = 0, maxItems = idx) + it.copyToArray(array2.asInstanceOf[Array[A]], idx) + copySliceToArray(srcStart = idx, dest = array2, destStart = idx + srcLength, maxItems = n) + reset(array = array2, start = 0, end = finalLength) + } else if (2*idx >= n) { // Cheaper to shift the suffix right + var i = n - 1 + while(i >= idx) { + _set(i + srcLength, _get(i)) + i -= 1 + } + end = end_+(srcLength) + while(it.hasNext) { + i += 1 + _set(i, it.next()) + } + } else { // Cheaper to shift prefix left + var i = 0 + while(i < idx) { + _set(i - srcLength, _get(i)) + i += 1 + } + start = start_-(srcLength) + while(it.hasNext) { + _set(i, it.next()) + i += 1 + } + } + } + } + } + + def remove(idx: Int, count: Int): Unit = { + if (count > 0) { + requireBounds(idx) + val n = length + val removals = Math.min(n - idx, count) + val finalLength = n - removals + val suffixStart = idx + removals + // If we know we can resize after removing, do it right away using arrayCopy + // Else, choose the shorter: either move the prefix (0 until idx) right OR the suffix (idx+removals until n) left + if (shouldShrink(finalLength)) { + val array2 = ArrayDeque.alloc(finalLength) + copySliceToArray(srcStart = 0, dest = array2, destStart = 0, maxItems = idx) + copySliceToArray(srcStart = suffixStart, dest = array2, destStart = idx, maxItems = n) + reset(array = array2, start = 0, end = finalLength) + } else if (2*idx <= finalLength) { // Cheaper to move the prefix right + var i = suffixStart - 1 + while(i >= removals) { + _set(i, _get(i - removals)) + i -= 1 + } + while(i >= 0) { + _set(i, null.asInstanceOf[A]) + i -= 1 + } + start = start_+(removals) + } else { // Cheaper to move the suffix left + var i = idx + while(i < finalLength) { + _set(i, _get(i + removals)) + i += 1 + } + while(i < n) { + _set(i, null.asInstanceOf[A]) + i += 1 + } + end = end_-(removals) + } + } else { + require(count == 0, s"removing negative number of elements: $count") + } + } + + def remove(idx: Int): A = { + val elem = this(idx) + remove(idx, 1) + elem + } + + override def subtractOne(elem: A): this.type = { + val idx = indexOf(elem) + if (idx >= 0) remove(idx, 1) //TODO: SeqOps should be fluent API + this + } + + /** + * + * @param resizeInternalRepr If this is set, resize the internal representation to reclaim space once in a while + * @return + */ + def removeHeadOption(resizeInternalRepr: Boolean = false): Option[A] = + if (isEmpty) None else Some(removeHeadAssumingNonEmpty(resizeInternalRepr)) + + /** + * Unsafely remove the first element (throws exception when empty) + * See also removeHeadOption() + * + * @param resizeInternalRepr If this is set, resize the internal representation to reclaim space once in a while + * @throws NoSuchElementException when empty + * @return + */ + def removeHead(resizeInternalRepr: Boolean = false): A = + if (isEmpty) throw new NoSuchElementException(s"empty collection") else removeHeadAssumingNonEmpty(resizeInternalRepr) + + @inline private[this] def removeHeadAssumingNonEmpty(resizeInternalRepr: Boolean = false): A = { + val elem = array(start) + array(start) = null + start = start_+(1) + if (resizeInternalRepr) resize(length) + elem.asInstanceOf[A] + } + + /** + * + * @param resizeInternalRepr If this is set, resize the internal representation to reclaim space once in a while + * @return + */ + def removeLastOption(resizeInternalRepr: Boolean = false): Option[A] = + if (isEmpty) None else Some(removeLastAssumingNonEmpty(resizeInternalRepr)) + + /** + * Unsafely remove the last element (throws exception when empty) + * See also removeLastOption() + * + * @param resizeInternalRepr If this is set, resize the internal representation to reclaim space once in a while + * @throws NoSuchElementException when empty + * @return + */ + def removeLast(resizeInternalRepr: Boolean = false): A = + if (isEmpty) throw new NoSuchElementException(s"empty collection") else removeLastAssumingNonEmpty(resizeInternalRepr) + + @`inline` private[this] def removeLastAssumingNonEmpty(resizeInternalRepr: Boolean = false): A = { + end = end_-(1) + val elem = array(end) + array(end) = null + if (resizeInternalRepr) resize(length) + elem.asInstanceOf[A] + } + + /** + * Remove all elements from this collection and return the elements while emptying this data structure + * @return + */ + def removeAll(): scala.collection.immutable.Seq[A] = { + val elems = scala.collection.immutable.Seq.newBuilder[A] + elems.sizeHint(length) + while(nonEmpty) { + elems += removeHeadAssumingNonEmpty() + } + elems.result() + } + + /** + * Remove all elements from this collection and return the elements in reverse while emptying this data structure + * @return + */ + def removeAllReverse(): scala.collection.immutable.Seq[A] = { + val elems = scala.collection.immutable.Seq.newBuilder[A] + elems.sizeHint(length) + while(nonEmpty) { + elems += removeLastAssumingNonEmpty() + } + elems.result() + } + + /** + * Returns and removes all elements from the left of this queue which satisfy the given predicate + * + * @param f the predicate used for choosing elements + * @return + */ + def removeHeadWhile(f: A => Boolean): scala.collection.immutable.Seq[A] = { + val elems = scala.collection.immutable.Seq.newBuilder[A] + while(headOption.exists(f)) { + elems += removeHeadAssumingNonEmpty() + } + elems.result() + } + + /** + * Returns and removes all elements from the right of this queue which satisfy the given predicate + * + * @param f the predicate used for choosing elements + * @return + */ + def removeLastWhile(f: A => Boolean): scala.collection.immutable.Seq[A] = { + val elems = scala.collection.immutable.Seq.newBuilder[A] + while(lastOption.exists(f)) { + elems += removeLastAssumingNonEmpty() + } + elems.result() + } + + /** Returns the first element which satisfies the given predicate after or at some start index + * and removes this element from the collections + * + * @param p the predicate used for choosing the first element + * @param from the start index + * @return the first element of the queue for which p yields true + */ + def removeFirst(p: A => Boolean, from: Int = 0): Option[A] = { + val i = indexWhere(p, from) + if (i < 0) None else Some(remove(i)) + } + + /** Returns all elements in this collection which satisfy the given predicate + * and removes those elements from this collections. + * + * @param p the predicate used for choosing elements + * @return a sequence of all elements in the queue for which + * p yields true. + */ + def removeAll(p: A => Boolean): scala.collection.immutable.Seq[A] = { + val res = scala.collection.immutable.Seq.newBuilder[A] + var i, j = 0 + while (i < size) { + if (p(this(i))) { + res += this(i) + } else { + if (i != j) { + this(j) = this(i) + } + j += 1 + } + i += 1 + } + if (i != j) takeInPlace(j) + res.result() + } + + @inline def ensureSize(hint: Int) = if (hint > length && mustGrow(hint)) resize(hint) + + def length = end_-(start) + + override def isEmpty = start == end + + override protected def klone(): ArrayDeque[A] = new ArrayDeque(array.clone(), start = start, end = end) + + override def iterableFactory: SeqFactory[ArrayDeque] = ArrayDeque + + /** + * Note: This does not actually resize the internal representation. + * See clearAndShrink if you want to also resize internally + */ + def clear(): Unit = { + while(nonEmpty) { + removeHeadAssumingNonEmpty() + } + } + + /** + * Clears this buffer and shrinks to @param size + * + * @param size + * @return + */ + def clearAndShrink(size: Int = ArrayDeque.DefaultInitialSize): this.type = { + reset(array = ArrayDeque.alloc(size), start = 0, end = 0) + this + } + + protected def ofArray(array: Array[AnyRef], end: Int): ArrayDeque[A] = + new ArrayDeque[A](array, start = 0, end) + + override def copyToArray[B >: A](dest: Array[B], destStart: Int, len: Int): Int = { + val copied = IterableOnce.elemsToCopyToArray(length, dest.length, destStart, len) + if (copied > 0) { + copySliceToArray(srcStart = 0, dest = dest, destStart = destStart, maxItems = len) + } + copied + } + + override def toArray[B >: A: ClassTag]: Array[B] = + copySliceToArray(srcStart = 0, dest = new Array[B](length), destStart = 0, maxItems = length) + + /** + * Trims the capacity of this ArrayDeque's instance to be the current size + */ + def trimToSize(): Unit = resize(length) + + // Utils for common modular arithmetic: + @inline protected def start_+(idx: Int) = (start + idx) & (array.length - 1) + @inline private[this] def start_-(idx: Int) = (start - idx) & (array.length - 1) + @inline private[this] def end_+(idx: Int) = (end + idx) & (array.length - 1) + @inline private[this] def end_-(idx: Int) = (end - idx) & (array.length - 1) + + // Note: here be overflow dragons! This is used for int overflow + // assumptions in resize(). Use caution changing. + @inline private[this] def mustGrow(len: Int) = { + len >= array.length + } + + // Assumes that 0 <= len < array.length! + @inline private[this] def shouldShrink(len: Int) = { + // To avoid allocation churn, only shrink when array is large + // and less than 2/5 filled. + array.length > ArrayDeque.StableSize && array.length - len - (len >> 1) > len + } + + // Assumes that 0 <= len < array.length! + @inline private[this] def canShrink(len: Int) = { + array.length > ArrayDeque.DefaultInitialSize && array.length - len > len + } + + @inline private[this] def _get(idx: Int): A = array(start_+(idx)).asInstanceOf[A] + + @inline private[this] def _set(idx: Int, elem: A) = array(start_+(idx)) = elem.asInstanceOf[AnyRef] + + // Assumes that 0 <= len. + private[this] def resize(len: Int) = if (mustGrow(len) || canShrink(len)) { + val n = length + val array2 = copySliceToArray(srcStart = 0, dest = ArrayDeque.alloc(len), destStart = 0, maxItems = n) + reset(array = array2, start = 0, end = n) + } + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "ArrayDeque" +} + +/** + * $factoryInfo + * @define coll array deque + * @define Coll `ArrayDeque` + */ +@SerialVersionUID(3L) +object ArrayDeque extends StrictOptimizedSeqFactory[ArrayDeque] { + + def from[B](coll: collection.IterableOnce[B]): ArrayDeque[B] = { + val s = coll.knownSize + if (s >= 0) { + val array = alloc(s) + val actual = IterableOnce.copyElemsToArray(coll, array.asInstanceOf[Array[Any]]) + if (actual != s) throw new IllegalStateException(s"Copied $actual of $s") + new ArrayDeque[B](array, start = 0, end = s) + } else new ArrayDeque[B]() ++= coll + } + + def newBuilder[A]: Builder[A, ArrayDeque[A]] = + new GrowableBuilder[A, ArrayDeque[A]](empty) { + override def sizeHint(size: Int): Unit = { + elems.ensureSize(size) + } + } + + def empty[A]: ArrayDeque[A] = new ArrayDeque[A]() + + final val DefaultInitialSize = 16 + + /** + * We try to not repeatedly resize arrays smaller than this + */ + private[ArrayDeque] final val StableSize = 128 + + /** + * Allocates an array whose size is next power of 2 > `len` + * Largest possible len is 1<<30 - 1 + * + * @param len + * @return + */ + private[mutable] def alloc(len: Int) = { + require(len >= 0, s"Non-negative array size required") + val size = (1 << 31) >>> java.lang.Integer.numberOfLeadingZeros(len) << 1 + require(size >= 0, s"ArrayDeque too big - cannot allocate ArrayDeque of length $len") + new Array[AnyRef](Math.max(size, DefaultInitialSize)) + } +} + +trait ArrayDequeOps[A, +CC[_], +C <: AnyRef] extends StrictOptimizedSeqOps[A, CC, C] { + protected def array: Array[AnyRef] + + final override def clone(): C = klone() + + protected def klone(): C + + protected def ofArray(array: Array[AnyRef], end: Int): C + + protected def start_+(idx: Int): Int + + @inline protected final def requireBounds(idx: Int, until: Int = length): Unit = + if (idx < 0 || idx >= until) throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${until-1})") + + /** + * This is a more general version of copyToArray - this also accepts a srcStart unlike copyToArray + * This copies maxItems elements from this collections srcStart to dest's destStart + * If we reach the end of either collections before we could copy maxItems, we simply stop copying + * + * @param dest + * @param srcStart + * @param destStart + * @param maxItems + */ + def copySliceToArray(srcStart: Int, dest: Array[_], destStart: Int, maxItems: Int): dest.type = { + requireBounds(destStart, dest.length+1) + val toCopy = Math.min(maxItems, Math.min(length - srcStart, dest.length - destStart)) + if (toCopy > 0) { + requireBounds(srcStart) + val startIdx = start_+(srcStart) + val block1 = Math.min(toCopy, array.length - startIdx) + Array.copy(src = array, srcPos = startIdx, dest = dest, destPos = destStart, length = block1) + val block2 = toCopy - block1 + if (block2 > 0) Array.copy(src = array, srcPos = 0, dest = dest, destPos = destStart + block1, length = block2) + } + dest + } + + override def reverse: C = { + val n = length + val arr = ArrayDeque.alloc(n) + var i = 0 + while(i < n) { + arr(i) = this(n - i - 1).asInstanceOf[AnyRef] + i += 1 + } + ofArray(arr, n) + } + + override def slice(from: Int, until: Int): C = { + val n = length + val left = Math.max(0, Math.min(n, from)) + val right = Math.max(0, Math.min(n, until)) + val len = right - left + if (len <= 0) { + empty + } else if (len >= n) { + klone() + } else { + val array2 = copySliceToArray(srcStart = left, dest = ArrayDeque.alloc(len), destStart = 0, maxItems = len) + ofArray(array2, len) + } + } + + override def sliding(window: Int, step: Int): Iterator[C] = { + require(window > 0 && step > 0, s"window=$window and step=$step, but both must be positive") + length match { + case 0 => Iterator.empty + case n if n <= window => Iterator.single(slice(0, length)) + case n => + val lag = if (window > step) window - step else 0 + Iterator.range(start = 0, end = n - lag, step = step).map(i => slice(i, i + window)) + } + } + + override def grouped(n: Int): Iterator[C] = sliding(n, n) +} From e33fc7d24c5afdc20108fad41318efe19ce401d7 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 15:33:48 +0100 Subject: [PATCH 14/89] Make ArrayDeque capture checked --- .../collection/mutable/ArrayDeque.scala | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala b/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala index 205e1607f824..8c6b059cd8a6 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala @@ -18,6 +18,7 @@ import scala.annotation.nowarn import scala.collection.Stepper.EfficientSplit import scala.collection.generic.DefaultSerializable import scala.reflect.ClassTag +import language.experimental.captureChecking /** An implementation of a double-ended queue that internally uses a resizable circular buffer. * @@ -36,7 +37,7 @@ import scala.reflect.ClassTag * @define mayNotTerminateInf * @define willNotTerminateInf */ -class ArrayDeque[A] protected ( +class ArrayDeque[sealed A] protected ( protected var array: Array[AnyRef], private[ArrayDeque] var start: Int, private[ArrayDeque] var end: Int @@ -99,7 +100,7 @@ class ArrayDeque[A] protected ( this } - override def prependAll(elems: IterableOnce[A]): this.type = { + override def prependAll(elems: IterableOnce[A]^): this.type = { val it = elems.iterator if (it.nonEmpty) { val n = length @@ -130,7 +131,7 @@ class ArrayDeque[A] protected ( this } - override def addAll(elems: IterableOnce[A]): this.type = { + override def addAll(elems: IterableOnce[A]^): this.type = { elems.knownSize match { case srcLength if srcLength > 0 => ensureSize(srcLength + length) @@ -176,7 +177,7 @@ class ArrayDeque[A] protected ( } } - def insertAll(idx: Int, elems: IterableOnce[A]): Unit = { + def insertAll(idx: Int, elems: IterableOnce[A]^): Unit = { requireBounds(idx, length+1) val n = length if (idx == 0) { @@ -462,7 +463,7 @@ class ArrayDeque[A] protected ( protected def ofArray(array: Array[AnyRef], end: Int): ArrayDeque[A] = new ArrayDeque[A](array, start = 0, end) - override def copyToArray[B >: A](dest: Array[B], destStart: Int, len: Int): Int = { + override def copyToArray[sealed B >: A](dest: Array[B], destStart: Int, len: Int): Int = { val copied = IterableOnce.elemsToCopyToArray(length, dest.length, destStart, len) if (copied > 0) { copySliceToArray(srcStart = 0, dest = dest, destStart = destStart, maxItems = len) @@ -470,7 +471,7 @@ class ArrayDeque[A] protected ( copied } - override def toArray[B >: A: ClassTag]: Array[B] = + override def toArray[sealed B >: A: ClassTag]: Array[B] = copySliceToArray(srcStart = 0, dest = new Array[B](length), destStart = 0, maxItems = length) /** @@ -525,7 +526,7 @@ class ArrayDeque[A] protected ( @SerialVersionUID(3L) object ArrayDeque extends StrictOptimizedSeqFactory[ArrayDeque] { - def from[B](coll: collection.IterableOnce[B]): ArrayDeque[B] = { + def from[sealed B](coll: collection.IterableOnce[B]): ArrayDeque[B] = { val s = coll.knownSize if (s >= 0) { val array = alloc(s) @@ -535,14 +536,14 @@ object ArrayDeque extends StrictOptimizedSeqFactory[ArrayDeque] { } else new ArrayDeque[B]() ++= coll } - def newBuilder[A]: Builder[A, ArrayDeque[A]] = + def newBuilder[sealed A]: Builder[A, ArrayDeque[A]] = new GrowableBuilder[A, ArrayDeque[A]](empty) { override def sizeHint(size: Int): Unit = { elems.ensureSize(size) } } - def empty[A]: ArrayDeque[A] = new ArrayDeque[A]() + def empty[sealed A]: ArrayDeque[A] = new ArrayDeque[A]() final val DefaultInitialSize = 16 From 37b41b663398899bfc4cf0dacb5fc58b7457addc Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 15:34:45 +0100 Subject: [PATCH 15/89] Add Stepper.scala and ArraySeq.scala in unchanged form to stdlib --- .../stdlib/collection/Stepper.scala | 368 ++++++++++++++++++ .../stdlib/collection/mutable/ArraySeq.scala | 347 +++++++++++++++++ 2 files changed, 715 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/Stepper.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/ArraySeq.scala diff --git a/tests/pos-special/stdlib/collection/Stepper.scala b/tests/pos-special/stdlib/collection/Stepper.scala new file mode 100644 index 000000000000..0eeb8a44cb72 --- /dev/null +++ b/tests/pos-special/stdlib/collection/Stepper.scala @@ -0,0 +1,368 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import java.util.function.{Consumer, DoubleConsumer, IntConsumer, LongConsumer} +import java.util.{PrimitiveIterator, Spliterator, Iterator => JIterator} +import java.{lang => jl} + +import scala.collection.Stepper.EfficientSplit + +/** Steppers exist to enable creating Java streams over Scala collections, see + * [[scala.jdk.StreamConverters]]. Besides that use case, they allow iterating over collections + * holding unboxed primitives (e.g., `Array[Int]`) without boxing the elements. + * + * Steppers have an iterator-like interface with methods `hasStep` and `nextStep()`. The difference + * to iterators - and the reason `Stepper` is not a subtype of `Iterator` - is that there are + * hand-specialized variants of `Stepper` for `Int`, `Long` and `Double` ([[IntStepper]], etc.). + * These enable iterating over collections holding unboxed primitives (e.g., Arrays, + * [[scala.jdk.Accumulator]]s) without boxing the elements. + * + * The selection of primitive types (`Int`, `Long` and `Double`) matches the hand-specialized + * variants of Java Streams ([[java.util.stream.Stream]], [[java.util.stream.IntStream]], etc.) + * and the corresponding Java Spliterators ([[java.util.Spliterator]], [[java.util.Spliterator.OfInt]], etc.). + * + * Steppers can be converted to Scala Iterators, Java Iterators and Java Spliterators. Primitive + * Steppers are converted to the corresponding primitive Java Iterators and Spliterators. + * + * @tparam A the element type of the Stepper + */ +trait Stepper[@specialized(Double, Int, Long) +A] { + /** Check if there's an element available. */ + def hasStep: Boolean + + /** Return the next element and advance the stepper */ + def nextStep(): A + + /** Split this stepper, if applicable. The elements of the current Stepper are split up between + * the resulting Stepper and the current stepper. + * + * May return `null`, in which case the current Stepper yields the same elements as before. + * + * See method `trySplit` in [[java.util.Spliterator]]. + */ + def trySplit(): Stepper[A] + + /** Returns an estimate of the number of elements of this Stepper, or [[Long.MaxValue]]. See + * method `estimateSize` in [[java.util.Spliterator]]. + */ + def estimateSize: Long + + /** Returns a set of characteristics of this Stepper and its elements. See method + * `characteristics` in [[java.util.Spliterator]]. + */ + def characteristics: Int + + /** Returns a [[java.util.Spliterator]] corresponding to this Stepper. + * + * Note that the return type is `Spliterator[_]` instead of `Spliterator[A]` to allow returning + * a [[java.util.Spliterator.OfInt]] (which is a `Spliterator[Integer]`) in the subclass [[IntStepper]] + * (which is a `Stepper[Int]`). + */ + def spliterator[B >: A]: Spliterator[_] + + /** Returns a Java [[java.util.Iterator]] corresponding to this Stepper. + * + * Note that the return type is `Iterator[_]` instead of `Iterator[A]` to allow returning + * a [[java.util.PrimitiveIterator.OfInt]] (which is a `Iterator[Integer]`) in the subclass + * [[IntStepper]] (which is a `Stepper[Int]`). + */ + def javaIterator[B >: A]: JIterator[_] + + /** Returns an [[Iterator]] corresponding to this Stepper. Note that Iterators corresponding to + * primitive Steppers box the elements. + */ + def iterator: Iterator[A] = new AbstractIterator[A] { + def hasNext: Boolean = hasStep + def next(): A = nextStep() + } +} + +object Stepper { + /** A marker trait that indicates that a `Stepper` can call `trySplit` with at worst O(log N) time + * and space complexity, and that the division is likely to be reasonably even. Steppers marked + * with `EfficientSplit` can be converted to parallel streams with the `asJavaParStream` method + * defined in [[scala.jdk.StreamConverters]]. + */ + trait EfficientSplit + + private[collection] final def throwNSEE(): Nothing = throw new NoSuchElementException("Empty Stepper") + + /* These adapter classes can wrap an AnyStepper of a numeric type into a possibly widened primitive Stepper type. + * This provides a basis for more efficient stream processing on unboxed values provided that the original source + * of the data is boxed. In other cases native implementations of the primitive stepper types should be provided + * (see for example IntArrayStepper and WidenedByteArrayStepper). */ + + private[collection] class UnboxingDoubleStepper(st: AnyStepper[Double]) extends DoubleStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Double = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): DoubleStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingDoubleStepper(s) + } + } + + private[collection] class UnboxingIntStepper(st: AnyStepper[Int]) extends IntStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Int = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): IntStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingIntStepper(s) + } + } + + private[collection] class UnboxingLongStepper(st: AnyStepper[Long]) extends LongStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Long = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): LongStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingLongStepper(s) + } + } + + private[collection] class UnboxingByteStepper(st: AnyStepper[Byte]) extends IntStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Int = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): IntStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingByteStepper(s) + } + } + + private[collection] class UnboxingCharStepper(st: AnyStepper[Char]) extends IntStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Int = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): IntStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingCharStepper(s) + } + } + + private[collection] class UnboxingShortStepper(st: AnyStepper[Short]) extends IntStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Int = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): IntStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingShortStepper(s) + } + } + + private[collection] class UnboxingFloatStepper(st: AnyStepper[Float]) extends DoubleStepper { + def hasStep: Boolean = st.hasStep + def nextStep(): Double = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): DoubleStepper = { + val s = st.trySplit() + if (s == null) null else new UnboxingFloatStepper(s) + } + } +} + +/** A Stepper for arbitrary element types. See [[Stepper]]. */ +trait AnyStepper[+A] extends Stepper[A] { + def trySplit(): AnyStepper[A] + + def spliterator[B >: A]: Spliterator[B] = new AnyStepper.AnyStepperSpliterator(this) + + def javaIterator[B >: A]: JIterator[B] = new JIterator[B] { + def hasNext: Boolean = hasStep + def next(): B = nextStep() + } +} + +object AnyStepper { + class AnyStepperSpliterator[A](s: AnyStepper[A]) extends Spliterator[A] { + def tryAdvance(c: Consumer[_ >: A]): Boolean = + if (s.hasStep) { c.accept(s.nextStep()); true } else false + def trySplit(): Spliterator[A] = { + val sp = s.trySplit() + if (sp == null) null else sp.spliterator + } + def estimateSize(): Long = s.estimateSize + def characteristics(): Int = s.characteristics + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: Consumer[_ >: A]): Unit = + while (s.hasStep) { c.accept(s.nextStep()) } + } + + def ofSeqDoubleStepper(st: DoubleStepper): AnyStepper[Double] = new BoxedDoubleStepper(st) + def ofParDoubleStepper(st: DoubleStepper with EfficientSplit): AnyStepper[Double] with EfficientSplit = new BoxedDoubleStepper(st) with EfficientSplit + + def ofSeqIntStepper(st: IntStepper): AnyStepper[Int] = new BoxedIntStepper(st) + def ofParIntStepper(st: IntStepper with EfficientSplit): AnyStepper[Int] with EfficientSplit = new BoxedIntStepper(st) with EfficientSplit + + def ofSeqLongStepper(st: LongStepper): AnyStepper[Long] = new BoxedLongStepper(st) + def ofParLongStepper(st: LongStepper with EfficientSplit): AnyStepper[Long] with EfficientSplit = new BoxedLongStepper(st) with EfficientSplit + + private[collection] class BoxedDoubleStepper(st: DoubleStepper) extends AnyStepper[Double] { + def hasStep: Boolean = st.hasStep + def nextStep(): Double = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): AnyStepper[Double] = { + val s = st.trySplit() + if (s == null) null else new BoxedDoubleStepper(s) + } + } + + private[collection] class BoxedIntStepper(st: IntStepper) extends AnyStepper[Int] { + def hasStep: Boolean = st.hasStep + def nextStep(): Int = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): AnyStepper[Int] = { + val s = st.trySplit() + if (s == null) null else new BoxedIntStepper(s) + } + } + + private[collection] class BoxedLongStepper(st: LongStepper) extends AnyStepper[Long] { + def hasStep: Boolean = st.hasStep + def nextStep(): Long = st.nextStep() + def estimateSize: Long = st.estimateSize + def characteristics: Int = st.characteristics + def trySplit(): AnyStepper[Long] = { + val s = st.trySplit() + if (s == null) null else new BoxedLongStepper(s) + } + } +} + +/** A Stepper for Ints. See [[Stepper]]. */ +trait IntStepper extends Stepper[Int] { + def trySplit(): IntStepper + + def spliterator[B >: Int]: Spliterator.OfInt = new IntStepper.IntStepperSpliterator(this) + + def javaIterator[B >: Int]: PrimitiveIterator.OfInt = new PrimitiveIterator.OfInt { + def hasNext: Boolean = hasStep + def nextInt(): Int = nextStep() + } +} +object IntStepper { + class IntStepperSpliterator(s: IntStepper) extends Spliterator.OfInt { + def tryAdvance(c: IntConsumer): Boolean = + if (s.hasStep) { c.accept(s.nextStep()); true } else false + // Override for efficiency: don't wrap the function and call the `tryAdvance` overload + override def tryAdvance(c: Consumer[_ >: jl.Integer]): Boolean = (c: AnyRef) match { + case ic: IntConsumer => tryAdvance(ic) + case _ => if (s.hasStep) { c.accept(jl.Integer.valueOf(s.nextStep())); true } else false + } + // override required for dotty#6152 + override def trySplit(): Spliterator.OfInt = { + val sp = s.trySplit() + if (sp == null) null else sp.spliterator + } + def estimateSize(): Long = s.estimateSize + def characteristics(): Int = s.characteristics + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: IntConsumer): Unit = + while (s.hasStep) { c.accept(s.nextStep()) } + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: Consumer[_ >: jl.Integer]): Unit = (c: AnyRef) match { + case ic: IntConsumer => forEachRemaining(ic) + case _ => while (s.hasStep) { c.accept(jl.Integer.valueOf(s.nextStep())) } + } + } +} + +/** A Stepper for Doubles. See [[Stepper]]. */ +trait DoubleStepper extends Stepper[Double] { + def trySplit(): DoubleStepper + + def spliterator[B >: Double]: Spliterator.OfDouble = new DoubleStepper.DoubleStepperSpliterator(this) + + def javaIterator[B >: Double]: PrimitiveIterator.OfDouble = new PrimitiveIterator.OfDouble { + def hasNext: Boolean = hasStep + def nextDouble(): Double = nextStep() + } +} + +object DoubleStepper { + class DoubleStepperSpliterator(s: DoubleStepper) extends Spliterator.OfDouble { + def tryAdvance(c: DoubleConsumer): Boolean = + if (s.hasStep) { c.accept(s.nextStep()); true } else false + // Override for efficiency: don't wrap the function and call the `tryAdvance` overload + override def tryAdvance(c: Consumer[_ >: jl.Double]): Boolean = (c: AnyRef) match { + case ic: DoubleConsumer => tryAdvance(ic) + case _ => if (s.hasStep) { c.accept(java.lang.Double.valueOf(s.nextStep())); true } else false + } + // override required for dotty#6152 + override def trySplit(): Spliterator.OfDouble = { + val sp = s.trySplit() + if (sp == null) null else sp.spliterator + } + def estimateSize(): Long = s.estimateSize + def characteristics(): Int = s.characteristics + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: DoubleConsumer): Unit = + while (s.hasStep) { c.accept(s.nextStep()) } + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: Consumer[_ >: jl.Double]): Unit = (c: AnyRef) match { + case ic: DoubleConsumer => forEachRemaining(ic) + case _ => while (s.hasStep) { c.accept(jl.Double.valueOf(s.nextStep())) } + } + } +} + +/** A Stepper for Longs. See [[Stepper]]. */ +trait LongStepper extends Stepper[Long] { + def trySplit(): LongStepper + + def spliterator[B >: Long]: Spliterator.OfLong = new LongStepper.LongStepperSpliterator(this) + + def javaIterator[B >: Long]: PrimitiveIterator.OfLong = new PrimitiveIterator.OfLong { + def hasNext: Boolean = hasStep + def nextLong(): Long = nextStep() + } +} + +object LongStepper { + class LongStepperSpliterator(s: LongStepper) extends Spliterator.OfLong { + def tryAdvance(c: LongConsumer): Boolean = + if (s.hasStep) { c.accept(s.nextStep()); true } else false + // Override for efficiency: don't wrap the function and call the `tryAdvance` overload + override def tryAdvance(c: Consumer[_ >: jl.Long]): Boolean = (c: AnyRef) match { + case ic: LongConsumer => tryAdvance(ic) + case _ => if (s.hasStep) { c.accept(java.lang.Long.valueOf(s.nextStep())); true } else false + } + // override required for dotty#6152 + override def trySplit(): Spliterator.OfLong = { + val sp = s.trySplit() + if (sp == null) null else sp.spliterator + } + def estimateSize(): Long = s.estimateSize + def characteristics(): Int = s.characteristics + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: LongConsumer): Unit = + while (s.hasStep) { c.accept(s.nextStep()) } + // Override for efficiency: implement with hasStep / nextStep instead of tryAdvance + override def forEachRemaining(c: Consumer[_ >: jl.Long]): Unit = (c: AnyRef) match { + case ic: LongConsumer => forEachRemaining(ic) + case _ => while (s.hasStep) { c.accept(jl.Long.valueOf(s.nextStep())) } + } + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala new file mode 100644 index 000000000000..74ab6b2107e5 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala @@ -0,0 +1,347 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import java.util.Arrays + +import scala.collection.Stepper.EfficientSplit +import scala.collection.convert.impl._ +import scala.reflect.ClassTag +import scala.util.hashing.MurmurHash3 + +/** + * A collection representing `Array[T]`. Unlike `ArrayBuffer` it is always backed by the same + * underlying `Array`, therefore it is not growable or shrinkable. + * + * @tparam T type of the elements in this wrapped array. + * + * @define Coll `ArraySeq` + * @define coll wrapped array + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@SerialVersionUID(3L) +sealed abstract class ArraySeq[T] + extends AbstractSeq[T] + with IndexedSeq[T] + with IndexedSeqOps[T, ArraySeq, ArraySeq[T]] + with StrictOptimizedSeqOps[T, ArraySeq, ArraySeq[T]] + with Serializable { + + override def iterableFactory: scala.collection.SeqFactory[ArraySeq] = ArraySeq.untagged + + override protected def fromSpecific(coll: scala.collection.IterableOnce[T]): ArraySeq[T] = { + val b = ArrayBuilder.make(elemTag).asInstanceOf[ArrayBuilder[T]] + val s = coll.knownSize + if(s > 0) b.sizeHint(s) + b ++= coll + ArraySeq.make(b.result()) + } + override protected def newSpecificBuilder: Builder[T, ArraySeq[T]] = ArraySeq.newBuilder(elemTag).asInstanceOf[Builder[T, ArraySeq[T]]] + override def empty: ArraySeq[T] = ArraySeq.empty(elemTag.asInstanceOf[ClassTag[T]]) + + /** The tag of the element type. This does not have to be equal to the element type of this ArraySeq. A primitive + * ArraySeq can be backed by an array of boxed values and a reference ArraySeq can be backed by an array of a supertype + * or subtype of the element type. */ + def elemTag: ClassTag[_] + + /** Update element at given index */ + def update(@deprecatedName("idx", "2.13.0") index: Int, elem: T): Unit + + /** The underlying array. Its element type does not have to be equal to the element type of this ArraySeq. A primitive + * ArraySeq can be backed by an array of boxed values and a reference ArraySeq can be backed by an array of a supertype + * or subtype of the element type. */ + def array: Array[_] + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[T, S]): S with EfficientSplit + + override protected[this] def className = "ArraySeq" + + /** Clones this object, including the underlying Array. */ + override def clone(): ArraySeq[T] = ArraySeq.make(array.clone()).asInstanceOf[ArraySeq[T]] + + override def copyToArray[B >: T](xs: Array[B], start: Int, len: Int): Int = { + val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) + if(copied > 0) { + Array.copy(array, 0, xs, start, copied) + } + copied + } + + override def equals(other: Any): Boolean = other match { + case that: ArraySeq[_] if this.array.length != that.array.length => + false + case _ => + super.equals(other) + } + + override def sorted[B >: T](implicit ord: Ordering[B]): ArraySeq[T] = + ArraySeq.make(array.sorted(ord.asInstanceOf[Ordering[Any]])).asInstanceOf[ArraySeq[T]] + + override def sortInPlace[B >: T]()(implicit ord: Ordering[B]): this.type = { + if (length > 1) scala.util.Sorting.stableSort(array.asInstanceOf[Array[B]]) + this + } +} + +/** A companion object used to create instances of `ArraySeq`. + */ +@SerialVersionUID(3L) +object ArraySeq extends StrictOptimizedClassTagSeqFactory[ArraySeq] { self => + val untagged: SeqFactory[ArraySeq] = new ClassTagSeqFactory.AnySeqDelegate(self) + + // This is reused for all calls to empty. + private[this] val EmptyArraySeq = new ofRef[AnyRef](new Array[AnyRef](0)) + def empty[T : ClassTag]: ArraySeq[T] = EmptyArraySeq.asInstanceOf[ArraySeq[T]] + + def from[A : ClassTag](it: scala.collection.IterableOnce[A]): ArraySeq[A] = make(Array.from[A](it)) + + def newBuilder[A : ClassTag]: Builder[A, ArraySeq[A]] = ArrayBuilder.make[A].mapResult(make) + + /** + * Wrap an existing `Array` into a `ArraySeq` of the proper primitive specialization type + * without copying. + * + * Note that an array containing boxed primitives can be converted to a `ArraySeq` without + * copying. For example, `val a: Array[Any] = Array(1)` is an array of `Object` at runtime, + * containing `Integer`s. An `ArraySeq[Int]` can be obtained with a cast: + * `ArraySeq.make(a).asInstanceOf[ArraySeq[Int]]`. The values are still + * boxed, the resulting instance is an [[ArraySeq.ofRef]]. Writing + * `ArraySeq.make(a.asInstanceOf[Array[Int]])` does not work, it throws a `ClassCastException` + * at runtime. + */ + def make[T](x: Array[T]): ArraySeq[T] = ((x.asInstanceOf[Array[_]]: @unchecked) match { + case null => null + case x: Array[AnyRef] => new ofRef[AnyRef](x) + case x: Array[Int] => new ofInt(x) + case x: Array[Double] => new ofDouble(x) + case x: Array[Long] => new ofLong(x) + case x: Array[Float] => new ofFloat(x) + case x: Array[Char] => new ofChar(x) + case x: Array[Byte] => new ofByte(x) + case x: Array[Short] => new ofShort(x) + case x: Array[Boolean] => new ofBoolean(x) + case x: Array[Unit] => new ofUnit(x) + }).asInstanceOf[ArraySeq[T]] + + @SerialVersionUID(3L) + final class ofRef[T <: AnyRef](val array: Array[T]) extends ArraySeq[T] { + def elemTag = ClassTag[T](array.getClass.getComponentType) + def length: Int = array.length + def apply(index: Int): T = array(index) + def update(index: Int, elem: T): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofRef[_] => + Array.equals( + this.array.asInstanceOf[Array[AnyRef]], + that.array.asInstanceOf[Array[AnyRef]]) + case _ => super.equals(that) + } + override def iterator: Iterator[T] = new ArrayOps.ArrayIterator[T](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[T, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + new ObjectArrayStepper(array, 0, array.length) + else shape.parUnbox(new ObjectArrayStepper(array, 0, array.length).asInstanceOf[AnyStepper[T] with EfficientSplit]) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofByte(val array: Array[Byte]) extends ArraySeq[Byte] { + def elemTag = ClassTag.Byte + def length: Int = array.length + def apply(index: Int): Byte = array(index) + def update(index: Int, elem: Byte): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofByte => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Byte] = new ArrayOps.ArrayIterator[Byte](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Byte, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new WidenedByteArrayStepper(array, 0, array.length)) + else new WidenedByteArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofShort(val array: Array[Short]) extends ArraySeq[Short] { + def elemTag = ClassTag.Short + def length: Int = array.length + def apply(index: Int): Short = array(index) + def update(index: Int, elem: Short): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofShort => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Short] = new ArrayOps.ArrayIterator[Short](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Short, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new WidenedShortArrayStepper(array, 0, array.length)) + else new WidenedShortArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofChar(val array: Array[Char]) extends ArraySeq[Char] { + def elemTag = ClassTag.Char + def length: Int = array.length + def apply(index: Int): Char = array(index) + def update(index: Int, elem: Char): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofChar => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Char] = new ArrayOps.ArrayIterator[Char](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Char, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new WidenedCharArrayStepper(array, 0, array.length)) + else new WidenedCharArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + + override def addString(sb: StringBuilder, start: String, sep: String, end: String): sb.type = { + val jsb = sb.underlying + if (start.length != 0) jsb.append(start) + val len = array.length + if (len != 0) { + if (sep.isEmpty) jsb.append(array) + else { + jsb.ensureCapacity(jsb.length + len + end.length + (len - 1) * sep.length) + jsb.append(array(0)) + var i = 1 + while (i < len) { + jsb.append(sep) + jsb.append(array(i)) + i += 1 + } + } + } + if (end.length != 0) jsb.append(end) + sb + } + } + + @SerialVersionUID(3L) + final class ofInt(val array: Array[Int]) extends ArraySeq[Int] { + def elemTag = ClassTag.Int + def length: Int = array.length + def apply(index: Int): Int = array(index) + def update(index: Int, elem: Int): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofInt => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Int] = new ArrayOps.ArrayIterator[Int](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Int, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new IntArrayStepper(array, 0, array.length)) + else new IntArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofLong(val array: Array[Long]) extends ArraySeq[Long] { + def elemTag = ClassTag.Long + def length: Int = array.length + def apply(index: Int): Long = array(index) + def update(index: Int, elem: Long): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofLong => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Long] = new ArrayOps.ArrayIterator[Long](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Long, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParLongStepper(new LongArrayStepper(array, 0, array.length)) + else new LongArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofFloat(val array: Array[Float]) extends ArraySeq[Float] { + def elemTag = ClassTag.Float + def length: Int = array.length + def apply(index: Int): Float = array(index) + def update(index: Int, elem: Float): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofFloat => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Float] = new ArrayOps.ArrayIterator[Float](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Float, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParDoubleStepper(new WidenedFloatArrayStepper(array, 0, array.length)) + else new WidenedFloatArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofDouble(val array: Array[Double]) extends ArraySeq[Double] { + def elemTag = ClassTag.Double + def length: Int = array.length + def apply(index: Int): Double = array(index) + def update(index: Int, elem: Double): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofDouble => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Double] = new ArrayOps.ArrayIterator[Double](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Double, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParDoubleStepper(new DoubleArrayStepper(array, 0, array.length)) + else new DoubleArrayStepper(array, 0, array.length) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofBoolean(val array: Array[Boolean]) extends ArraySeq[Boolean] { + def elemTag = ClassTag.Boolean + def length: Int = array.length + def apply(index: Int): Boolean = array(index) + def update(index: Int, elem: Boolean): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofBoolean => Arrays.equals(array, that.array) + case _ => super.equals(that) + } + override def iterator: Iterator[Boolean] = new ArrayOps.ArrayIterator[Boolean](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Boolean, S]): S with EfficientSplit = + new BoxedBooleanArrayStepper(array, 0, array.length).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofUnit(val array: Array[Unit]) extends ArraySeq[Unit] { + def elemTag = ClassTag.Unit + def length: Int = array.length + def apply(index: Int): Unit = array(index) + def update(index: Int, elem: Unit): Unit = { array(index) = elem } + override def hashCode = MurmurHash3.arraySeqHash(array) + override def equals(that: Any) = that match { + case that: ofUnit => array.length == that.array.length + case _ => super.equals(that) + } + override def iterator: Iterator[Unit] = new ArrayOps.ArrayIterator[Unit](array) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Unit, S]): S with EfficientSplit = + new ObjectArrayStepper[AnyRef](array.asInstanceOf[Array[AnyRef]], 0, array.length).asInstanceOf[S with EfficientSplit] + } +} From ec70a238d84027ba907b777d002ef3cc763fc8e2 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 16:07:09 +0100 Subject: [PATCH 16/89] Make Stepper capture checked --- .../stdlib/collection/Stepper.scala | 40 +++--- .../stdlib/collection/StepperShape.scala | 115 ++++++++++++++++++ 2 files changed, 140 insertions(+), 15 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/StepperShape.scala diff --git a/tests/pos-special/stdlib/collection/Stepper.scala b/tests/pos-special/stdlib/collection/Stepper.scala index 0eeb8a44cb72..0a0ac0075990 100644 --- a/tests/pos-special/stdlib/collection/Stepper.scala +++ b/tests/pos-special/stdlib/collection/Stepper.scala @@ -15,6 +15,7 @@ package scala.collection import java.util.function.{Consumer, DoubleConsumer, IntConsumer, LongConsumer} import java.util.{PrimitiveIterator, Spliterator, Iterator => JIterator} import java.{lang => jl} +import language.experimental.captureChecking import scala.collection.Stepper.EfficientSplit @@ -38,6 +39,8 @@ import scala.collection.Stepper.EfficientSplit * @tparam A the element type of the Stepper */ trait Stepper[@specialized(Double, Int, Long) +A] { + this: Stepper[A]^ => + /** Check if there's an element available. */ def hasStep: Boolean @@ -183,9 +186,11 @@ object Stepper { /** A Stepper for arbitrary element types. See [[Stepper]]. */ trait AnyStepper[+A] extends Stepper[A] { + this: AnyStepper[A]^ => + def trySplit(): AnyStepper[A] - def spliterator[B >: A]: Spliterator[B] = new AnyStepper.AnyStepperSpliterator(this) + def spliterator[B >: A]: Spliterator[B]^{this} = new AnyStepper.AnyStepperSpliterator(this) def javaIterator[B >: A]: JIterator[B] = new JIterator[B] { def hasNext: Boolean = hasStep @@ -194,10 +199,10 @@ trait AnyStepper[+A] extends Stepper[A] { } object AnyStepper { - class AnyStepperSpliterator[A](s: AnyStepper[A]) extends Spliterator[A] { + class AnyStepperSpliterator[A](s: AnyStepper[A]^) extends Spliterator[A] { def tryAdvance(c: Consumer[_ >: A]): Boolean = if (s.hasStep) { c.accept(s.nextStep()); true } else false - def trySplit(): Spliterator[A] = { + def trySplit(): Spliterator[A]^{this} = { val sp = s.trySplit() if (sp == null) null else sp.spliterator } @@ -253,9 +258,11 @@ object AnyStepper { /** A Stepper for Ints. See [[Stepper]]. */ trait IntStepper extends Stepper[Int] { + this: IntStepper^ => + def trySplit(): IntStepper - def spliterator[B >: Int]: Spliterator.OfInt = new IntStepper.IntStepperSpliterator(this) + def spliterator[B >: Int]: Spliterator.OfInt^{this} = new IntStepper.IntStepperSpliterator(this) def javaIterator[B >: Int]: PrimitiveIterator.OfInt = new PrimitiveIterator.OfInt { def hasNext: Boolean = hasStep @@ -263,7 +270,7 @@ trait IntStepper extends Stepper[Int] { } } object IntStepper { - class IntStepperSpliterator(s: IntStepper) extends Spliterator.OfInt { + class IntStepperSpliterator(s: IntStepper^) extends Spliterator.OfInt { def tryAdvance(c: IntConsumer): Boolean = if (s.hasStep) { c.accept(s.nextStep()); true } else false // Override for efficiency: don't wrap the function and call the `tryAdvance` overload @@ -272,7 +279,7 @@ object IntStepper { case _ => if (s.hasStep) { c.accept(jl.Integer.valueOf(s.nextStep())); true } else false } // override required for dotty#6152 - override def trySplit(): Spliterator.OfInt = { + override def trySplit(): Spliterator.OfInt^{this} = { val sp = s.trySplit() if (sp == null) null else sp.spliterator } @@ -291,18 +298,19 @@ object IntStepper { /** A Stepper for Doubles. See [[Stepper]]. */ trait DoubleStepper extends Stepper[Double] { + this: DoubleStepper^ => def trySplit(): DoubleStepper - def spliterator[B >: Double]: Spliterator.OfDouble = new DoubleStepper.DoubleStepperSpliterator(this) + def spliterator[B >: Double]: Spliterator.OfDouble^{this} = new DoubleStepper.DoubleStepperSpliterator(this) - def javaIterator[B >: Double]: PrimitiveIterator.OfDouble = new PrimitiveIterator.OfDouble { + def javaIterator[B >: Double]: PrimitiveIterator.OfDouble^{this} = new PrimitiveIterator.OfDouble { def hasNext: Boolean = hasStep def nextDouble(): Double = nextStep() } } object DoubleStepper { - class DoubleStepperSpliterator(s: DoubleStepper) extends Spliterator.OfDouble { + class DoubleStepperSpliterator(s: DoubleStepper^) extends Spliterator.OfDouble { def tryAdvance(c: DoubleConsumer): Boolean = if (s.hasStep) { c.accept(s.nextStep()); true } else false // Override for efficiency: don't wrap the function and call the `tryAdvance` overload @@ -311,7 +319,7 @@ object DoubleStepper { case _ => if (s.hasStep) { c.accept(java.lang.Double.valueOf(s.nextStep())); true } else false } // override required for dotty#6152 - override def trySplit(): Spliterator.OfDouble = { + override def trySplit(): Spliterator.OfDouble^{this} = { val sp = s.trySplit() if (sp == null) null else sp.spliterator } @@ -330,18 +338,20 @@ object DoubleStepper { /** A Stepper for Longs. See [[Stepper]]. */ trait LongStepper extends Stepper[Long] { - def trySplit(): LongStepper + this: LongStepper^ => + + def trySplit(): LongStepper^{this} - def spliterator[B >: Long]: Spliterator.OfLong = new LongStepper.LongStepperSpliterator(this) + def spliterator[B >: Long]: Spliterator.OfLong^{this} = new LongStepper.LongStepperSpliterator(this) - def javaIterator[B >: Long]: PrimitiveIterator.OfLong = new PrimitiveIterator.OfLong { + def javaIterator[B >: Long]: PrimitiveIterator.OfLong^{this} = new PrimitiveIterator.OfLong { def hasNext: Boolean = hasStep def nextLong(): Long = nextStep() } } object LongStepper { - class LongStepperSpliterator(s: LongStepper) extends Spliterator.OfLong { + class LongStepperSpliterator(s: LongStepper^) extends Spliterator.OfLong { def tryAdvance(c: LongConsumer): Boolean = if (s.hasStep) { c.accept(s.nextStep()); true } else false // Override for efficiency: don't wrap the function and call the `tryAdvance` overload @@ -350,7 +360,7 @@ object LongStepper { case _ => if (s.hasStep) { c.accept(java.lang.Long.valueOf(s.nextStep())); true } else false } // override required for dotty#6152 - override def trySplit(): Spliterator.OfLong = { + override def trySplit(): Spliterator.OfLong^{this} = { val sp = s.trySplit() if (sp == null) null else sp.spliterator } diff --git a/tests/pos-special/stdlib/collection/StepperShape.scala b/tests/pos-special/stdlib/collection/StepperShape.scala new file mode 100644 index 000000000000..c6b520400d89 --- /dev/null +++ b/tests/pos-special/stdlib/collection/StepperShape.scala @@ -0,0 +1,115 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import java.{lang => jl} + +import language.experimental.captureChecking +import scala.collection.Stepper.EfficientSplit + +/** An implicit StepperShape instance is used in the [[IterableOnce.stepper]] to return a possibly + * specialized Stepper `S` according to the element type `T`. + */ +sealed trait StepperShape[-T, S <: Stepper[_]^] extends Pure { + /** Return the Int constant (as defined in the `StepperShape` companion object) for this `StepperShape`. */ + def shape: StepperShape.Shape + + /** Create an unboxing primitive sequential Stepper from a boxed `AnyStepper`. + * This is an identity operation for reference shapes. */ + def seqUnbox(st: AnyStepper[T]): S + + /** Create an unboxing primitive parallel (i.e. `with EfficientSplit`) Stepper from a boxed `AnyStepper`. + * This is an identity operation for reference shapes. */ + def parUnbox(st: AnyStepper[T] with EfficientSplit): S with EfficientSplit +} + +object StepperShape extends StepperShapeLowPriority1 { + class Shape private[StepperShape] (private val s: Int) extends AnyVal + + // reference + val ReferenceShape = new Shape(0) + + // primitive + val IntShape = new Shape(1) + val LongShape = new Shape(2) + val DoubleShape = new Shape(3) + + // widening + val ByteShape = new Shape(4) + val ShortShape = new Shape(5) + val CharShape = new Shape(6) + val FloatShape = new Shape(7) + + implicit val intStepperShape: StepperShape[Int, IntStepper] = new StepperShape[Int, IntStepper] { + def shape = IntShape + def seqUnbox(st: AnyStepper[Int]): IntStepper = new Stepper.UnboxingIntStepper(st) + def parUnbox(st: AnyStepper[Int] with EfficientSplit): IntStepper with EfficientSplit = new Stepper.UnboxingIntStepper(st) with EfficientSplit + } + implicit val jIntegerStepperShape: StepperShape[jl.Integer, IntStepper] = intStepperShape.asInstanceOf[StepperShape[jl.Integer, IntStepper]] + + implicit val longStepperShape: StepperShape[Long, LongStepper] = new StepperShape[Long, LongStepper] { + def shape = LongShape + def seqUnbox(st: AnyStepper[Long]): LongStepper = new Stepper.UnboxingLongStepper(st) + def parUnbox(st: AnyStepper[Long] with EfficientSplit): LongStepper with EfficientSplit = new Stepper.UnboxingLongStepper(st) with EfficientSplit + } + implicit val jLongStepperShape: StepperShape[jl.Long, LongStepper] = longStepperShape.asInstanceOf[StepperShape[jl.Long, LongStepper]] + + implicit val doubleStepperShape: StepperShape[Double, DoubleStepper] = new StepperShape[Double, DoubleStepper] { + def shape = DoubleShape + def seqUnbox(st: AnyStepper[Double]): DoubleStepper = new Stepper.UnboxingDoubleStepper(st) + def parUnbox(st: AnyStepper[Double] with EfficientSplit): DoubleStepper with EfficientSplit = new Stepper.UnboxingDoubleStepper(st) with EfficientSplit + } + implicit val jDoubleStepperShape: StepperShape[jl.Double, DoubleStepper] = doubleStepperShape.asInstanceOf[StepperShape[jl.Double, DoubleStepper]] + + implicit val byteStepperShape: StepperShape[Byte, IntStepper] = new StepperShape[Byte, IntStepper] { + def shape = ByteShape + def seqUnbox(st: AnyStepper[Byte]): IntStepper = new Stepper.UnboxingByteStepper(st) + def parUnbox(st: AnyStepper[Byte] with EfficientSplit): IntStepper with EfficientSplit = new Stepper.UnboxingByteStepper(st) with EfficientSplit + } + implicit val jByteStepperShape: StepperShape[jl.Byte, IntStepper] = byteStepperShape.asInstanceOf[StepperShape[jl.Byte, IntStepper]] + + implicit val shortStepperShape: StepperShape[Short, IntStepper] = new StepperShape[Short, IntStepper] { + def shape = ShortShape + def seqUnbox(st: AnyStepper[Short]): IntStepper = new Stepper.UnboxingShortStepper(st) + def parUnbox(st: AnyStepper[Short] with EfficientSplit): IntStepper with EfficientSplit = new Stepper.UnboxingShortStepper(st) with EfficientSplit + } + implicit val jShortStepperShape: StepperShape[jl.Short, IntStepper] = shortStepperShape.asInstanceOf[StepperShape[jl.Short, IntStepper]] + + implicit val charStepperShape: StepperShape[Char, IntStepper] = new StepperShape[Char, IntStepper] { + def shape = CharShape + def seqUnbox(st: AnyStepper[Char]): IntStepper = new Stepper.UnboxingCharStepper(st) + def parUnbox(st: AnyStepper[Char] with EfficientSplit): IntStepper with EfficientSplit = new Stepper.UnboxingCharStepper(st) with EfficientSplit + } + implicit val jCharacterStepperShape: StepperShape[jl.Character, IntStepper] = charStepperShape.asInstanceOf[StepperShape[jl.Character, IntStepper]] + + implicit val floatStepperShape: StepperShape[Float, DoubleStepper] = new StepperShape[Float, DoubleStepper] { + def shape = FloatShape + def seqUnbox(st: AnyStepper[Float]): DoubleStepper = new Stepper.UnboxingFloatStepper(st) + def parUnbox(st: AnyStepper[Float] with EfficientSplit): DoubleStepper with EfficientSplit = new Stepper.UnboxingFloatStepper(st) with EfficientSplit + } + implicit val jFloatStepperShape: StepperShape[jl.Float, DoubleStepper] = floatStepperShape.asInstanceOf[StepperShape[jl.Float, DoubleStepper]] +} + +trait StepperShapeLowPriority1 extends StepperShapeLowPriority2 { + implicit def anyStepperShape[T]: StepperShape[T, AnyStepper[T]] = anyStepperShapePrototype.asInstanceOf[StepperShape[T, AnyStepper[T]]] +} + +trait StepperShapeLowPriority2 { + implicit def baseStepperShape[T]: StepperShape[T, Stepper[T]] = anyStepperShapePrototype.asInstanceOf[StepperShape[T, Stepper[T]]] + + protected val anyStepperShapePrototype: StepperShape[AnyRef, Stepper[AnyRef]] = new StepperShape[AnyRef, Stepper[AnyRef]] { + def shape = StepperShape.ReferenceShape + def seqUnbox(st: AnyStepper[AnyRef]): Stepper[AnyRef] = st + def parUnbox(st: AnyStepper[AnyRef] with EfficientSplit): Stepper[AnyRef] with EfficientSplit = st + } +} \ No newline at end of file From 24b8a4c87a74d3e2d4e1a37b92ef97d18de48c9f Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:05:03 +0100 Subject: [PATCH 17/89] Don't generate capture set variables for self types of pure classes The tricky thing here is how to recognize that a class is pure since that is known only during capture checking and we are at Setup, the phase before. But we can approximate by treating the `Pure` trait as definitely pure. --- compiler/src/dotty/tools/dotc/cc/Setup.scala | 4 ++- .../dotty/tools/dotc/core/Definitions.scala | 2 +- tests/pos-custom-args/captures/steppers.scala | 27 +++++++++++++++++++ 3 files changed, 31 insertions(+), 2 deletions(-) create mode 100644 tests/pos-custom-args/captures/steppers.scala diff --git a/compiler/src/dotty/tools/dotc/cc/Setup.scala b/compiler/src/dotty/tools/dotc/cc/Setup.scala index 68fd79048f41..e90a8394f87d 100644 --- a/compiler/src/dotty/tools/dotc/cc/Setup.scala +++ b/compiler/src/dotty/tools/dotc/cc/Setup.scala @@ -522,7 +522,9 @@ class Setup extends PreRecheck, SymTransformer, SetupAPI: tree.symbol match case cls: ClassSymbol => val cinfo @ ClassInfo(prefix, _, ps, decls, selfInfo) = cls.classInfo - if (selfInfo eq NoType) || cls.is(ModuleClass) && !cls.isStatic then + if ((selfInfo eq NoType) || cls.is(ModuleClass) && !cls.isStatic) + && !cls.isPureClass + then // add capture set to self type of nested classes if no self type is given explicitly. val newSelfType = CapturingType(cinfo.selfType, CaptureSet.Var(cls)) val ps1 = inContext(ctx.withOwner(cls)): diff --git a/compiler/src/dotty/tools/dotc/core/Definitions.scala b/compiler/src/dotty/tools/dotc/core/Definitions.scala index 205d43cd07ca..40370973ebf0 100644 --- a/compiler/src/dotty/tools/dotc/core/Definitions.scala +++ b/compiler/src/dotty/tools/dotc/core/Definitions.scala @@ -1443,7 +1443,7 @@ class Definitions { /** Base classes that are assumed to be pure for the purposes of capture checking. * Every class inheriting from a pure baseclass is pure. */ - @tu lazy val pureBaseClasses = Set(defn.ThrowableClass) + @tu lazy val pureBaseClasses = Set(ThrowableClass, PureClass) /** Non-inheritable lasses that are assumed to be pure for the purposes of capture checking, */ diff --git a/tests/pos-custom-args/captures/steppers.scala b/tests/pos-custom-args/captures/steppers.scala new file mode 100644 index 000000000000..815ac938b492 --- /dev/null +++ b/tests/pos-custom-args/captures/steppers.scala @@ -0,0 +1,27 @@ + +trait Stepper[+A]: + this: Stepper[A]^ => + +object Stepper: + trait EfficientSplit + +sealed trait StepperShape[-T, S <: Stepper[_]^] extends Pure + +trait IterableOnce[+A] extends Any: + this: IterableOnce[A]^ => + def stepper[S <: Stepper[_]^{this}](implicit shape: StepperShape[A, S]): S = ??? + +sealed abstract class ArraySeq[sealed T] extends IterableOnce[T], Pure: + def array: Array[_] + + def sorted[B >: T](implicit ord: Ordering[B]): ArraySeq[T] = + val arr = array.asInstanceOf[Array[T]].sorted(ord.asInstanceOf[Ordering[Any]]).asInstanceOf[Array[T]] + ArraySeq.make(arr).asInstanceOf[ArraySeq[T]] + +object ArraySeq: + + def make[sealed T](x: Array[T]): ArraySeq[T] = ??? + + final class ofRef[T <: AnyRef](val array: Array[T]) extends ArraySeq[T], Pure: + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[T, S]): S & Stepper.EfficientSplit = ??? + From 6ba065ee658eeaa4286979b7baeaf0fe0de7c134 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:05:37 +0100 Subject: [PATCH 18/89] Make ArraySeq capture checked --- .../stdlib/collection/mutable/ArraySeq.scala | 23 +++++++++++-------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala index 74ab6b2107e5..9bdb28517eff 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala @@ -19,6 +19,8 @@ import scala.collection.Stepper.EfficientSplit import scala.collection.convert.impl._ import scala.reflect.ClassTag import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking +import annotation.unchecked.uncheckedCaptures /** * A collection representing `Array[T]`. Unlike `ArrayBuffer` it is always backed by the same @@ -34,7 +36,7 @@ import scala.util.hashing.MurmurHash3 * @define willNotTerminateInf */ @SerialVersionUID(3L) -sealed abstract class ArraySeq[T] +sealed abstract class ArraySeq[sealed T] extends AbstractSeq[T] with IndexedSeq[T] with IndexedSeqOps[T, ArraySeq, ArraySeq[T]] @@ -43,14 +45,15 @@ sealed abstract class ArraySeq[T] override def iterableFactory: scala.collection.SeqFactory[ArraySeq] = ArraySeq.untagged - override protected def fromSpecific(coll: scala.collection.IterableOnce[T]): ArraySeq[T] = { + override protected def fromSpecific(coll: scala.collection.IterableOnce[T]^): ArraySeq[T] = { val b = ArrayBuilder.make(elemTag).asInstanceOf[ArrayBuilder[T]] val s = coll.knownSize if(s > 0) b.sizeHint(s) b ++= coll ArraySeq.make(b.result()) } - override protected def newSpecificBuilder: Builder[T, ArraySeq[T]] = ArraySeq.newBuilder(elemTag).asInstanceOf[Builder[T, ArraySeq[T]]] + override protected def newSpecificBuilder: Builder[T, ArraySeq[T]] = + ArraySeq.newBuilder[T](elemTag.asInstanceOf[ClassTag[T]]).asInstanceOf[Builder[T, ArraySeq[T]]] override def empty: ArraySeq[T] = ArraySeq.empty(elemTag.asInstanceOf[ClassTag[T]]) /** The tag of the element type. This does not have to be equal to the element type of this ArraySeq. A primitive @@ -71,9 +74,9 @@ sealed abstract class ArraySeq[T] override protected[this] def className = "ArraySeq" /** Clones this object, including the underlying Array. */ - override def clone(): ArraySeq[T] = ArraySeq.make(array.clone()).asInstanceOf[ArraySeq[T]] + override def clone(): ArraySeq[T] = ArraySeq.make[T](array.clone().asInstanceOf[Array[T]]) - override def copyToArray[B >: T](xs: Array[B], start: Int, len: Int): Int = { + override def copyToArray[sealed B >: T](xs: Array[B], start: Int, len: Int): Int = { val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) if(copied > 0) { Array.copy(array, 0, xs, start, copied) @@ -89,10 +92,10 @@ sealed abstract class ArraySeq[T] } override def sorted[B >: T](implicit ord: Ordering[B]): ArraySeq[T] = - ArraySeq.make(array.sorted(ord.asInstanceOf[Ordering[Any]])).asInstanceOf[ArraySeq[T]] + ArraySeq.make(array.asInstanceOf[Array[T]].sorted(ord.asInstanceOf[Ordering[Any]])).asInstanceOf[ArraySeq[T]] override def sortInPlace[B >: T]()(implicit ord: Ordering[B]): this.type = { - if (length > 1) scala.util.Sorting.stableSort(array.asInstanceOf[Array[B]]) + if (length > 1) scala.util.Sorting.stableSort(array.asInstanceOf[Array[B @uncheckedCaptures]]) this } } @@ -107,9 +110,9 @@ object ArraySeq extends StrictOptimizedClassTagSeqFactory[ArraySeq] { self => private[this] val EmptyArraySeq = new ofRef[AnyRef](new Array[AnyRef](0)) def empty[T : ClassTag]: ArraySeq[T] = EmptyArraySeq.asInstanceOf[ArraySeq[T]] - def from[A : ClassTag](it: scala.collection.IterableOnce[A]): ArraySeq[A] = make(Array.from[A](it)) + def from[sealed A : ClassTag](it: scala.collection.IterableOnce[A]): ArraySeq[A] = make(Array.from[A](it)) - def newBuilder[A : ClassTag]: Builder[A, ArraySeq[A]] = ArrayBuilder.make[A].mapResult(make) + def newBuilder[sealed A : ClassTag]: Builder[A, ArraySeq[A]] = ArrayBuilder.make[A].mapResult(make) /** * Wrap an existing `Array` into a `ArraySeq` of the proper primitive specialization type @@ -123,7 +126,7 @@ object ArraySeq extends StrictOptimizedClassTagSeqFactory[ArraySeq] { self => * `ArraySeq.make(a.asInstanceOf[Array[Int]])` does not work, it throws a `ClassCastException` * at runtime. */ - def make[T](x: Array[T]): ArraySeq[T] = ((x.asInstanceOf[Array[_]]: @unchecked) match { + def make[sealed T](x: Array[T]): ArraySeq[T] = ((x.asInstanceOf[Array[_]]: @unchecked) match { case null => null case x: Array[AnyRef] => new ofRef[AnyRef](x) case x: Array[Int] => new ofInt(x) From bb650465e3c1e2833a7247fc0602dc3a4897e745 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:13:19 +0100 Subject: [PATCH 19/89] Add mutable/IndexedSeq.scala to stdlib (capture checks out of the box) --- .../collection/mutable/IndexedSeq.scala | 84 +++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/IndexedSeq.scala diff --git a/tests/pos-special/stdlib/collection/mutable/IndexedSeq.scala b/tests/pos-special/stdlib/collection/mutable/IndexedSeq.scala new file mode 100644 index 000000000000..022970b4c56f --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/IndexedSeq.scala @@ -0,0 +1,84 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable +import language.experimental.captureChecking + +trait IndexedSeq[T] extends Seq[T] + with scala.collection.IndexedSeq[T] + with IndexedSeqOps[T, IndexedSeq, IndexedSeq[T]] + with IterableFactoryDefaults[T, IndexedSeq] { + + override def iterableFactory: SeqFactory[IndexedSeq] = IndexedSeq +} + +@SerialVersionUID(3L) +object IndexedSeq extends SeqFactory.Delegate[IndexedSeq](ArrayBuffer) + +trait IndexedSeqOps[A, +CC[_], +C <: AnyRef] + extends scala.collection.IndexedSeqOps[A, CC, C] + with SeqOps[A, CC, C] { + + /** Modifies this $coll by applying a function to all elements of this $coll. + * + * @param f the function to apply to each element. + * @return this $coll modified by replacing all elements with the + * result of applying the given function `f` to each element + * of this $coll. + */ + def mapInPlace(f: A => A): this.type = { + var i = 0 + val siz = size + while (i < siz) { this(i) = f(this(i)); i += 1 } + this + } + + /** Sorts this $coll in place according to an Ordering. + * + * @see [[scala.collection.SeqOps.sorted]] + * @param ord the ordering to be used to compare elements. + * @return modified input $coll sorted according to the ordering `ord`. + */ + def sortInPlace[B >: A]()(implicit ord: Ordering[B]): this.type = { + val len = this.length + if (len > 1) { + val arr = new Array[AnyRef](len) + var i = 0 + for (x <- this) { + arr(i) = x.asInstanceOf[AnyRef] + i += 1 + } + java.util.Arrays.sort(arr, ord.asInstanceOf[Ordering[Object]]) + i = 0 + while (i < arr.length) { + update(i, arr(i).asInstanceOf[A]) + i += 1 + } + } + this + } + + /** Sorts this $coll in place according to a comparison function. + * + * @see [[scala.collection.SeqOps.sortWith]] + */ + def sortInPlaceWith(lt: (A, A) => Boolean): this.type = sortInPlace()(Ordering.fromLessThan(lt)) + + /** Sorts this $coll in place according to the Ordering which results from transforming + * an implicitly given Ordering with a transformation function. + * + * @see [[scala.collection.SeqOps.sortBy]] + */ + def sortInPlaceBy[B](f: A => B)(implicit ord: Ordering[B]): this.type = sortInPlace()(ord on f) + +} From c811e353cded4422ae644b818f1149663916c625 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:19:53 +0100 Subject: [PATCH 20/89] Add Queue.scala to stdlib --- .../stdlib/collection/Iterator.scala | 4 +- .../stdlib/collection/mutable/Queue.scala | 139 ++++++++++++++++++ 2 files changed, 141 insertions(+), 2 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/mutable/Queue.scala diff --git a/tests/pos-special/stdlib/collection/Iterator.scala b/tests/pos-special/stdlib/collection/Iterator.scala index 68ea4f76c249..172cd7c2a282 100644 --- a/tests/pos-special/stdlib/collection/Iterator.scala +++ b/tests/pos-special/stdlib/collection/Iterator.scala @@ -705,7 +705,7 @@ trait Iterator[+A] extends IterableOnce[A] with IterableOnceOps[A, Iterator, Ite */ private[this] var status = 0 private def store(a: A): Unit = { - if (lookahead == null) lookahead = new mutable.Queue[A] + if (lookahead == null) lookahead = new mutable.Queue[A @uncheckedCaptures] lookahead += a } def hasNext = { @@ -868,7 +868,7 @@ trait Iterator[+A] extends IterableOnce[A] with IterableOnceOps[A, Iterator, Ite * @note Reuse: $consumesOneAndProducesTwoIterators */ def duplicate: (Iterator[A]^{this}, Iterator[A]^{this}) = { - val gap = new scala.collection.mutable.Queue[A] + val gap = new scala.collection.mutable.Queue[A @uncheckedCaptures] var ahead: Iterator[A] = null class Partner extends AbstractIterator[A] { override def knownSize: Int = self.synchronized { diff --git a/tests/pos-special/stdlib/collection/mutable/Queue.scala b/tests/pos-special/stdlib/collection/mutable/Queue.scala new file mode 100644 index 000000000000..8c0b5cea1133 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/Queue.scala @@ -0,0 +1,139 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.annotation.nowarn +import scala.collection.generic.DefaultSerializable +import language.experimental.captureChecking + + +/** `Queue` objects implement data structures that allow to + * insert and retrieve elements in a first-in-first-out (FIFO) manner. + * + * @define Coll `mutable.Queue` + * @define coll mutable queue + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +class Queue[sealed A] protected (array: Array[AnyRef], start: Int, end: Int) + extends ArrayDeque[A](array, start, end) + with IndexedSeqOps[A, Queue, Queue[A]] + with StrictOptimizedSeqOps[A, Queue, Queue[A]] + with IterableFactoryDefaults[A, Queue] + with ArrayDequeOps[A, Queue, Queue[A]] + with Cloneable[Queue[A]] + with DefaultSerializable { + + def this(initialSize: Int = ArrayDeque.DefaultInitialSize) = + this(ArrayDeque.alloc(initialSize), start = 0, end = 0) + + override def iterableFactory: SeqFactory[Queue] = Queue + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "Queue" + + /** + * Add elements to the end of this queue + * + * @param elem + * @return this + */ + def enqueue(elem: A): this.type = this += elem + + /** Enqueue two or more elements at the end of the queue. The last element + * of the sequence will be on end of the queue. + * + * @param elems the element sequence. + * @return this + */ + def enqueue(elem1: A, elem2: A, elems: A*): this.type = enqueue(elem1).enqueue(elem2).enqueueAll(elems) + + /** Enqueues all elements in the given iterable object into the queue. The + * last element in the iterable object will be on front of the new queue. + * + * @param elems the iterable object. + * @return this + */ + def enqueueAll(elems: scala.collection.IterableOnce[A]): this.type = this ++= elems + + /** + * Removes the first element from this queue and returns it + * + * @return + * @throws NoSuchElementException when queue is empty + */ + def dequeue(): A = removeHead() + + /** Returns the first element in the queue which satisfies the + * given predicate, and removes this element from the queue. + * + * @param p the predicate used for choosing the first element + * @return the first element of the queue for which p yields true + */ + def dequeueFirst(p: A => Boolean): Option[A] = + removeFirst(p) + + /** Returns all elements in the queue which satisfy the + * given predicate, and removes those elements from the queue. + * + * @param p the predicate used for choosing elements + * @return a sequence of all elements in the queue for which + * p yields true. + */ + def dequeueAll(p: A => Boolean): scala.collection.immutable.Seq[A] = + removeAll(p) + + /** + * Returns and dequeues all elements from the queue which satisfy the given predicate + * + * @param f the predicate used for choosing elements + * @return The removed elements + */ + def dequeueWhile(f: A => Boolean): scala.collection.Seq[A] = removeHeadWhile(f) + + /** Returns the first element in the queue, or throws an error if there + * is no element contained in the queue. + * + * @return the first element. + */ + @`inline` final def front: A = head + + override protected def klone(): Queue[A] = { + val bf = newSpecificBuilder + bf ++= this + bf.result() + } + + override protected def ofArray(array: Array[AnyRef], end: Int): Queue[A] = + new Queue(array, start = 0, end) + +} + +/** + * $factoryInfo + * @define coll queue + * @define Coll `Queue` + */ +@SerialVersionUID(3L) +object Queue extends StrictOptimizedSeqFactory[Queue] { + + def from[sealed A](source: IterableOnce[A]): Queue[A] = empty ++= source + + def empty[sealed A]: Queue[A] = new Queue + + def newBuilder[sealed A]: Builder[A, Queue[A]] = new GrowableBuilder[A, Queue[A]](empty) + +} From f0a1241ede5604952f38a4136627ac29bc83b09c Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:20:43 +0100 Subject: [PATCH 21/89] Add PriorityQueue.scala to stdlib --- .../collection/mutable/PriorityQueue.scala | 402 ++++++++++++++++++ 1 file changed, 402 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala diff --git a/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala b/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala new file mode 100644 index 000000000000..5572bdca3cf6 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala @@ -0,0 +1,402 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.collection.generic.DefaultSerializationProxy +import scala.math.Ordering + +/** A heap-based priority queue. + * + * To prioritize elements of type `A` there must be an implicit + * `Ordering[A]` available at creation. Elements are retrieved + * in priority order by using [[dequeue]] or [[dequeueAll]]. + * + * If multiple elements have the same priority as determined by the ordering for this + * `PriorityQueue`, no guarantees are made regarding the order in which those elements + * are returned by `dequeue` or `dequeueAll`. In particular, that means this + * class does not guarantee first-in-first-out behavior, as may be + * incorrectly inferred from the fact that this data structure is + * called a "queue". + * + * Only the `dequeue` and `dequeueAll` methods will return elements in priority + * order (while removing elements from the heap). Standard collection methods + * such as `drop`, `iterator`, `toList` and `toString` use an arbitrary + * iteration order: they will traverse the heap or remove elements + * in whichever order seems most convenient. + * + * Therefore, printing a `PriorityQueue` will not show elements in priority order, + * though the highest-priority element will be printed first. + * To print the elements in order, it's necessary to `dequeue` them. + * To do this non-destructively, duplicate the `PriorityQueue` first; + * the `clone` method is a suitable way to obtain a disposable copy. + * + * Client keys are assumed to be immutable. Mutating keys may violate + * the invariant of the underlying heap-ordered tree. Note that [[clone]] + * does not rebuild the underlying tree. + * + * {{{ + * scala> val pq = collection.mutable.PriorityQueue(1, 2, 5, 3, 7) + * val pq: scala.collection.mutable.PriorityQueue[Int] = PriorityQueue(7, 3, 5, 1, 2) + * + * scala> pq.toList // also not in order + * val res0: List[Int] = List(7, 3, 5, 1, 2) + * + * scala> pq.clone.dequeueAll + * val res1: Seq[Int] = ArraySeq(7, 5, 3, 2, 1) + * }}} + * + * @tparam A type of the elements in this priority queue. + * @param ord implicit ordering used to compare the elements of type `A`. + * + * @define Coll PriorityQueue + * @define coll priority queue + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +sealed class PriorityQueue[A](implicit val ord: Ordering[A]) + extends AbstractIterable[A] + with Iterable[A] + with IterableOps[A, Iterable, PriorityQueue[A]] + with StrictOptimizedIterableOps[A, Iterable, PriorityQueue[A]] + with Builder[A, PriorityQueue[A]] + with Cloneable[PriorityQueue[A]] + with Growable[A] + with Serializable +{ + + private class ResizableArrayAccess[A0] extends ArrayBuffer[A0] { + override def mapInPlace(f: A0 => A0): this.type = { + var i = 1 // see "we do not use array(0)" comment below (???) + val siz = this.size + while (i < siz) { this(i) = f(this(i)); i += 1 } + this + } + + def p_size0 = size0 + def p_size0_=(s: Int) = size0 = s + def p_array = array + def p_ensureSize(n: Int) = super.ensureSize(n) + def p_ensureAdditionalSize(n: Int) = super.ensureAdditionalSize(n) + def p_swap(a: Int, b: Int): Unit = { + val h = array(a) + array(a) = array(b) + array(b) = h + } + } + + private val resarr = new ResizableArrayAccess[A] + + resarr.p_size0 += 1 // we do not use array(0) TODO: explain -- what is the first element even for? + def length: Int = resarr.length - 1 // adjust length accordingly + override def size: Int = length + override def knownSize: Int = length + override def isEmpty: Boolean = resarr.p_size0 < 2 + + // not eligible for EvidenceIterableFactoryDefaults since C != CC[A] (PriorityQueue[A] != Iterable[A]) + override protected def fromSpecific(coll: scala.collection.IterableOnce[A]): PriorityQueue[A] = PriorityQueue.from(coll) + override protected def newSpecificBuilder: Builder[A, PriorityQueue[A]] = PriorityQueue.newBuilder + override def empty: PriorityQueue[A] = PriorityQueue.empty + + def mapInPlace(f: A => A): this.type = { + resarr.mapInPlace(f) + heapify(1) + this + } + + def result() = this + + private def toA(x: AnyRef): A = x.asInstanceOf[A] + protected def fixUp(as: Array[AnyRef], m: Int): Unit = { + var k: Int = m + // use `ord` directly to avoid allocating `OrderingOps` + while (k > 1 && ord.lt(toA(as(k / 2)), toA(as(k)))) { + resarr.p_swap(k, k / 2) + k = k / 2 + } + } + + protected def fixDown(as: Array[AnyRef], m: Int, n: Int): Boolean = { + // returns true if any swaps were done (used in heapify) + var k: Int = m + while (n >= 2 * k) { + var j = 2 * k + // use `ord` directly to avoid allocating `OrderingOps` + if (j < n && ord.lt(toA(as(j)), toA(as(j + 1)))) + j += 1 + if (ord.gteq(toA(as(k)), toA(as(j)))) + return k != m + else { + val h = as(k) + as(k) = as(j) + as(j) = h + k = j + } + } + k != m + } + + /** Inserts a single element into the priority queue. + * + * @param elem the element to insert. + * @return this $coll. + */ + def addOne(elem: A): this.type = { + resarr.p_ensureAdditionalSize(1) + resarr.p_array(resarr.p_size0) = elem.asInstanceOf[AnyRef] + fixUp(resarr.p_array, resarr.p_size0) + resarr.p_size0 += 1 + this + } + + override def addAll(xs: IterableOnce[A]): this.type = { + val from = resarr.p_size0 + for (x <- xs.iterator) unsafeAdd(x) + heapify(from) + this + } + + private def unsafeAdd(elem: A): Unit = { + // like += but skips fixUp, which breaks the ordering invariant + // a series of unsafeAdds MUST be followed by heapify + resarr.p_ensureAdditionalSize(1) + resarr.p_array(resarr.p_size0) = elem.asInstanceOf[AnyRef] + resarr.p_size0 += 1 + } + + private def heapify(from: Int): Unit = { + // elements at indices 1..from-1 were already in heap order before any adds + // elements at indices from..n are newly added, their order must be fixed + val n = length + + if (from <= 2) { + // no pre-existing order to maintain, do the textbook heapify algorithm + for (i <- n/2 to 1 by -1) fixDown(resarr.p_array, i, n) + } + else if (n - from < 4) { + // for very small adds, doing the simplest fix is faster + for (i <- from to n) fixUp(resarr.p_array, i) + } + else { + var min = from/2 // tracks the minimum element in the queue + val queue = scala.collection.mutable.Queue[Int](min) + + // do fixDown on the parents of all the new elements + // except the parent of the first new element, which is in the queue + // (that parent is treated specially because it might be the root) + for (i <- n/2 until min by -1) { + if (fixDown(resarr.p_array, i, n)) { + // there was a swap, so also need to fixDown i's parent + val parent = i/2 + if (parent < min) { // make sure same parent isn't added twice + min = parent + queue += parent + } + } + } + + while (queue.nonEmpty) { + val i = queue.dequeue() + if (fixDown(resarr.p_array, i, n)) { + val parent = i/2 + if (parent < min && parent > 0) { + // the "parent > 0" is to avoid adding the parent of the root + min = parent + queue += parent + } + } + } + } + } + + /** Adds all elements provided by a `IterableOnce` object + * into the priority queue. + * + * @param xs a iterable object. + * @return a new priority queue containing elements of both `xs` and `this`. + */ + def ++(xs: IterableOnce[A]): PriorityQueue[A] = { this.clone() ++= xs } + + /** Adds all elements to the queue. + * + * @param elems the elements to add. + */ + def enqueue(elems: A*): Unit = { this ++= elems } + + /** Returns the element with the highest priority in the queue, + * and removes this element from the queue. + * + * @throws NoSuchElementException + * @return the element with the highest priority. + */ + def dequeue(): A = + if (resarr.p_size0 > 1) { + resarr.p_size0 = resarr.p_size0 - 1 + val result = resarr.p_array(1) + resarr.p_array(1) = resarr.p_array(resarr.p_size0) + resarr.p_array(resarr.p_size0) = null // erase reference from array + fixDown(resarr.p_array, 1, resarr.p_size0 - 1) + toA(result) + } else + throw new NoSuchElementException("no element to remove from heap") + + def dequeueAll[A1 >: A]: immutable.Seq[A1] = { + val b = ArrayBuilder.make[Any] + b.sizeHint(size) + while (nonEmpty) { + b += dequeue() + } + immutable.ArraySeq.unsafeWrapArray(b.result()).asInstanceOf[immutable.ArraySeq[A1]] + } + + /** Returns the element with the highest priority in the queue, + * or throws an error if there is no element contained in the queue. + * + * @return the element with the highest priority. + */ + override def head: A = if (resarr.p_size0 > 1) toA(resarr.p_array(1)) else throw new NoSuchElementException("queue is empty") + + /** Removes all elements from the queue. After this operation is completed, + * the queue will be empty. + */ + def clear(): Unit = { + resarr.clear() + resarr.p_size0 = 1 + } + + /** Returns an iterator which yields all the elements. + * + * Note: The order of elements returned is undefined. + * If you want to traverse the elements in priority queue + * order, use `clone().dequeueAll.iterator`. + * + * @return an iterator over all the elements. + */ + override def iterator: Iterator[A] = resarr.iterator.drop(1) + + /** Returns the reverse of this priority queue. The new priority queue has + * the same elements as the original, but the opposite ordering. + * + * For example, the element with the highest priority in `pq` has the lowest + * priority in `pq.reverse`, and vice versa. + * + * Ties are handled arbitrarily. Elements with equal priority may or + * may not be reversed with respect to each other. + * + * @return the reversed priority queue. + */ + def reverse: PriorityQueue[A] = { + val revq = new PriorityQueue[A]()(ord.reverse) + // copy the existing data into the new array backwards + // this won't put it exactly into the correct order, + // but will require less fixing than copying it in + // the original order + val n = resarr.p_size0 + revq.resarr.p_ensureSize(n) + revq.resarr.p_size0 = n + val from = resarr.p_array + val to = revq.resarr.p_array + for (i <- 1 until n) to(i) = from(n-i) + revq.heapify(1) + revq + } + + + /** Returns an iterator which yields all the elements in the reverse order + * than that returned by the method `iterator`. + * + * Note: The order of elements returned is undefined. + * + * @return an iterator over all elements sorted in descending order. + */ + def reverseIterator: Iterator[A] = new AbstractIterator[A] { + private[this] var i = resarr.p_size0 - 1 + def hasNext: Boolean = i >= 1 + def next(): A = { + val n = resarr.p_array(i) + i -= 1 + toA(n) + } + } + + /** Returns a regular queue containing the same elements. + * + * Note: the order of elements is undefined. + */ + def toQueue: Queue[A] = new Queue[A] ++= this.iterator + + /** Returns a textual representation of a queue as a string. + * + * @return the string representation of this queue. + */ + override def toString() = toList.mkString("PriorityQueue(", ", ", ")") + + /** Converts this $coll to a list. + * + * Note: the order of elements is undefined. + * + * @return a list containing all elements of this $coll. + */ + override def toList: immutable.List[A] = immutable.List.from(this.iterator) + + /** This method clones the priority queue. + * + * @return a priority queue with the same elements. + */ + override def clone(): PriorityQueue[A] = { + val pq = new PriorityQueue[A] + val n = resarr.p_size0 + pq.resarr.p_ensureSize(n) + java.lang.System.arraycopy(resarr.p_array, 1, pq.resarr.p_array, 1, n-1) + pq.resarr.p_size0 = n + pq + } + + override def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) + if (copied > 0) { + Array.copy(resarr.p_array, 1, xs, start, copied) + } + copied + } + + @deprecated("Use `PriorityQueue` instead", "2.13.0") + def orderedCompanion: PriorityQueue.type = PriorityQueue + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(PriorityQueue.evidenceIterableFactory[A], this) + + override protected[this] def className = "PriorityQueue" +} + + +@SerialVersionUID(3L) +object PriorityQueue extends SortedIterableFactory[PriorityQueue] { + def newBuilder[A : Ordering]: Builder[A, PriorityQueue[A]] = { + new Builder[A, PriorityQueue[A]] { + val pq = new PriorityQueue[A] + def addOne(elem: A): this.type = { pq.unsafeAdd(elem); this } + def result(): PriorityQueue[A] = { pq.heapify(1); pq } + def clear(): Unit = pq.clear() + } + } + + def empty[A : Ordering]: PriorityQueue[A] = new PriorityQueue[A] + + def from[E : Ordering](it: IterableOnce[E]): PriorityQueue[E] = { + val b = newBuilder[E] + b ++= it + b.result() + } +} From 4ac21393f1330d2925315b111eff3184f5f5a5d2 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:24:08 +0100 Subject: [PATCH 22/89] Make PriorityQueue capture checked --- .../collection/mutable/PriorityQueue.scala | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala b/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala index 5572bdca3cf6..a395fac4a44a 100644 --- a/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala +++ b/tests/pos-special/stdlib/collection/mutable/PriorityQueue.scala @@ -15,6 +15,7 @@ package mutable import scala.collection.generic.DefaultSerializationProxy import scala.math.Ordering +import language.experimental.captureChecking /** A heap-based priority queue. * @@ -66,7 +67,7 @@ import scala.math.Ordering * @define mayNotTerminateInf * @define willNotTerminateInf */ -sealed class PriorityQueue[A](implicit val ord: Ordering[A]) +sealed class PriorityQueue[sealed A](implicit val ord: Ordering[A]) extends AbstractIterable[A] with Iterable[A] with IterableOps[A, Iterable, PriorityQueue[A]] @@ -77,7 +78,7 @@ sealed class PriorityQueue[A](implicit val ord: Ordering[A]) with Serializable { - private class ResizableArrayAccess[A0] extends ArrayBuffer[A0] { + private class ResizableArrayAccess[sealed A0] extends ArrayBuffer[A0] { override def mapInPlace(f: A0 => A0): this.type = { var i = 1 // see "we do not use array(0)" comment below (???) val siz = this.size @@ -106,7 +107,7 @@ sealed class PriorityQueue[A](implicit val ord: Ordering[A]) override def isEmpty: Boolean = resarr.p_size0 < 2 // not eligible for EvidenceIterableFactoryDefaults since C != CC[A] (PriorityQueue[A] != Iterable[A]) - override protected def fromSpecific(coll: scala.collection.IterableOnce[A]): PriorityQueue[A] = PriorityQueue.from(coll) + override protected def fromSpecific(coll: scala.collection.IterableOnce[A]^): PriorityQueue[A] = PriorityQueue.from(coll) override protected def newSpecificBuilder: Builder[A, PriorityQueue[A]] = PriorityQueue.newBuilder override def empty: PriorityQueue[A] = PriorityQueue.empty @@ -161,7 +162,7 @@ sealed class PriorityQueue[A](implicit val ord: Ordering[A]) this } - override def addAll(xs: IterableOnce[A]): this.type = { + override def addAll(xs: IterableOnce[A]^): this.type = { val from = resarr.p_size0 for (x <- xs.iterator) unsafeAdd(x) heapify(from) @@ -364,7 +365,7 @@ sealed class PriorityQueue[A](implicit val ord: Ordering[A]) pq } - override def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + override def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = { val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) if (copied > 0) { Array.copy(resarr.p_array, 1, xs, start, copied) @@ -383,7 +384,7 @@ sealed class PriorityQueue[A](implicit val ord: Ordering[A]) @SerialVersionUID(3L) object PriorityQueue extends SortedIterableFactory[PriorityQueue] { - def newBuilder[A : Ordering]: Builder[A, PriorityQueue[A]] = { + def newBuilder[sealed A : Ordering]: Builder[A, PriorityQueue[A]] = { new Builder[A, PriorityQueue[A]] { val pq = new PriorityQueue[A] def addOne(elem: A): this.type = { pq.unsafeAdd(elem); this } @@ -392,9 +393,9 @@ object PriorityQueue extends SortedIterableFactory[PriorityQueue] { } } - def empty[A : Ordering]: PriorityQueue[A] = new PriorityQueue[A] + def empty[sealed A : Ordering]: PriorityQueue[A] = new PriorityQueue[A] - def from[E : Ordering](it: IterableOnce[E]): PriorityQueue[E] = { + def from[sealed E : Ordering](it: IterableOnce[E]^): PriorityQueue[E] = { val b = newBuilder[E] b ++= it b.result() From 4795ef84780e4b331ce6fbde87aba383ec70de48 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:27:16 +0100 Subject: [PATCH 23/89] Add Stack.scala and ReusableBuilder.scala to stdlib --- .../collection/mutable/ReusableBuilder.scala | 56 +++++++ .../stdlib/collection/mutable/Stack.scala | 144 ++++++++++++++++++ 2 files changed, 200 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/ReusableBuilder.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/Stack.scala diff --git a/tests/pos-special/stdlib/collection/mutable/ReusableBuilder.scala b/tests/pos-special/stdlib/collection/mutable/ReusableBuilder.scala new file mode 100644 index 000000000000..246e525e37d9 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ReusableBuilder.scala @@ -0,0 +1,56 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import language.experimental.captureChecking + +/** `ReusableBuilder` is a marker trait that indicates that a `Builder` + * can be reused to build more than one instance of a collection. In + * particular, calling `result()` followed by `clear()` will produce a + * collection and reset the builder to begin building a new collection + * of the same type. + * + * In general no method other than `clear()` may be called after `result()`. + * It is up to subclasses to implement and to document other allowed sequences + * of operations (e.g. calling other methods after `result()` in order to obtain + * different snapshots of a collection under construction). + * + * @tparam Elem the type of elements that get added to the builder. + * @tparam To the type of collection that it produced. + * + * @define multipleResults + * + * This Builder can be reused after calling `result()` without an + * intermediate call to `clear()` in order to build multiple related results. + */ +trait ReusableBuilder[-Elem, +To] extends Builder[Elem, To] { + /** Clears the contents of this builder. + * After execution of this method, the builder will contain no elements. + * + * If executed immediately after a call to `result()`, this allows a new + * instance of the same type of collection to be built. + */ + override def clear(): Unit // Note: overriding for Scaladoc only! + + /** Produces a collection from the added elements. + * + * After a call to `result`, the behavior of all other methods is undefined + * save for `clear()`. If `clear()` is called, then the builder is reset and + * may be used to build another instance. + * + * @return a collection containing the elements added to this builder. + */ + override def result(): To // Note: overriding for Scaladoc only! +} diff --git a/tests/pos-special/stdlib/collection/mutable/Stack.scala b/tests/pos-special/stdlib/collection/mutable/Stack.scala new file mode 100644 index 000000000000..d39afe4d099e --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/Stack.scala @@ -0,0 +1,144 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.mutable + +import scala.annotation.{migration, nowarn} +import scala.collection.generic.DefaultSerializable +import scala.collection.{IterableFactoryDefaults, IterableOnce, SeqFactory, StrictOptimizedSeqFactory, StrictOptimizedSeqOps} + +import language.experimental.captureChecking + +/** A stack implements a data structure which allows to store and retrieve + * objects in a last-in-first-out (LIFO) fashion. + * + * Note that operations which consume and produce iterables preserve order, + * rather than reversing it (as would be expected from building a new stack + * by pushing an element at a time). + * + * @tparam A type of the elements contained in this stack. + * + * @define Coll `Stack` + * @define coll stack + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@migration("Stack is now based on an ArrayDeque instead of a linked list", "2.13.0") +class Stack[sealed A] protected (array: Array[AnyRef], start: Int, end: Int) + extends ArrayDeque[A](array, start, end) + with IndexedSeqOps[A, Stack, Stack[A]] + with StrictOptimizedSeqOps[A, Stack, Stack[A]] + with IterableFactoryDefaults[A, Stack] + with ArrayDequeOps[A, Stack, Stack[A]] + with Cloneable[Stack[A]] + with DefaultSerializable { + + def this(initialSize: Int = ArrayDeque.DefaultInitialSize) = + this(ArrayDeque.alloc(initialSize), start = 0, end = 0) + + override def iterableFactory: SeqFactory[Stack] = Stack + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "Stack" + + /** + * Add elements to the top of this stack + * + * @param elem + * @return + */ + def push(elem: A): this.type = prepend(elem) + + /** Push two or more elements onto the stack. The last element + * of the sequence will be on top of the new stack. + * + * @param elems the element sequence. + * @return the stack with the new elements on top. + */ + def push(elem1: A, elem2: A, elems: A*): this.type = { + val k = elems.knownSize + ensureSize(length + (if(k >= 0) k + 2 else 3)) + prepend(elem1).prepend(elem2).pushAll(elems) + } + + /** Push all elements in the given iterable object onto the stack. The + * last element in the iterable object will be on top of the new stack. + * + * @param elems the iterable object. + * @return the stack with the new elements on top. + */ + def pushAll(elems: scala.collection.IterableOnce[A]): this.type = + prependAll(elems match { + case it: scala.collection.Seq[A] => it.view.reverse + case it => IndexedSeq.from(it).view.reverse + }) + + /** + * Removes the top element from this stack and return it + * + * @return + * @throws NoSuchElementException when stack is empty + */ + def pop(): A = removeHead() + + /** + * Pop all elements from this stack and return it + * + * @return The removed elements + */ + def popAll(): scala.collection.Seq[A] = removeAll() + + /** + * Returns and removes all elements from the top of this stack which satisfy the given predicate + * + * @param f the predicate used for choosing elements + * @return The removed elements + */ + def popWhile(f: A => Boolean): scala.collection.Seq[A] = removeHeadWhile(f) + + /** Returns the top element of the stack. This method will not remove + * the element from the stack. An error is signaled if there is no + * element on the stack. + * + * @throws NoSuchElementException + * @return the top element + */ + @`inline` final def top: A = head + + override protected def klone(): Stack[A] = { + val bf = newSpecificBuilder + bf ++= this + bf.result() + } + + override protected def ofArray(array: Array[AnyRef], end: Int): Stack[A] = + new Stack(array, start = 0, end) + +} + +/** + * $factoryInfo + * @define coll stack + * @define Coll `Stack` + */ +@SerialVersionUID(3L) +object Stack extends StrictOptimizedSeqFactory[Stack] { + + def from[sealed A](source: IterableOnce[A]): Stack[A] = empty ++= source + + def empty[sealed A]: Stack[A] = new Stack + + def newBuilder[sealed A]: Builder[A, Stack[A]] = new GrowableBuilder[A, Stack[A]](empty) + +} From 0bf190359bd0e98e5b61225d4486fccda3d9c86c Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:28:07 +0100 Subject: [PATCH 24/89] Add Set.scala to stdlib --- tests/pos-special/stdlib/collection/Set.scala | 269 ++++++++++++++++++ 1 file changed, 269 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/Set.scala diff --git a/tests/pos-special/stdlib/collection/Set.scala b/tests/pos-special/stdlib/collection/Set.scala new file mode 100644 index 000000000000..0ea1e5689473 --- /dev/null +++ b/tests/pos-special/stdlib/collection/Set.scala @@ -0,0 +1,269 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.util.hashing.MurmurHash3 +import java.lang.String + +import scala.annotation.nowarn + +/** Base trait for set collections. + */ +trait Set[A] + extends Iterable[A] + with SetOps[A, Set, Set[A]] + with Equals + with IterableFactoryDefaults[A, Set] { + + def canEqual(that: Any) = true + + /** + * Equality of sets is implemented using the lookup method [[contains]]. This method returns `true` if + * - the argument `that` is a `Set`, + * - the two sets have the same [[size]], and + * - for every `element` this set, `other.contains(element) == true`. + * + * The implementation of `equals` checks the [[canEqual]] method, so subclasses of `Set` can narrow down the equality + * to specific set types. The `Set` implementations in the standard library can all be compared, their `canEqual` + * methods return `true`. + * + * Note: The `equals` method only respects the equality laws (symmetry, transitivity) if the two sets use the same + * element equivalence function in their lookup operation. For example, the element equivalence operation in a + * [[scala.collection.immutable.TreeSet]] is defined by its ordering. Comparing a `TreeSet` with a `HashSet` leads + * to unexpected results if `ordering.equiv(e1, e2)` (used for lookup in `TreeSet`) is different from `e1 == e2` + * (used for lookup in `HashSet`). + * + * {{{ + * scala> import scala.collection.immutable._ + * scala> val ord: Ordering[String] = _ compareToIgnoreCase _ + * + * scala> TreeSet("A")(ord) == HashSet("a") + * val res0: Boolean = false + * + * scala> HashSet("a") == TreeSet("A")(ord) + * val res1: Boolean = true + * }}} + * + * + * @param that The set to which this set is compared + * @return `true` if the two sets are equal according to the description + */ + override def equals(that: Any): Boolean = + (this eq that.asInstanceOf[AnyRef]) || (that match { + case set: Set[A @unchecked] if set.canEqual(this) => + (this.size == set.size) && { + try this.subsetOf(set) + catch { case _: ClassCastException => false } // PR #9565 / scala/bug#12228 + } + case _ => + false + }) + + override def hashCode(): Int = MurmurHash3.setHash(this) + + override def iterableFactory: IterableFactory[Set] = Set + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "Set" + + override def toString(): String = super[Iterable].toString() // Because `Function1` overrides `toString` too +} + +/** Base trait for set operations + * + * @define coll set + * @define Coll `Set` + */ +trait SetOps[A, +CC[_], +C <: SetOps[A, CC, C]] + extends IterableOps[A, CC, C] + with (A => Boolean) { + + def contains(elem: A): Boolean + + /** Tests if some element is contained in this set. + * + * This method is equivalent to `contains`. It allows sets to be interpreted as predicates. + * @param elem the element to test for membership. + * @return `true` if `elem` is contained in this set, `false` otherwise. + */ + @`inline` final def apply(elem: A): Boolean = this.contains(elem) + + /** Tests whether this set is a subset of another set. + * + * @param that the set to test. + * @return `true` if this set is a subset of `that`, i.e. if + * every element of this set is also an element of `that`. + */ + def subsetOf(that: Set[A]): Boolean = this.forall(that) + + /** An iterator over all subsets of this set of the given size. + * If the requested size is impossible, an empty iterator is returned. + * + * @param len the size of the subsets. + * @return the iterator. + */ + def subsets(len: Int): Iterator[C] = { + if (len < 0 || len > size) Iterator.empty + else new SubsetsItr(this.to(IndexedSeq), len) + } + + /** An iterator over all subsets of this set. + * + * @return the iterator. + */ + def subsets(): Iterator[C] = new AbstractIterator[C] { + private[this] val elms = SetOps.this.to(IndexedSeq) + private[this] var len = 0 + private[this] var itr: Iterator[C] = Iterator.empty + + def hasNext = len <= elms.size || itr.hasNext + def next() = { + if (!itr.hasNext) { + if (len > elms.size) Iterator.empty.next() + else { + itr = new SubsetsItr(elms, len) + len += 1 + } + } + + itr.next() + } + } + + /** An Iterator including all subsets containing exactly len elements. + * If the elements in 'This' type is ordered, then the subsets will also be in the same order. + * ListSet(1,2,3).subsets => {{1},{2},{3},{1,2},{1,3},{2,3},{1,2,3}} + * + * $willForceEvaluation + * + */ + private class SubsetsItr(elms: IndexedSeq[A], len: Int) extends AbstractIterator[C] { + private[this] val idxs = Array.range(0, len+1) + private[this] var _hasNext = true + idxs(len) = elms.size + + def hasNext = _hasNext + @throws[NoSuchElementException] + def next(): C = { + if (!hasNext) Iterator.empty.next() + + val buf = newSpecificBuilder + idxs.slice(0, len) foreach (idx => buf += elms(idx)) + val result = buf.result() + + var i = len - 1 + while (i >= 0 && idxs(i) == idxs(i+1)-1) i -= 1 + + if (i < 0) _hasNext = false + else { + idxs(i) += 1 + for (j <- (i+1) until len) + idxs(j) = idxs(j-1) + 1 + } + + result + } + } + + /** Computes the intersection between this set and another set. + * + * @param that the set to intersect with. + * @return a new set consisting of all elements that are both in this + * set and in the given set `that`. + */ + def intersect(that: Set[A]): C = this.filter(that) + + /** Alias for `intersect` */ + @`inline` final def & (that: Set[A]): C = intersect(that) + + /** Computes the difference of this set and another set. + * + * @param that the set of elements to exclude. + * @return a set containing those elements of this + * set that are not also contained in the given set `that`. + */ + def diff(that: Set[A]): C + + /** Alias for `diff` */ + @`inline` final def &~ (that: Set[A]): C = this diff that + + @deprecated("Consider requiring an immutable Set", "2.13.0") + def -- (that: IterableOnce[A]): C = { + val toRemove = that.iterator.to(immutable.Set) + fromSpecific(view.filterNot(toRemove)) + } + + @deprecated("Consider requiring an immutable Set or fall back to Set.diff", "2.13.0") + def - (elem: A): C = diff(Set(elem)) + + @deprecated("Use &- with an explicit collection argument instead of - with varargs", "2.13.0") + def - (elem1: A, elem2: A, elems: A*): C = diff(elems.toSet + elem1 + elem2) + + /** Creates a new $coll by adding all elements contained in another collection to this $coll, omitting duplicates. + * + * This method takes a collection of elements and adds all elements, omitting duplicates, into $coll. + * + * Example: + * {{{ + * scala> val a = Set(1, 2) concat Set(2, 3) + * a: scala.collection.immutable.Set[Int] = Set(1, 2, 3) + * }}} + * + * @param that the collection containing the elements to add. + * @return a new $coll with the given elements added, omitting duplicates. + */ + def concat(that: collection.IterableOnce[A]): C = this match { + case optimizedSet @ (_ : scala.collection.immutable.Set.Set1[A] | _: scala.collection.immutable.Set.Set2[A] | _: scala.collection.immutable.Set.Set3[A] | _: scala.collection.immutable.Set.Set4[A]) => + // StrictOptimizedSetOps optimization of concat (these Sets cannot extend StrictOptimizedSetOps because of binary-incompatible return type; cf. PR #10036) + var result = optimizedSet.asInstanceOf[scala.collection.immutable.SetOps[A, scala.collection.immutable.Set, scala.collection.immutable.Set[A]]] + val it = that.iterator + while (it.hasNext) result = result + it.next() + result.asInstanceOf[C] + case _ => fromSpecific(that match { + case that: collection.Iterable[A] => new View.Concat(this, that) + case _ => iterator.concat(that.iterator) + }) + } + + @deprecated("Consider requiring an immutable Set or fall back to Set.union", "2.13.0") + def + (elem: A): C = fromSpecific(new View.Appended(this, elem)) + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + def + (elem1: A, elem2: A, elems: A*): C = fromSpecific(new View.Concat(new View.Appended(new View.Appended(this, elem1), elem2), elems)) + + /** Alias for `concat` */ + @`inline` final def ++ (that: collection.IterableOnce[A]): C = concat(that) + + /** Computes the union between of set and another set. + * + * @param that the set to form the union with. + * @return a new set consisting of all elements that are in this + * set or in the given set `that`. + */ + @`inline` final def union(that: Set[A]): C = concat(that) + + /** Alias for `union` */ + @`inline` final def | (that: Set[A]): C = concat(that) +} + +/** + * $factoryInfo + * @define coll set + * @define Coll `Set` + */ +@SerialVersionUID(3L) +object Set extends IterableFactory.Delegate[Set](immutable.Set) + +/** Explicit instantiation of the `Set` trait to reduce class file size in subclasses. */ +abstract class AbstractSet[A] extends AbstractIterable[A] with Set[A] From 35e71668f8bbbc737643800a2f550517c1532a00 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:33:38 +0100 Subject: [PATCH 25/89] Make collection/Set capture checked --- tests/pos-special/stdlib/collection/Set.scala | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/tests/pos-special/stdlib/collection/Set.scala b/tests/pos-special/stdlib/collection/Set.scala index 0ea1e5689473..75707f204c02 100644 --- a/tests/pos-special/stdlib/collection/Set.scala +++ b/tests/pos-special/stdlib/collection/Set.scala @@ -17,6 +17,7 @@ import scala.util.hashing.MurmurHash3 import java.lang.String import scala.annotation.nowarn +import language.experimental.captureChecking /** Base trait for set collections. */ @@ -25,6 +26,7 @@ trait Set[A] with SetOps[A, Set, Set[A]] with Equals with IterableFactoryDefaults[A, Set] { + self: Set[A] => def canEqual(that: Any) = true @@ -86,8 +88,7 @@ trait Set[A] * @define Coll `Set` */ trait SetOps[A, +CC[_], +C <: SetOps[A, CC, C]] - extends IterableOps[A, CC, C] - with (A => Boolean) { + extends IterableOps[A, CC, C], (A -> Boolean) { self => def contains(elem: A): Boolean @@ -234,7 +235,7 @@ trait SetOps[A, +CC[_], +C <: SetOps[A, CC, C]] case that: collection.Iterable[A] => new View.Concat(this, that) case _ => iterator.concat(that.iterator) }) - } + } @deprecated("Consider requiring an immutable Set or fall back to Set.union", "2.13.0") def + (elem: A): C = fromSpecific(new View.Appended(this, elem)) From 14b5093fa961c4c2f0a75a4d333dcdb6bd203646 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:35:03 +0100 Subject: [PATCH 26/89] Add mutable/immutable Set to stdlib --- .../stdlib/collection/immutable/Set.scala | 398 ++++++++++++++++++ .../stdlib/collection/mutable/Set.scala | 122 ++++++ 2 files changed, 520 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/Set.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/Set.scala diff --git a/tests/pos-special/stdlib/collection/immutable/Set.scala b/tests/pos-special/stdlib/collection/immutable/Set.scala new file mode 100644 index 000000000000..f07eb66991c8 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/Set.scala @@ -0,0 +1,398 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.collection.immutable.Set.Set4 +import scala.collection.mutable.{Builder, ReusableBuilder} + +/** Base trait for immutable set collections */ +trait Set[A] extends Iterable[A] + with collection.Set[A] + with SetOps[A, Set, Set[A]] + with IterableFactoryDefaults[A, Set] { + override def iterableFactory: IterableFactory[Set] = Set +} + +/** Base trait for immutable set operations + * + * @define coll immutable set + * @define Coll `immutable.Set` + */ +trait SetOps[A, +CC[X], +C <: SetOps[A, CC, C]] + extends collection.SetOps[A, CC, C] { + + /** Creates a new set with an additional element, unless the element is + * already present. + * + * @param elem the element to be added + * @return a new set that contains all elements of this set and that also + * contains `elem`. + */ + def incl(elem: A): C + + /** Alias for `incl` */ + override final def + (elem: A): C = incl(elem) // like in collection.Set but not deprecated + + /** Creates a new set with a given element removed from this set. + * + * @param elem the element to be removed + * @return a new set that contains all elements of this set but that does not + * contain `elem`. + */ + def excl(elem: A): C + + /** Alias for `excl` */ + @`inline` final override def - (elem: A): C = excl(elem) + + def diff(that: collection.Set[A]): C = + foldLeft(empty)((result, elem) => if (that contains elem) result else result + elem) + + /** Creates a new $coll from this $coll by removing all elements of another + * collection. + * + * @param that the collection containing the elements to remove. + * @return a new $coll with the given elements removed, omitting duplicates. + */ + def removedAll(that: IterableOnce[A]): C = that.iterator.foldLeft[C](coll)(_ - _) + + /** Alias for removedAll */ + override final def -- (that: IterableOnce[A]): C = removedAll(that) +} + +trait StrictOptimizedSetOps[A, +CC[X], +C <: SetOps[A, CC, C]] + extends SetOps[A, CC, C] + with collection.StrictOptimizedSetOps[A, CC, C] + with StrictOptimizedIterableOps[A, CC, C] { + + override def concat(that: collection.IterableOnce[A]): C = { + var result: C = coll + val it = that.iterator + while (it.hasNext) result = result + it.next() + result + } +} + +/** + * $factoryInfo + * @define coll immutable set + * @define Coll `immutable.Set` + */ +@SerialVersionUID(3L) +object Set extends IterableFactory[Set] { + + def empty[A]: Set[A] = EmptySet.asInstanceOf[Set[A]] + + def from[E](it: collection.IterableOnce[E]): Set[E] = + it match { + // We want `SortedSet` (and subclasses, such as `BitSet`) to + // rebuild themselves to avoid element type widening issues + case _: SortedSet[E] => (newBuilder[E] ++= it).result() + case _ if it.knownSize == 0 => empty[E] + case s: Set[E] => s + case _ => (newBuilder[E] ++= it).result() + } + + def newBuilder[A]: Builder[A, Set[A]] = new SetBuilderImpl[A] + + /** An optimized representation for immutable empty sets */ + @SerialVersionUID(3L) + private object EmptySet extends AbstractSet[Any] with Serializable { + override def size: Int = 0 + override def isEmpty = true + override def knownSize: Int = size + override def filter(pred: Any => Boolean): Set[Any] = this + override def filterNot(pred: Any => Boolean): Set[Any] = this + override def removedAll(that: IterableOnce[Any]): Set[Any] = this + override def diff(that: collection.Set[Any]): Set[Any] = this + override def subsetOf(that: collection.Set[Any]): Boolean = true + override def intersect(that: collection.Set[Any]): Set[Any] = this + override def view: View[Any] = View.empty + def contains(elem: Any): Boolean = false + def incl(elem: Any): Set[Any] = new Set1(elem) + def excl(elem: Any): Set[Any] = this + def iterator: Iterator[Any] = Iterator.empty + override def foreach[U](f: Any => U): Unit = () + } + private[collection] def emptyInstance: Set[Any] = EmptySet + + @SerialVersionUID(3L) + private abstract class SetNIterator[A](n: Int) extends AbstractIterator[A] with Serializable { + private[this] var current = 0 + private[this] var remainder = n + override def knownSize: Int = remainder + def hasNext = remainder > 0 + def apply(i: Int): A + def next(): A = + if (hasNext) { + val r = apply(current) + current += 1 + remainder -= 1 + r + } else Iterator.empty.next() + + override def drop(n: Int): Iterator[A] = { + if (n > 0) { + current += n + remainder = Math.max(0, remainder - n) + } + this + } + } + + /** An optimized representation for immutable sets of size 1 */ + @SerialVersionUID(3L) + final class Set1[A] private[collection] (elem1: A) extends AbstractSet[A] with StrictOptimizedIterableOps[A, Set, Set[A]] with Serializable { + override def size: Int = 1 + override def isEmpty = false + override def knownSize: Int = size + def contains(elem: A): Boolean = elem == elem1 + def incl(elem: A): Set[A] = + if (contains(elem)) this + else new Set2(elem1, elem) + def excl(elem: A): Set[A] = + if (elem == elem1) Set.empty + else this + def iterator: Iterator[A] = Iterator.single(elem1) + override def foreach[U](f: A => U): Unit = f(elem1) + override def exists(p: A => Boolean): Boolean = p(elem1) + override def forall(p: A => Boolean): Boolean = p(elem1) + override protected[collection] def filterImpl(pred: A => Boolean, isFlipped: Boolean): Set[A] = + if (pred(elem1) != isFlipped) this else Set.empty + + override def find(p: A => Boolean): Option[A] = + if (p(elem1)) Some(elem1) + else None + override def head: A = elem1 + override def tail: Set[A] = Set.empty + } + + /** An optimized representation for immutable sets of size 2 */ + @SerialVersionUID(3L) + final class Set2[A] private[collection] (elem1: A, elem2: A) extends AbstractSet[A] with StrictOptimizedIterableOps[A, Set, Set[A]] with Serializable { + override def size: Int = 2 + override def isEmpty = false + override def knownSize: Int = size + def contains(elem: A): Boolean = elem == elem1 || elem == elem2 + def incl(elem: A): Set[A] = + if (contains(elem)) this + else new Set3(elem1, elem2, elem) + def excl(elem: A): Set[A] = + if (elem == elem1) new Set1(elem2) + else if (elem == elem2) new Set1(elem1) + else this + def iterator: Iterator[A] = new SetNIterator[A](size) { + def apply(i: Int) = getElem(i) + } + private def getElem(i: Int) = i match { case 0 => elem1 case 1 => elem2 } + + override def foreach[U](f: A => U): Unit = { + f(elem1); f(elem2) + } + override def exists(p: A => Boolean): Boolean = { + p(elem1) || p(elem2) + } + override def forall(p: A => Boolean): Boolean = { + p(elem1) && p(elem2) + } + override protected[collection] def filterImpl(pred: A => Boolean, isFlipped: Boolean): Set[A] = { + var r1: A = null.asInstanceOf[A] + var n = 0 + if (pred(elem1) != isFlipped) { r1 = elem1; n += 1} + if (pred(elem2) != isFlipped) { if (n == 0) r1 = elem2; n += 1} + + n match { + case 0 => Set.empty + case 1 => new Set1(r1) + case 2 => this + } + } + override def find(p: A => Boolean): Option[A] = { + if (p(elem1)) Some(elem1) + else if (p(elem2)) Some(elem2) + else None + } + override def head: A = elem1 + override def tail: Set[A] = new Set1(elem2) + } + + /** An optimized representation for immutable sets of size 3 */ + @SerialVersionUID(3L) + final class Set3[A] private[collection] (elem1: A, elem2: A, elem3: A) extends AbstractSet[A] with StrictOptimizedIterableOps[A, Set, Set[A]] with Serializable { + override def size: Int = 3 + override def isEmpty = false + override def knownSize: Int = size + def contains(elem: A): Boolean = + elem == elem1 || elem == elem2 || elem == elem3 + def incl(elem: A): Set[A] = + if (contains(elem)) this + else new Set4(elem1, elem2, elem3, elem) + def excl(elem: A): Set[A] = + if (elem == elem1) new Set2(elem2, elem3) + else if (elem == elem2) new Set2(elem1, elem3) + else if (elem == elem3) new Set2(elem1, elem2) + else this + def iterator: Iterator[A] = new SetNIterator[A](size) { + def apply(i: Int) = getElem(i) + } + private def getElem(i: Int) = i match { case 0 => elem1 case 1 => elem2 case 2 => elem3 } + + override def foreach[U](f: A => U): Unit = { + f(elem1); f(elem2); f(elem3) + } + override def exists(p: A => Boolean): Boolean = { + p(elem1) || p(elem2) || p(elem3) + } + override def forall(p: A => Boolean): Boolean = { + p(elem1) && p(elem2) && p(elem3) + } + override protected[collection] def filterImpl(pred: A => Boolean, isFlipped: Boolean): Set[A] = { + var r1, r2: A = null.asInstanceOf[A] + var n = 0 + if (pred(elem1) != isFlipped) { r1 = elem1; n += 1} + if (pred(elem2) != isFlipped) { if (n == 0) r1 = elem2 else r2 = elem2; n += 1} + if (pred(elem3) != isFlipped) { if (n == 0) r1 = elem3 else if (n == 1) r2 = elem3; n += 1} + + n match { + case 0 => Set.empty + case 1 => new Set1(r1) + case 2 => new Set2(r1, r2) + case 3 => this + } + } + override def find(p: A => Boolean): Option[A] = { + if (p(elem1)) Some(elem1) + else if (p(elem2)) Some(elem2) + else if (p(elem3)) Some(elem3) + else None + } + override def head: A = elem1 + override def tail: Set[A] = new Set2(elem2, elem3) + } + + /** An optimized representation for immutable sets of size 4 */ + @SerialVersionUID(3L) + final class Set4[A] private[collection] (elem1: A, elem2: A, elem3: A, elem4: A) extends AbstractSet[A] with StrictOptimizedIterableOps[A, Set, Set[A]] with Serializable { + override def size: Int = 4 + override def isEmpty = false + override def knownSize: Int = size + def contains(elem: A): Boolean = + elem == elem1 || elem == elem2 || elem == elem3 || elem == elem4 + def incl(elem: A): Set[A] = + if (contains(elem)) this + else HashSet.empty[A] + elem1 + elem2 + elem3 + elem4 + elem + def excl(elem: A): Set[A] = + if (elem == elem1) new Set3(elem2, elem3, elem4) + else if (elem == elem2) new Set3(elem1, elem3, elem4) + else if (elem == elem3) new Set3(elem1, elem2, elem4) + else if (elem == elem4) new Set3(elem1, elem2, elem3) + else this + def iterator: Iterator[A] = new SetNIterator[A](size) { + def apply(i: Int) = getElem(i) + } + private def getElem(i: Int) = i match { case 0 => elem1 case 1 => elem2 case 2 => elem3 case 3 => elem4 } + + override def foreach[U](f: A => U): Unit = { + f(elem1); f(elem2); f(elem3); f(elem4) + } + override def exists(p: A => Boolean): Boolean = { + p(elem1) || p(elem2) || p(elem3) || p(elem4) + } + override def forall(p: A => Boolean): Boolean = { + p(elem1) && p(elem2) && p(elem3) && p(elem4) + } + override protected[collection] def filterImpl(pred: A => Boolean, isFlipped: Boolean): Set[A] = { + var r1, r2, r3: A = null.asInstanceOf[A] + var n = 0 + if (pred(elem1) != isFlipped) { r1 = elem1; n += 1} + if (pred(elem2) != isFlipped) { if (n == 0) r1 = elem2 else r2 = elem2; n += 1} + if (pred(elem3) != isFlipped) { if (n == 0) r1 = elem3 else if (n == 1) r2 = elem3 else r3 = elem3; n += 1} + if (pred(elem4) != isFlipped) { if (n == 0) r1 = elem4 else if (n == 1) r2 = elem4 else if (n == 2) r3 = elem4; n += 1} + + n match { + case 0 => Set.empty + case 1 => new Set1(r1) + case 2 => new Set2(r1, r2) + case 3 => new Set3(r1, r2, r3) + case 4 => this + } + } + + override def find(p: A => Boolean): Option[A] = { + if (p(elem1)) Some(elem1) + else if (p(elem2)) Some(elem2) + else if (p(elem3)) Some(elem3) + else if (p(elem4)) Some(elem4) + else None + } + override def head: A = elem1 + override def tail: Set[A] = new Set3(elem2, elem3, elem4) + + private[immutable] def buildTo(builder: Builder[A, Set[A]]): builder.type = + builder.addOne(elem1).addOne(elem2).addOne(elem3).addOne(elem4) + } +} + +/** Explicit instantiation of the `Set` trait to reduce class file size in subclasses. */ +abstract class AbstractSet[A] extends scala.collection.AbstractSet[A] with Set[A] + +/** Builder for Set. + * $multipleResults + */ +private final class SetBuilderImpl[A] extends ReusableBuilder[A, Set[A]] { + private[this] var elems: Set[A] = Set.empty + private[this] var switchedToHashSetBuilder: Boolean = false + private[this] var hashSetBuilder: HashSetBuilder[A] = _ + + override def clear(): Unit = { + elems = Set.empty + if (hashSetBuilder != null) { + hashSetBuilder.clear() + } + switchedToHashSetBuilder = false + } + + override def result(): Set[A] = + if (switchedToHashSetBuilder) hashSetBuilder.result() else elems + + def addOne(elem: A) = { + if (switchedToHashSetBuilder) { + hashSetBuilder.addOne(elem) + } else if (elems.size < 4) { + elems = elems + elem + } else { + // assert(elems.size == 4) + if (elems.contains(elem)) { + () // do nothing + } else { + switchedToHashSetBuilder = true + if (hashSetBuilder == null) { + hashSetBuilder = new HashSetBuilder + } + elems.asInstanceOf[Set4[A]].buildTo(hashSetBuilder) + hashSetBuilder.addOne(elem) + } + } + + this + } + + override def addAll(xs: IterableOnce[A]): this.type = + if (switchedToHashSetBuilder) { + hashSetBuilder.addAll(xs) + this + } else { + super.addAll(xs) + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/Set.scala b/tests/pos-special/stdlib/collection/mutable/Set.scala new file mode 100644 index 000000000000..6530e8fedf05 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/Set.scala @@ -0,0 +1,122 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.mutable + +import scala.collection.{IterableFactory, IterableFactoryDefaults, IterableOps} + +/** Base trait for mutable sets */ +trait Set[A] + extends Iterable[A] + with collection.Set[A] + with SetOps[A, Set, Set[A]] + with IterableFactoryDefaults[A, Set] { + + override def iterableFactory: IterableFactory[Set] = Set +} + +/** + * @define coll mutable set + * @define Coll `mutable.Set` + */ +trait SetOps[A, +CC[X], +C <: SetOps[A, CC, C]] + extends collection.SetOps[A, CC, C] + with IterableOps[A, CC, C] // only needed so we can use super[IterableOps] below + with Cloneable[C] + with Builder[A, C] + with Growable[A] + with Shrinkable[A] { + + def result(): C = coll + + /** Check whether the set contains the given element, and add it if not. + * + * @param elem the element to be added + * @return true if the element was added + */ + def add(elem: A): Boolean = + !contains(elem) && { + coll += elem; true + } + + /** Updates the presence of a single element in this set. + * + * This method allows one to add or remove an element `elem` + * from this set depending on the value of parameter `included`. + * Typically, one would use the following syntax: + * {{{ + * set(elem) = true // adds element + * set(elem) = false // removes element + * }}} + * + * @param elem the element to be added or removed + * @param included a flag indicating whether element should be included or excluded. + */ + def update(elem: A, included: Boolean): Unit = { + if (included) add(elem) + else remove(elem) + } + + /** Removes an element from this set. + * + * @param elem the element to be removed + * @return true if this set contained the element before it was removed + */ + def remove(elem: A): Boolean = { + val res = contains(elem) + coll -= elem + res + } + + def diff(that: collection.Set[A]): C = + foldLeft(empty)((result, elem) => if (that contains elem) result else result += elem) + + @deprecated("Use filterInPlace instead", "2.13.0") + @inline final def retain(p: A => Boolean): Unit = filterInPlace(p) + + /** Removes all elements from the set for which do not satisfy a predicate. + * @param p the predicate used to test elements. Only elements for + * which `p` returns `true` are retained in the set; all others + * are removed. + */ + def filterInPlace(p: A => Boolean): this.type = { + if (nonEmpty) { + val array = this.toArray[Any] // scala/bug#7269 toArray avoids ConcurrentModificationException + val arrayLength = array.length + var i = 0 + while (i < arrayLength) { + val elem = array(i).asInstanceOf[A] + if (!p(elem)) { + this -= elem + } + i += 1 + } + } + this + } + + override def clone(): C = empty ++= this + + override def knownSize: Int = super[IterableOps].knownSize +} + +/** + * $factoryInfo + * @define coll mutable set + * @define Coll `mutable.Set` + */ +@SerialVersionUID(3L) +object Set extends IterableFactory.Delegate[Set](HashSet) + + +/** Explicit instantiation of the `Set` trait to reduce class file size in subclasses. */ +abstract class AbstractSet[A] extends scala.collection.AbstractSet[A] with Set[A] From 1f414a3b9d13890ccfe67becb8cb222371042f3c Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:40:53 +0100 Subject: [PATCH 27/89] Make mutable/immutable Set capture checked --- .../stdlib/collection/immutable/Set.scala | 12 +++++++----- .../pos-special/stdlib/collection/mutable/Set.scala | 1 + 2 files changed, 8 insertions(+), 5 deletions(-) diff --git a/tests/pos-special/stdlib/collection/immutable/Set.scala b/tests/pos-special/stdlib/collection/immutable/Set.scala index f07eb66991c8..ac92f81b2013 100644 --- a/tests/pos-special/stdlib/collection/immutable/Set.scala +++ b/tests/pos-special/stdlib/collection/immutable/Set.scala @@ -16,6 +16,8 @@ package immutable import scala.collection.immutable.Set.Set4 import scala.collection.mutable.{Builder, ReusableBuilder} +import language.experimental.captureChecking +import annotation.unchecked.uncheckedCaptures /** Base trait for immutable set collections */ trait Set[A] extends Iterable[A] @@ -94,7 +96,7 @@ object Set extends IterableFactory[Set] { def empty[A]: Set[A] = EmptySet.asInstanceOf[Set[A]] - def from[E](it: collection.IterableOnce[E]): Set[E] = + def from[E](it: collection.IterableOnce[E]^): Set[E] = it match { // We want `SortedSet` (and subclasses, such as `BitSet`) to // rebuild themselves to avoid element type widening issues @@ -128,7 +130,7 @@ object Set extends IterableFactory[Set] { private[collection] def emptyInstance: Set[Any] = EmptySet @SerialVersionUID(3L) - private abstract class SetNIterator[A](n: Int) extends AbstractIterator[A] with Serializable { + private abstract class SetNIterator[A](n: Int) extends AbstractIterator[A], Serializable, Pure { private[this] var current = 0 private[this] var remainder = n override def knownSize: Int = remainder @@ -351,9 +353,9 @@ abstract class AbstractSet[A] extends scala.collection.AbstractSet[A] with Set[A * $multipleResults */ private final class SetBuilderImpl[A] extends ReusableBuilder[A, Set[A]] { - private[this] var elems: Set[A] = Set.empty + private[this] var elems: Set[A @uncheckedCaptures] = Set.empty private[this] var switchedToHashSetBuilder: Boolean = false - private[this] var hashSetBuilder: HashSetBuilder[A] = _ + private[this] var hashSetBuilder: HashSetBuilder[A @uncheckedCaptures] = _ override def clear(): Unit = { elems = Set.empty @@ -388,7 +390,7 @@ private final class SetBuilderImpl[A] extends ReusableBuilder[A, Set[A]] { this } - override def addAll(xs: IterableOnce[A]): this.type = + override def addAll(xs: IterableOnce[A]^): this.type = if (switchedToHashSetBuilder) { hashSetBuilder.addAll(xs) this diff --git a/tests/pos-special/stdlib/collection/mutable/Set.scala b/tests/pos-special/stdlib/collection/mutable/Set.scala index 6530e8fedf05..01384e993e89 100644 --- a/tests/pos-special/stdlib/collection/mutable/Set.scala +++ b/tests/pos-special/stdlib/collection/mutable/Set.scala @@ -13,6 +13,7 @@ package scala.collection.mutable import scala.collection.{IterableFactory, IterableFactoryDefaults, IterableOps} +import language.experimental.captureChecking /** Base trait for mutable sets */ trait Set[A] From f92c881562dedd6da200617f4f222f84e24c5525 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:48:19 +0100 Subject: [PATCH 28/89] Add BitSet classes to stdlib (capture checked) --- .../stdlib/collection/BitSet.scala | 348 ++++++++++++++++ .../stdlib/collection/immutable/BitSet.scala | 376 +++++++++++++++++ .../stdlib/collection/mutable/BitSet.scala | 393 ++++++++++++++++++ 3 files changed, 1117 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/BitSet.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/BitSet.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/BitSet.scala diff --git a/tests/pos-special/stdlib/collection/BitSet.scala b/tests/pos-special/stdlib/collection/BitSet.scala new file mode 100644 index 000000000000..62326dfd2152 --- /dev/null +++ b/tests/pos-special/stdlib/collection/BitSet.scala @@ -0,0 +1,348 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import java.io.{ObjectInputStream, ObjectOutputStream} + +import scala.annotation.nowarn +import scala.collection.Stepper.EfficientSplit +import scala.collection.mutable.Builder +import language.experimental.captureChecking + +/** Base type of bitsets. + * + * This trait provides most of the operations of a `BitSet` independently of its representation. + * It is inherited by all concrete implementations of bitsets. + * + * @define bitsetinfo + * Bitsets are sets of non-negative integers which are represented as + * variable-size arrays of bits packed into 64-bit words. The lower bound of memory footprint of a bitset is + * determined by the largest number stored in it. + * @define coll bitset + * @define Coll `BitSet` + */ +trait BitSet extends SortedSet[Int] with BitSetOps[BitSet] { + override protected def fromSpecific(coll: IterableOnce[Int]^): BitSet = bitSetFactory.fromSpecific(coll) + override protected def newSpecificBuilder: Builder[Int, BitSet] = bitSetFactory.newBuilder + override def empty: BitSet = bitSetFactory.empty + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "BitSet" + override def unsorted: Set[Int] = this +} + +@SerialVersionUID(3L) +object BitSet extends SpecificIterableFactory[Int, BitSet] { + private[collection] final val ordMsg = "No implicit Ordering[${B}] found to build a SortedSet[${B}]. You may want to upcast to a Set[Int] first by calling `unsorted`." + private[collection] final val zipOrdMsg = "No implicit Ordering[${B}] found to build a SortedSet[(Int, ${B})]. You may want to upcast to a Set[Int] first by calling `unsorted`." + + def empty: BitSet = immutable.BitSet.empty + def newBuilder: Builder[Int, BitSet] = immutable.BitSet.newBuilder + def fromSpecific(it: IterableOnce[Int]): BitSet = immutable.BitSet.fromSpecific(it) + + @SerialVersionUID(3L) + private[collection] abstract class SerializationProxy(@transient protected val coll: BitSet) extends Serializable { + + @transient protected var elems: Array[Long] = _ + + private[this] def writeObject(out: ObjectOutputStream): Unit = { + out.defaultWriteObject() + val nwords = coll.nwords + out.writeInt(nwords) + var i = 0 + while(i < nwords) { + out.writeLong(coll.word(i)) + i += 1 + } + } + + private[this] def readObject(in: ObjectInputStream): Unit = { + in.defaultReadObject() + val nwords = in.readInt() + elems = new Array[Long](nwords) + var i = 0 + while(i < nwords) { + elems(i) = in.readLong() + i += 1 + } + } + + protected[this] def readResolve(): Any + } +} + +/** Base implementation type of bitsets */ +trait BitSetOps[+C <: BitSet with BitSetOps[C]] + extends SortedSetOps[Int, SortedSet, C] { self => + import BitSetOps._ + + def bitSetFactory: SpecificIterableFactory[Int, C] + + def unsorted: Set[Int] + + final def ordering: Ordering[Int] = Ordering.Int + + /** The number of words (each with 64 bits) making up the set */ + protected[collection] def nwords: Int + + /** The words at index `idx`, or 0L if outside the range of the set + * '''Note:''' requires `idx >= 0` + */ + protected[collection] def word(idx: Int): Long + + /** Creates a new set of this kind from an array of longs + */ + protected[collection] def fromBitMaskNoCopy(elems: Array[Long]): C + + def contains(elem: Int): Boolean = + 0 <= elem && (word(elem >> LogWL) & (1L << elem)) != 0L + + def iterator: Iterator[Int] = iteratorFrom(0) + + def iteratorFrom(start: Int): Iterator[Int] = new AbstractIterator[Int] { + private[this] var currentPos = if (start > 0) start >> LogWL else 0 + private[this] var currentWord = if (start > 0) word(currentPos) & (-1L << (start & (WordLength - 1))) else word(0) + final override def hasNext: Boolean = { + while (currentWord == 0) { + if (currentPos + 1 >= nwords) return false + currentPos += 1 + currentWord = word(currentPos) + } + true + } + final override def next(): Int = { + if (hasNext) { + val bitPos = java.lang.Long.numberOfTrailingZeros(currentWord) + currentWord &= currentWord - 1 + (currentPos << LogWL) + bitPos + } else Iterator.empty.next() + } + } + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Int, S]): S with EfficientSplit = { + val st = scala.collection.convert.impl.BitSetStepper.from(this) + val r = + if (shape.shape == StepperShape.IntShape) st + else { + assert(shape.shape == StepperShape.ReferenceShape, s"unexpected StepperShape: $shape") + AnyStepper.ofParIntStepper(st) + } + r.asInstanceOf[S with EfficientSplit] + } + + override def size: Int = { + var s = 0 + var i = nwords + while (i > 0) { + i -= 1 + s += java.lang.Long.bitCount(word(i)) + } + s + } + + override def isEmpty: Boolean = 0 until nwords forall (i => word(i) == 0) + + @inline private[this] def smallestInt: Int = { + val thisnwords = nwords + var i = 0 + while(i < thisnwords) { + val currentWord = word(i) + if (currentWord != 0L) { + return java.lang.Long.numberOfTrailingZeros(currentWord) + (i * WordLength) + } + i += 1 + } + throw new UnsupportedOperationException("empty.smallestInt") + } + + @inline private[this] def largestInt: Int = { + var i = nwords - 1 + while(i >= 0) { + val currentWord = word(i) + if (currentWord != 0L) { + return ((i + 1) * WordLength) - java.lang.Long.numberOfLeadingZeros(currentWord) - 1 + } + i -= 1 + } + throw new UnsupportedOperationException("empty.largestInt") + } + + override def max[B >: Int](implicit ord: Ordering[B]): Int = + if (Ordering.Int eq ord) largestInt + else if (Ordering.Int isReverseOf ord) smallestInt + else super.max(ord) + + + override def min[B >: Int](implicit ord: Ordering[B]): Int = + if (Ordering.Int eq ord) smallestInt + else if (Ordering.Int isReverseOf ord) largestInt + else super.min(ord) + + override def foreach[U](f: Int => U): Unit = { + /* NOTE: while loops are significantly faster as of 2.11 and + one major use case of bitsets is performance. Also, there + is nothing to do when all bits are clear, so use that as + the inner loop condition. */ + var i = 0 + while (i < nwords) { + var w = word(i) + var j = i * WordLength + while (w != 0L) { + if ((w&1L) == 1L) f(j) + w = w >>> 1 + j += 1 + } + i += 1 + } + } + + /** Creates a bit mask for this set as a new array of longs + */ + def toBitMask: Array[Long] = { + val a = new Array[Long](nwords) + var i = a.length + while(i > 0) { + i -= 1 + a(i) = word(i) + } + a + } + + def rangeImpl(from: Option[Int], until: Option[Int]): C = { + val a = coll.toBitMask + val len = a.length + if (from.isDefined) { + val f = from.get + val w = f >> LogWL + val b = f & (WordLength - 1) + if (w >= 0) { + java.util.Arrays.fill(a, 0, math.min(w, len), 0) + if (b > 0 && w < len) a(w) &= ~((1L << b) - 1) + } + } + if (until.isDefined) { + val u = until.get + val w = u >> LogWL + val b = u & (WordLength - 1) + if (w < len) { + java.util.Arrays.fill(a, math.max(w + 1, 0), len, 0) + if (w >= 0) a(w) &= (1L << b) - 1 + } + } + coll.fromBitMaskNoCopy(a) + } + + override def concat(other: collection.IterableOnce[Int]): C = other match { + case otherBitset: BitSet => + val len = coll.nwords max otherBitset.nwords + val words = new Array[Long](len) + for (idx <- 0 until len) + words(idx) = this.word(idx) | otherBitset.word(idx) + fromBitMaskNoCopy(words) + case _ => super.concat(other) + } + + override def intersect(other: Set[Int]): C = other match { + case otherBitset: BitSet => + val len = coll.nwords min otherBitset.nwords + val words = new Array[Long](len) + for (idx <- 0 until len) + words(idx) = this.word(idx) & otherBitset.word(idx) + fromBitMaskNoCopy(words) + case _ => super.intersect(other) + } + + abstract override def diff(other: Set[Int]): C = other match { + case otherBitset: BitSet => + val len = coll.nwords + val words = new Array[Long](len) + for (idx <- 0 until len) + words(idx) = this.word(idx) & ~otherBitset.word(idx) + fromBitMaskNoCopy(words) + case _ => super.diff(other) + } + + /** Computes the symmetric difference of this bitset and another bitset by performing + * a bitwise "exclusive-or". + * + * @param other the other bitset to take part in the symmetric difference. + * @return a bitset containing those bits of this + * bitset or the other bitset that are not contained in both bitsets. + */ + def xor(other: BitSet): C = { + val len = coll.nwords max other.nwords + val words = new Array[Long](len) + for (idx <- 0 until len) + words(idx) = coll.word(idx) ^ other.word(idx) + coll.fromBitMaskNoCopy(words) + } + + @`inline` final def ^ (other: BitSet): C = xor(other) + + /** + * Builds a new bitset by applying a function to all elements of this bitset + * @param f the function to apply to each element. + * @return a new bitset resulting from applying the given function ''f'' to + * each element of this bitset and collecting the results + */ + def map(f: Int => Int): C = fromSpecific(new View.Map(this, f)) + + def flatMap(f: Int => IterableOnce[Int]): C = fromSpecific(new View.FlatMap(this, f)) + + def collect(pf: PartialFunction[Int, Int]): C = fromSpecific(super[SortedSetOps].collect(pf)) + + override def partition(p: Int => Boolean): (C, C) = { + val left = filter(p) + (left, this &~ left) + } +} + +object BitSetOps { + + /* Final vals can sometimes be inlined as constants (faster) */ + private[collection] final val LogWL = 6 + private[collection] final val WordLength = 64 + private[collection] final val MaxSize = (Int.MaxValue >> LogWL) + 1 + + private[collection] def updateArray(elems: Array[Long], idx: Int, w: Long): Array[Long] = { + var len = elems.length + while (len > 0 && (elems(len - 1) == 0L || w == 0L && idx == len - 1)) len -= 1 + var newlen = len + if (idx >= newlen && w != 0L) newlen = idx + 1 + val newelems = new Array[Long](newlen) + Array.copy(elems, 0, newelems, 0, len) + if (idx < newlen) newelems(idx) = w + else assert(w == 0L) + newelems + } + + private[collection] def computeWordForFilter(pred: Int => Boolean, isFlipped: Boolean, oldWord: Long, wordIndex: Int): Long = + if (oldWord == 0L) 0L else { + var w = oldWord + val trailingZeroes = java.lang.Long.numberOfTrailingZeros(w) + var jmask = 1L << trailingZeroes + var j = wordIndex * BitSetOps.WordLength + trailingZeroes + val maxJ = (wordIndex + 1) * BitSetOps.WordLength - java.lang.Long.numberOfLeadingZeros(w) + while (j != maxJ) { + if ((w & jmask) != 0L) { + if (pred(j) == isFlipped) { + // j did not pass the filter here + w = w & ~jmask + } + } + jmask = jmask << 1 + j += 1 + } + w + } +} diff --git a/tests/pos-special/stdlib/collection/immutable/BitSet.scala b/tests/pos-special/stdlib/collection/immutable/BitSet.scala new file mode 100644 index 000000000000..109f32d6f49a --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/BitSet.scala @@ -0,0 +1,376 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import BitSetOps.{LogWL, updateArray} +import mutable.Builder +import scala.annotation.{implicitNotFound, nowarn} +import language.experimental.captureChecking + +/** A class for immutable bitsets. + * $bitsetinfo + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#immutable-bitsets "Scala's Collection Library overview"]] + * section on `Immutable BitSets` for more information. + * + * @define Coll `immutable.BitSet` + * @define coll immutable bitset + */ +sealed abstract class BitSet + extends AbstractSet[Int] + with SortedSet[Int] + with SortedSetOps[Int, SortedSet, BitSet] + with StrictOptimizedSortedSetOps[Int, SortedSet, BitSet] + with collection.BitSet + with collection.BitSetOps[BitSet] + with Serializable { + + override def unsorted: Set[Int] = this + + override protected def fromSpecific(coll: IterableOnce[Int]^): BitSet = bitSetFactory.fromSpecific(coll) + override protected def newSpecificBuilder: Builder[Int, BitSet] = bitSetFactory.newBuilder + override def empty: BitSet = bitSetFactory.empty + + def bitSetFactory = BitSet + + protected[collection] def fromBitMaskNoCopy(elems: Array[Long]): BitSet = BitSet.fromBitMaskNoCopy(elems) + + def incl(elem: Int): BitSet = { + require(elem >= 0, "bitset element must be >= 0") + if (contains(elem)) this + else { + val idx = elem >> LogWL + updateWord(idx, word(idx) | (1L << elem)) + } + } + + def excl(elem: Int): BitSet = { + require(elem >= 0, "bitset element must be >= 0") + if (contains(elem)) { + val idx = elem >> LogWL + updateWord(idx, word(idx) & ~(1L << elem)) + } else this + } + + /** Update word at index `idx`; enlarge set if `idx` outside range of set. + */ + protected def updateWord(idx: Int, w: Long): BitSet + + override def map(f: Int => Int): BitSet = strictOptimizedMap(newSpecificBuilder, f) + override def map[B](f: Int => B)(implicit @implicitNotFound(collection.BitSet.ordMsg) ev: Ordering[B]): SortedSet[B] = + super[StrictOptimizedSortedSetOps].map(f) + + override def flatMap(f: Int => IterableOnce[Int]): BitSet = strictOptimizedFlatMap(newSpecificBuilder, f) + override def flatMap[B](f: Int => IterableOnce[B])(implicit @implicitNotFound(collection.BitSet.ordMsg) ev: Ordering[B]): SortedSet[B] = + super[StrictOptimizedSortedSetOps].flatMap(f) + + override def collect(pf: PartialFunction[Int, Int]): BitSet = strictOptimizedCollect(newSpecificBuilder, pf) + override def collect[B](pf: scala.PartialFunction[Int, B])(implicit @implicitNotFound(collection.BitSet.ordMsg) ev: Ordering[B]): SortedSet[B] = + super[StrictOptimizedSortedSetOps].collect(pf) + + // necessary for disambiguation + override def zip[B](that: scala.IterableOnce[B])(implicit @implicitNotFound(collection.BitSet.zipOrdMsg) ev: Ordering[(Int, B)]): SortedSet[(Int, B)] = + super.zip(that) + + protected[this] def writeReplace(): AnyRef = new BitSet.SerializationProxy(this) +} + +/** + * $factoryInfo + * @define Coll `immutable.BitSet` + * @define coll immutable bitset + */ +@nowarn("cat=deprecation&msg=Implementation classes of BitSet should not be accessed directly") +@SerialVersionUID(3L) +object BitSet extends SpecificIterableFactory[Int, BitSet] { + + def fromSpecific(it: scala.collection.IterableOnce[Int]): BitSet = + it match { + case bs: BitSet => bs + case _ => (newBuilder ++= it).result() + } + + final val empty: BitSet = new BitSet1(0L) + + def newBuilder: Builder[Int, BitSet] = + mutable.BitSet.newBuilder.mapResult(bs => fromBitMaskNoCopy(bs.elems)) + + private def createSmall(a: Long, b: Long): BitSet = if (b == 0L) new BitSet1(a) else new BitSet2(a, b) + + /** A bitset containing all the bits in an array */ + def fromBitMask(elems: Array[Long]): BitSet = { + val len = elems.length + if (len == 0) empty + else if (len == 1) new BitSet1(elems(0)) + else if (len == 2) createSmall(elems(0), elems(1)) + else { + val a = java.util.Arrays.copyOf(elems, len) + new BitSetN(a) + } + } + + /** A bitset containing all the bits in an array, wrapping the existing + * array without copying. + */ + def fromBitMaskNoCopy(elems: Array[Long]): BitSet = { + val len = elems.length + if (len == 0) empty + else if (len == 1) new BitSet1(elems(0)) + else if (len == 2) createSmall(elems(0), elems(1)) + else new BitSetN(elems) + } + + @deprecated("Implementation classes of BitSet should not be accessed directly", "2.13.0") + class BitSet1(val elems: Long) extends BitSet { + protected[collection] def nwords = 1 + protected[collection] def word(idx: Int) = if (idx == 0) elems else 0L + protected[collection] def updateWord(idx: Int, w: Long): BitSet = + if (idx == 0) new BitSet1(w) + else if (idx == 1) createSmall(elems, w) + else this.fromBitMaskNoCopy(updateArray(Array(elems), idx, w)) + + + override def diff(other: collection.Set[Int]): BitSet = other match { + case bs: collection.BitSet => bs.nwords match { + case 0 => this + case _ => + val newElems = elems & ~bs.word(0) + if (newElems == 0L) this.empty else new BitSet1(newElems) + } + case _ => super.diff(other) + } + + override def filterImpl(pred: Int => Boolean, isFlipped: Boolean): BitSet = { + val _elems = BitSetOps.computeWordForFilter(pred, isFlipped, elems, 0) + if (_elems == 0L) this.empty else new BitSet1(_elems) + } + } + + @deprecated("Implementation classes of BitSet should not be accessed directly", "2.13.0") + class BitSet2(val elems0: Long, val elems1: Long) extends BitSet { + protected[collection] def nwords = 2 + protected[collection] def word(idx: Int) = if (idx == 0) elems0 else if (idx == 1) elems1 else 0L + protected[collection] def updateWord(idx: Int, w: Long): BitSet = + if (idx == 0) new BitSet2(w, elems1) + else if (idx == 1) createSmall(elems0, w) + else this.fromBitMaskNoCopy(updateArray(Array(elems0, elems1), idx, w)) + + + override def diff(other: collection.Set[Int]): BitSet = other match { + case bs: collection.BitSet => bs.nwords match { + case 0 => this + case 1 => + new BitSet2(elems0 & ~bs.word(0), elems1) + case _ => + val _elems0 = elems0 & ~bs.word(0) + val _elems1 = elems1 & ~bs.word(1) + + if (_elems1 == 0L) { + if (_elems0 == 0L) { + this.empty + } else { + new BitSet1(_elems0) + } + } else { + new BitSet2(_elems0, _elems1) + } + } + case _ => super.diff(other) + } + + override def filterImpl(pred: Int => Boolean, isFlipped: Boolean): BitSet = { + val _elems0 = BitSetOps.computeWordForFilter(pred, isFlipped, elems0, 0) + val _elems1 = BitSetOps.computeWordForFilter(pred, isFlipped, elems1, 1) + + if (_elems1 == 0L) { + if (_elems0 == 0L) { + this.empty + } + else new BitSet1(_elems0) + } + else new BitSet2(_elems0, _elems1) + } + } + + @deprecated("Implementation classes of BitSet should not be accessed directly", "2.13.0") + class BitSetN(val elems: Array[Long]) extends BitSet { + protected[collection] def nwords = elems.length + + protected[collection] def word(idx: Int) = if (idx < nwords) elems(idx) else 0L + + protected[collection] def updateWord(idx: Int, w: Long): BitSet = this.fromBitMaskNoCopy(updateArray(elems, idx, w)) + + override def diff(that: collection.Set[Int]): BitSet = that match { + case bs: collection.BitSet => + /* + * Algorithm: + * + * We iterate, word-by-word, backwards from the shortest of the two bitsets (this, or bs) i.e. the one with + * the fewer words. Two extra concerns for optimization are described below. + * + * Array Shrinking: + * If `this` is not longer than `bs`, then since we must iterate through the full array of words, + * we can track the new highest index word which is non-zero, at little additional cost. At the end, the new + * Array[Long] allocated for the returned BitSet will only be of size `maxNonZeroIndex + 1` + * + * Tracking Changes: + * If the two sets are disjoint, then we can return `this`. Therefor, until at least one change is detected, + * we check each word for if it has changed from its corresponding word in `this`. Once a single change is + * detected, we stop checking because the cost of the new Array must be paid anyways. + */ + + val bsnwords = bs.nwords + val thisnwords = nwords + if (bsnwords >= thisnwords) { + // here, we may have opportunity to shrink the size of the array + // so, track the highest index which is non-zero. That ( + 1 ) will be our new array length + var i = thisnwords - 1 + var currentWord = 0L + // if there are never any changes, we can return `this` at the end + var anyChanges = false + while (i >= 0 && currentWord == 0L) { + val oldWord = word(i) + currentWord = oldWord & ~bs.word(i) + anyChanges ||= currentWord != oldWord + i -= 1 + } + i match { + case -1 => + if (anyChanges) { + if (currentWord == 0) { + this.empty + } else { + new BitSet1(currentWord) + } + } else { + this + } + case 0 => + val oldFirstWord = word(0) + val firstWord = oldFirstWord & ~bs.word(0) + anyChanges ||= firstWord != oldFirstWord + if (anyChanges) { + new BitSet2(firstWord, currentWord) + } else { + this + } + case _ => + val minimumNonZeroIndex: Int = i + 1 + while (!anyChanges && i >= 0) { + val oldWord = word(i) + currentWord = oldWord & ~bs.word(i) + anyChanges ||= currentWord != oldWord + i -= 1 + } + if (anyChanges) { + val newArray = elems.take(minimumNonZeroIndex + 1) + newArray(i + 1) = currentWord + while (i >= 0) { + newArray(i) = word(i) & ~bs.word(i) + i -= 1 + } + new BitSetN(newArray) + } else { + this + } + } + } else { + var i = bsnwords - 1 + var anyChanges = false + var currentWord = 0L + while (i >= 0 && !anyChanges) { + val oldWord = word(i) + currentWord = oldWord & ~bs.word(i) + anyChanges ||= currentWord != oldWord + i -= 1 + } + if (anyChanges) { + val newElems = elems.clone() + newElems(i + 1) = currentWord + while (i >= 0) { + newElems(i) = word(i) & ~bs.word(i) + i -= 1 + } + this.fromBitMaskNoCopy(newElems) + } else { + this + } + } + case _ => super.diff(that) + } + + + override def filterImpl(pred: Int => Boolean, isFlipped: Boolean): BitSet = { + // here, we may have opportunity to shrink the size of the array + // so, track the highest index which is non-zero. That ( + 1 ) will be our new array length + var i = nwords - 1 + var currentWord = 0L + // if there are never any changes, we can return `this` at the end + var anyChanges = false + while (i >= 0 && currentWord == 0L) { + val oldWord = word(i) + currentWord = BitSetOps.computeWordForFilter(pred, isFlipped, oldWord, i) + anyChanges ||= currentWord != oldWord + i -= 1 + } + i match { + case -1 => + if (anyChanges) { + if (currentWord == 0) { + this.empty + } else { + new BitSet1(currentWord) + } + } else { + this + } + case 0 => + val oldFirstWord = word(0) + val firstWord = BitSetOps.computeWordForFilter(pred, isFlipped, oldFirstWord, 0) + anyChanges ||= firstWord != oldFirstWord + if (anyChanges) { + new BitSet2(firstWord, currentWord) + } else { + this + } + case _ => + val minimumNonZeroIndex: Int = i + 1 + while (!anyChanges && i >= 0) { + val oldWord = word(i) + currentWord = BitSetOps.computeWordForFilter(pred, isFlipped, oldWord, i) + anyChanges ||= currentWord != oldWord + i -= 1 + } + if (anyChanges) { + val newArray = elems.take(minimumNonZeroIndex + 1) + newArray(i + 1) = currentWord + while (i >= 0) { + newArray(i) = BitSetOps.computeWordForFilter(pred, isFlipped, word(i), i) + i -= 1 + } + new BitSetN(newArray) + } else { + this + } + } + } + + override def toBitMask: Array[Long] = elems.clone() + } + + @SerialVersionUID(3L) + private final class SerializationProxy(coll: BitSet) extends scala.collection.BitSet.SerializationProxy(coll) { + protected[this] def readResolve(): Any = BitSet.fromBitMaskNoCopy(elems) + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/BitSet.scala b/tests/pos-special/stdlib/collection/mutable/BitSet.scala new file mode 100644 index 000000000000..17005fd16a9f --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/BitSet.scala @@ -0,0 +1,393 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.collection.immutable.Range +import BitSetOps.{LogWL, MaxSize} +import scala.annotation.implicitNotFound +import language.experimental.captureChecking + +/** + * A class for mutable bitsets. + * + * $bitsetinfo + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#mutable-bitsets "Scala's Collection Library overview"]] + * section on `Mutable Bitsets` for more information. + * + * @define Coll `BitSet` + * @define coll bitset + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +class BitSet(protected[collection] final var elems: Array[Long]) + extends AbstractSet[Int] + with SortedSet[Int] + with SortedSetOps[Int, SortedSet, BitSet] + with StrictOptimizedIterableOps[Int, Set, BitSet] + with StrictOptimizedSortedSetOps[Int, SortedSet, BitSet] + with collection.BitSet + with collection.BitSetOps[BitSet] + with Serializable { + + def this(initSize: Int) = this(new Array[Long](math.max((initSize + 63) >> 6, 1))) + + def this() = this(0) + + override protected def fromSpecific(coll: IterableOnce[Int]^): BitSet = bitSetFactory.fromSpecific(coll) + override protected def newSpecificBuilder: Builder[Int, BitSet] = bitSetFactory.newBuilder + override def empty: BitSet = bitSetFactory.empty + + def bitSetFactory = BitSet + + override def unsorted: Set[Int] = this + + protected[collection] final def nwords: Int = elems.length + + protected[collection] final def word(idx: Int): Long = + if (idx < nwords) elems(idx) else 0L + + protected[collection] def fromBitMaskNoCopy(elems: Array[Long]): BitSet = + if (elems.length == 0) empty + else new BitSet(elems) + + def addOne(elem: Int): this.type = { + require(elem >= 0) + if (!contains(elem)) { + val idx = elem >> LogWL + updateWord(idx, word(idx) | (1L << elem)) + } + this + } + + def subtractOne(elem: Int): this.type = { + require(elem >= 0) + if (contains(elem)) { + val idx = elem >> LogWL + updateWord(idx, word(idx) & ~(1L << elem)) + } + this + } + + def clear(): Unit = { + elems = new Array[Long](elems.length) + } + + protected final def updateWord(idx: Int, w: Long): Unit = { + ensureCapacity(idx) + elems(idx) = w + } + + protected final def ensureCapacity(idx: Int): Unit = { + require(idx < MaxSize) + if (idx >= nwords) { + var newlen = nwords + while (idx >= newlen) newlen = math.min(newlen * 2, MaxSize) + val elems1 = new Array[Long](newlen) + Array.copy(elems, 0, elems1, 0, nwords) + elems = elems1 + } + } + + def unconstrained: collection.Set[Int] = this + + /** Updates this bitset to the union with another bitset by performing a bitwise "or". + * + * @param other the bitset to form the union with. + * @return the bitset itself. + */ + def |= (other: collection.BitSet): this.type = { + ensureCapacity(other.nwords - 1) + var i = 0 + val othernwords = other.nwords + while (i < othernwords) { + elems(i) = elems(i) | other.word(i) + i += 1 + } + this + } + /** Updates this bitset to the intersection with another bitset by performing a bitwise "and". + * + * @param other the bitset to form the intersection with. + * @return the bitset itself. + */ + def &= (other: collection.BitSet): this.type = { + // Different from other operations: no need to ensure capacity because + // anything beyond the capacity is 0. Since we use other.word which is 0 + // off the end, we also don't need to make sure we stay in bounds there. + var i = 0 + val thisnwords = nwords + while (i < thisnwords) { + elems(i) = elems(i) & other.word(i) + i += 1 + } + this + } + /** Updates this bitset to the symmetric difference with another bitset by performing a bitwise "xor". + * + * @param other the bitset to form the symmetric difference with. + * @return the bitset itself. + */ + def ^= (other: collection.BitSet): this.type = { + ensureCapacity(other.nwords - 1) + var i = 0 + val othernwords = other.nwords + while (i < othernwords) { + + elems(i) = elems(i) ^ other.word(i) + i += 1 + } + this + } + /** Updates this bitset to the difference with another bitset by performing a bitwise "and-not". + * + * @param other the bitset to form the difference with. + * @return the bitset itself. + */ + def &~= (other: collection.BitSet): this.type = { + var i = 0 + val max = Math.min(nwords, other.nwords) + while (i < max) { + elems(i) = elems(i) & ~other.word(i) + i += 1 + } + this + } + + override def clone(): BitSet = new BitSet(java.util.Arrays.copyOf(elems, elems.length)) + + def toImmutable: immutable.BitSet = immutable.BitSet.fromBitMask(elems) + + override def map(f: Int => Int): BitSet = strictOptimizedMap(newSpecificBuilder, f) + override def map[B](f: Int => B)(implicit @implicitNotFound(collection.BitSet.ordMsg) ev: Ordering[B]): SortedSet[B] = + super[StrictOptimizedSortedSetOps].map(f) + + override def flatMap(f: Int => IterableOnce[Int]): BitSet = strictOptimizedFlatMap(newSpecificBuilder, f) + override def flatMap[B](f: Int => IterableOnce[B])(implicit @implicitNotFound(collection.BitSet.ordMsg) ev: Ordering[B]): SortedSet[B] = + super[StrictOptimizedSortedSetOps].flatMap(f) + + override def collect(pf: PartialFunction[Int, Int]): BitSet = strictOptimizedCollect(newSpecificBuilder, pf) + override def collect[B](pf: scala.PartialFunction[Int, B])(implicit @implicitNotFound(collection.BitSet.ordMsg) ev: Ordering[B]): SortedSet[B] = + super[StrictOptimizedSortedSetOps].collect(pf) + + // necessary for disambiguation + override def zip[B](that: IterableOnce[B])(implicit @implicitNotFound(collection.BitSet.zipOrdMsg) ev: Ordering[(Int, B)]): SortedSet[(Int, B)] = + super.zip(that) + + override def addAll(xs: IterableOnce[Int]^): this.type = xs match { + case bs: collection.BitSet => + this |= bs + case range: Range => + if (range.nonEmpty) { + val start = range.min + if (start >= 0) { + val end = range.max + val endIdx = end >> LogWL + ensureCapacity(endIdx) + + if (range.step == 1 || range.step == -1) { + val startIdx = start >> LogWL + val wordStart = startIdx * BitSetOps.WordLength + val wordMask = -1L << (start - wordStart) + + if (endIdx > startIdx) { + elems(startIdx) |= wordMask + java.util.Arrays.fill(elems, startIdx + 1, endIdx, -1L) + elems(endIdx) |= -1L >>> (BitSetOps.WordLength - (end - endIdx * BitSetOps.WordLength) - 1) + } else elems(endIdx) |= (wordMask & (-1L >>> (BitSetOps.WordLength - (end - wordStart) - 1))) + } else super.addAll(range) + } else super.addAll(range) + } + this + + case sorted: collection.SortedSet[Int] => + // if `sorted` is using the regular Int ordering, ensure capacity for the largest + // element up front to avoid multiple resizing allocations + if (sorted.nonEmpty) { + val ord = sorted.ordering + if (ord eq Ordering.Int) { + ensureCapacity(sorted.lastKey >> LogWL) + } else if (ord eq Ordering.Int.reverse) { + ensureCapacity(sorted.firstKey >> LogWL) + } + val iter = sorted.iterator + while (iter.hasNext) { + addOne(iter.next()) + } + } + + this + + case other => + super.addAll(other) + } + + override def subsetOf(that: collection.Set[Int]): Boolean = that match { + case bs: collection.BitSet => + val thisnwords = this.nwords + val bsnwords = bs.nwords + val minWords = Math.min(thisnwords, bsnwords) + + // if any bits are set to `1` in words out of range of `bs`, then this is not a subset. Start there + var i = bsnwords + while (i < thisnwords) { + if (word(i) != 0L) return false + i += 1 + } + + // the higher range of `this` is all `0`s, fall back to lower range + var j = 0 + while (j < minWords) { + if ((word(j) & ~bs.word(j)) != 0L) return false + j += 1 + } + + true + case other => + super.subsetOf(other) + } + + override def subtractAll(xs: IterableOnce[Int]^): this.type = xs match { + case bs: collection.BitSet => this &~= bs + case other => super.subtractAll(other) + } + + protected[this] def writeReplace(): AnyRef = new BitSet.SerializationProxy(this) + + override def diff(that: collection.Set[Int]): BitSet = that match { + case bs: collection.BitSet => + /* + * Algorithm: + * + * We iterate, word-by-word, backwards from the shortest of the two bitsets (this, or bs) i.e. the one with + * the fewer words. + * + * Array Shrinking: + * If `this` is not longer than `bs`, then since we must iterate through the full array of words, + * we can track the new highest index word which is non-zero, at little additional cost. At the end, the new + * Array[Long] allocated for the returned BitSet will only be of size `maxNonZeroIndex + 1` + */ + + val bsnwords = bs.nwords + val thisnwords = nwords + if (bsnwords >= thisnwords) { + // here, we may have opportunity to shrink the size of the array + // so, track the highest index which is non-zero. That ( + 1 ) will be our new array length + var i = thisnwords - 1 + var currentWord = 0L + + while (i >= 0 && currentWord == 0L) { + val oldWord = word(i) + currentWord = oldWord & ~bs.word(i) + i -= 1 + } + + if (i < 0) { + fromBitMaskNoCopy(Array(currentWord)) + } else { + val minimumNonZeroIndex: Int = i + 1 + val newArray = elems.take(minimumNonZeroIndex + 1) + newArray(i + 1) = currentWord + while (i >= 0) { + newArray(i) = word(i) & ~bs.word(i) + i -= 1 + } + fromBitMaskNoCopy(newArray) + } + } else { + // here, there is no opportunity to shrink the array size, no use in tracking highest non-zero index + val newElems = elems.clone() + var i = bsnwords - 1 + while (i >= 0) { + newElems(i) = word(i) & ~bs.word(i) + i -= 1 + } + fromBitMaskNoCopy(newElems) + } + case _ => super.diff(that) + } + + override def filterImpl(pred: Int => Boolean, isFlipped: Boolean): BitSet = { + // We filter the BitSet from highest to lowest, so we can determine exactly the highest non-zero word + // index which lets us avoid: + // * over-allocating -- the resulting array will be exactly the right size + // * multiple resizing allocations -- the array is allocated one time, not log(n) times. + var i = nwords - 1 + var newArray: Array[Long] = null + while (i >= 0) { + val w = BitSetOps.computeWordForFilter(pred, isFlipped, word(i), i) + if (w != 0L) { + if (newArray eq null) { + newArray = new Array(i + 1) + } + newArray(i) = w + } + i -= 1 + } + if (newArray eq null) { + empty + } else { + fromBitMaskNoCopy(newArray) + } + } + + override def filterInPlace(p: Int => Boolean): this.type = { + val thisnwords = nwords + var i = 0 + while (i < thisnwords) { + elems(i) = BitSetOps.computeWordForFilter(p, isFlipped = false, elems(i), i) + i += 1 + } + this + } + + override def toBitMask: Array[Long] = elems.clone() +} + +@SerialVersionUID(3L) +object BitSet extends SpecificIterableFactory[Int, BitSet] { + + def fromSpecific(it: scala.collection.IterableOnce[Int]): BitSet = Growable.from(empty, it) + + def empty: BitSet = new BitSet() + + def newBuilder: Builder[Int, BitSet] = new GrowableBuilder(empty) + + /** A bitset containing all the bits in an array */ + def fromBitMask(elems: Array[Long]): BitSet = { + val len = elems.length + if (len == 0) empty + else { + val a = java.util.Arrays.copyOf(elems, len) + new BitSet(a) + } + } + + /** A bitset containing all the bits in an array, wrapping the existing + * array without copying. + */ + def fromBitMaskNoCopy(elems: Array[Long]): BitSet = { + val len = elems.length + if (len == 0) empty + else new BitSet(elems) + } + + @SerialVersionUID(3L) + private final class SerializationProxy(coll: BitSet) extends scala.collection.BitSet.SerializationProxy(coll) { + protected[this] def readResolve(): Any = BitSet.fromBitMaskNoCopy(elems) + } +} From 6a831aafdacc2e2de39c3e554573edb04c5331ab Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 17:49:21 +0100 Subject: [PATCH 29/89] Add SortedSet classes to stdlib --- .../stdlib/collection/SortedSet.scala | 189 ++++++++++++++++++ .../collection/immutable/SortedSet.scala | 57 ++++++ .../stdlib/collection/mutable/SortedSet.scala | 48 +++++ 3 files changed, 294 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/SortedSet.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/SortedSet.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/SortedSet.scala diff --git a/tests/pos-special/stdlib/collection/SortedSet.scala b/tests/pos-special/stdlib/collection/SortedSet.scala new file mode 100644 index 000000000000..c98ca9ae5523 --- /dev/null +++ b/tests/pos-special/stdlib/collection/SortedSet.scala @@ -0,0 +1,189 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import scala.annotation.{implicitNotFound, nowarn} +import scala.annotation.unchecked.uncheckedVariance + +/** Base type of sorted sets */ +trait SortedSet[A] extends Set[A] + with SortedSetOps[A, SortedSet, SortedSet[A]] + with SortedSetFactoryDefaults[A, SortedSet, Set] { + + def unsorted: Set[A] = this + + def sortedIterableFactory: SortedIterableFactory[SortedSet] = SortedSet + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "SortedSet" + + override def equals(that: Any): Boolean = that match { + case _ if this eq that.asInstanceOf[AnyRef] => true + case ss: SortedSet[A @unchecked] if ss.ordering == this.ordering => + (ss canEqual this) && + (this.size == ss.size) && { + val i1 = this.iterator + val i2 = ss.iterator + var allEqual = true + while (allEqual && i1.hasNext) + allEqual = ordering.equiv(i1.next(), i2.next()) + allEqual + } + case _ => + super.equals(that) + } + +} + +trait SortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]] + extends SetOps[A, Set, C] + with SortedOps[A, C] { + + /** The companion object of this sorted set, providing various factory methods. + * + * @note When implementing a custom collection type and refining `CC` to the new type, this + * method needs to be overridden to return a factory for the new type (the compiler will + * issue an error otherwise). + */ + def sortedIterableFactory: SortedIterableFactory[CC] + + def unsorted: Set[A] + + /** + * Creates an iterator that contains all values from this collection + * greater than or equal to `start` according to the ordering of + * this collection. x.iteratorFrom(y) is equivalent to but will usually + * be more efficient than x.from(y).iterator + * + * @param start The lower-bound (inclusive) of the iterator + */ + def iteratorFrom(start: A): Iterator[A] + + @deprecated("Use `iteratorFrom` instead.", "2.13.0") + @`inline` def keysIteratorFrom(start: A): Iterator[A] = iteratorFrom(start) + + def firstKey: A = head + def lastKey: A = last + + /** Find the smallest element larger than or equal to a given key. + * @param key The given key. + * @return `None` if there is no such node. + */ + def minAfter(key: A): Option[A] = rangeFrom(key).headOption + + /** Find the largest element less than a given key. + * @param key The given key. + * @return `None` if there is no such node. + */ + def maxBefore(key: A): Option[A] = rangeUntil(key).lastOption + + override def min[B >: A](implicit ord: Ordering[B]): A = + if (isEmpty) throw new UnsupportedOperationException("empty.min") + else if (ord == ordering) head + else if (ord isReverseOf ordering) last + else super.min[B] // need the type annotation for it to infer the correct implicit + + override def max[B >: A](implicit ord: Ordering[B]): A = + if (isEmpty) throw new UnsupportedOperationException("empty.max") + else if (ord == ordering) last + else if (ord isReverseOf ordering) head + else super.max[B] // need the type annotation for it to infer the correct implicit + + def rangeTo(to: A): C = { + val i = rangeFrom(to).iterator + if (i.isEmpty) return coll + val next = i.next() + if (ordering.compare(next, to) == 0) + if (i.isEmpty) coll + else rangeUntil(i.next()) + else + rangeUntil(next) + } + + /** Builds a new sorted collection by applying a function to all elements of this $coll. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned collection. + * @return a new $coll resulting from applying the given function + * `f` to each element of this $coll and collecting the results. + */ + def map[B](f: A => B)(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] = + sortedIterableFactory.from(new View.Map(this, f)) + + /** Builds a new sorted collection by applying a function to all elements of this $coll + * and using the elements of the resulting collections. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned collection. + * @return a new $coll resulting from applying the given collection-valued function + * `f` to each element of this $coll and concatenating the results. + */ + def flatMap[B](f: A => IterableOnce[B])(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] = + sortedIterableFactory.from(new View.FlatMap(this, f)) + + /** Returns a $coll formed from this $coll and another iterable collection + * by combining corresponding elements in pairs. + * If one of the two collections is longer than the other, its remaining elements are ignored. + * + * @param that The iterable providing the second half of each result pair + * @tparam B the type of the second half of the returned pairs + * @return a new $coll containing pairs consisting of corresponding elements of this $coll and `that`. + * The length of the returned collection is the minimum of the lengths of this $coll and `that`. + */ + def zip[B](that: IterableOnce[B])(implicit @implicitNotFound(SortedSetOps.zipOrdMsg) ev: Ordering[(A @uncheckedVariance, B)]): CC[(A @uncheckedVariance, B)] = // sound bcs of VarianceNote + sortedIterableFactory.from(that match { + case that: Iterable[B] => new View.Zip(this, that) + case _ => iterator.zip(that) + }) + + /** Builds a new sorted collection by applying a partial function to all elements of this $coll + * on which the function is defined. + * + * @param pf the partial function which filters and maps the $coll. + * @tparam B the element type of the returned collection. + * @return a new $coll resulting from applying the given partial function + * `pf` to each element on which it is defined and collecting the results. + * The order of the elements is preserved. + */ + def collect[B](pf: scala.PartialFunction[A, B])(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] = + sortedIterableFactory.from(new View.Collect(this, pf)) +} + +object SortedSetOps { + private[collection] final val ordMsg = "No implicit Ordering[${B}] found to build a SortedSet[${B}]. You may want to upcast to a Set[${A}] first by calling `unsorted`." + private[collection] final val zipOrdMsg = "No implicit Ordering[${B}] found to build a SortedSet[(${A}, ${B})]. You may want to upcast to a Set[${A}] first by calling `unsorted`." + + /** Specialize `WithFilter` for sorted collections + * + * @define coll sorted collection + */ + class WithFilter[+A, +IterableCC[_], +CC[X] <: SortedSet[X]]( + self: SortedSetOps[A, CC, _] with IterableOps[A, IterableCC, _], + p: A => Boolean + ) extends IterableOps.WithFilter[A, IterableCC](self, p) { + + def map[B : Ordering](f: A => B): CC[B] = + self.sortedIterableFactory.from(new View.Map(filtered, f)) + + def flatMap[B : Ordering](f: A => IterableOnce[B]): CC[B] = + self.sortedIterableFactory.from(new View.FlatMap(filtered, f)) + + override def withFilter(q: A => Boolean): WithFilter[A, IterableCC, CC] = + new WithFilter[A, IterableCC, CC](self, (a: A) => p(a) && q(a)) + } + +} + +@SerialVersionUID(3L) +object SortedSet extends SortedIterableFactory.Delegate[SortedSet](immutable.SortedSet) + diff --git a/tests/pos-special/stdlib/collection/immutable/SortedSet.scala b/tests/pos-special/stdlib/collection/immutable/SortedSet.scala new file mode 100644 index 000000000000..303e5ea9658c --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/SortedSet.scala @@ -0,0 +1,57 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +/** Base trait for sorted sets */ +trait SortedSet[A] + extends Set[A] + with collection.SortedSet[A] + with SortedSetOps[A, SortedSet, SortedSet[A]] + with SortedSetFactoryDefaults[A, SortedSet, Set] { + + override def unsorted: Set[A] = this + + override def sortedIterableFactory: SortedIterableFactory[SortedSet] = SortedSet +} + +/** + * @define coll immutable sorted set + * @define Coll `immutable.SortedSet` + */ +trait SortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]] + extends SetOps[A, Set, C] + with collection.SortedSetOps[A, CC, C] { + + def unsorted: Set[A] +} + +trait StrictOptimizedSortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]] + extends SortedSetOps[A, CC, C] + with collection.StrictOptimizedSortedSetOps[A, CC, C] + with StrictOptimizedSetOps[A, Set, C] { +} + +/** + * $factoryInfo + * @define coll immutable sorted set + * @define Coll `immutable.SortedSet` + */ +@SerialVersionUID(3L) +object SortedSet extends SortedIterableFactory.Delegate[SortedSet](TreeSet) { + override def from[E: Ordering](it: IterableOnce[E]): SortedSet[E] = it match { + case ss: SortedSet[E] if Ordering[E] == ss.ordering => ss + case _ => super.from(it) + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/SortedSet.scala b/tests/pos-special/stdlib/collection/mutable/SortedSet.scala new file mode 100644 index 000000000000..2bcb8dc7845a --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/SortedSet.scala @@ -0,0 +1,48 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +/** + * Base type for mutable sorted set collections + */ +trait SortedSet[A] + extends Set[A] + with collection.SortedSet[A] + with SortedSetOps[A, SortedSet, SortedSet[A]] + with SortedSetFactoryDefaults[A, SortedSet, Set] { + + override def unsorted: Set[A] = this + + override def sortedIterableFactory: SortedIterableFactory[SortedSet] = SortedSet +} + +/** + * @define coll mutable sorted set + * @define Coll `mutable.Sortedset` + */ +trait SortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]] + extends SetOps[A, Set, C] + with collection.SortedSetOps[A, CC, C] { + + def unsorted: Set[A] +} + +/** + * $factoryInfo + * @define coll mutable sorted set + * @define Coll `mutable.Sortedset` + */ +@SerialVersionUID(3L) +object SortedSet extends SortedIterableFactory.Delegate[SortedSet](TreeSet) From 3b6b6843979d69abcf5bc3310bf0a6425cba11a4 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 22:33:54 +0100 Subject: [PATCH 30/89] Add Factory.scala to stdlib --- .../stdlib/collection/Factory.scala | 784 ++++++++++++++++++ 1 file changed, 784 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/Factory.scala diff --git a/tests/pos-special/stdlib/collection/Factory.scala b/tests/pos-special/stdlib/collection/Factory.scala new file mode 100644 index 000000000000..2b15f1cc15d1 --- /dev/null +++ b/tests/pos-special/stdlib/collection/Factory.scala @@ -0,0 +1,784 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.collection.immutable.NumericRange +import scala.language.implicitConversions +import scala.collection.mutable.Builder +import scala.annotation.unchecked.uncheckedVariance +import scala.reflect.ClassTag + +/** + * A factory that builds a collection of type `C` with elements of type `A`. + * + * This is a general form of any factory ([[IterableFactory]], + * [[SortedIterableFactory]], [[MapFactory]] and [[SortedMapFactory]]) whose + * element type is fixed. + * + * @tparam A Type of elements (e.g. `Int`, `Boolean`, etc.) + * @tparam C Type of collection (e.g. `List[Int]`, `TreeMap[Int, String]`, etc.) + */ +trait Factory[-A, +C] extends Any { + + /** + * @return A collection of type `C` containing the same elements + * as the source collection `it`. + * @param it Source collection + */ + def fromSpecific(it: IterableOnce[A]): C + + /** Get a Builder for the collection. For non-strict collection types this will use an intermediate buffer. + * Building collections with `fromSpecific` is preferred because it can be lazy for lazy collections. */ + def newBuilder: Builder[A, C] +} + +object Factory { + + implicit val stringFactory: Factory[Char, String] = new StringFactory + @SerialVersionUID(3L) + private class StringFactory extends Factory[Char, String] with Serializable { + def fromSpecific(it: IterableOnce[Char]): String = { + val b = new mutable.StringBuilder(scala.math.max(0, it.knownSize)) + b ++= it + b.result() + } + def newBuilder: Builder[Char, String] = new mutable.StringBuilder() + } + + implicit def arrayFactory[A: ClassTag]: Factory[A, Array[A]] = new ArrayFactory[A] + @SerialVersionUID(3L) + private class ArrayFactory[A: ClassTag] extends Factory[A, Array[A]] with Serializable { + def fromSpecific(it: IterableOnce[A]): Array[A] = { + val b = newBuilder + b.sizeHint(scala.math.max(0, it.knownSize)) + b ++= it + b.result() + } + def newBuilder: Builder[A, Array[A]] = mutable.ArrayBuilder.make[A] + } + +} + +/** Base trait for companion objects of unconstrained collection types that may require + * multiple traversals of a source collection to build a target collection `CC`. + * + * @tparam CC Collection type constructor (e.g. `List`) + * @define factoryInfo + * This object provides a set of operations to create $Coll values. + * + * @define coll collection + * @define Coll `Iterable` + */ +trait IterableFactory[+CC[_]] extends Serializable { + + /** Creates a target $coll from an existing source collection + * + * @param source Source collection + * @tparam A the type of the collection’s elements + * @return a new $coll with the elements of `source` + */ + def from[A](source: IterableOnce[A]): CC[A] + + /** An empty collection + * @tparam A the type of the ${coll}'s elements + */ + def empty[A]: CC[A] + + /** Creates a $coll with the specified elements. + * @tparam A the type of the ${coll}'s elements + * @param elems the elements of the created $coll + * @return a new $coll with elements `elems` + */ + def apply[A](elems: A*): CC[A] = from(elems) + + /** Produces a $coll containing repeated applications of a function to a start value. + * + * @param start the start value of the $coll + * @param len the number of elements contained in the $coll + * @param f the function that's repeatedly applied + * @return a $coll with `len` values in the sequence `start, f(start), f(f(start)), ...` + */ + def iterate[A](start: A, len: Int)(f: A => A): CC[A] = from(new View.Iterate(start, len)(f)) + + /** Produces a $coll that uses a function `f` to produce elements of type `A` + * and update an internal state of type `S`. + * + * @param init State initial value + * @param f Computes the next element (or returns `None` to signal + * the end of the collection) + * @tparam A Type of the elements + * @tparam S Type of the internal state + * @return a $coll that produces elements using `f` until `f` returns `None` + */ + def unfold[A, S](init: S)(f: S => Option[(A, S)]): CC[A] = from(new View.Unfold(init)(f)) + + /** Produces a $coll containing a sequence of increasing of integers. + * + * @param start the first element of the $coll + * @param end the end value of the $coll (the first value NOT contained) + * @return a $coll with values `start, start + 1, ..., end - 1` + */ + def range[A : Integral](start: A, end: A): CC[A] = from(NumericRange(start, end, implicitly[Integral[A]].one)) + + /** Produces a $coll containing equally spaced values in some integer interval. + * @param start the start value of the $coll + * @param end the end value of the $coll (the first value NOT contained) + * @param step the difference between successive elements of the $coll (must be positive or negative) + * @return a $coll with values `start, start + step, ...` up to, but excluding `end` + */ + def range[A : Integral](start: A, end: A, step: A): CC[A] = from(NumericRange(start, end, step)) + + /** + * @return A builder for $Coll objects. + * @tparam A the type of the ${coll}’s elements + */ + def newBuilder[A]: Builder[A, CC[A]] + + /** Produces a $coll containing the results of some element computation a number of times. + * @param n the number of elements contained in the $coll. + * @param elem the element computation + * @return A $coll that contains the results of `n` evaluations of `elem`. + */ + def fill[A](n: Int)(elem: => A): CC[A] = from(new View.Fill(n)(elem)) + + /** Produces a two-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2` evaluations of `elem`. + */ + def fill[A](n1: Int, n2: Int)(elem: => A): CC[CC[A] @uncheckedVariance] = fill(n1)(fill(n2)(elem)) + + /** Produces a three-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2 x n3` evaluations of `elem`. + */ + def fill[A](n1: Int, n2: Int, n3: Int)(elem: => A): CC[CC[CC[A]] @uncheckedVariance] = fill(n1)(fill(n2, n3)(elem)) + + /** Produces a four-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2 x n3 x n4` evaluations of `elem`. + */ + def fill[A](n1: Int, n2: Int, n3: Int, n4: Int)(elem: => A): CC[CC[CC[CC[A]]] @uncheckedVariance] = + fill(n1)(fill(n2, n3, n4)(elem)) + + /** Produces a five-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param n5 the number of elements in the 5th dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2 x n3 x n4 x n5` evaluations of `elem`. + */ + def fill[A](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(elem: => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance] = + fill(n1)(fill(n2, n3, n4, n5)(elem)) + + /** Produces a $coll containing values of a given function over a range of integer values starting from 0. + * @param n The number of elements in the $coll + * @param f The function computing element values + * @return A $coll consisting of elements `f(0), ..., f(n -1)` + */ + def tabulate[A](n: Int)(f: Int => A): CC[A] = from(new View.Tabulate(n)(f)) + + /** Produces a two-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2)` + * for `0 <= i1 < n1` and `0 <= i2 < n2`. + */ + def tabulate[A](n1: Int, n2: Int)(f: (Int, Int) => A): CC[CC[A] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2)(f(i1, _))) + + /** Produces a three-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2, i3)` + * for `0 <= i1 < n1`, `0 <= i2 < n2`, and `0 <= i3 < n3`. + */ + def tabulate[A](n1: Int, n2: Int, n3: Int)(f: (Int, Int, Int) => A): CC[CC[CC[A]] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2, n3)(f(i1, _, _))) + + /** Produces a four-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2, i3, i4)` + * for `0 <= i1 < n1`, `0 <= i2 < n2`, `0 <= i3 < n3`, and `0 <= i4 < n4`. + */ + def tabulate[A](n1: Int, n2: Int, n3: Int, n4: Int)(f: (Int, Int, Int, Int) => A): CC[CC[CC[CC[A]]] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2, n3, n4)(f(i1, _, _, _))) + + /** Produces a five-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param n5 the number of elements in the 5th dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2, i3, i4, i5)` + * for `0 <= i1 < n1`, `0 <= i2 < n2`, `0 <= i3 < n3`, `0 <= i4 < n4`, and `0 <= i5 < n5`. + */ + def tabulate[A](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(f: (Int, Int, Int, Int, Int) => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2, n3, n4, n5)(f(i1, _, _, _, _))) + + /** Concatenates all argument collections into a single $coll. + * + * @param xss the collections that are to be concatenated. + * @return the concatenation of all the collections. + */ + def concat[A](xss: Iterable[A]*): CC[A] = { + from(xss.foldLeft(View.empty[A])(_ ++ _)) + } + + implicit def iterableFactory[A]: Factory[A, CC[A]] = IterableFactory.toFactory(this) +} + +object IterableFactory { + + /** + * Fixes the element type of `factory` to `A` + * @param factory The factory to fix the element type + * @tparam A Type of elements + * @tparam CC Collection type constructor of the factory (e.g. `Seq`, `List`) + * @return A [[Factory]] that uses the given `factory` to build a collection of elements + * of type `A` + */ + implicit def toFactory[A, CC[_]](factory: IterableFactory[CC]): Factory[A, CC[A]] = new ToFactory[A, CC](factory) + + @SerialVersionUID(3L) + private[this] class ToFactory[A, CC[_]](factory: IterableFactory[CC]) extends Factory[A, CC[A]] with Serializable { + def fromSpecific(it: IterableOnce[A]): CC[A] = factory.from[A](it) + def newBuilder: Builder[A, CC[A]] = factory.newBuilder[A] + } + + implicit def toBuildFrom[A, CC[_]](factory: IterableFactory[CC]): BuildFrom[Any, A, CC[A]] = + new BuildFrom[Any, A, CC[A]] { + def fromSpecific(from: Any)(it: IterableOnce[A]) = factory.from(it) + def newBuilder(from: Any) = factory.newBuilder + } + + @SerialVersionUID(3L) + class Delegate[CC[_]](delegate: IterableFactory[CC]) extends IterableFactory[CC] { + override def apply[A](elems: A*): CC[A] = delegate.apply(elems: _*) + def empty[A]: CC[A] = delegate.empty + def from[E](it: IterableOnce[E]): CC[E] = delegate.from(it) + def newBuilder[A]: Builder[A, CC[A]] = delegate.newBuilder[A] + } +} + +/** + * @tparam CC Collection type constructor (e.g. `List`) + */ +trait SeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends IterableFactory[CC] { + import SeqFactory.UnapplySeqWrapper + final def unapplySeq[A](x: CC[A] @uncheckedVariance): UnapplySeqWrapper[A] = new UnapplySeqWrapper(x) // TODO is uncheckedVariance sound here? +} + +object SeqFactory { + @SerialVersionUID(3L) + class Delegate[CC[A] <: SeqOps[A, Seq, Seq[A]]](delegate: SeqFactory[CC]) extends SeqFactory[CC] { + override def apply[A](elems: A*): CC[A] = delegate.apply(elems: _*) + def empty[A]: CC[A] = delegate.empty + def from[E](it: IterableOnce[E]): CC[E] = delegate.from(it) + def newBuilder[A]: Builder[A, CC[A]] = delegate.newBuilder[A] + } + + final class UnapplySeqWrapper[A](private val c: SeqOps[A, Seq, Seq[A]]) extends AnyVal { + def isEmpty: false = false + def get: UnapplySeqWrapper[A] = this + def lengthCompare(len: Int): Int = c.lengthCompare(len) + def apply(i: Int): A = c(i) + def drop(n: Int): scala.Seq[A] = c match { + case seq: scala.Seq[A] => seq.drop(n) + case _ => c.view.drop(n).toSeq + } + def toSeq: scala.Seq[A] = c.toSeq + } +} + +trait StrictOptimizedSeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends SeqFactory[CC] { + + override def fill[A](n: Int)(elem: => A): CC[A] = { + val b = newBuilder[A] + b.sizeHint(n) + var i = 0 + while (i < n) { + b += elem + i += 1 + } + b.result() + } + + override def tabulate[A](n: Int)(f: Int => A): CC[A] = { + val b = newBuilder[A] + b.sizeHint(n) + var i = 0 + while (i < n) { + b += f(i) + i += 1 + } + b.result() + } + + override def concat[A](xss: Iterable[A]*): CC[A] = { + val b = newBuilder[A] + val knownSizes = xss.view.map(_.knownSize) + if (knownSizes forall (_ >= 0)) { + b.sizeHint(knownSizes.sum) + } + for (xs <- xss) b ++= xs + b.result() + } + +} + +/** + * @tparam A Type of elements (e.g. `Int`, `Boolean`, etc.) + * @tparam C Type of collection (e.g. `List[Int]`, `TreeMap[Int, String]`, etc.) + * @define factoryInfo + * This object provides a set of operations to create $Coll values. + * + * @define coll collection + * @define Coll `Iterable` + */ +trait SpecificIterableFactory[-A, +C] extends Factory[A, C] { + def empty: C + def apply(xs: A*): C = fromSpecific(xs) + def fill(n: Int)(elem: => A): C = fromSpecific(new View.Fill(n)(elem)) + def newBuilder: Builder[A, C] + + implicit def specificIterableFactory: Factory[A, C] = this +} + +/** + * @define factoryInfo + * This object provides a set of operations to create $Coll values. + * + * @define coll collection + * @define Coll `Iterable` + */ +trait MapFactory[+CC[_, _]] extends Serializable { + + /** + * An empty Map + */ + def empty[K, V]: CC[K, V] + + /** + * A collection of type Map generated from given iterable object. + */ + def from[K, V](it: IterableOnce[(K, V)]): CC[K, V] + + /** + * A collection of type Map that contains given key/value bindings. + */ + def apply[K, V](elems: (K, V)*): CC[K, V] = from(elems) + + /** + * The default builder for Map objects. + */ + def newBuilder[K, V]: Builder[(K, V), CC[K, V]] + + /** + * The default Factory instance for maps. + */ + implicit def mapFactory[K, V]: Factory[(K, V), CC[K, V]] = MapFactory.toFactory(this) +} + +object MapFactory { + + /** + * Fixes the key and value types of `factory` to `K` and `V`, respectively + * @param factory The factory to fix the key and value types + * @tparam K Type of keys + * @tparam V Type of values + * @tparam CC Collection type constructor of the factory (e.g. `Map`, `HashMap`, etc.) + * @return A [[Factory]] that uses the given `factory` to build a map with keys of type `K` + * and values of type `V` + */ + implicit def toFactory[K, V, CC[_, _]](factory: MapFactory[CC]): Factory[(K, V), CC[K, V]] = new ToFactory[K, V, CC](factory) + + @SerialVersionUID(3L) + private[this] class ToFactory[K, V, CC[_, _]](factory: MapFactory[CC]) extends Factory[(K, V), CC[K, V]] with Serializable { + def fromSpecific(it: IterableOnce[(K, V)]): CC[K, V] = factory.from[K, V](it) + def newBuilder: Builder[(K, V), CC[K, V]] = factory.newBuilder[K, V] + } + + implicit def toBuildFrom[K, V, CC[_, _]](factory: MapFactory[CC]): BuildFrom[Any, (K, V), CC[K, V]] = + new BuildFrom[Any, (K, V), CC[K, V]] { + def fromSpecific(from: Any)(it: IterableOnce[(K, V)]) = factory.from(it) + def newBuilder(from: Any) = factory.newBuilder[K, V] + } + + @SerialVersionUID(3L) + class Delegate[C[_, _]](delegate: MapFactory[C]) extends MapFactory[C] { + override def apply[K, V](elems: (K, V)*): C[K, V] = delegate.apply(elems: _*) + def from[K, V](it: IterableOnce[(K, V)]): C[K, V] = delegate.from(it) + def empty[K, V]: C[K, V] = delegate.empty + def newBuilder[K, V]: Builder[(K, V), C[K, V]] = delegate.newBuilder + } +} + +/** Base trait for companion objects of collections that require an implicit evidence. + * @tparam CC Collection type constructor (e.g. `ArraySeq`) + * @tparam Ev Unary type constructor for the implicit evidence required for an element type + * (typically `Ordering` or `ClassTag`) + * + * @define factoryInfo + * This object provides a set of operations to create $Coll values. + * + * @define coll collection + * @define Coll `Iterable` + */ +trait EvidenceIterableFactory[+CC[_], Ev[_]] extends Serializable { + + def from[E : Ev](it: IterableOnce[E]): CC[E] + + def empty[A : Ev]: CC[A] + + def apply[A : Ev](xs: A*): CC[A] = from(xs) + + /** Produces a $coll containing the results of some element computation a number of times. + * @param n the number of elements contained in the $coll. + * @param elem the element computation + * @return A $coll that contains the results of `n` evaluations of `elem`. + */ + def fill[A : Ev](n: Int)(elem: => A): CC[A] = from(new View.Fill(n)(elem)) + + /** Produces a $coll containing values of a given function over a range of integer values starting from 0. + * @param n The number of elements in the $coll + * @param f The function computing element values + * @return A $coll consisting of elements `f(0), ..., f(n -1)` + */ + def tabulate[A : Ev](n: Int)(f: Int => A): CC[A] = from(new View.Tabulate(n)(f)) + + /** Produces a $coll containing repeated applications of a function to a start value. + * + * @param start the start value of the $coll + * @param len the number of elements contained in the $coll + * @param f the function that's repeatedly applied + * @return a $coll with `len` values in the sequence `start, f(start), f(f(start)), ...` + */ + def iterate[A : Ev](start: A, len: Int)(f: A => A): CC[A] = from(new View.Iterate(start, len)(f)) + + /** Produces a $coll that uses a function `f` to produce elements of type `A` + * and update an internal state of type `S`. + * + * @param init State initial value + * @param f Computes the next element (or returns `None` to signal + * the end of the collection) + * @tparam A Type of the elements + * @tparam S Type of the internal state + * @return a $coll that produces elements using `f` until `f` returns `None` + */ + def unfold[A : Ev, S](init: S)(f: S => Option[(A, S)]): CC[A] = from(new View.Unfold(init)(f)) + + def newBuilder[A : Ev]: Builder[A, CC[A]] + + implicit def evidenceIterableFactory[A : Ev]: Factory[A, CC[A]] = EvidenceIterableFactory.toFactory(this) +} + +object EvidenceIterableFactory { + + /** + * Fixes the element type of `factory` to `A` + * @param factory The factory to fix the element type + * @tparam A Type of elements + * @tparam CC Collection type constructor of the factory (e.g. `TreeSet`) + * @tparam Ev Type constructor of the evidence (usually `Ordering` or `ClassTag`) + * @return A [[Factory]] that uses the given `factory` to build a collection of elements + * of type `A` + */ + implicit def toFactory[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]): Factory[A, CC[A]] = new ToFactory[Ev, A, CC](factory) + + @SerialVersionUID(3L) + private[this] class ToFactory[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]) extends Factory[A, CC[A]] with Serializable { + def fromSpecific(it: IterableOnce[A]): CC[A] = factory.from[A](it) + def newBuilder: Builder[A, CC[A]] = factory.newBuilder[A] + } + + implicit def toBuildFrom[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]): BuildFrom[Any, A, CC[A]] = new EvidenceIterableFactoryToBuildFrom(factory) + private class EvidenceIterableFactoryToBuildFrom[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]) extends BuildFrom[Any, A, CC[A]] { + def fromSpecific(from: Any)(it: IterableOnce[A]): CC[A] = factory.from[A](it) + def newBuilder(from: Any): Builder[A, CC[A]] = factory.newBuilder[A] + } + + @SerialVersionUID(3L) + class Delegate[CC[_], Ev[_]](delegate: EvidenceIterableFactory[CC, Ev]) extends EvidenceIterableFactory[CC, Ev] { + override def apply[A: Ev](xs: A*): CC[A] = delegate.apply(xs: _*) + def empty[A : Ev]: CC[A] = delegate.empty + def from[E : Ev](it: IterableOnce[E]): CC[E] = delegate.from(it) + def newBuilder[A : Ev]: Builder[A, CC[A]] = delegate.newBuilder[A] + } +} + +/** Base trait for companion objects of collections that require an implicit `Ordering`. + * @tparam CC Collection type constructor (e.g. `SortedSet`) + */ +trait SortedIterableFactory[+CC[_]] extends EvidenceIterableFactory[CC, Ordering] + +object SortedIterableFactory { + @SerialVersionUID(3L) + class Delegate[CC[_]](delegate: EvidenceIterableFactory[CC, Ordering]) + extends EvidenceIterableFactory.Delegate[CC, Ordering](delegate) with SortedIterableFactory[CC] +} + +/** Base trait for companion objects of collections that require an implicit `ClassTag`. + * @tparam CC Collection type constructor (e.g. `ArraySeq`) + */ +trait ClassTagIterableFactory[+CC[_]] extends EvidenceIterableFactory[CC, ClassTag] { + + @`inline` private[this] implicit def ccClassTag[X]: ClassTag[CC[X]] = + ClassTag.AnyRef.asInstanceOf[ClassTag[CC[X]]] // Good enough for boxed vs primitive arrays + + /** Produces a $coll containing a sequence of increasing of integers. + * + * @param start the first element of the $coll + * @param end the end value of the $coll (the first value NOT contained) + * @return a $coll with values `start, start + 1, ..., end - 1` + */ + def range[A : Integral : ClassTag](start: A, end: A): CC[A] = from(NumericRange(start, end, implicitly[Integral[A]].one)) + + /** Produces a $coll containing equally spaced values in some integer interval. + * @param start the start value of the $coll + * @param end the end value of the $coll (the first value NOT contained) + * @param step the difference between successive elements of the $coll (must be positive or negative) + * @return a $coll with values `start, start + step, ...` up to, but excluding `end` + */ + def range[A : Integral : ClassTag](start: A, end: A, step: A): CC[A] = from(NumericRange(start, end, step)) + + /** Produces a two-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2` evaluations of `elem`. + */ + def fill[A : ClassTag](n1: Int, n2: Int)(elem: => A): CC[CC[A] @uncheckedVariance] = fill(n1)(fill(n2)(elem)) + + /** Produces a three-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2 x n3` evaluations of `elem`. + */ + def fill[A : ClassTag](n1: Int, n2: Int, n3: Int)(elem: => A): CC[CC[CC[A]] @uncheckedVariance] = fill(n1)(fill(n2, n3)(elem)) + + /** Produces a four-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2 x n3 x n4` evaluations of `elem`. + */ + def fill[A : ClassTag](n1: Int, n2: Int, n3: Int, n4: Int)(elem: => A): CC[CC[CC[CC[A]]] @uncheckedVariance] = + fill(n1)(fill(n2, n3, n4)(elem)) + + /** Produces a five-dimensional $coll containing the results of some element computation a number of times. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param n5 the number of elements in the 5th dimension + * @param elem the element computation + * @return A $coll that contains the results of `n1 x n2 x n3 x n4 x n5` evaluations of `elem`. + */ + def fill[A : ClassTag](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(elem: => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance] = + fill(n1)(fill(n2, n3, n4, n5)(elem)) + + /** Produces a two-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2)` + * for `0 <= i1 < n1` and `0 <= i2 < n2`. + */ + def tabulate[A : ClassTag](n1: Int, n2: Int)(f: (Int, Int) => A): CC[CC[A] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2)(f(i1, _))) + + /** Produces a three-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2, i3)` + * for `0 <= i1 < n1`, `0 <= i2 < n2`, and `0 <= i3 < n3`. + */ + def tabulate[A : ClassTag](n1: Int, n2: Int, n3: Int)(f: (Int, Int, Int) => A): CC[CC[CC[A]] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2, n3)(f(i1, _, _))) + + /** Produces a four-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2, i3, i4)` + * for `0 <= i1 < n1`, `0 <= i2 < n2`, `0 <= i3 < n3`, and `0 <= i4 < n4`. + */ + def tabulate[A : ClassTag](n1: Int, n2: Int, n3: Int, n4: Int)(f: (Int, Int, Int, Int) => A): CC[CC[CC[CC[A]]] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2, n3, n4)(f(i1, _, _, _))) + + /** Produces a five-dimensional $coll containing values of a given function over ranges of integer values starting from 0. + * @param n1 the number of elements in the 1st dimension + * @param n2 the number of elements in the 2nd dimension + * @param n3 the number of elements in the 3rd dimension + * @param n4 the number of elements in the 4th dimension + * @param n5 the number of elements in the 5th dimension + * @param f The function computing element values + * @return A $coll consisting of elements `f(i1, i2, i3, i4, i5)` + * for `0 <= i1 < n1`, `0 <= i2 < n2`, `0 <= i3 < n3`, `0 <= i4 < n4`, and `0 <= i5 < n5`. + */ + def tabulate[A : ClassTag](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(f: (Int, Int, Int, Int, Int) => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance] = + tabulate(n1)(i1 => tabulate(n2, n3, n4, n5)(f(i1, _, _, _, _))) +} + +object ClassTagIterableFactory { + @SerialVersionUID(3L) + class Delegate[CC[_]](delegate: EvidenceIterableFactory[CC, ClassTag]) + extends EvidenceIterableFactory.Delegate[CC, ClassTag](delegate) with ClassTagIterableFactory[CC] + + /** An IterableFactory that uses ClassTag.Any as the evidence for every element type. This may or may not be + * sound depending on the use of the `ClassTag` by the collection implementation. */ + @SerialVersionUID(3L) + class AnyIterableDelegate[CC[_]](delegate: ClassTagIterableFactory[CC]) extends IterableFactory[CC] { + def empty[A]: CC[A] = delegate.empty(ClassTag.Any).asInstanceOf[CC[A]] + def from[A](it: IterableOnce[A]): CC[A] = delegate.from[Any](it)(ClassTag.Any).asInstanceOf[CC[A]] + def newBuilder[A]: Builder[A, CC[A]] = delegate.newBuilder(ClassTag.Any).asInstanceOf[Builder[A, CC[A]]] + override def apply[A](elems: A*): CC[A] = delegate.apply[Any](elems: _*)(ClassTag.Any).asInstanceOf[CC[A]] + override def iterate[A](start: A, len: Int)(f: A => A): CC[A] = delegate.iterate[A](start, len)(f)(ClassTag.Any.asInstanceOf[ClassTag[A]]) + override def unfold[A, S](init: S)(f: S => Option[(A, S)]): CC[A] = delegate.unfold[A, S](init)(f)(ClassTag.Any.asInstanceOf[ClassTag[A]]) + override def range[A](start: A, end: A)(implicit i: Integral[A]): CC[A] = delegate.range[A](start, end)(i, ClassTag.Any.asInstanceOf[ClassTag[A]]) + override def range[A](start: A, end: A, step: A)(implicit i: Integral[A]): CC[A] = delegate.range[A](start, end, step)(i, ClassTag.Any.asInstanceOf[ClassTag[A]]) + override def fill[A](n: Int)(elem: => A): CC[A] = delegate.fill[Any](n)(elem)(ClassTag.Any).asInstanceOf[CC[A]] + override def tabulate[A](n: Int)(f: Int => A): CC[A] = delegate.tabulate[Any](n)(f)(ClassTag.Any).asInstanceOf[CC[A]] + } +} + +/** + * @tparam CC Collection type constructor (e.g. `ArraySeq`) + */ +trait ClassTagSeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends ClassTagIterableFactory[CC] { + import SeqFactory.UnapplySeqWrapper + final def unapplySeq[A](x: CC[A] @uncheckedVariance): UnapplySeqWrapper[A] = new UnapplySeqWrapper(x) // TODO is uncheckedVariance sound here? +} + +object ClassTagSeqFactory { + @SerialVersionUID(3L) + class Delegate[CC[A] <: SeqOps[A, Seq, Seq[A]]](delegate: ClassTagSeqFactory[CC]) + extends ClassTagIterableFactory.Delegate[CC](delegate) with ClassTagSeqFactory[CC] + + /** A SeqFactory that uses ClassTag.Any as the evidence for every element type. This may or may not be + * sound depending on the use of the `ClassTag` by the collection implementation. */ + @SerialVersionUID(3L) + class AnySeqDelegate[CC[A] <: SeqOps[A, Seq, Seq[A]]](delegate: ClassTagSeqFactory[CC]) + extends ClassTagIterableFactory.AnyIterableDelegate[CC](delegate) with SeqFactory[CC] +} + +trait StrictOptimizedClassTagSeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends ClassTagSeqFactory[CC] { + + override def fill[A : ClassTag](n: Int)(elem: => A): CC[A] = { + val b = newBuilder[A] + b.sizeHint(n) + var i = 0 + while (i < n) { + b += elem + i += 1 + } + b.result() + } + + override def tabulate[A : ClassTag](n: Int)(f: Int => A): CC[A] = { + val b = newBuilder[A] + b.sizeHint(n) + var i = 0 + while (i < n) { + b += f(i) + i += 1 + } + b.result() + } + +} + +/** + * @define factoryInfo + * This object provides a set of operations to create $Coll values. + * + * @define coll collection + * @define Coll `Iterable` + */ +trait SortedMapFactory[+CC[_, _]] extends Serializable { + + def empty[K : Ordering, V]: CC[K, V] + + def from[K : Ordering, V](it: IterableOnce[(K, V)]): CC[K, V] + + def apply[K : Ordering, V](elems: (K, V)*): CC[K, V] = from(elems) + + def newBuilder[K : Ordering, V]: Builder[(K, V), CC[K, V]] + + implicit def sortedMapFactory[K : Ordering, V]: Factory[(K, V), CC[K, V]] = SortedMapFactory.toFactory(this) + +} + +object SortedMapFactory { + + /** + * Implicit conversion that fixes the key and value types of `factory` to `K` and `V`, + * respectively. + * + * @param factory The factory to fix the key and value types + * @tparam K Type of keys + * @tparam V Type of values + * @tparam CC Collection type constructor of the factory (e.g. `TreeMap`) + * @return A [[Factory]] that uses the given `factory` to build a map with keys of + * type `K` and values of type `V` + */ + implicit def toFactory[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]): Factory[(K, V), CC[K, V]] = new ToFactory[K, V, CC](factory) + + @SerialVersionUID(3L) + private[this] class ToFactory[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]) extends Factory[(K, V), CC[K, V]] with Serializable { + def fromSpecific(it: IterableOnce[(K, V)]): CC[K, V] = factory.from[K, V](it) + def newBuilder: Builder[(K, V), CC[K, V]] = factory.newBuilder[K, V] + } + + implicit def toBuildFrom[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]): BuildFrom[Any, (K, V), CC[K, V]] = new SortedMapFactoryToBuildFrom(factory) + private class SortedMapFactoryToBuildFrom[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]) extends BuildFrom[Any, (K, V), CC[K, V]] { + def fromSpecific(from: Any)(it: IterableOnce[(K, V)]) = factory.from(it) + def newBuilder(from: Any) = factory.newBuilder[K, V] + } + + @SerialVersionUID(3L) + class Delegate[CC[_, _]](delegate: SortedMapFactory[CC]) extends SortedMapFactory[CC] { + override def apply[K: Ordering, V](elems: (K, V)*): CC[K, V] = delegate.apply(elems: _*) + def from[K : Ordering, V](it: IterableOnce[(K, V)]): CC[K, V] = delegate.from(it) + def empty[K : Ordering, V]: CC[K, V] = delegate.empty + def newBuilder[K : Ordering, V]: Builder[(K, V), CC[K, V]] = delegate.newBuilder + } +} From 5852a76053d6657e9770aaf163e5de92b7399823 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 22:53:38 +0100 Subject: [PATCH 31/89] Make Factory capture checked --- .../stdlib/collection/Factory.scala | 101 ++++++++++-------- .../stdlib/collection/Iterable.scala | 6 +- tests/pos-special/stdlib/collection/Seq.scala | 2 + .../collection/immutable/Iterable.scala | 2 +- .../collection/mutable/ArrayDeque.scala | 2 +- .../stdlib/collection/mutable/ArraySeq.scala | 2 +- .../stdlib/collection/mutable/Queue.scala | 2 +- .../stdlib/collection/mutable/Stack.scala | 2 +- 8 files changed, 67 insertions(+), 52 deletions(-) diff --git a/tests/pos-special/stdlib/collection/Factory.scala b/tests/pos-special/stdlib/collection/Factory.scala index 2b15f1cc15d1..9979ef1bd619 100644 --- a/tests/pos-special/stdlib/collection/Factory.scala +++ b/tests/pos-special/stdlib/collection/Factory.scala @@ -18,6 +18,8 @@ import scala.language.implicitConversions import scala.collection.mutable.Builder import scala.annotation.unchecked.uncheckedVariance import scala.reflect.ClassTag +import language.experimental.captureChecking +import caps.unsafe.unsafeAssumePure /** * A factory that builds a collection of type `C` with elements of type `A`. @@ -29,14 +31,14 @@ import scala.reflect.ClassTag * @tparam A Type of elements (e.g. `Int`, `Boolean`, etc.) * @tparam C Type of collection (e.g. `List[Int]`, `TreeMap[Int, String]`, etc.) */ -trait Factory[-A, +C] extends Any { +trait Factory[-A, +C] extends Pure { /** * @return A collection of type `C` containing the same elements * as the source collection `it`. * @param it Source collection */ - def fromSpecific(it: IterableOnce[A]): C + def fromSpecific(it: IterableOnce[A]^): C /** Get a Builder for the collection. For non-strict collection types this will use an intermediate buffer. * Building collections with `fromSpecific` is preferred because it can be lazy for lazy collections. */ @@ -48,7 +50,7 @@ object Factory { implicit val stringFactory: Factory[Char, String] = new StringFactory @SerialVersionUID(3L) private class StringFactory extends Factory[Char, String] with Serializable { - def fromSpecific(it: IterableOnce[Char]): String = { + def fromSpecific(it: IterableOnce[Char]^): String = { val b = new mutable.StringBuilder(scala.math.max(0, it.knownSize)) b ++= it b.result() @@ -56,10 +58,10 @@ object Factory { def newBuilder: Builder[Char, String] = new mutable.StringBuilder() } - implicit def arrayFactory[A: ClassTag]: Factory[A, Array[A]] = new ArrayFactory[A] + implicit def arrayFactory[sealed A: ClassTag]: Factory[A, Array[A]] = new ArrayFactory[A] @SerialVersionUID(3L) - private class ArrayFactory[A: ClassTag] extends Factory[A, Array[A]] with Serializable { - def fromSpecific(it: IterableOnce[A]): Array[A] = { + private class ArrayFactory[sealed A: ClassTag] extends Factory[A, Array[A]] with Serializable { + def fromSpecific(it: IterableOnce[A]^): Array[A] = { val b = newBuilder b.sizeHint(scala.math.max(0, it.knownSize)) b ++= it @@ -80,7 +82,7 @@ object Factory { * @define coll collection * @define Coll `Iterable` */ -trait IterableFactory[+CC[_]] extends Serializable { +trait IterableFactory[+CC[_]] extends Serializable, Pure { /** Creates a target $coll from an existing source collection * @@ -88,7 +90,7 @@ trait IterableFactory[+CC[_]] extends Serializable { * @tparam A the type of the collection’s elements * @return a new $coll with the elements of `source` */ - def from[A](source: IterableOnce[A]): CC[A] + def from[A](source: IterableOnce[A]^): CC[A]^{source} /** An empty collection * @tparam A the type of the ${coll}'s elements @@ -109,7 +111,7 @@ trait IterableFactory[+CC[_]] extends Serializable { * @param f the function that's repeatedly applied * @return a $coll with `len` values in the sequence `start, f(start), f(f(start)), ...` */ - def iterate[A](start: A, len: Int)(f: A => A): CC[A] = from(new View.Iterate(start, len)(f)) + def iterate[A](start: A, len: Int)(f: A => A): CC[A]^{f} = from(new View.Iterate(start, len)(f)) /** Produces a $coll that uses a function `f` to produce elements of type `A` * and update an internal state of type `S`. @@ -121,7 +123,7 @@ trait IterableFactory[+CC[_]] extends Serializable { * @tparam S Type of the internal state * @return a $coll that produces elements using `f` until `f` returns `None` */ - def unfold[A, S](init: S)(f: S => Option[(A, S)]): CC[A] = from(new View.Unfold(init)(f)) + def unfold[A, S](init: S)(f: S => Option[(A, S)]): CC[A]^{f} = from(new View.Unfold(init)(f)) /** Produces a $coll containing a sequence of increasing of integers. * @@ -150,7 +152,7 @@ trait IterableFactory[+CC[_]] extends Serializable { * @param elem the element computation * @return A $coll that contains the results of `n` evaluations of `elem`. */ - def fill[A](n: Int)(elem: => A): CC[A] = from(new View.Fill(n)(elem)) + def fill[A](n: Int)(elem: => A): CC[A]^{elem} = from(new View.Fill(n)(elem)) /** Produces a two-dimensional $coll containing the results of some element computation a number of times. * @param n1 the number of elements in the 1st dimension @@ -158,7 +160,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @param elem the element computation * @return A $coll that contains the results of `n1 x n2` evaluations of `elem`. */ - def fill[A](n1: Int, n2: Int)(elem: => A): CC[CC[A] @uncheckedVariance] = fill(n1)(fill(n2)(elem)) + def fill[A](n1: Int, n2: Int)(elem: => A): CC[CC[A] @uncheckedVariance]^{elem} = // !!! problem with checking rhs under cc + ??? // fill(n1)(fill(n2)(elem)) /** Produces a three-dimensional $coll containing the results of some element computation a number of times. * @param n1 the number of elements in the 1st dimension @@ -167,7 +170,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @param elem the element computation * @return A $coll that contains the results of `n1 x n2 x n3` evaluations of `elem`. */ - def fill[A](n1: Int, n2: Int, n3: Int)(elem: => A): CC[CC[CC[A]] @uncheckedVariance] = fill(n1)(fill(n2, n3)(elem)) + def fill[A](n1: Int, n2: Int, n3: Int)(elem: => A): CC[CC[CC[A]] @uncheckedVariance]^{elem} = // !!! problem with checking rhs under cc + ??? // fill(n1)(fill(n2, n3)(elem)).unsafeAssumePure /** Produces a four-dimensional $coll containing the results of some element computation a number of times. * @param n1 the number of elements in the 1st dimension @@ -177,8 +181,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @param elem the element computation * @return A $coll that contains the results of `n1 x n2 x n3 x n4` evaluations of `elem`. */ - def fill[A](n1: Int, n2: Int, n3: Int, n4: Int)(elem: => A): CC[CC[CC[CC[A]]] @uncheckedVariance] = - fill(n1)(fill(n2, n3, n4)(elem)) + def fill[A](n1: Int, n2: Int, n3: Int, n4: Int)(elem: => A): CC[CC[CC[CC[A]]] @uncheckedVariance]^{elem} = // !!! problem with checking rhs under cc + ??? // fill(n1)(fill(n2, n3, n4)(elem)) /** Produces a five-dimensional $coll containing the results of some element computation a number of times. * @param n1 the number of elements in the 1st dimension @@ -189,15 +193,15 @@ trait IterableFactory[+CC[_]] extends Serializable { * @param elem the element computation * @return A $coll that contains the results of `n1 x n2 x n3 x n4 x n5` evaluations of `elem`. */ - def fill[A](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(elem: => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance] = - fill(n1)(fill(n2, n3, n4, n5)(elem)) + def fill[A](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(elem: => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance]^{elem} = // !!! problem with checking rhs under cc + ??? // fill(n1)(fill(n2, n3, n4, n5)(elem)) /** Produces a $coll containing values of a given function over a range of integer values starting from 0. * @param n The number of elements in the $coll * @param f The function computing element values * @return A $coll consisting of elements `f(0), ..., f(n -1)` */ - def tabulate[A](n: Int)(f: Int => A): CC[A] = from(new View.Tabulate(n)(f)) + def tabulate[A](n: Int)(f: Int => A): CC[A]^{f} = from(new View.Tabulate(n)(f)) /** Produces a two-dimensional $coll containing values of a given function over ranges of integer values starting from 0. * @param n1 the number of elements in the 1st dimension @@ -206,8 +210,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @return A $coll consisting of elements `f(i1, i2)` * for `0 <= i1 < n1` and `0 <= i2 < n2`. */ - def tabulate[A](n1: Int, n2: Int)(f: (Int, Int) => A): CC[CC[A] @uncheckedVariance] = - tabulate(n1)(i1 => tabulate(n2)(f(i1, _))) + def tabulate[A](n1: Int, n2: Int)(f: (Int, Int) => A): CC[CC[A] @uncheckedVariance]^{f} = // !!! problem with checking rhs under cc + ??? // tabulate(n1)(i1 => tabulate(n2)(f(i1, _))) /** Produces a three-dimensional $coll containing values of a given function over ranges of integer values starting from 0. * @param n1 the number of elements in the 1st dimension @@ -217,8 +221,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @return A $coll consisting of elements `f(i1, i2, i3)` * for `0 <= i1 < n1`, `0 <= i2 < n2`, and `0 <= i3 < n3`. */ - def tabulate[A](n1: Int, n2: Int, n3: Int)(f: (Int, Int, Int) => A): CC[CC[CC[A]] @uncheckedVariance] = - tabulate(n1)(i1 => tabulate(n2, n3)(f(i1, _, _))) + def tabulate[A](n1: Int, n2: Int, n3: Int)(f: (Int, Int, Int) => A): CC[CC[CC[A]] @uncheckedVariance]^{f} = // !!! problem with checking rhs under cc + ??? // tabulate(n1)(i1 => tabulate(n2, n3)(f(i1, _, _))) /** Produces a four-dimensional $coll containing values of a given function over ranges of integer values starting from 0. * @param n1 the number of elements in the 1st dimension @@ -229,8 +233,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @return A $coll consisting of elements `f(i1, i2, i3, i4)` * for `0 <= i1 < n1`, `0 <= i2 < n2`, `0 <= i3 < n3`, and `0 <= i4 < n4`. */ - def tabulate[A](n1: Int, n2: Int, n3: Int, n4: Int)(f: (Int, Int, Int, Int) => A): CC[CC[CC[CC[A]]] @uncheckedVariance] = - tabulate(n1)(i1 => tabulate(n2, n3, n4)(f(i1, _, _, _))) + def tabulate[A](n1: Int, n2: Int, n3: Int, n4: Int)(f: (Int, Int, Int, Int) => A): CC[CC[CC[CC[A]]] @uncheckedVariance]^{f} = // !!! problem with checking rhs under cc + ??? // tabulate(n1)(i1 => tabulate(n2, n3, n4)(f(i1, _, _, _))) /** Produces a five-dimensional $coll containing values of a given function over ranges of integer values starting from 0. * @param n1 the number of elements in the 1st dimension @@ -242,8 +246,8 @@ trait IterableFactory[+CC[_]] extends Serializable { * @return A $coll consisting of elements `f(i1, i2, i3, i4, i5)` * for `0 <= i1 < n1`, `0 <= i2 < n2`, `0 <= i3 < n3`, `0 <= i4 < n4`, and `0 <= i5 < n5`. */ - def tabulate[A](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(f: (Int, Int, Int, Int, Int) => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance] = - tabulate(n1)(i1 => tabulate(n2, n3, n4, n5)(f(i1, _, _, _, _))) + def tabulate[A](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(f: (Int, Int, Int, Int, Int) => A): CC[CC[CC[CC[CC[A]]]] @uncheckedVariance]^{f} = // !!! problem with checking rhs under cc + ??? // tabulate(n1)(i1 => tabulate(n2, n3, n4, n5)(f(i1, _, _, _, _))) /** Concatenates all argument collections into a single $coll. * @@ -271,13 +275,14 @@ object IterableFactory { @SerialVersionUID(3L) private[this] class ToFactory[A, CC[_]](factory: IterableFactory[CC]) extends Factory[A, CC[A]] with Serializable { - def fromSpecific(it: IterableOnce[A]): CC[A] = factory.from[A](it) + def fromSpecific(it: IterableOnce[A]^): CC[A] = factory.from[A](it).unsafeAssumePure + // unsafeAssumePure needed but is unsound, since we confuse Seq and Iterable fromSpecific def newBuilder: Builder[A, CC[A]] = factory.newBuilder[A] } implicit def toBuildFrom[A, CC[_]](factory: IterableFactory[CC]): BuildFrom[Any, A, CC[A]] = new BuildFrom[Any, A, CC[A]] { - def fromSpecific(from: Any)(it: IterableOnce[A]) = factory.from(it) + def fromSpecific(from: Any)(it: IterableOnce[A]^): CC[A]^{it} = factory.from(it) def newBuilder(from: Any) = factory.newBuilder } @@ -285,15 +290,20 @@ object IterableFactory { class Delegate[CC[_]](delegate: IterableFactory[CC]) extends IterableFactory[CC] { override def apply[A](elems: A*): CC[A] = delegate.apply(elems: _*) def empty[A]: CC[A] = delegate.empty - def from[E](it: IterableOnce[E]): CC[E] = delegate.from(it) + def from[E](it: IterableOnce[E]^): CC[E]^{it} = delegate.from(it) def newBuilder[A]: Builder[A, CC[A]] = delegate.newBuilder[A] } } +// !!! Needed to add this separate trait +trait FreeSeqFactory[+CC[A]] extends IterableFactory[CC]: + def from[A](source: IterableOnce[A]^): CC[A] + override def apply[A](elems: A*): CC[A] = from(elems) + /** * @tparam CC Collection type constructor (e.g. `List`) */ -trait SeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends IterableFactory[CC] { +trait SeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends FreeSeqFactory[CC] { import SeqFactory.UnapplySeqWrapper final def unapplySeq[A](x: CC[A] @uncheckedVariance): UnapplySeqWrapper[A] = new UnapplySeqWrapper(x) // TODO is uncheckedVariance sound here? } @@ -303,7 +313,7 @@ object SeqFactory { class Delegate[CC[A] <: SeqOps[A, Seq, Seq[A]]](delegate: SeqFactory[CC]) extends SeqFactory[CC] { override def apply[A](elems: A*): CC[A] = delegate.apply(elems: _*) def empty[A]: CC[A] = delegate.empty - def from[E](it: IterableOnce[E]): CC[E] = delegate.from(it) + def from[E](it: IterableOnce[E]^): CC[E] = delegate.from(it) def newBuilder[A]: Builder[A, CC[A]] = delegate.newBuilder[A] } @@ -366,6 +376,8 @@ trait StrictOptimizedSeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extends SeqFac * @define Coll `Iterable` */ trait SpecificIterableFactory[-A, +C] extends Factory[A, C] { + this: SpecificIterableFactory[A, C] => + def empty: C def apply(xs: A*): C = fromSpecific(xs) def fill(n: Int)(elem: => A): C = fromSpecific(new View.Fill(n)(elem)) @@ -381,7 +393,7 @@ trait SpecificIterableFactory[-A, +C] extends Factory[A, C] { * @define coll collection * @define Coll `Iterable` */ -trait MapFactory[+CC[_, _]] extends Serializable { +trait MapFactory[+CC[_, _]] extends Serializable, Pure { /** * An empty Map @@ -391,7 +403,7 @@ trait MapFactory[+CC[_, _]] extends Serializable { /** * A collection of type Map generated from given iterable object. */ - def from[K, V](it: IterableOnce[(K, V)]): CC[K, V] + def from[K, V](it: IterableOnce[(K, V)]^): CC[K, V] /** * A collection of type Map that contains given key/value bindings. @@ -424,20 +436,20 @@ object MapFactory { @SerialVersionUID(3L) private[this] class ToFactory[K, V, CC[_, _]](factory: MapFactory[CC]) extends Factory[(K, V), CC[K, V]] with Serializable { - def fromSpecific(it: IterableOnce[(K, V)]): CC[K, V] = factory.from[K, V](it) + def fromSpecific(it: IterableOnce[(K, V)]^): CC[K, V] = factory.from[K, V](it) def newBuilder: Builder[(K, V), CC[K, V]] = factory.newBuilder[K, V] } implicit def toBuildFrom[K, V, CC[_, _]](factory: MapFactory[CC]): BuildFrom[Any, (K, V), CC[K, V]] = new BuildFrom[Any, (K, V), CC[K, V]] { - def fromSpecific(from: Any)(it: IterableOnce[(K, V)]) = factory.from(it) + def fromSpecific(from: Any)(it: IterableOnce[(K, V)]^) = factory.from(it) def newBuilder(from: Any) = factory.newBuilder[K, V] } @SerialVersionUID(3L) class Delegate[C[_, _]](delegate: MapFactory[C]) extends MapFactory[C] { override def apply[K, V](elems: (K, V)*): C[K, V] = delegate.apply(elems: _*) - def from[K, V](it: IterableOnce[(K, V)]): C[K, V] = delegate.from(it) + def from[K, V](it: IterableOnce[(K, V)]^): C[K, V] = delegate.from(it) def empty[K, V]: C[K, V] = delegate.empty def newBuilder[K, V]: Builder[(K, V), C[K, V]] = delegate.newBuilder } @@ -454,9 +466,9 @@ object MapFactory { * @define coll collection * @define Coll `Iterable` */ -trait EvidenceIterableFactory[+CC[_], Ev[_]] extends Serializable { +trait EvidenceIterableFactory[+CC[_], Ev[_]] extends Serializable, Pure { - def from[E : Ev](it: IterableOnce[E]): CC[E] + def from[E : Ev](it: IterableOnce[E]^): CC[E] def empty[A : Ev]: CC[A] @@ -517,7 +529,7 @@ object EvidenceIterableFactory { @SerialVersionUID(3L) private[this] class ToFactory[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]) extends Factory[A, CC[A]] with Serializable { - def fromSpecific(it: IterableOnce[A]): CC[A] = factory.from[A](it) + def fromSpecific(it: IterableOnce[A]^): CC[A] = factory.from[A](it) def newBuilder: Builder[A, CC[A]] = factory.newBuilder[A] } @@ -531,7 +543,7 @@ object EvidenceIterableFactory { class Delegate[CC[_], Ev[_]](delegate: EvidenceIterableFactory[CC, Ev]) extends EvidenceIterableFactory[CC, Ev] { override def apply[A: Ev](xs: A*): CC[A] = delegate.apply(xs: _*) def empty[A : Ev]: CC[A] = delegate.empty - def from[E : Ev](it: IterableOnce[E]): CC[E] = delegate.from(it) + def from[E : Ev](it: IterableOnce[E]^): CC[E] = delegate.from(it) def newBuilder[A : Ev]: Builder[A, CC[A]] = delegate.newBuilder[A] } } @@ -668,7 +680,7 @@ object ClassTagIterableFactory { @SerialVersionUID(3L) class AnyIterableDelegate[CC[_]](delegate: ClassTagIterableFactory[CC]) extends IterableFactory[CC] { def empty[A]: CC[A] = delegate.empty(ClassTag.Any).asInstanceOf[CC[A]] - def from[A](it: IterableOnce[A]): CC[A] = delegate.from[Any](it)(ClassTag.Any).asInstanceOf[CC[A]] + def from[A](it: IterableOnce[A]^): CC[A] = delegate.from[Any](it)(ClassTag.Any).asInstanceOf[CC[A]] def newBuilder[A]: Builder[A, CC[A]] = delegate.newBuilder(ClassTag.Any).asInstanceOf[Builder[A, CC[A]]] override def apply[A](elems: A*): CC[A] = delegate.apply[Any](elems: _*)(ClassTag.Any).asInstanceOf[CC[A]] override def iterate[A](start: A, len: Int)(f: A => A): CC[A] = delegate.iterate[A](start, len)(f)(ClassTag.Any.asInstanceOf[ClassTag[A]]) @@ -734,10 +746,11 @@ trait StrictOptimizedClassTagSeqFactory[+CC[A] <: SeqOps[A, Seq, Seq[A]]] extend * @define Coll `Iterable` */ trait SortedMapFactory[+CC[_, _]] extends Serializable { + this: SortedMapFactory[CC] => def empty[K : Ordering, V]: CC[K, V] - def from[K : Ordering, V](it: IterableOnce[(K, V)]): CC[K, V] + def from[K : Ordering, V](it: IterableOnce[(K, V)]^): CC[K, V] def apply[K : Ordering, V](elems: (K, V)*): CC[K, V] = from(elems) @@ -764,7 +777,7 @@ object SortedMapFactory { @SerialVersionUID(3L) private[this] class ToFactory[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]) extends Factory[(K, V), CC[K, V]] with Serializable { - def fromSpecific(it: IterableOnce[(K, V)]): CC[K, V] = factory.from[K, V](it) + def fromSpecific(it: IterableOnce[(K, V)]^): CC[K, V] = factory.from[K, V](it) def newBuilder: Builder[(K, V), CC[K, V]] = factory.newBuilder[K, V] } @@ -777,7 +790,7 @@ object SortedMapFactory { @SerialVersionUID(3L) class Delegate[CC[_, _]](delegate: SortedMapFactory[CC]) extends SortedMapFactory[CC] { override def apply[K: Ordering, V](elems: (K, V)*): CC[K, V] = delegate.apply(elems: _*) - def from[K : Ordering, V](it: IterableOnce[(K, V)]): CC[K, V] = delegate.from(it) + def from[K : Ordering, V](it: IterableOnce[(K, V)]^): CC[K, V] = delegate.from(it) def empty[K : Ordering, V]: CC[K, V] = delegate.empty def newBuilder[K : Ordering, V]: Builder[(K, V), CC[K, V]] = delegate.newBuilder } diff --git a/tests/pos-special/stdlib/collection/Iterable.scala b/tests/pos-special/stdlib/collection/Iterable.scala index 85c0debc6685..7b5eb39314d3 100644 --- a/tests/pos-special/stdlib/collection/Iterable.scala +++ b/tests/pos-special/stdlib/collection/Iterable.scala @@ -400,7 +400,7 @@ trait IterableOps[+A, +CC[_], +C] extends Any with IterableOnce[A] with Iterable if (i != headSize) fail } - iterableFactory.from(bs.map(_.result())) + iterableFactory.from(bs.map(_.result())).asInstanceOf // !!! needed for cc } def filter(pred: A => Boolean): C^{this, pred} = fromSpecific(new View.Filter(this, pred, isFlipped = false)) @@ -902,10 +902,10 @@ object IterableOps { protected def filtered: Iterable[A]^{this} = new View.Filter(self, p, isFlipped = false) - def map[B](f: A => B): CC[B]^{this} = + def map[B](f: A => B): CC[B]^{this, f} = self.iterableFactory.from(new View.Map(filtered, f)) - def flatMap[B](f: A => IterableOnce[B]): CC[B]^{this} = + def flatMap[B](f: A => IterableOnce[B]): CC[B]^{this, f} = self.iterableFactory.from(new View.FlatMap(filtered, f)) def foreach[U](f: A => U): Unit = filtered.foreach(f) diff --git a/tests/pos-special/stdlib/collection/Seq.scala b/tests/pos-special/stdlib/collection/Seq.scala index 05b315c49a8c..3a30906b467c 100644 --- a/tests/pos-special/stdlib/collection/Seq.scala +++ b/tests/pos-special/stdlib/collection/Seq.scala @@ -82,6 +82,8 @@ trait SeqOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { self => override def view: SeqView[A] = new SeqView.Id[A](this) + def iterableFactory: FreeSeqFactory[CC] + /** Get the element at the specified index. This operation is provided for convenience in `Seq`. It should * not be assumed to be efficient unless you have an `IndexedSeq`. */ @throws[IndexOutOfBoundsException] diff --git a/tests/pos-special/stdlib/collection/immutable/Iterable.scala b/tests/pos-special/stdlib/collection/immutable/Iterable.scala index 44f13d0f2895..c4f9900eea8b 100644 --- a/tests/pos-special/stdlib/collection/immutable/Iterable.scala +++ b/tests/pos-special/stdlib/collection/immutable/Iterable.scala @@ -32,7 +32,7 @@ trait Iterable[+A] extends collection.Iterable[A] @SerialVersionUID(3L) object Iterable extends IterableFactory.Delegate[Iterable](List) { - override def from[E](it: IterableOnce[E]): Iterable[E] = it match { + override def from[E](it: IterableOnce[E]^): Iterable[E]^{it} = it match { case iterable: Iterable[E] => iterable case _ => super.from(it) } diff --git a/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala b/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala index 8c6b059cd8a6..f22aacec65c5 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArrayDeque.scala @@ -526,7 +526,7 @@ class ArrayDeque[sealed A] protected ( @SerialVersionUID(3L) object ArrayDeque extends StrictOptimizedSeqFactory[ArrayDeque] { - def from[sealed B](coll: collection.IterableOnce[B]): ArrayDeque[B] = { + def from[sealed B](coll: collection.IterableOnce[B]^): ArrayDeque[B] = { val s = coll.knownSize if (s >= 0) { val array = alloc(s) diff --git a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala index 9bdb28517eff..1c41f68bc8bb 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala @@ -110,7 +110,7 @@ object ArraySeq extends StrictOptimizedClassTagSeqFactory[ArraySeq] { self => private[this] val EmptyArraySeq = new ofRef[AnyRef](new Array[AnyRef](0)) def empty[T : ClassTag]: ArraySeq[T] = EmptyArraySeq.asInstanceOf[ArraySeq[T]] - def from[sealed A : ClassTag](it: scala.collection.IterableOnce[A]): ArraySeq[A] = make(Array.from[A](it)) + def from[sealed A : ClassTag](it: scala.collection.IterableOnce[A]^): ArraySeq[A] = make(Array.from[A](it)) def newBuilder[sealed A : ClassTag]: Builder[A, ArraySeq[A]] = ArrayBuilder.make[A].mapResult(make) diff --git a/tests/pos-special/stdlib/collection/mutable/Queue.scala b/tests/pos-special/stdlib/collection/mutable/Queue.scala index 8c0b5cea1133..a578b0742009 100644 --- a/tests/pos-special/stdlib/collection/mutable/Queue.scala +++ b/tests/pos-special/stdlib/collection/mutable/Queue.scala @@ -130,7 +130,7 @@ class Queue[sealed A] protected (array: Array[AnyRef], start: Int, end: Int) @SerialVersionUID(3L) object Queue extends StrictOptimizedSeqFactory[Queue] { - def from[sealed A](source: IterableOnce[A]): Queue[A] = empty ++= source + def from[sealed A](source: IterableOnce[A]^): Queue[A] = empty ++= source def empty[sealed A]: Queue[A] = new Queue diff --git a/tests/pos-special/stdlib/collection/mutable/Stack.scala b/tests/pos-special/stdlib/collection/mutable/Stack.scala index d39afe4d099e..4efa9621f374 100644 --- a/tests/pos-special/stdlib/collection/mutable/Stack.scala +++ b/tests/pos-special/stdlib/collection/mutable/Stack.scala @@ -135,7 +135,7 @@ class Stack[sealed A] protected (array: Array[AnyRef], start: Int, end: Int) @SerialVersionUID(3L) object Stack extends StrictOptimizedSeqFactory[Stack] { - def from[sealed A](source: IterableOnce[A]): Stack[A] = empty ++= source + def from[sealed A](source: IterableOnce[A]^): Stack[A] = empty ++= source def empty[sealed A]: Stack[A] = new Stack From c9cb0449eddf63c500a88340709f4111875d2d59 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 22:54:28 +0100 Subject: [PATCH 32/89] Avoid reporting post check messages several times --- compiler/src/dotty/tools/dotc/cc/Setup.scala | 1 + .../tools/dotc/reporting/UniqueMessagePositions.scala | 10 +++++----- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/compiler/src/dotty/tools/dotc/cc/Setup.scala b/compiler/src/dotty/tools/dotc/cc/Setup.scala index e90a8394f87d..8ba53693870c 100644 --- a/compiler/src/dotty/tools/dotc/cc/Setup.scala +++ b/compiler/src/dotty/tools/dotc/cc/Setup.scala @@ -707,4 +707,5 @@ class Setup extends PreRecheck, SymTransformer, SetupAPI: def postCheck()(using Context): Unit = for chk <- todoAtPostCheck do chk(ctx) + todoAtPostCheck.clear() end Setup \ No newline at end of file diff --git a/compiler/src/dotty/tools/dotc/reporting/UniqueMessagePositions.scala b/compiler/src/dotty/tools/dotc/reporting/UniqueMessagePositions.scala index 98fd7da3032a..71b2636ab8ed 100644 --- a/compiler/src/dotty/tools/dotc/reporting/UniqueMessagePositions.scala +++ b/compiler/src/dotty/tools/dotc/reporting/UniqueMessagePositions.scala @@ -25,14 +25,14 @@ trait UniqueMessagePositions extends Reporter { || dia.pos.exists && !ctx.settings.YshowSuppressedErrors.value - && (dia.pos.start to dia.pos.end).exists(pos => - positions.get((ctx.source, pos)).exists(_.hides(dia))) + && (dia.pos.start to dia.pos.end).exists: offset => + positions.get((ctx.source, offset)).exists(_.hides(dia)) override def markReported(dia: Diagnostic)(using Context): Unit = if dia.pos.exists then - for (pos <- dia.pos.start to dia.pos.end) - positions.get(ctx.source, pos) match + for offset <- dia.pos.start to dia.pos.end do + positions.get((ctx.source, offset)) match case Some(dia1) if dia1.hides(dia) => - case _ => positions((ctx.source, pos)) = dia + case _ => positions((ctx.source, offset)) = dia super.markReported(dia) } From 0a350ea88bd317079f472fb00d222bb756d6c15a Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 22:54:51 +0100 Subject: [PATCH 33/89] Add SortedSet and BitSet to stdlib (capture checked) --- tests/pos-special/stdlib/collection/BitSet.scala | 2 +- tests/pos-special/stdlib/collection/SortedSet.scala | 5 +++-- tests/pos-special/stdlib/collection/immutable/BitSet.scala | 2 +- .../pos-special/stdlib/collection/immutable/SortedSet.scala | 3 ++- tests/pos-special/stdlib/collection/mutable/BitSet.scala | 2 +- tests/pos-special/stdlib/collection/mutable/SortedSet.scala | 1 + 6 files changed, 9 insertions(+), 6 deletions(-) diff --git a/tests/pos-special/stdlib/collection/BitSet.scala b/tests/pos-special/stdlib/collection/BitSet.scala index 62326dfd2152..39c15dbe808f 100644 --- a/tests/pos-special/stdlib/collection/BitSet.scala +++ b/tests/pos-special/stdlib/collection/BitSet.scala @@ -48,7 +48,7 @@ object BitSet extends SpecificIterableFactory[Int, BitSet] { def empty: BitSet = immutable.BitSet.empty def newBuilder: Builder[Int, BitSet] = immutable.BitSet.newBuilder - def fromSpecific(it: IterableOnce[Int]): BitSet = immutable.BitSet.fromSpecific(it) + def fromSpecific(it: IterableOnce[Int]^): BitSet = immutable.BitSet.fromSpecific(it) @SerialVersionUID(3L) private[collection] abstract class SerializationProxy(@transient protected val coll: BitSet) extends Serializable { diff --git a/tests/pos-special/stdlib/collection/SortedSet.scala b/tests/pos-special/stdlib/collection/SortedSet.scala index c98ca9ae5523..fb2f879edcd2 100644 --- a/tests/pos-special/stdlib/collection/SortedSet.scala +++ b/tests/pos-special/stdlib/collection/SortedSet.scala @@ -14,6 +14,7 @@ package scala.collection import scala.annotation.{implicitNotFound, nowarn} import scala.annotation.unchecked.uncheckedVariance +import language.experimental.captureChecking /** Base type of sorted sets */ trait SortedSet[A] extends Set[A] @@ -68,7 +69,7 @@ trait SortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]] * @param start The lower-bound (inclusive) of the iterator */ def iteratorFrom(start: A): Iterator[A] - + @deprecated("Use `iteratorFrom` instead.", "2.13.0") @`inline` def keysIteratorFrom(start: A): Iterator[A] = iteratorFrom(start) @@ -178,7 +179,7 @@ object SortedSetOps { def flatMap[B : Ordering](f: A => IterableOnce[B]): CC[B] = self.sortedIterableFactory.from(new View.FlatMap(filtered, f)) - override def withFilter(q: A => Boolean): WithFilter[A, IterableCC, CC] = + override def withFilter(q: A => Boolean): WithFilter[A, IterableCC, CC]^{this, q} = new WithFilter[A, IterableCC, CC](self, (a: A) => p(a) && q(a)) } diff --git a/tests/pos-special/stdlib/collection/immutable/BitSet.scala b/tests/pos-special/stdlib/collection/immutable/BitSet.scala index 109f32d6f49a..9c2bfdad54d0 100644 --- a/tests/pos-special/stdlib/collection/immutable/BitSet.scala +++ b/tests/pos-special/stdlib/collection/immutable/BitSet.scala @@ -95,7 +95,7 @@ sealed abstract class BitSet @SerialVersionUID(3L) object BitSet extends SpecificIterableFactory[Int, BitSet] { - def fromSpecific(it: scala.collection.IterableOnce[Int]): BitSet = + def fromSpecific(it: scala.collection.IterableOnce[Int]^): BitSet = it match { case bs: BitSet => bs case _ => (newBuilder ++= it).result() diff --git a/tests/pos-special/stdlib/collection/immutable/SortedSet.scala b/tests/pos-special/stdlib/collection/immutable/SortedSet.scala index 303e5ea9658c..874abcaecda1 100644 --- a/tests/pos-special/stdlib/collection/immutable/SortedSet.scala +++ b/tests/pos-special/stdlib/collection/immutable/SortedSet.scala @@ -13,6 +13,7 @@ package scala package collection package immutable +import language.experimental.captureChecking /** Base trait for sorted sets */ trait SortedSet[A] @@ -50,7 +51,7 @@ trait StrictOptimizedSortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[ */ @SerialVersionUID(3L) object SortedSet extends SortedIterableFactory.Delegate[SortedSet](TreeSet) { - override def from[E: Ordering](it: IterableOnce[E]): SortedSet[E] = it match { + override def from[E: Ordering](it: IterableOnce[E]^): SortedSet[E] = it match { case ss: SortedSet[E] if Ordering[E] == ss.ordering => ss case _ => super.from(it) } diff --git a/tests/pos-special/stdlib/collection/mutable/BitSet.scala b/tests/pos-special/stdlib/collection/mutable/BitSet.scala index 17005fd16a9f..dcb8a157389b 100644 --- a/tests/pos-special/stdlib/collection/mutable/BitSet.scala +++ b/tests/pos-special/stdlib/collection/mutable/BitSet.scala @@ -361,7 +361,7 @@ class BitSet(protected[collection] final var elems: Array[Long]) @SerialVersionUID(3L) object BitSet extends SpecificIterableFactory[Int, BitSet] { - def fromSpecific(it: scala.collection.IterableOnce[Int]): BitSet = Growable.from(empty, it) + def fromSpecific(it: scala.collection.IterableOnce[Int]^): BitSet = Growable.from(empty, it) def empty: BitSet = new BitSet() diff --git a/tests/pos-special/stdlib/collection/mutable/SortedSet.scala b/tests/pos-special/stdlib/collection/mutable/SortedSet.scala index 2bcb8dc7845a..e657fb749d7d 100644 --- a/tests/pos-special/stdlib/collection/mutable/SortedSet.scala +++ b/tests/pos-special/stdlib/collection/mutable/SortedSet.scala @@ -13,6 +13,7 @@ package scala package collection package mutable +import language.experimental.captureChecking /** * Base type for mutable sorted set collections From 06744c2a42faf7fe1626672365ba3f71d61b8a47 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 22:56:06 +0100 Subject: [PATCH 34/89] Add BuildFrom.scala to stdlib --- .../stdlib/collection/BuildFrom.scala | 122 ++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/BuildFrom.scala diff --git a/tests/pos-special/stdlib/collection/BuildFrom.scala b/tests/pos-special/stdlib/collection/BuildFrom.scala new file mode 100644 index 000000000000..bc9c49d9493c --- /dev/null +++ b/tests/pos-special/stdlib/collection/BuildFrom.scala @@ -0,0 +1,122 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import scala.annotation.implicitNotFound +import scala.collection.mutable.Builder +import scala.collection.immutable.WrappedString +import scala.reflect.ClassTag + +/** Builds a collection of type `C` from elements of type `A` when a source collection of type `From` is available. + * Implicit instances of `BuildFrom` are available for all collection types. + * + * @tparam From Type of source collection + * @tparam A Type of elements (e.g. `Int`, `Boolean`, etc.) + * @tparam C Type of collection (e.g. `List[Int]`, `TreeMap[Int, String]`, etc.) + */ +@implicitNotFound(msg = "Cannot construct a collection of type ${C} with elements of type ${A} based on a collection of type ${From}.") +trait BuildFrom[-From, -A, +C] extends Any { self => + def fromSpecific(from: From)(it: IterableOnce[A]): C + + /** Get a Builder for the collection. For non-strict collection types this will use an intermediate buffer. + * Building collections with `fromSpecific` is preferred because it can be lazy for lazy collections. */ + def newBuilder(from: From): Builder[A, C] + + @deprecated("Use newBuilder() instead of apply()", "2.13.0") + @`inline` def apply(from: From): Builder[A, C] = newBuilder(from) + + /** Partially apply a BuildFrom to a Factory */ + def toFactory(from: From): Factory[A, C] = new Factory[A, C] { + def fromSpecific(it: IterableOnce[A]): C = self.fromSpecific(from)(it) + def newBuilder: Builder[A, C] = self.newBuilder(from) + } +} + +object BuildFrom extends BuildFromLowPriority1 { + + /** Build the source collection type from a MapOps */ + implicit def buildFromMapOps[CC[X, Y] <: Map[X, Y] with MapOps[X, Y, CC, _], K0, V0, K, V]: BuildFrom[CC[K0, V0] with Map[K0, V0], (K, V), CC[K, V] with Map[K, V]] = new BuildFrom[CC[K0, V0], (K, V), CC[K, V]] { + //TODO: Reuse a prototype instance + def newBuilder(from: CC[K0, V0]): Builder[(K, V), CC[K, V]] = (from: MapOps[K0, V0, CC, _]).mapFactory.newBuilder[K, V] + def fromSpecific(from: CC[K0, V0])(it: IterableOnce[(K, V)]): CC[K, V] = (from: MapOps[K0, V0, CC, _]).mapFactory.from(it) + } + + /** Build the source collection type from a SortedMapOps */ + implicit def buildFromSortedMapOps[CC[X, Y] <: SortedMap[X, Y] with SortedMapOps[X, Y, CC, _], K0, V0, K : Ordering, V]: BuildFrom[CC[K0, V0] with SortedMap[K0, V0], (K, V), CC[K, V] with SortedMap[K, V]] = new BuildFrom[CC[K0, V0], (K, V), CC[K, V]] { + def newBuilder(from: CC[K0, V0]): Builder[(K, V), CC[K, V]] = (from: SortedMapOps[K0, V0, CC, _]).sortedMapFactory.newBuilder[K, V] + def fromSpecific(from: CC[K0, V0])(it: IterableOnce[(K, V)]): CC[K, V] = (from: SortedMapOps[K0, V0, CC, _]).sortedMapFactory.from(it) + } + + implicit def buildFromBitSet[C <: BitSet with BitSetOps[C]]: BuildFrom[C, Int, C] = + new BuildFrom[C, Int, C] { + def fromSpecific(from: C)(it: IterableOnce[Int]): C = from.bitSetFactory.fromSpecific(it) + def newBuilder(from: C): Builder[Int, C] = from.bitSetFactory.newBuilder + } + + implicit val buildFromString: BuildFrom[String, Char, String] = + new BuildFrom[String, Char, String] { + def fromSpecific(from: String)(it: IterableOnce[Char]): String = Factory.stringFactory.fromSpecific(it) + def newBuilder(from: String): Builder[Char, String] = Factory.stringFactory.newBuilder + } + + implicit val buildFromWrappedString: BuildFrom[WrappedString, Char, WrappedString] = + new BuildFrom[WrappedString, Char, WrappedString] { + def fromSpecific(from: WrappedString)(it: IterableOnce[Char]): WrappedString = WrappedString.fromSpecific(it) + def newBuilder(from: WrappedString): mutable.Builder[Char, WrappedString] = WrappedString.newBuilder + } + + implicit def buildFromArray[A : ClassTag]: BuildFrom[Array[_], A, Array[A]] = + new BuildFrom[Array[_], A, Array[A]] { + def fromSpecific(from: Array[_])(it: IterableOnce[A]): Array[A] = Factory.arrayFactory[A].fromSpecific(it) + def newBuilder(from: Array[_]): Builder[A, Array[A]] = Factory.arrayFactory[A].newBuilder + } + + implicit def buildFromView[A, B]: BuildFrom[View[A], B, View[B]] = + new BuildFrom[View[A], B, View[B]] { + def fromSpecific(from: View[A])(it: IterableOnce[B]): View[B] = View.from(it) + def newBuilder(from: View[A]): Builder[B, View[B]] = View.newBuilder + } + +} + +trait BuildFromLowPriority1 extends BuildFromLowPriority2 { + + /** Build the source collection type from an Iterable with SortedOps */ + // Restating the upper bound of CC in the result type seems redundant, but it serves to prune the + // implicit search space for faster compilation and reduced change of divergence. See the compilation + // test in test/junit/scala/collection/BuildFromTest.scala and discussion in https://github.com/scala/scala/pull/10209 + implicit def buildFromSortedSetOps[CC[X] <: SortedSet[X] with SortedSetOps[X, CC, _], A0, A : Ordering]: BuildFrom[CC[A0] with SortedSet[A0], A, CC[A] with SortedSet[A]] = new BuildFrom[CC[A0], A, CC[A]] { + def newBuilder(from: CC[A0]): Builder[A, CC[A]] = (from: SortedSetOps[A0, CC, _]).sortedIterableFactory.newBuilder[A] + def fromSpecific(from: CC[A0])(it: IterableOnce[A]): CC[A] = (from: SortedSetOps[A0, CC, _]).sortedIterableFactory.from(it) + } + + implicit def fallbackStringCanBuildFrom[A]: BuildFrom[String, A, immutable.IndexedSeq[A]] = + new BuildFrom[String, A, immutable.IndexedSeq[A]] { + def fromSpecific(from: String)(it: IterableOnce[A]): immutable.IndexedSeq[A] = immutable.IndexedSeq.from(it) + def newBuilder(from: String): Builder[A, immutable.IndexedSeq[A]] = immutable.IndexedSeq.newBuilder[A] + } +} + +trait BuildFromLowPriority2 { + /** Build the source collection type from an IterableOps */ + implicit def buildFromIterableOps[CC[X] <: Iterable[X] with IterableOps[X, CC, _], A0, A]: BuildFrom[CC[A0], A, CC[A]] = new BuildFrom[CC[A0], A, CC[A]] { + //TODO: Reuse a prototype instance + def newBuilder(from: CC[A0]): Builder[A, CC[A]] = (from: IterableOps[A0, CC, _]).iterableFactory.newBuilder[A] + def fromSpecific(from: CC[A0])(it: IterableOnce[A]): CC[A] = (from: IterableOps[A0, CC, _]).iterableFactory.from(it) + } + + implicit def buildFromIterator[A]: BuildFrom[Iterator[_], A, Iterator[A]] = new BuildFrom[Iterator[_], A, Iterator[A]] { + def newBuilder(from: Iterator[_]): mutable.Builder[A, Iterator[A]] = Iterator.newBuilder + def fromSpecific(from: Iterator[_])(it: IterableOnce[A]): Iterator[A] = Iterator.from(it) + } +} From 51c9385101bef1a9b7db79553112763ab6dfdf44 Mon Sep 17 00:00:00 2001 From: odersky Date: Tue, 31 Oct 2023 23:13:26 +0100 Subject: [PATCH 35/89] Make BuildFrom capture checked --- .../stdlib/collection/BuildFrom.scala | 36 +++++++++++-------- .../stdlib/collection/Factory.scala | 7 ++-- 2 files changed, 25 insertions(+), 18 deletions(-) diff --git a/tests/pos-special/stdlib/collection/BuildFrom.scala b/tests/pos-special/stdlib/collection/BuildFrom.scala index bc9c49d9493c..15a8acf2e6ef 100644 --- a/tests/pos-special/stdlib/collection/BuildFrom.scala +++ b/tests/pos-special/stdlib/collection/BuildFrom.scala @@ -16,6 +16,8 @@ import scala.annotation.implicitNotFound import scala.collection.mutable.Builder import scala.collection.immutable.WrappedString import scala.reflect.ClassTag +import language.experimental.captureChecking +import caps.unsafe.unsafeAssumePure /** Builds a collection of type `C` from elements of type `A` when a source collection of type `From` is available. * Implicit instances of `BuildFrom` are available for all collection types. @@ -26,7 +28,11 @@ import scala.reflect.ClassTag */ @implicitNotFound(msg = "Cannot construct a collection of type ${C} with elements of type ${A} based on a collection of type ${From}.") trait BuildFrom[-From, -A, +C] extends Any { self => - def fromSpecific(from: From)(it: IterableOnce[A]): C + def fromSpecific(from: From)(it: IterableOnce[A]^): C + // !!! this is wrong, we need two versions of fromSpecific; one mapping + // to C^{it} when C is an Iterable, and one mapping to C when C is a Seq, Map, or Set. + // But that requires a lareg scale refactoring of BuildFrom. The unsafeAssumePure + // calls in this file are needed to sweep that problem under the carpet. /** Get a Builder for the collection. For non-strict collection types this will use an intermediate buffer. * Building collections with `fromSpecific` is preferred because it can be lazy for lazy collections. */ @@ -37,7 +43,7 @@ trait BuildFrom[-From, -A, +C] extends Any { self => /** Partially apply a BuildFrom to a Factory */ def toFactory(from: From): Factory[A, C] = new Factory[A, C] { - def fromSpecific(it: IterableOnce[A]): C = self.fromSpecific(from)(it) + def fromSpecific(it: IterableOnce[A]^): C = self.fromSpecific(from)(it) def newBuilder: Builder[A, C] = self.newBuilder(from) } } @@ -48,42 +54,42 @@ object BuildFrom extends BuildFromLowPriority1 { implicit def buildFromMapOps[CC[X, Y] <: Map[X, Y] with MapOps[X, Y, CC, _], K0, V0, K, V]: BuildFrom[CC[K0, V0] with Map[K0, V0], (K, V), CC[K, V] with Map[K, V]] = new BuildFrom[CC[K0, V0], (K, V), CC[K, V]] { //TODO: Reuse a prototype instance def newBuilder(from: CC[K0, V0]): Builder[(K, V), CC[K, V]] = (from: MapOps[K0, V0, CC, _]).mapFactory.newBuilder[K, V] - def fromSpecific(from: CC[K0, V0])(it: IterableOnce[(K, V)]): CC[K, V] = (from: MapOps[K0, V0, CC, _]).mapFactory.from(it) + def fromSpecific(from: CC[K0, V0])(it: IterableOnce[(K, V)]^): CC[K, V] = (from: MapOps[K0, V0, CC, _]).mapFactory.from(it) } /** Build the source collection type from a SortedMapOps */ implicit def buildFromSortedMapOps[CC[X, Y] <: SortedMap[X, Y] with SortedMapOps[X, Y, CC, _], K0, V0, K : Ordering, V]: BuildFrom[CC[K0, V0] with SortedMap[K0, V0], (K, V), CC[K, V] with SortedMap[K, V]] = new BuildFrom[CC[K0, V0], (K, V), CC[K, V]] { def newBuilder(from: CC[K0, V0]): Builder[(K, V), CC[K, V]] = (from: SortedMapOps[K0, V0, CC, _]).sortedMapFactory.newBuilder[K, V] - def fromSpecific(from: CC[K0, V0])(it: IterableOnce[(K, V)]): CC[K, V] = (from: SortedMapOps[K0, V0, CC, _]).sortedMapFactory.from(it) + def fromSpecific(from: CC[K0, V0])(it: IterableOnce[(K, V)]^): CC[K, V] = (from: SortedMapOps[K0, V0, CC, _]).sortedMapFactory.from(it) } implicit def buildFromBitSet[C <: BitSet with BitSetOps[C]]: BuildFrom[C, Int, C] = new BuildFrom[C, Int, C] { - def fromSpecific(from: C)(it: IterableOnce[Int]): C = from.bitSetFactory.fromSpecific(it) + def fromSpecific(from: C)(it: IterableOnce[Int]^): C = from.bitSetFactory.fromSpecific(it) def newBuilder(from: C): Builder[Int, C] = from.bitSetFactory.newBuilder } implicit val buildFromString: BuildFrom[String, Char, String] = new BuildFrom[String, Char, String] { - def fromSpecific(from: String)(it: IterableOnce[Char]): String = Factory.stringFactory.fromSpecific(it) + def fromSpecific(from: String)(it: IterableOnce[Char]^): String = Factory.stringFactory.fromSpecific(it) def newBuilder(from: String): Builder[Char, String] = Factory.stringFactory.newBuilder } implicit val buildFromWrappedString: BuildFrom[WrappedString, Char, WrappedString] = new BuildFrom[WrappedString, Char, WrappedString] { - def fromSpecific(from: WrappedString)(it: IterableOnce[Char]): WrappedString = WrappedString.fromSpecific(it) + def fromSpecific(from: WrappedString)(it: IterableOnce[Char]^): WrappedString = WrappedString.fromSpecific(it) def newBuilder(from: WrappedString): mutable.Builder[Char, WrappedString] = WrappedString.newBuilder } - implicit def buildFromArray[A : ClassTag]: BuildFrom[Array[_], A, Array[A]] = + implicit def buildFromArray[sealed A : ClassTag]: BuildFrom[Array[_], A, Array[A]] = new BuildFrom[Array[_], A, Array[A]] { - def fromSpecific(from: Array[_])(it: IterableOnce[A]): Array[A] = Factory.arrayFactory[A].fromSpecific(it) + def fromSpecific(from: Array[_])(it: IterableOnce[A]^): Array[A] = Factory.arrayFactory[A].fromSpecific(it) def newBuilder(from: Array[_]): Builder[A, Array[A]] = Factory.arrayFactory[A].newBuilder } - implicit def buildFromView[A, B]: BuildFrom[View[A], B, View[B]] = + implicit def buildFromView[A, sealed B]: BuildFrom[View[A], B, View[B]] = new BuildFrom[View[A], B, View[B]] { - def fromSpecific(from: View[A])(it: IterableOnce[B]): View[B] = View.from(it) + def fromSpecific(from: View[A])(it: IterableOnce[B]^): View[B] = View.from(it).unsafeAssumePure def newBuilder(from: View[A]): Builder[B, View[B]] = View.newBuilder } @@ -97,12 +103,12 @@ trait BuildFromLowPriority1 extends BuildFromLowPriority2 { // test in test/junit/scala/collection/BuildFromTest.scala and discussion in https://github.com/scala/scala/pull/10209 implicit def buildFromSortedSetOps[CC[X] <: SortedSet[X] with SortedSetOps[X, CC, _], A0, A : Ordering]: BuildFrom[CC[A0] with SortedSet[A0], A, CC[A] with SortedSet[A]] = new BuildFrom[CC[A0], A, CC[A]] { def newBuilder(from: CC[A0]): Builder[A, CC[A]] = (from: SortedSetOps[A0, CC, _]).sortedIterableFactory.newBuilder[A] - def fromSpecific(from: CC[A0])(it: IterableOnce[A]): CC[A] = (from: SortedSetOps[A0, CC, _]).sortedIterableFactory.from(it) + def fromSpecific(from: CC[A0])(it: IterableOnce[A]^): CC[A] = (from: SortedSetOps[A0, CC, _]).sortedIterableFactory.from(it) } implicit def fallbackStringCanBuildFrom[A]: BuildFrom[String, A, immutable.IndexedSeq[A]] = new BuildFrom[String, A, immutable.IndexedSeq[A]] { - def fromSpecific(from: String)(it: IterableOnce[A]): immutable.IndexedSeq[A] = immutable.IndexedSeq.from(it) + def fromSpecific(from: String)(it: IterableOnce[A]^): immutable.IndexedSeq[A] = immutable.IndexedSeq.from(it) def newBuilder(from: String): Builder[A, immutable.IndexedSeq[A]] = immutable.IndexedSeq.newBuilder[A] } } @@ -112,11 +118,11 @@ trait BuildFromLowPriority2 { implicit def buildFromIterableOps[CC[X] <: Iterable[X] with IterableOps[X, CC, _], A0, A]: BuildFrom[CC[A0], A, CC[A]] = new BuildFrom[CC[A0], A, CC[A]] { //TODO: Reuse a prototype instance def newBuilder(from: CC[A0]): Builder[A, CC[A]] = (from: IterableOps[A0, CC, _]).iterableFactory.newBuilder[A] - def fromSpecific(from: CC[A0])(it: IterableOnce[A]): CC[A] = (from: IterableOps[A0, CC, _]).iterableFactory.from(it) + def fromSpecific(from: CC[A0])(it: IterableOnce[A]^): CC[A] = (from: IterableOps[A0, CC, _]).iterableFactory.from(it).unsafeAssumePure } implicit def buildFromIterator[A]: BuildFrom[Iterator[_], A, Iterator[A]] = new BuildFrom[Iterator[_], A, Iterator[A]] { def newBuilder(from: Iterator[_]): mutable.Builder[A, Iterator[A]] = Iterator.newBuilder - def fromSpecific(from: Iterator[_])(it: IterableOnce[A]): Iterator[A] = Iterator.from(it) + def fromSpecific(from: Iterator[_])(it: IterableOnce[A]^): Iterator[A] = Iterator.from(it).unsafeAssumePure } } diff --git a/tests/pos-special/stdlib/collection/Factory.scala b/tests/pos-special/stdlib/collection/Factory.scala index 9979ef1bd619..c45776b62b9c 100644 --- a/tests/pos-special/stdlib/collection/Factory.scala +++ b/tests/pos-special/stdlib/collection/Factory.scala @@ -282,7 +282,8 @@ object IterableFactory { implicit def toBuildFrom[A, CC[_]](factory: IterableFactory[CC]): BuildFrom[Any, A, CC[A]] = new BuildFrom[Any, A, CC[A]] { - def fromSpecific(from: Any)(it: IterableOnce[A]^): CC[A]^{it} = factory.from(it) + def fromSpecific(from: Any)(it: IterableOnce[A]^): CC[A] = + factory.from(it).unsafeAssumePure // !!! see remark in BuildFrom why this is necessary def newBuilder(from: Any) = factory.newBuilder } @@ -535,7 +536,7 @@ object EvidenceIterableFactory { implicit def toBuildFrom[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]): BuildFrom[Any, A, CC[A]] = new EvidenceIterableFactoryToBuildFrom(factory) private class EvidenceIterableFactoryToBuildFrom[Ev[_], A: Ev, CC[_]](factory: EvidenceIterableFactory[CC, Ev]) extends BuildFrom[Any, A, CC[A]] { - def fromSpecific(from: Any)(it: IterableOnce[A]): CC[A] = factory.from[A](it) + def fromSpecific(from: Any)(it: IterableOnce[A]^): CC[A] = factory.from[A](it) def newBuilder(from: Any): Builder[A, CC[A]] = factory.newBuilder[A] } @@ -783,7 +784,7 @@ object SortedMapFactory { implicit def toBuildFrom[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]): BuildFrom[Any, (K, V), CC[K, V]] = new SortedMapFactoryToBuildFrom(factory) private class SortedMapFactoryToBuildFrom[K : Ordering, V, CC[_, _]](factory: SortedMapFactory[CC]) extends BuildFrom[Any, (K, V), CC[K, V]] { - def fromSpecific(from: Any)(it: IterableOnce[(K, V)]) = factory.from(it) + def fromSpecific(from: Any)(it: IterableOnce[(K, V)]^) = factory.from(it) def newBuilder(from: Any) = factory.newBuilder[K, V] } From 238317c2f73cec3da48304e37087cbe6d93a81aa Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 09:33:43 +0100 Subject: [PATCH 36/89] Add WithFilter.scala to stdlib --- .../stdlib/collection/WithFilter.scala | 70 +++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/WithFilter.scala diff --git a/tests/pos-special/stdlib/collection/WithFilter.scala b/tests/pos-special/stdlib/collection/WithFilter.scala new file mode 100644 index 000000000000..4699abbef5a7 --- /dev/null +++ b/tests/pos-special/stdlib/collection/WithFilter.scala @@ -0,0 +1,70 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +/** A template trait that contains just the `map`, `flatMap`, `foreach` and `withFilter` methods + * of trait `Iterable`. + * + * @tparam A Element type (e.g. `Int`) + * @tparam CC Collection type constructor (e.g. `List`) + * + * @define coll collection + */ +@SerialVersionUID(3L) +abstract class WithFilter[+A, +CC[_]] extends Serializable { + + /** Builds a new collection by applying a function to all elements of the + * `filtered` outer $coll. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned collection. + * @return a new $coll resulting from applying + * the given function `f` to each element of the filtered outer $coll + * and collecting the results. + */ + def map[B](f: A => B): CC[B] + + /** Builds a new collection by applying a function to all elements of the + * `filtered` outer $coll containing this `WithFilter` instance that satisfy + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned collection. + * @return a new $coll resulting from applying + * the given collection-valued function `f` to each element + * of the filtered outer $coll and + * concatenating the results. + */ + def flatMap[B](f: A => IterableOnce[B]): CC[B] + + /** Applies a function `f` to all elements of the `filtered` outer $coll. + * + * @param f the function that is applied for its side-effect to every element. + * The result of function `f` is discarded. + * + * @tparam U the type parameter describing the result of function `f`. + * This result will always be ignored. Typically `U` is `Unit`, + * but this is not necessary. + */ + def foreach[U](f: A => U): Unit + + /** Further refines the filter for this `filtered` $coll. + * + * @param q the predicate used to test elements. + * @return an object of class `WithFilter`, which supports + * `map`, `flatMap`, `foreach`, and `withFilter` operations. + * All these operations apply to those elements of this $coll which + * also satisfy both `p` and `q` predicates. + */ + def withFilter(q: A => Boolean): WithFilter[A, CC] + +} From 1b757b9e5b9ced9ca59245d7551f5650f760932c Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 09:38:01 +0100 Subject: [PATCH 37/89] Make WithFilter capture checked --- tests/pos-special/stdlib/collection/Iterable.scala | 2 +- tests/pos-special/stdlib/collection/Map.scala | 6 +++--- tests/pos-special/stdlib/collection/WithFilter.scala | 8 +++++--- 3 files changed, 9 insertions(+), 7 deletions(-) diff --git a/tests/pos-special/stdlib/collection/Iterable.scala b/tests/pos-special/stdlib/collection/Iterable.scala index 7b5eb39314d3..491d78a797dd 100644 --- a/tests/pos-special/stdlib/collection/Iterable.scala +++ b/tests/pos-special/stdlib/collection/Iterable.scala @@ -905,7 +905,7 @@ object IterableOps { def map[B](f: A => B): CC[B]^{this, f} = self.iterableFactory.from(new View.Map(filtered, f)) - def flatMap[B](f: A => IterableOnce[B]): CC[B]^{this, f} = + def flatMap[B](f: A => IterableOnce[B]^): CC[B]^{this, f} = self.iterableFactory.from(new View.FlatMap(filtered, f)) def foreach[U](f: A => U): Unit = filtered.foreach(f) diff --git a/tests/pos-special/stdlib/collection/Map.scala b/tests/pos-special/stdlib/collection/Map.scala index ef4f915ea573..bcfd8d593eda 100644 --- a/tests/pos-special/stdlib/collection/Map.scala +++ b/tests/pos-special/stdlib/collection/Map.scala @@ -378,13 +378,13 @@ object MapOps { p: ((K, V)) => Boolean ) extends IterableOps.WithFilter[(K, V), IterableCC](self, p) with Serializable { - def map[K2, V2](f: ((K, V)) => (K2, V2)): CC[K2, V2] = + def map[K2, V2](f: ((K, V)) => (K2, V2)): CC[K2, V2]^{this, f} = self.mapFactory.from(new View.Map(filtered, f)) - def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)]^): CC[K2, V2] = + def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)]^): CC[K2, V2]^{this, f} = self.mapFactory.from(new View.FlatMap(filtered, f)) - override def withFilter(q: ((K, V)) => Boolean): WithFilter[K, V, IterableCC, CC]^{p, q} = + override def withFilter(q: ((K, V)) => Boolean): WithFilter[K, V, IterableCC, CC]^{this, q} = new WithFilter[K, V, IterableCC, CC](self, (kv: (K, V)) => p(kv) && q(kv)) } diff --git a/tests/pos-special/stdlib/collection/WithFilter.scala b/tests/pos-special/stdlib/collection/WithFilter.scala index 4699abbef5a7..0f3830e9fe25 100644 --- a/tests/pos-special/stdlib/collection/WithFilter.scala +++ b/tests/pos-special/stdlib/collection/WithFilter.scala @@ -11,6 +11,7 @@ */ package scala.collection +import language.experimental.captureChecking /** A template trait that contains just the `map`, `flatMap`, `foreach` and `withFilter` methods * of trait `Iterable`. @@ -22,6 +23,7 @@ package scala.collection */ @SerialVersionUID(3L) abstract class WithFilter[+A, +CC[_]] extends Serializable { + this: WithFilter[A, CC]^ => /** Builds a new collection by applying a function to all elements of the * `filtered` outer $coll. @@ -32,7 +34,7 @@ abstract class WithFilter[+A, +CC[_]] extends Serializable { * the given function `f` to each element of the filtered outer $coll * and collecting the results. */ - def map[B](f: A => B): CC[B] + def map[B](f: A => B): CC[B]^{this, f} /** Builds a new collection by applying a function to all elements of the * `filtered` outer $coll containing this `WithFilter` instance that satisfy @@ -44,7 +46,7 @@ abstract class WithFilter[+A, +CC[_]] extends Serializable { * of the filtered outer $coll and * concatenating the results. */ - def flatMap[B](f: A => IterableOnce[B]): CC[B] + def flatMap[B](f: A => IterableOnce[B]^): CC[B]^{this, f} /** Applies a function `f` to all elements of the `filtered` outer $coll. * @@ -65,6 +67,6 @@ abstract class WithFilter[+A, +CC[_]] extends Serializable { * All these operations apply to those elements of this $coll which * also satisfy both `p` and `q` predicates. */ - def withFilter(q: A => Boolean): WithFilter[A, CC] + def withFilter(q: A => Boolean): WithFilter[A, CC]^{this, q} } From 4956e6d80d94ee0552d6229f2bbd93a669fa34da Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 09:39:53 +0100 Subject: [PATCH 38/89] Add ArrayOps to stdlib --- .../stdlib/collection/ArrayOps.scala | 1663 +++++++++++++++++ 1 file changed, 1663 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/ArrayOps.scala diff --git a/tests/pos-special/stdlib/collection/ArrayOps.scala b/tests/pos-special/stdlib/collection/ArrayOps.scala new file mode 100644 index 000000000000..485427886625 --- /dev/null +++ b/tests/pos-special/stdlib/collection/ArrayOps.scala @@ -0,0 +1,1663 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import java.lang.Math.{max, min} +import java.util.Arrays + +import scala.Predef.{ // unimport all array-related implicit conversions to avoid triggering them accidentally + genericArrayOps => _, + booleanArrayOps => _, + byteArrayOps => _, + charArrayOps => _, + doubleArrayOps => _, + floatArrayOps => _, + intArrayOps => _, + longArrayOps => _, + refArrayOps => _, + shortArrayOps => _, + unitArrayOps => _, + genericWrapArray => _, + wrapRefArray => _, + wrapIntArray => _, + wrapDoubleArray => _, + wrapLongArray => _, + wrapFloatArray => _, + wrapCharArray => _, + wrapByteArray => _, + wrapShortArray => _, + wrapBooleanArray => _, + wrapUnitArray => _, + wrapString => _, + copyArrayToImmutableIndexedSeq => _, + _ +} +import scala.collection.Stepper.EfficientSplit +import scala.collection.immutable.Range +import scala.collection.mutable.ArrayBuilder +import scala.math.Ordering +import scala.reflect.ClassTag +import scala.util.Sorting + +object ArrayOps { + + @SerialVersionUID(3L) + private class ArrayView[A](xs: Array[A]) extends AbstractIndexedSeqView[A] { + def length = xs.length + def apply(n: Int) = xs(n) + override def toString: String = immutable.ArraySeq.unsafeWrapArray(xs).mkString("ArrayView(", ", ", ")") + } + + /** A lazy filtered array. No filtering is applied until one of `foreach`, `map` or `flatMap` is called. */ + class WithFilter[A](p: A => Boolean, xs: Array[A]) { + + /** Apply `f` to each element for its side effects. + * Note: [U] parameter needed to help scalac's type inference. + */ + def foreach[U](f: A => U): Unit = { + val len = xs.length + var i = 0 + while(i < len) { + val x = xs(i) + if(p(x)) f(x) + i += 1 + } + } + + /** Builds a new array by applying a function to all elements of this array. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned array. + * @return a new array resulting from applying the given function + * `f` to each element of this array and collecting the results. + */ + def map[B: ClassTag](f: A => B): Array[B] = { + val b = ArrayBuilder.make[B] + var i = 0 + while (i < xs.length) { + val x = xs(i) + if(p(x)) b += f(x) + i = i + 1 + } + b.result() + } + + /** Builds a new array by applying a function to all elements of this array + * and using the elements of the resulting collections. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned array. + * @return a new array resulting from applying the given collection-valued function + * `f` to each element of this array and concatenating the results. + */ + def flatMap[B: ClassTag](f: A => IterableOnce[B]): Array[B] = { + val b = ArrayBuilder.make[B] + var i = 0 + while(i < xs.length) { + val x = xs(i) + if(p(x)) b ++= f(xs(i)) + i += 1 + } + b.result() + } + + def flatMap[BS, B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B] = + flatMap[B](x => asIterable(f(x))) + + /** Creates a new non-strict filter which combines this filter with the given predicate. */ + def withFilter(q: A => Boolean): WithFilter[A] = new WithFilter[A](a => p(a) && q(a), xs) + } + + @SerialVersionUID(3L) + private[collection] final class ArrayIterator[@specialized(Specializable.Everything) A](xs: Array[A]) extends AbstractIterator[A] with Serializable { + private[this] var pos = 0 + private[this] val len = xs.length + override def knownSize: Int = len - pos + def hasNext: Boolean = pos < len + def next(): A = { + if (pos >= xs.length) Iterator.empty.next() + val r = xs(pos) + pos += 1 + r + } + override def drop(n: Int): Iterator[A] = { + if (n > 0) { + val newPos = pos + n + pos = + if (newPos < 0 /* overflow */) len + else Math.min(len, newPos) + } + this + } + } + + @SerialVersionUID(3L) + private final class ReverseIterator[@specialized(Specializable.Everything) A](xs: Array[A]) extends AbstractIterator[A] with Serializable { + private[this] var pos = xs.length-1 + def hasNext: Boolean = pos >= 0 + def next(): A = { + if (pos < 0) Iterator.empty.next() + val r = xs(pos) + pos -= 1 + r + } + + override def drop(n: Int): Iterator[A] = { + if (n > 0) pos = Math.max( -1, pos - n) + this + } + } + + @SerialVersionUID(3L) + private final class GroupedIterator[A](xs: Array[A], groupSize: Int) extends AbstractIterator[Array[A]] with Serializable { + private[this] var pos = 0 + def hasNext: Boolean = pos < xs.length + def next(): Array[A] = { + if(pos >= xs.length) throw new NoSuchElementException + val r = new ArrayOps(xs).slice(pos, pos+groupSize) + pos += groupSize + r + } + } + + /** The cut-off point for the array size after which we switch from `Sorting.stableSort` to + * an implementation that copies the data to a boxed representation for use with `Arrays.sort`. + */ + private final val MaxStableSortLength = 300 + + /** Avoid an allocation in [[collect]]. */ + private val fallback: Any => Any = _ => fallback +} + +/** This class serves as a wrapper for `Array`s with many of the operations found in + * indexed sequences. Where needed, instances of arrays are implicitly converted + * into this class. There is generally no reason to create an instance explicitly or use + * an `ArrayOps` type. It is better to work with plain `Array` types instead and rely on + * the implicit conversion to `ArrayOps` when calling a method (which does not actually + * allocate an instance of `ArrayOps` because it is a value class). + * + * Neither `Array` nor `ArrayOps` are proper collection types + * (i.e. they do not extend `Iterable` or even `IterableOnce`). `mutable.ArraySeq` and + * `immutable.ArraySeq` serve this purpose. + * + * The difference between this class and `ArraySeq`s is that calling transformer methods such as + * `filter` and `map` will yield an array, whereas an `ArraySeq` will remain an `ArraySeq`. + * + * @tparam A type of the elements contained in this array. + */ +final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { + + @`inline` private[this] implicit def elemTag: ClassTag[A] = ClassTag(xs.getClass.getComponentType) + + /** The size of this array. + * + * @return the number of elements in this array. + */ + @`inline` def size: Int = xs.length + + /** The size of this array. + * + * @return the number of elements in this array. + */ + @`inline` def knownSize: Int = xs.length + + /** Tests whether the array is empty. + * + * @return `true` if the array contains no elements, `false` otherwise. + */ + @`inline` def isEmpty: Boolean = xs.length == 0 + + /** Tests whether the array is not empty. + * + * @return `true` if the array contains at least one element, `false` otherwise. + */ + @`inline` def nonEmpty: Boolean = xs.length != 0 + + /** Selects the first element of this array. + * + * @return the first element of this array. + * @throws NoSuchElementException if the array is empty. + */ + def head: A = if (nonEmpty) xs.apply(0) else throw new NoSuchElementException("head of empty array") + + /** Selects the last element. + * + * @return The last element of this array. + * @throws NoSuchElementException If the array is empty. + */ + def last: A = if (nonEmpty) xs.apply(xs.length-1) else throw new NoSuchElementException("last of empty array") + + /** Optionally selects the first element. + * + * @return the first element of this array if it is nonempty, + * `None` if it is empty. + */ + def headOption: Option[A] = if(isEmpty) None else Some(head) + + /** Optionally selects the last element. + * + * @return the last element of this array$ if it is nonempty, + * `None` if it is empty. + */ + def lastOption: Option[A] = if(isEmpty) None else Some(last) + + /** Compares the size of this array to a test value. + * + * @param otherSize the test value that gets compared with the size. + * @return A value `x` where + * {{{ + * x < 0 if this.size < otherSize + * x == 0 if this.size == otherSize + * x > 0 if this.size > otherSize + * }}} + */ + def sizeCompare(otherSize: Int): Int = Integer.compare(xs.length, otherSize) + + /** Compares the length of this array to a test value. + * + * @param len the test value that gets compared with the length. + * @return A value `x` where + * {{{ + * x < 0 if this.length < len + * x == 0 if this.length == len + * x > 0 if this.length > len + * }}} + */ + def lengthCompare(len: Int): Int = Integer.compare(xs.length, len) + + /** Method mirroring [[SeqOps.sizeIs]] for consistency, except it returns an `Int` + * because `size` is known and comparison is constant-time. + * + * These operations are equivalent to [[sizeCompare(Int) `sizeCompare(Int)`]], and + * allow the following more readable usages: + * + * {{{ + * this.sizeIs < size // this.sizeCompare(size) < 0 + * this.sizeIs <= size // this.sizeCompare(size) <= 0 + * this.sizeIs == size // this.sizeCompare(size) == 0 + * this.sizeIs != size // this.sizeCompare(size) != 0 + * this.sizeIs >= size // this.sizeCompare(size) >= 0 + * this.sizeIs > size // this.sizeCompare(size) > 0 + * }}} + */ + def sizeIs: Int = xs.length + + /** Method mirroring [[SeqOps.lengthIs]] for consistency, except it returns an `Int` + * because `length` is known and comparison is constant-time. + * + * These operations are equivalent to [[lengthCompare(Int) `lengthCompare(Int)`]], and + * allow the following more readable usages: + * + * {{{ + * this.lengthIs < len // this.lengthCompare(len) < 0 + * this.lengthIs <= len // this.lengthCompare(len) <= 0 + * this.lengthIs == len // this.lengthCompare(len) == 0 + * this.lengthIs != len // this.lengthCompare(len) != 0 + * this.lengthIs >= len // this.lengthCompare(len) >= 0 + * this.lengthIs > len // this.lengthCompare(len) > 0 + * }}} + */ + def lengthIs: Int = xs.length + + /** Selects an interval of elements. The returned array is made up + * of all elements `x` which satisfy the invariant: + * {{{ + * from <= indexOf(x) < until + * }}} + * + * @param from the lowest index to include from this array. + * @param until the lowest index to EXCLUDE from this array. + * @return an array containing the elements greater than or equal to + * index `from` extending up to (but not including) index `until` + * of this array. + */ + def slice(from: Int, until: Int): Array[A] = { + import java.util.Arrays.copyOfRange + val lo = max(from, 0) + val hi = min(until, xs.length) + if (hi > lo) { + (((xs: Array[_]): @unchecked) match { + case x: Array[AnyRef] => copyOfRange(x, lo, hi) + case x: Array[Int] => copyOfRange(x, lo, hi) + case x: Array[Double] => copyOfRange(x, lo, hi) + case x: Array[Long] => copyOfRange(x, lo, hi) + case x: Array[Float] => copyOfRange(x, lo, hi) + case x: Array[Char] => copyOfRange(x, lo, hi) + case x: Array[Byte] => copyOfRange(x, lo, hi) + case x: Array[Short] => copyOfRange(x, lo, hi) + case x: Array[Boolean] => copyOfRange(x, lo, hi) + }).asInstanceOf[Array[A]] + } else new Array[A](0) + } + + /** The rest of the array without its first element. */ + def tail: Array[A] = + if(xs.length == 0) throw new UnsupportedOperationException("tail of empty array") else slice(1, xs.length) + + /** The initial part of the array without its last element. */ + def init: Array[A] = + if(xs.length == 0) throw new UnsupportedOperationException("init of empty array") else slice(0, xs.length-1) + + /** Iterates over the tails of this array. The first value will be this + * array and the final one will be an empty array, with the intervening + * values the results of successive applications of `tail`. + * + * @return an iterator over all the tails of this array + */ + def tails: Iterator[Array[A]] = iterateUntilEmpty(xs => new ArrayOps(xs).tail) + + /** Iterates over the inits of this array. The first value will be this + * array and the final one will be an empty array, with the intervening + * values the results of successive applications of `init`. + * + * @return an iterator over all the inits of this array + */ + def inits: Iterator[Array[A]] = iterateUntilEmpty(xs => new ArrayOps(xs).init) + + // A helper for tails and inits. + private[this] def iterateUntilEmpty(f: Array[A] => Array[A]): Iterator[Array[A]] = + Iterator.iterate(xs)(f).takeWhile(x => x.length != 0) ++ Iterator.single(Array.empty[A]) + + /** An array containing the first `n` elements of this array. */ + def take(n: Int): Array[A] = slice(0, n) + + /** The rest of the array without its `n` first elements. */ + def drop(n: Int): Array[A] = slice(n, xs.length) + + /** An array containing the last `n` elements of this array. */ + def takeRight(n: Int): Array[A] = drop(xs.length - max(n, 0)) + + /** The rest of the array without its `n` last elements. */ + def dropRight(n: Int): Array[A] = take(xs.length - max(n, 0)) + + /** Takes longest prefix of elements that satisfy a predicate. + * + * @param p The predicate used to test elements. + * @return the longest prefix of this array whose elements all satisfy + * the predicate `p`. + */ + def takeWhile(p: A => Boolean): Array[A] = { + val i = indexWhere(x => !p(x)) + val hi = if(i < 0) xs.length else i + slice(0, hi) + } + + /** Drops longest prefix of elements that satisfy a predicate. + * + * @param p The predicate used to test elements. + * @return the longest suffix of this array whose first element + * does not satisfy the predicate `p`. + */ + def dropWhile(p: A => Boolean): Array[A] = { + val i = indexWhere(x => !p(x)) + val lo = if(i < 0) xs.length else i + slice(lo, xs.length) + } + + def iterator: Iterator[A] = + ((xs: Any @unchecked) match { + case xs: Array[AnyRef] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Int] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Double] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Long] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Float] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Char] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Byte] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Short] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Boolean] => new ArrayOps.ArrayIterator(xs) + case xs: Array[Unit] => new ArrayOps.ArrayIterator(xs) + case null => throw new NullPointerException + }).asInstanceOf[Iterator[A]] + + def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + import convert.impl._ + val s = (shape.shape: @unchecked) match { + case StepperShape.ReferenceShape => (xs: Any) match { + case bs: Array[Boolean] => new BoxedBooleanArrayStepper(bs, 0, xs.length) + case _ => new ObjectArrayStepper[AnyRef](xs.asInstanceOf[Array[AnyRef ]], 0, xs.length) + } + case StepperShape.IntShape => new IntArrayStepper (xs.asInstanceOf[Array[Int ]], 0, xs.length) + case StepperShape.LongShape => new LongArrayStepper (xs.asInstanceOf[Array[Long ]], 0, xs.length) + case StepperShape.DoubleShape => new DoubleArrayStepper (xs.asInstanceOf[Array[Double ]], 0, xs.length) + case StepperShape.ByteShape => new WidenedByteArrayStepper (xs.asInstanceOf[Array[Byte ]], 0, xs.length) + case StepperShape.ShortShape => new WidenedShortArrayStepper (xs.asInstanceOf[Array[Short ]], 0, xs.length) + case StepperShape.CharShape => new WidenedCharArrayStepper (xs.asInstanceOf[Array[Char ]], 0, xs.length) + case StepperShape.FloatShape => new WidenedFloatArrayStepper (xs.asInstanceOf[Array[Float ]], 0, xs.length) + } + s.asInstanceOf[S with EfficientSplit] + } + + /** Partitions elements in fixed size arrays. + * @see [[scala.collection.Iterator]], method `grouped` + * + * @param size the number of elements per group + * @return An iterator producing arrays of size `size`, except the + * last will be less than size `size` if the elements don't divide evenly. + */ + def grouped(size: Int): Iterator[Array[A]] = new ArrayOps.GroupedIterator[A](xs, size) + + /** Splits this array into a prefix/suffix pair according to a predicate. + * + * Note: `c span p` is equivalent to (but more efficient than) + * `(c takeWhile p, c dropWhile p)`, provided the evaluation of the + * predicate `p` does not cause any side-effects. + * + * @param p the test predicate + * @return a pair consisting of the longest prefix of this array whose + * elements all satisfy `p`, and the rest of this array. + */ + def span(p: A => Boolean): (Array[A], Array[A]) = { + val i = indexWhere(x => !p(x)) + val idx = if(i < 0) xs.length else i + (slice(0, idx), slice(idx, xs.length)) + } + + /** Splits this array into two at a given position. + * Note: `c splitAt n` is equivalent to `(c take n, c drop n)`. + * + * @param n the position at which to split. + * @return a pair of arrays consisting of the first `n` + * elements of this array, and the other elements. + */ + def splitAt(n: Int): (Array[A], Array[A]) = (take(n), drop(n)) + + /** A pair of, first, all elements that satisfy predicate `p` and, second, all elements that do not. */ + def partition(p: A => Boolean): (Array[A], Array[A]) = { + val res1, res2 = ArrayBuilder.make[A] + var i = 0 + while(i < xs.length) { + val x = xs(i) + (if(p(x)) res1 else res2) += x + i += 1 + } + (res1.result(), res2.result()) + } + + /** Applies a function `f` to each element of the array and returns a pair of arrays: the first one + * made of those values returned by `f` that were wrapped in [[scala.util.Left]], and the second + * one made of those wrapped in [[scala.util.Right]]. + * + * Example: + * {{{ + * val xs = Array(1, "one", 2, "two", 3, "three") partitionMap { + * case i: Int => Left(i) + * case s: String => Right(s) + * } + * // xs == (Array(1, 2, 3), + * // Array(one, two, three)) + * }}} + * + * @tparam A1 the element type of the first resulting collection + * @tparam A2 the element type of the second resulting collection + * @param f the 'split function' mapping the elements of this array to an [[scala.util.Either]] + * + * @return a pair of arrays: the first one made of those values returned by `f` that were wrapped in [[scala.util.Left]], + * and the second one made of those wrapped in [[scala.util.Right]]. */ + def partitionMap[A1: ClassTag, A2: ClassTag](f: A => Either[A1, A2]): (Array[A1], Array[A2]) = { + val res1 = ArrayBuilder.make[A1] + val res2 = ArrayBuilder.make[A2] + var i = 0 + while(i < xs.length) { + f(xs(i)) match { + case Left(x) => res1 += x + case Right(x) => res2 += x + } + i += 1 + } + (res1.result(), res2.result()) + } + + /** Returns a new array with the elements in reversed order. */ + @inline def reverse: Array[A] = { + val len = xs.length + val res = new Array[A](len) + var i = 0 + while(i < len) { + res(len-i-1) = xs(i) + i += 1 + } + res + } + + /** An iterator yielding elements in reversed order. + * + * Note: `xs.reverseIterator` is the same as `xs.reverse.iterator` but implemented more efficiently. + * + * @return an iterator yielding the elements of this array in reversed order + */ + def reverseIterator: Iterator[A] = + ((xs: Any @unchecked) match { + case xs: Array[AnyRef] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Int] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Double] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Long] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Float] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Char] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Byte] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Short] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Boolean] => new ArrayOps.ReverseIterator(xs) + case xs: Array[Unit] => new ArrayOps.ReverseIterator(xs) + case null => throw new NullPointerException + }).asInstanceOf[Iterator[A]] + + /** Selects all elements of this array which satisfy a predicate. + * + * @param p the predicate used to test elements. + * @return a new array consisting of all elements of this array that satisfy the given predicate `p`. + */ + def filter(p: A => Boolean): Array[A] = { + val res = ArrayBuilder.make[A] + var i = 0 + while(i < xs.length) { + val x = xs(i) + if(p(x)) res += x + i += 1 + } + res.result() + } + + /** Selects all elements of this array which do not satisfy a predicate. + * + * @param p the predicate used to test elements. + * @return a new array consisting of all elements of this array that do not satisfy the given predicate `p`. + */ + def filterNot(p: A => Boolean): Array[A] = filter(x => !p(x)) + + /** Sorts this array according to an Ordering. + * + * The sort is stable. That is, elements that are equal (as determined by + * `lt`) appear in the same order in the sorted sequence as in the original. + * + * @see [[scala.math.Ordering]] + * + * @param ord the ordering to be used to compare elements. + * @return an array consisting of the elements of this array + * sorted according to the ordering `ord`. + */ + def sorted[B >: A](implicit ord: Ordering[B]): Array[A] = { + val len = xs.length + def boxed = if(len < ArrayOps.MaxStableSortLength) { + val a = xs.clone() + Sorting.stableSort(a)(ord.asInstanceOf[Ordering[A]]) + a + } else { + val a = Array.copyAs[AnyRef](xs, len)(ClassTag.AnyRef) + Arrays.sort(a, ord.asInstanceOf[Ordering[AnyRef]]) + Array.copyAs[A](a, len) + } + if(len <= 1) xs.clone() + else ((xs: Array[_]) match { + case xs: Array[AnyRef] => + val a = Arrays.copyOf(xs, len); Arrays.sort(a, ord.asInstanceOf[Ordering[AnyRef]]); a + case xs: Array[Int] => + if(ord eq Ordering.Int) { val a = Arrays.copyOf(xs, len); Arrays.sort(a); a } + else boxed + case xs: Array[Long] => + if(ord eq Ordering.Long) { val a = Arrays.copyOf(xs, len); Arrays.sort(a); a } + else boxed + case xs: Array[Char] => + if(ord eq Ordering.Char) { val a = Arrays.copyOf(xs, len); Arrays.sort(a); a } + else boxed + case xs: Array[Byte] => + if(ord eq Ordering.Byte) { val a = Arrays.copyOf(xs, len); Arrays.sort(a); a } + else boxed + case xs: Array[Short] => + if(ord eq Ordering.Short) { val a = Arrays.copyOf(xs, len); Arrays.sort(a); a } + else boxed + case xs: Array[Boolean] => + if(ord eq Ordering.Boolean) { val a = Arrays.copyOf(xs, len); Sorting.stableSort(a); a } + else boxed + case xs => boxed + }).asInstanceOf[Array[A]] + } + + /** Sorts this array according to a comparison function. + * + * The sort is stable. That is, elements that are equal (as determined by + * `lt`) appear in the same order in the sorted sequence as in the original. + * + * @param lt the comparison function which tests whether + * its first argument precedes its second argument in + * the desired ordering. + * @return an array consisting of the elements of this array + * sorted according to the comparison function `lt`. + */ + def sortWith(lt: (A, A) => Boolean): Array[A] = sorted(Ordering.fromLessThan(lt)) + + /** Sorts this array according to the Ordering which results from transforming + * an implicitly given Ordering with a transformation function. + * + * @see [[scala.math.Ordering]] + * @param f the transformation function mapping elements + * to some other domain `B`. + * @param ord the ordering assumed on domain `B`. + * @tparam B the target type of the transformation `f`, and the type where + * the ordering `ord` is defined. + * @return an array consisting of the elements of this array + * sorted according to the ordering where `x < y` if + * `ord.lt(f(x), f(y))`. + */ + def sortBy[B](f: A => B)(implicit ord: Ordering[B]): Array[A] = sorted(ord on f) + + /** Creates a non-strict filter of this array. + * + * Note: the difference between `c filter p` and `c withFilter p` is that + * the former creates a new array, whereas the latter only + * restricts the domain of subsequent `map`, `flatMap`, `foreach`, + * and `withFilter` operations. + * + * @param p the predicate used to test elements. + * @return an object of class `ArrayOps.WithFilter`, which supports + * `map`, `flatMap`, `foreach`, and `withFilter` operations. + * All these operations apply to those elements of this array + * which satisfy the predicate `p`. + */ + def withFilter(p: A => Boolean): ArrayOps.WithFilter[A] = new ArrayOps.WithFilter[A](p, xs) + + /** Finds index of first occurrence of some value in this array after or at some start index. + * + * @param elem the element value to search for. + * @param from the start index + * @return the index `>= from` of the first element of this array that is equal (as determined by `==`) + * to `elem`, or `-1`, if none exists. + */ + def indexOf(elem: A, from: Int = 0): Int = { + var i = from + while(i < xs.length) { + if(elem == xs(i)) return i + i += 1 + } + -1 + } + + /** Finds index of the first element satisfying some predicate after or at some start index. + * + * @param p the predicate used to test elements. + * @param from the start index + * @return the index `>= from` of the first element of this array that satisfies the predicate `p`, + * or `-1`, if none exists. + */ + def indexWhere(@deprecatedName("f", "2.13.3") p: A => Boolean, from: Int = 0): Int = { + var i = from + while(i < xs.length) { + if(p(xs(i))) return i + i += 1 + } + -1 + } + + /** Finds index of last occurrence of some value in this array before or at a given end index. + * + * @param elem the element value to search for. + * @param end the end index. + * @return the index `<= end` of the last element of this array that is equal (as determined by `==`) + * to `elem`, or `-1`, if none exists. + */ + def lastIndexOf(elem: A, end: Int = xs.length - 1): Int = { + var i = min(end, xs.length-1) + while(i >= 0) { + if(elem == xs(i)) return i + i -= 1 + } + -1 + } + + /** Finds index of last element satisfying some predicate before or at given end index. + * + * @param p the predicate used to test elements. + * @return the index `<= end` of the last element of this array that satisfies the predicate `p`, + * or `-1`, if none exists. + */ + def lastIndexWhere(p: A => Boolean, end: Int = xs.length - 1): Int = { + var i = min(end, xs.length-1) + while(i >= 0) { + if(p(xs(i))) return i + i -= 1 + } + -1 + } + + /** Finds the first element of the array satisfying a predicate, if any. + * + * @param p the predicate used to test elements. + * @return an option value containing the first element in the array + * that satisfies `p`, or `None` if none exists. + */ + def find(@deprecatedName("f", "2.13.3") p: A => Boolean): Option[A] = { + val idx = indexWhere(p) + if(idx == -1) None else Some(xs(idx)) + } + + /** Tests whether a predicate holds for at least one element of this array. + * + * @param p the predicate used to test elements. + * @return `true` if the given predicate `p` is satisfied by at least one element of this array, otherwise `false` + */ + def exists(@deprecatedName("f", "2.13.3") p: A => Boolean): Boolean = indexWhere(p) >= 0 + + /** Tests whether a predicate holds for all elements of this array. + * + * @param p the predicate used to test elements. + * @return `true` if this array is empty or the given predicate `p` + * holds for all elements of this array, otherwise `false`. + */ + def forall(@deprecatedName("f", "2.13.3") p: A => Boolean): Boolean = { + var i = 0 + while(i < xs.length) { + if(!p(xs(i))) return false + i += 1 + } + true + } + + /** Applies a binary operator to a start value and all elements of this array, + * going left to right. + * + * @param z the start value. + * @param op the binary operator. + * @tparam B the result type of the binary operator. + * @return the result of inserting `op` between consecutive elements of this array, + * going left to right with the start value `z` on the left: + * {{{ + * op(...op(z, x_1), x_2, ..., x_n) + * }}} + * where `x,,1,,, ..., x,,n,,` are the elements of this array. + * Returns `z` if this array is empty. + */ + def foldLeft[B](z: B)(op: (B, A) => B): B = { + def f[@specialized(Specializable.Everything) T](xs: Array[T], op: (Any, Any) => Any, z: Any): Any = { + val length = xs.length + var v: Any = z + var i = 0 + while(i < length) { + v = op(v, xs(i)) + i += 1 + } + v + } + ((xs: Any @unchecked) match { + case null => throw new NullPointerException // null-check first helps static analysis of instanceOf + case xs: Array[AnyRef] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Int] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Double] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Long] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Float] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Char] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Byte] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Short] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Boolean] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Unit] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + }).asInstanceOf[B] + } + + /** Produces an array containing cumulative results of applying the binary + * operator going left to right. + * + * @param z the start value. + * @param op the binary operator. + * @tparam B the result type of the binary operator. + * @return array with intermediate values. + * + * Example: + * {{{ + * Array(1, 2, 3, 4).scanLeft(0)(_ + _) == Array(0, 1, 3, 6, 10) + * }}} + * + */ + def scanLeft[ B : ClassTag ](z: B)(op: (B, A) => B): Array[B] = { + var v = z + var i = 0 + val res = new Array[B](xs.length + 1) + while(i < xs.length) { + res(i) = v + v = op(v, xs(i)) + i += 1 + } + res(i) = v + res + } + + /** Computes a prefix scan of the elements of the array. + * + * Note: The neutral element `z` may be applied more than once. + * + * @tparam B element type of the resulting array + * @param z neutral element for the operator `op` + * @param op the associative operator for the scan + * + * @return a new array containing the prefix scan of the elements in this array + */ + def scan[B >: A : ClassTag](z: B)(op: (B, B) => B): Array[B] = scanLeft(z)(op) + + /** Produces an array containing cumulative results of applying the binary + * operator going right to left. + * + * @param z the start value. + * @param op the binary operator. + * @tparam B the result type of the binary operator. + * @return array with intermediate values. + * + * Example: + * {{{ + * Array(4, 3, 2, 1).scanRight(0)(_ + _) == Array(10, 6, 3, 1, 0) + * }}} + * + */ + def scanRight[ B : ClassTag ](z: B)(op: (A, B) => B): Array[B] = { + var v = z + var i = xs.length - 1 + val res = new Array[B](xs.length + 1) + res(xs.length) = z + while(i >= 0) { + v = op(xs(i), v) + res(i) = v + i -= 1 + } + res + } + + /** Applies a binary operator to all elements of this array and a start value, + * going right to left. + * + * @param z the start value. + * @param op the binary operator. + * @tparam B the result type of the binary operator. + * @return the result of inserting `op` between consecutive elements of this array, + * going right to left with the start value `z` on the right: + * {{{ + * op(x_1, op(x_2, ... op(x_n, z)...)) + * }}} + * where `x,,1,,, ..., x,,n,,` are the elements of this array. + * Returns `z` if this array is empty. + */ + def foldRight[B](z: B)(op: (A, B) => B): B = { + def f[@specialized(Specializable.Everything) T](xs: Array[T], op: (Any, Any) => Any, z: Any): Any = { + var v = z + var i = xs.length - 1 + while(i >= 0) { + v = op(xs(i), v) + i -= 1 + } + v + } + ((xs: Any @unchecked) match { + case null => throw new NullPointerException + case xs: Array[AnyRef] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Int] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Double] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Long] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Float] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Char] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Byte] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Short] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Boolean] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + case xs: Array[Unit] => f(xs, op.asInstanceOf[(Any, Any) => Any], z) + }).asInstanceOf[B] + + } + + /** Folds the elements of this array using the specified associative binary operator. + * + * @tparam A1 a type parameter for the binary operator, a supertype of `A`. + * @param z a neutral element for the fold operation; may be added to the result + * an arbitrary number of times, and must not change the result (e.g., `Nil` for list concatenation, + * 0 for addition, or 1 for multiplication). + * @param op a binary operator that must be associative. + * @return the result of applying the fold operator `op` between all the elements, or `z` if this array is empty. + */ + def fold[A1 >: A](z: A1)(op: (A1, A1) => A1): A1 = foldLeft(z)(op) + + /** Builds a new array by applying a function to all elements of this array. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned array. + * @return a new array resulting from applying the given function + * `f` to each element of this array and collecting the results. + */ + def map[B](f: A => B)(implicit ct: ClassTag[B]): Array[B] = { + val len = xs.length + val ys = new Array[B](len) + if(len > 0) { + var i = 0 + (xs: Any @unchecked) match { + case xs: Array[AnyRef] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Int] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Double] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Long] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Float] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Char] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Byte] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Short] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Boolean] => while (i < len) { ys(i) = f(xs(i).asInstanceOf[A]); i = i+1 } + } + } + ys + } + + def mapInPlace(f: A => A): Array[A] = { + var i = 0 + while (i < xs.length) { + xs.update(i, f(xs(i))) + i = i + 1 + } + xs + } + + /** Builds a new array by applying a function to all elements of this array + * and using the elements of the resulting collections. + * + * @param f the function to apply to each element. + * @tparam B the element type of the returned array. + * @return a new array resulting from applying the given collection-valued function + * `f` to each element of this array and concatenating the results. + */ + def flatMap[B : ClassTag](f: A => IterableOnce[B]): Array[B] = { + val b = ArrayBuilder.make[B] + var i = 0 + while(i < xs.length) { + b ++= f(xs(i)) + i += 1 + } + b.result() + } + + def flatMap[BS, B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B] = + flatMap[B](x => asIterable(f(x))) + + /** Flattens a two-dimensional array by concatenating all its rows + * into a single array. + * + * @tparam B Type of row elements. + * @param asIterable A function that converts elements of this array to rows - Iterables of type `B`. + * @return An array obtained by concatenating rows of this array. + */ + def flatten[B](implicit asIterable: A => IterableOnce[B], m: ClassTag[B]): Array[B] = { + val b = ArrayBuilder.make[B] + val len = xs.length + var size = 0 + var i = 0 + while(i < len) { + xs(i) match { + case it: IterableOnce[_] => + val k = it.knownSize + if(k > 0) size += k + case a: Array[_] => size += a.length + case _ => + } + i += 1 + } + if(size > 0) b.sizeHint(size) + i = 0 + while(i < len) { + b ++= asIterable(xs(i)) + i += 1 + } + b.result() + } + + /** Builds a new array by applying a partial function to all elements of this array + * on which the function is defined. + * + * @param pf the partial function which filters and maps the array. + * @tparam B the element type of the returned array. + * @return a new array resulting from applying the given partial function + * `pf` to each element on which it is defined and collecting the results. + * The order of the elements is preserved. + */ + def collect[B: ClassTag](pf: PartialFunction[A, B]): Array[B] = { + val fallback: Any => Any = ArrayOps.fallback + val b = ArrayBuilder.make[B] + var i = 0 + while (i < xs.length) { + val v = pf.applyOrElse(xs(i), fallback) + if (v.asInstanceOf[AnyRef] ne fallback) b.addOne(v.asInstanceOf[B]) + i += 1 + } + b.result() + } + + /** Finds the first element of the array for which the given partial function is defined, and applies the + * partial function to it. */ + def collectFirst[B](@deprecatedName("f","2.13.9") pf: PartialFunction[A, B]): Option[B] = { + val fallback: Any => Any = ArrayOps.fallback + var i = 0 + while (i < xs.length) { + val v = pf.applyOrElse(xs(i), fallback) + if (v.asInstanceOf[AnyRef] ne fallback) return Some(v.asInstanceOf[B]) + i += 1 + } + None + } + + /** Returns an array formed from this array and another iterable collection + * by combining corresponding elements in pairs. + * If one of the two collections is longer than the other, its remaining elements are ignored. + * + * @param that The iterable providing the second half of each result pair + * @tparam B the type of the second half of the returned pairs + * @return a new array containing pairs consisting of corresponding elements of this array and `that`. + * The length of the returned array is the minimum of the lengths of this array and `that`. + */ + def zip[B](that: IterableOnce[B]): Array[(A, B)] = { + val b = new ArrayBuilder.ofRef[(A, B)]() + val k = that.knownSize + b.sizeHint(if(k >= 0) min(k, xs.length) else xs.length) + var i = 0 + val it = that.iterator + while(i < xs.length && it.hasNext) { + b += ((xs(i), it.next())) + i += 1 + } + b.result() + } + + /** Analogous to `zip` except that the elements in each collection are not consumed until a strict operation is + * invoked on the returned `LazyZip2` decorator. + * + * Calls to `lazyZip` can be chained to support higher arities (up to 4) without incurring the expense of + * constructing and deconstructing intermediary tuples. + * + * {{{ + * val xs = List(1, 2, 3) + * val res = (xs lazyZip xs lazyZip xs lazyZip xs).map((a, b, c, d) => a + b + c + d) + * // res == List(4, 8, 12) + * }}} + * + * @param that the iterable providing the second element of each eventual pair + * @tparam B the type of the second element in each eventual pair + * @return a decorator `LazyZip2` that allows strict operations to be performed on the lazily evaluated pairs + * or chained calls to `lazyZip`. Implicit conversion to `Iterable[(A, B)]` is also supported. + */ + def lazyZip[B](that: Iterable[B]): LazyZip2[A, B, Array[A]] = new LazyZip2(xs, immutable.ArraySeq.unsafeWrapArray(xs), that) + + /** Returns an array formed from this array and another iterable collection + * by combining corresponding elements in pairs. + * If one of the two collections is shorter than the other, + * placeholder elements are used to extend the shorter collection to the length of the longer. + * + * @param that the iterable providing the second half of each result pair + * @param thisElem the element to be used to fill up the result if this array is shorter than `that`. + * @param thatElem the element to be used to fill up the result if `that` is shorter than this array. + * @return a new array containing pairs consisting of corresponding elements of this array and `that`. + * The length of the returned array is the maximum of the lengths of this array and `that`. + * If this array is shorter than `that`, `thisElem` values are used to pad the result. + * If `that` is shorter than this array, `thatElem` values are used to pad the result. + */ + def zipAll[A1 >: A, B](that: Iterable[B], thisElem: A1, thatElem: B): Array[(A1, B)] = { + val b = new ArrayBuilder.ofRef[(A1, B)]() + val k = that.knownSize + b.sizeHint(max(k, xs.length)) + var i = 0 + val it = that.iterator + while(i < xs.length && it.hasNext) { + b += ((xs(i), it.next())) + i += 1 + } + while(it.hasNext) { + b += ((thisElem, it.next())) + i += 1 + } + while(i < xs.length) { + b += ((xs(i), thatElem)) + i += 1 + } + b.result() + } + + /** Zips this array with its indices. + * + * @return A new array containing pairs consisting of all elements of this array paired with their index. + * Indices start at `0`. + */ + def zipWithIndex: Array[(A, Int)] = { + val b = new Array[(A, Int)](xs.length) + var i = 0 + while(i < xs.length) { + b(i) = ((xs(i), i)) + i += 1 + } + b + } + + /** A copy of this array with an element appended. */ + def appended[B >: A : ClassTag](x: B): Array[B] = { + val dest = Array.copyAs[B](xs, xs.length+1) + dest(xs.length) = x + dest + } + + @`inline` final def :+ [B >: A : ClassTag](x: B): Array[B] = appended(x) + + /** A copy of this array with an element prepended. */ + def prepended[B >: A : ClassTag](x: B): Array[B] = { + val dest = new Array[B](xs.length + 1) + dest(0) = x + Array.copy(xs, 0, dest, 1, xs.length) + dest + } + + @`inline` final def +: [B >: A : ClassTag](x: B): Array[B] = prepended(x) + + /** A copy of this array with all elements of a collection prepended. */ + def prependedAll[B >: A : ClassTag](prefix: IterableOnce[B]): Array[B] = { + val b = ArrayBuilder.make[B] + val k = prefix.knownSize + if(k >= 0) b.sizeHint(k + xs.length) + b.addAll(prefix) + if(k < 0) b.sizeHint(b.length + xs.length) + b.addAll(xs) + b.result() + } + + /** A copy of this array with all elements of an array prepended. */ + def prependedAll[B >: A : ClassTag](prefix: Array[_ <: B]): Array[B] = { + val dest = Array.copyAs[B](prefix, prefix.length+xs.length) + Array.copy(xs, 0, dest, prefix.length, xs.length) + dest + } + + @`inline` final def ++: [B >: A : ClassTag](prefix: IterableOnce[B]): Array[B] = prependedAll(prefix) + + @`inline` final def ++: [B >: A : ClassTag](prefix: Array[_ <: B]): Array[B] = prependedAll(prefix) + + /** A copy of this array with all elements of a collection appended. */ + def appendedAll[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = { + val b = ArrayBuilder.make[B] + val k = suffix.knownSize + if(k >= 0) b.sizeHint(k + xs.length) + b.addAll(xs) + b.addAll(suffix) + b.result() + } + + /** A copy of this array with all elements of an array appended. */ + def appendedAll[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = { + val dest = Array.copyAs[B](xs, xs.length+suffix.length) + Array.copy(suffix, 0, dest, xs.length, suffix.length) + dest + } + + @`inline` final def :++ [B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = appendedAll(suffix) + + @`inline` final def :++ [B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = appendedAll(suffix) + + @`inline` final def concat[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = appendedAll(suffix) + + @`inline` final def concat[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = appendedAll(suffix) + + @`inline` final def ++[B >: A : ClassTag](xs: IterableOnce[B]): Array[B] = appendedAll(xs) + + @`inline` final def ++[B >: A : ClassTag](xs: Array[_ <: B]): Array[B] = appendedAll(xs) + + /** Tests whether this array contains a given value as an element. + * + * @param elem the element to test. + * @return `true` if this array has an element that is equal (as + * determined by `==`) to `elem`, `false` otherwise. + */ + def contains(elem: A): Boolean = exists (_ == elem) + + /** Returns a copy of this array with patched values. + * Patching at negative indices is the same as patching starting at 0. + * Patching at indices at or larger than the length of the original array appends the patch to the end. + * If more values are replaced than actually exist, the excess is ignored. + * + * @param from The start index from which to patch + * @param other The patch values + * @param replaced The number of values in the original array that are replaced by the patch. + */ + def patch[B >: A : ClassTag](from: Int, other: IterableOnce[B], replaced: Int): Array[B] = { + val b = ArrayBuilder.make[B] + val k = other.knownSize + val r = if(replaced < 0) 0 else replaced + if(k >= 0) b.sizeHint(xs.length + k - r) + val chunk1 = if(from > 0) min(from, xs.length) else 0 + if(chunk1 > 0) b.addAll(xs, 0, chunk1) + b ++= other + val remaining = xs.length - chunk1 - r + if(remaining > 0) b.addAll(xs, xs.length - remaining, remaining) + b.result() + } + + /** Converts an array of pairs into an array of first elements and an array of second elements. + * + * @tparam A1 the type of the first half of the element pairs + * @tparam A2 the type of the second half of the element pairs + * @param asPair an implicit conversion which asserts that the element type + * of this Array is a pair. + * @param ct1 a class tag for `A1` type parameter that is required to create an instance + * of `Array[A1]` + * @param ct2 a class tag for `A2` type parameter that is required to create an instance + * of `Array[A2]` + * @return a pair of Arrays, containing, respectively, the first and second half + * of each element pair of this Array. + */ + def unzip[A1, A2](implicit asPair: A => (A1, A2), ct1: ClassTag[A1], ct2: ClassTag[A2]): (Array[A1], Array[A2]) = { + val a1 = new Array[A1](xs.length) + val a2 = new Array[A2](xs.length) + var i = 0 + while (i < xs.length) { + val e = asPair(xs(i)) + a1(i) = e._1 + a2(i) = e._2 + i += 1 + } + (a1, a2) + } + + /** Converts an array of triples into three arrays, one containing the elements from each position of the triple. + * + * @tparam A1 the type of the first of three elements in the triple + * @tparam A2 the type of the second of three elements in the triple + * @tparam A3 the type of the third of three elements in the triple + * @param asTriple an implicit conversion which asserts that the element type + * of this Array is a triple. + * @param ct1 a class tag for T1 type parameter that is required to create an instance + * of Array[T1] + * @param ct2 a class tag for T2 type parameter that is required to create an instance + * of Array[T2] + * @param ct3 a class tag for T3 type parameter that is required to create an instance + * of Array[T3] + * @return a triple of Arrays, containing, respectively, the first, second, and third + * elements from each element triple of this Array. + */ + def unzip3[A1, A2, A3](implicit asTriple: A => (A1, A2, A3), ct1: ClassTag[A1], ct2: ClassTag[A2], + ct3: ClassTag[A3]): (Array[A1], Array[A2], Array[A3]) = { + val a1 = new Array[A1](xs.length) + val a2 = new Array[A2](xs.length) + val a3 = new Array[A3](xs.length) + var i = 0 + while (i < xs.length) { + val e = asTriple(xs(i)) + a1(i) = e._1 + a2(i) = e._2 + a3(i) = e._3 + i += 1 + } + (a1, a2, a3) + } + + /** Transposes a two dimensional array. + * + * @tparam B Type of row elements. + * @param asArray A function that converts elements of this array to rows - arrays of type `B`. + * @return An array obtained by replacing elements of this arrays with rows the represent. + */ + def transpose[B](implicit asArray: A => Array[B]): Array[Array[B]] = { + val aClass = xs.getClass.getComponentType + val bb = new ArrayBuilder.ofRef[Array[B]]()(ClassTag[Array[B]](aClass)) + if (xs.length == 0) bb.result() + else { + def mkRowBuilder() = ArrayBuilder.make[B](ClassTag[B](aClass.getComponentType)) + val bs = new ArrayOps(asArray(xs(0))).map((x: B) => mkRowBuilder()) + for (xs <- this) { + var i = 0 + for (x <- new ArrayOps(asArray(xs))) { + bs(i) += x + i += 1 + } + } + for (b <- new ArrayOps(bs)) bb += b.result() + bb.result() + } + } + + /** Apply `f` to each element for its side effects. + * Note: [U] parameter needed to help scalac's type inference. + */ + def foreach[U](f: A => U): Unit = { + val len = xs.length + var i = 0 + (xs: Any @unchecked) match { + case xs: Array[AnyRef] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Int] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Double] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Long] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Float] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Char] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Byte] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Short] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + case xs: Array[Boolean] => while (i < len) { f(xs(i).asInstanceOf[A]); i = i+1 } + } + } + + /** Selects all the elements of this array ignoring the duplicates. + * + * @return a new array consisting of all the elements of this array without duplicates. + */ + def distinct: Array[A] = distinctBy(identity) + + /** Selects all the elements of this array ignoring the duplicates as determined by `==` after applying + * the transforming function `f`. + * + * @param f The transforming function whose result is used to determine the uniqueness of each element + * @tparam B the type of the elements after being transformed by `f` + * @return a new array consisting of all the elements of this array without duplicates. + */ + def distinctBy[B](f: A => B): Array[A] = + ArrayBuilder.make[A].addAll(iterator.distinctBy(f)).result() + + /** A copy of this array with an element value appended until a given target length is reached. + * + * @param len the target length + * @param elem the padding value + * @tparam B the element type of the returned array. + * @return a new array consisting of + * all elements of this array followed by the minimal number of occurrences of `elem` so + * that the resulting collection has a length of at least `len`. + */ + def padTo[B >: A : ClassTag](len: Int, elem: B): Array[B] = { + var i = xs.length + val newlen = max(i, len) + val dest = Array.copyAs[B](xs, newlen) + while(i < newlen) { + dest(i) = elem + i += 1 + } + dest + } + + /** Produces the range of all indices of this sequence. + * + * @return a `Range` value from `0` to one less than the length of this array. + */ + def indices: Range = Range(0, xs.length) + + /** Partitions this array into a map of arrays according to some discriminator function. + * + * @param f the discriminator function. + * @tparam K the type of keys returned by the discriminator function. + * @return A map from keys to arrays such that the following invariant holds: + * {{{ + * (xs groupBy f)(k) = xs filter (x => f(x) == k) + * }}} + * That is, every key `k` is bound to an array of those elements `x` + * for which `f(x)` equals `k`. + */ + def groupBy[K](f: A => K): immutable.Map[K, Array[A]] = { + val m = mutable.Map.empty[K, ArrayBuilder[A]] + val len = xs.length + var i = 0 + while(i < len) { + val elem = xs(i) + val key = f(elem) + val bldr = m.getOrElseUpdate(key, ArrayBuilder.make[A]) + bldr += elem + i += 1 + } + m.view.mapValues(_.result()).toMap + } + + /** + * Partitions this array into a map of arrays according to a discriminator function `key`. + * Each element in a group is transformed into a value of type `B` using the `value` function. + * + * It is equivalent to `groupBy(key).mapValues(_.map(f))`, but more efficient. + * + * {{{ + * case class User(name: String, age: Int) + * + * def namesByAge(users: Array[User]): Map[Int, Array[String]] = + * users.groupMap(_.age)(_.name) + * }}} + * + * @param key the discriminator function + * @param f the element transformation function + * @tparam K the type of keys returned by the discriminator function + * @tparam B the type of values returned by the transformation function + */ + def groupMap[K, B : ClassTag](key: A => K)(f: A => B): immutable.Map[K, Array[B]] = { + val m = mutable.Map.empty[K, ArrayBuilder[B]] + val len = xs.length + var i = 0 + while(i < len) { + val elem = xs(i) + val k = key(elem) + val bldr = m.getOrElseUpdate(k, ArrayBuilder.make[B]) + bldr += f(elem) + i += 1 + } + m.view.mapValues(_.result()).toMap + } + + @`inline` final def toSeq: immutable.Seq[A] = toIndexedSeq + + def toIndexedSeq: immutable.IndexedSeq[A] = + immutable.ArraySeq.unsafeWrapArray(Array.copyOf(xs, xs.length)) + + /** Copy elements of this array to another array. + * Fills the given array `xs` starting at index 0. + * Copying will stop once either all the elements of this array have been copied, + * or the end of the array is reached. + * + * @param xs the array to fill. + * @tparam B the type of the elements of the array. + */ + def copyToArray[B >: A](xs: Array[B]): Int = copyToArray(xs, 0) + + /** Copy elements of this array to another array. + * Fills the given array `xs` starting at index `start`. + * Copying will stop once either all the elements of this array have been copied, + * or the end of the array is reached. + * + * @param xs the array to fill. + * @param start the starting index within the destination array. + * @tparam B the type of the elements of the array. + */ + def copyToArray[B >: A](xs: Array[B], start: Int): Int = copyToArray(xs, start, Int.MaxValue) + + /** Copy elements of this array to another array. + * Fills the given array `xs` starting at index `start` with at most `len` values. + * Copying will stop once either all the elements of this array have been copied, + * or the end of the array is reached, or `len` elements have been copied. + * + * @param xs the array to fill. + * @param start the starting index within the destination array. + * @param len the maximal number of elements to copy. + * @tparam B the type of the elements of the array. + */ + def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + val copied = IterableOnce.elemsToCopyToArray(this.xs.length, xs.length, start, len) + if (copied > 0) { + Array.copy(this.xs, 0, xs, start, copied) + } + copied + } + + /** Create a copy of this array with the specified element type. */ + def toArray[B >: A: ClassTag]: Array[B] = { + val destination = new Array[B](xs.length) + copyToArray(destination, 0) + destination + } + + /** Counts the number of elements in this array which satisfy a predicate */ + def count(p: A => Boolean): Int = { + var i, res = 0 + val len = xs.length + while(i < len) { + if(p(xs(i))) res += 1 + i += 1 + } + res + } + + // can't use a default arg because we already have another overload with a default arg + /** Tests whether this array starts with the given array. */ + @`inline` def startsWith[B >: A](that: Array[B]): Boolean = startsWith(that, 0) + + /** Tests whether this array contains the given array at a given index. + * + * @param that the array to test + * @param offset the index where the array is searched. + * @return `true` if the array `that` is contained in this array at + * index `offset`, otherwise `false`. + */ + def startsWith[B >: A](that: Array[B], offset: Int): Boolean = { + val safeOffset = offset.max(0) + val thatl = that.length + if(thatl > xs.length-safeOffset) thatl == 0 + else { + var i = 0 + while(i < thatl) { + if(xs(i+safeOffset) != that(i)) return false + i += 1 + } + true + } + } + + /** Tests whether this array ends with the given array. + * + * @param that the array to test + * @return `true` if this array has `that` as a suffix, `false` otherwise. + */ + def endsWith[B >: A](that: Array[B]): Boolean = { + val thatl = that.length + val off = xs.length - thatl + if(off < 0) false + else { + var i = 0 + while(i < thatl) { + if(xs(i+off) != that(i)) return false + i += 1 + } + true + } + } + + /** A copy of this array with one single replaced element. + * @param index the position of the replacement + * @param elem the replacing element + * @return a new array which is a copy of this array with the element at position `index` replaced by `elem`. + * @throws IndexOutOfBoundsException if `index` does not satisfy `0 <= index < length`. + */ + def updated[B >: A : ClassTag](index: Int, elem: B): Array[B] = { + if(index < 0 || index >= xs.length) throw new IndexOutOfBoundsException(s"$index is out of bounds (min 0, max ${xs.length-1})") + val dest = toArray[B] + dest(index) = elem + dest + } + + @`inline` def view: IndexedSeqView[A] = new ArrayOps.ArrayView[A](xs) + + + /* ************************************************************************************************************ + The remaining methods are provided for completeness but they delegate to mutable.ArraySeq implementations which + may not provide the best possible performance. We need them in `ArrayOps` because their return type + mentions `C` (which is `Array[A]` in `StringOps` and `mutable.ArraySeq[A]` in `mutable.ArraySeq`). + ************************************************************************************************************ */ + + + /** Computes the multiset difference between this array and another sequence. + * + * @param that the sequence of elements to remove + * @return a new array which contains all elements of this array + * except some of occurrences of elements that also appear in `that`. + * If an element value `x` appears + * ''n'' times in `that`, then the first ''n'' occurrences of `x` will not form + * part of the result, but any following occurrences will. + */ + def diff[B >: A](that: Seq[B]): Array[A] = mutable.ArraySeq.make(xs).diff(that).toArray[A] + + /** Computes the multiset intersection between this array and another sequence. + * + * @param that the sequence of elements to intersect with. + * @return a new array which contains all elements of this array + * which also appear in `that`. + * If an element value `x` appears + * ''n'' times in `that`, then the first ''n'' occurrences of `x` will be retained + * in the result, but any following occurrences will be omitted. + */ + def intersect[B >: A](that: Seq[B]): Array[A] = mutable.ArraySeq.make(xs).intersect(that).toArray[A] + + /** Groups elements in fixed size blocks by passing a "sliding window" + * over them (as opposed to partitioning them, as is done in grouped.) + * @see [[scala.collection.Iterator]], method `sliding` + * + * @param size the number of elements per group + * @param step the distance between the first elements of successive groups + * @return An iterator producing arrays of size `size`, except the + * last element (which may be the only element) will be truncated + * if there are fewer than `size` elements remaining to be grouped. + */ + def sliding(size: Int, step: Int = 1): Iterator[Array[A]] = mutable.ArraySeq.make(xs).sliding(size, step).map(_.toArray[A]) + + /** Iterates over combinations of elements. + * + * A '''combination''' of length `n` is a sequence of `n` elements selected in order of their first index in this sequence. + * + * For example, `"xyx"` has two combinations of length 2. The `x` is selected first: `"xx"`, `"xy"`. + * The sequence `"yx"` is not returned as a combination because it is subsumed by `"xy"`. + * + * If there is more than one way to generate the same combination, only one will be returned. + * + * For example, the result `"xy"` arbitrarily selected one of the `x` elements. + * + * As a further illustration, `"xyxx"` has three different ways to generate `"xy"` because there are three elements `x` + * to choose from. Moreover, there are three unordered pairs `"xx"` but only one is returned. + * + * It is not specified which of these equal combinations is returned. It is an implementation detail + * that should not be relied on. For example, the combination `"xx"` does not necessarily contain + * the first `x` in this sequence. This behavior is observable if the elements compare equal + * but are not identical. + * + * As a consequence, `"xyx".combinations(3).next()` is `"xxy"`: the combination does not reflect the order + * of the original sequence, but the order in which elements were selected, by "first index"; + * the order of each `x` element is also arbitrary. + * + * @return An Iterator which traverses the n-element combinations of this array + * @example {{{ + * Array('a', 'b', 'b', 'b', 'c').combinations(2).map(runtime.ScalaRunTime.stringOf).foreach(println) + * // Array(a, b) + * // Array(a, c) + * // Array(b, b) + * // Array(b, c) + * Array('b', 'a', 'b').combinations(2).map(runtime.ScalaRunTime.stringOf).foreach(println) + * // Array(b, b) + * // Array(b, a) + * }}} + */ + def combinations(n: Int): Iterator[Array[A]] = mutable.ArraySeq.make(xs).combinations(n).map(_.toArray[A]) + + /** Iterates over distinct permutations of elements. + * + * @return An Iterator which traverses the distinct permutations of this array. + * @example {{{ + * Array('a', 'b', 'b').permutations.map(runtime.ScalaRunTime.stringOf).foreach(println) + * // Array(a, b, b) + * // Array(b, a, b) + * // Array(b, b, a) + * }}} + */ + def permutations: Iterator[Array[A]] = mutable.ArraySeq.make(xs).permutations.map(_.toArray[A]) + + // we have another overload here, so we need to duplicate this method + /** Tests whether this array contains the given sequence at a given index. + * + * @param that the sequence to test + * @param offset the index where the sequence is searched. + * @return `true` if the sequence `that` is contained in this array at + * index `offset`, otherwise `false`. + */ + def startsWith[B >: A](that: IterableOnce[B], offset: Int = 0): Boolean = mutable.ArraySeq.make(xs).startsWith(that, offset) + + // we have another overload here, so we need to duplicate this method + /** Tests whether this array ends with the given sequence. + * + * @param that the sequence to test + * @return `true` if this array has `that` as a suffix, `false` otherwise. + */ + def endsWith[B >: A](that: Iterable[B]): Boolean = mutable.ArraySeq.make(xs).endsWith(that) +} From 7273c4dc73ad86a8bd4a044c0828fa7c61d26a4b Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 10:37:22 +0100 Subject: [PATCH 39/89] Don't flag wildcard array arguments for not being sealed --- .../src/dotty/tools/dotc/cc/CheckCaptures.scala | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index 3e246c754feb..9d56c93bfaf5 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -21,7 +21,7 @@ import Recheck.* import scala.collection.mutable import CaptureSet.{withCaptureSetsExplained, IdempotentCaptRefMap, CompareResult} import StdNames.nme -import NameKinds.DefaultGetterName +import NameKinds.{DefaultGetterName, WildcardParamName} import reporting.trace /** The capture checker */ @@ -1318,7 +1318,9 @@ class CheckCaptures extends Recheck, SymTransformer: def traverse(t: Type): Unit = t match case AppliedType(tycon, arg :: Nil) if tycon.typeSymbol == defn.ArrayClass => - if !(pos.span.isSynthetic && ctx.reporter.errorsReported) then + if !(pos.span.isSynthetic && ctx.reporter.errorsReported) + && !arg.typeSymbol.name.is(WildcardParamName) + then CheckCaptures.disallowRootCapabilitiesIn(arg, NoSymbol, "Array", "have element type", "Since arrays are mutable, they have to be treated like variables,\nso their element type must be sealed.", @@ -1341,10 +1343,11 @@ class CheckCaptures extends Recheck, SymTransformer: val lctx = tree match case _: DefTree | _: TypeDef if tree.symbol.exists => ctx.withOwner(tree.symbol) case _ => ctx - traverseChildren(tree)(using lctx) - check(tree) + trace(i"post check $tree"): + traverseChildren(tree)(using lctx) + check(tree) def check(tree: Tree)(using Context) = tree match - case t @ TypeApply(fun, args) => + case TypeApply(fun, args) => fun.knownType.widen match case tl: PolyType => val normArgs = args.lazyZip(tl.paramInfos).map: (arg, bounds) => From b67422ed2775984a6dd3a653cc447a7a9a7bed88 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 11:36:27 +0100 Subject: [PATCH 40/89] Fix isPureClass test --- compiler/src/dotty/tools/dotc/cc/CaptureOps.scala | 6 +++++- .../captures/exception-definitions.check | 8 ++++---- tests/neg-custom-args/captures/leaked-curried.check | 11 ++++------- tests/neg-custom-args/captures/leaked-curried.scala | 4 ++-- .../stdlib/collection/mutable/ArraySeq.scala | 3 ++- 5 files changed, 17 insertions(+), 15 deletions(-) diff --git a/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala b/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala index 0fe79da30ca5..40e94ebde5dd 100644 --- a/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala +++ b/compiler/src/dotty/tools/dotc/cc/CaptureOps.scala @@ -231,7 +231,11 @@ extension (cls: ClassSymbol) && bc.givenSelfType.dealiasKeepAnnots.match case CapturingType(_, refs) => refs.isAlwaysEmpty case RetainingType(_, refs) => refs.isEmpty - case selfType => selfType.exists && selfType.captureSet.isAlwaysEmpty + case selfType => + isCaptureChecking // At Setup we have not processed self types yet, so + // unless a self type is explicitly given, we can't tell + // and err on the side of impure. + && selfType.exists && selfType.captureSet.isAlwaysEmpty extension (sym: Symbol) diff --git a/tests/neg-custom-args/captures/exception-definitions.check b/tests/neg-custom-args/captures/exception-definitions.check index 16d623e64f7c..4b1fe0273f52 100644 --- a/tests/neg-custom-args/captures/exception-definitions.check +++ b/tests/neg-custom-args/captures/exception-definitions.check @@ -6,8 +6,8 @@ -- Error: tests/neg-custom-args/captures/exception-definitions.scala:7:12 ---------------------------------------------- 7 | val x = c // error | ^ - |(c : Any^) cannot be referenced here; it is not included in the allowed capture set {} of pure base class class Throwable --- Error: tests/neg-custom-args/captures/exception-definitions.scala:8:8 ----------------------------------------------- + |(c : Any^) cannot be referenced here; it is not included in the allowed capture set {} of the self type of class Err2 +-- Error: tests/neg-custom-args/captures/exception-definitions.scala:8:13 ---------------------------------------------- 8 | class Err3(c: Any^) extends Exception // error - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - | reference (Err3.this.c : Any^) is not included in the allowed capture set {} of pure base class class Throwable + | ^ + | reference (Err3.this.c : Any^) is not included in the allowed capture set {} of the self type of class Err3 diff --git a/tests/neg-custom-args/captures/leaked-curried.check b/tests/neg-custom-args/captures/leaked-curried.check index c23d1516acf5..3f0a9800a4ec 100644 --- a/tests/neg-custom-args/captures/leaked-curried.check +++ b/tests/neg-custom-args/captures/leaked-curried.check @@ -2,10 +2,7 @@ 14 | () => () => io // error | ^^ |(io : Cap^) cannot be referenced here; it is not included in the allowed capture set {} of the self type of class Fuzz --- [E058] Type Mismatch Error: tests/neg-custom-args/captures/leaked-curried.scala:15:10 ------------------------------- -15 | class Foo extends Box, Pure: // error - | ^ - | illegal inheritance: self type Foo^{io} of class Foo does not conform to self type Pure - | of parent trait Pure - | - | longer explanation available when compiling with `-explain` +-- Error: tests/neg-custom-args/captures/leaked-curried.scala:17:20 ---------------------------------------------------- +17 | () => () => io // error + | ^^ + |(io : Cap^) cannot be referenced here; it is not included in the allowed capture set {} of the self type of class Foo diff --git a/tests/neg-custom-args/captures/leaked-curried.scala b/tests/neg-custom-args/captures/leaked-curried.scala index a7c48219b450..f9238259e065 100644 --- a/tests/neg-custom-args/captures/leaked-curried.scala +++ b/tests/neg-custom-args/captures/leaked-curried.scala @@ -12,8 +12,8 @@ def main(): Unit = self => val get: () ->{} () ->{io} Cap^ = () => () => io // error - class Foo extends Box, Pure: // error + class Foo extends Box, Pure: val get: () ->{} () ->{io} Cap^ = - () => () => io + () => () => io // error new Foo val bad = leaked.get()().use() // using a leaked capability diff --git a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala index 1c41f68bc8bb..bd3a208a94c0 100644 --- a/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala +++ b/tests/pos-special/stdlib/collection/mutable/ArraySeq.scala @@ -41,7 +41,8 @@ sealed abstract class ArraySeq[sealed T] with IndexedSeq[T] with IndexedSeqOps[T, ArraySeq, ArraySeq[T]] with StrictOptimizedSeqOps[T, ArraySeq, ArraySeq[T]] - with Serializable { + with Serializable + with Pure { override def iterableFactory: scala.collection.SeqFactory[ArraySeq] = ArraySeq.untagged From c64c057de60201f6245e59d52815e78c38cbd256 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 15:19:47 +0100 Subject: [PATCH 41/89] Make sealed an annotation --- .../src/dotty/tools/dotc/typer/Namer.scala | 9 +- tests/neg/class-mods.scala | 2 +- .../captures/sealed-value-class.scala | 3 + .../stdlib/collection/ArrayOps.scala | 113 +++++++++--------- 4 files changed, 69 insertions(+), 58 deletions(-) create mode 100644 tests/pos-custom-args/captures/sealed-value-class.scala diff --git a/compiler/src/dotty/tools/dotc/typer/Namer.scala b/compiler/src/dotty/tools/dotc/typer/Namer.scala index 7ef552e3661c..5361f37c2a76 100644 --- a/compiler/src/dotty/tools/dotc/typer/Namer.scala +++ b/compiler/src/dotty/tools/dotc/typer/Namer.scala @@ -1042,7 +1042,14 @@ class Namer { typer: Typer => tp val rhs1 = typedAheadType(rhs) - val rhsBodyType: TypeBounds = addVariances(rhs1.tpe).toBounds + val rhsBodyType: TypeBounds = + val bounds = addVariances(rhs1.tpe).toBounds + if sym.is(Sealed) then + sym.resetFlag(Sealed) + bounds.derivedTypeBounds(bounds.lo, + AnnotatedType(bounds.hi, Annotation(defn.Caps_SealedAnnot, rhs1.span))) + else bounds + val unsafeInfo = if (isDerived) rhsBodyType else abstracted(rhsBodyType) def opaqueToBounds(info: Type): Type = diff --git a/tests/neg/class-mods.scala b/tests/neg/class-mods.scala index 60e9fb279364..cf4348ad42d7 100644 --- a/tests/neg/class-mods.scala +++ b/tests/neg/class-mods.scala @@ -2,7 +2,7 @@ open final class Foo1 // error sealed open class Foo2 // error open type T1 // error -sealed type T2 // error +type T2 // ok abstract type T3 // error abstract open type T4 // error diff --git a/tests/pos-custom-args/captures/sealed-value-class.scala b/tests/pos-custom-args/captures/sealed-value-class.scala new file mode 100644 index 000000000000..b5f25bf2d203 --- /dev/null +++ b/tests/pos-custom-args/captures/sealed-value-class.scala @@ -0,0 +1,3 @@ +class Ops[sealed A](xs: Array[A]) extends AnyVal: + + def f(p: A => Boolean): Array[A] = xs diff --git a/tests/pos-special/stdlib/collection/ArrayOps.scala b/tests/pos-special/stdlib/collection/ArrayOps.scala index 485427886625..13f3bd0d5ed2 100644 --- a/tests/pos-special/stdlib/collection/ArrayOps.scala +++ b/tests/pos-special/stdlib/collection/ArrayOps.scala @@ -15,6 +15,7 @@ package collection import java.lang.Math.{max, min} import java.util.Arrays +import language.experimental.captureChecking import scala.Predef.{ // unimport all array-related implicit conversions to avoid triggering them accidentally genericArrayOps => _, @@ -53,14 +54,14 @@ import scala.util.Sorting object ArrayOps { @SerialVersionUID(3L) - private class ArrayView[A](xs: Array[A]) extends AbstractIndexedSeqView[A] { + private class ArrayView[sealed A](xs: Array[A]) extends AbstractIndexedSeqView[A] { def length = xs.length def apply(n: Int) = xs(n) override def toString: String = immutable.ArraySeq.unsafeWrapArray(xs).mkString("ArrayView(", ", ", ")") } /** A lazy filtered array. No filtering is applied until one of `foreach`, `map` or `flatMap` is called. */ - class WithFilter[A](p: A => Boolean, xs: Array[A]) { + class WithFilter[sealed A](p: A => Boolean, xs: Array[A]) { /** Apply `f` to each element for its side effects. * Note: [U] parameter needed to help scalac's type inference. @@ -82,7 +83,7 @@ object ArrayOps { * @return a new array resulting from applying the given function * `f` to each element of this array and collecting the results. */ - def map[B: ClassTag](f: A => B): Array[B] = { + def map[sealed B: ClassTag](f: A => B): Array[B] = { val b = ArrayBuilder.make[B] var i = 0 while (i < xs.length) { @@ -101,7 +102,7 @@ object ArrayOps { * @return a new array resulting from applying the given collection-valued function * `f` to each element of this array and concatenating the results. */ - def flatMap[B: ClassTag](f: A => IterableOnce[B]): Array[B] = { + def flatMap[sealed B: ClassTag](f: A => IterableOnce[B]): Array[B] = { val b = ArrayBuilder.make[B] var i = 0 while(i < xs.length) { @@ -112,15 +113,15 @@ object ArrayOps { b.result() } - def flatMap[BS, B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B] = + def flatMap[BS, sealed B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B] = flatMap[B](x => asIterable(f(x))) /** Creates a new non-strict filter which combines this filter with the given predicate. */ - def withFilter(q: A => Boolean): WithFilter[A] = new WithFilter[A](a => p(a) && q(a), xs) + def withFilter(q: A => Boolean): WithFilter[A]^{this, q} = new WithFilter[A](a => p(a) && q(a), xs) } @SerialVersionUID(3L) - private[collection] final class ArrayIterator[@specialized(Specializable.Everything) A](xs: Array[A]) extends AbstractIterator[A] with Serializable { + private[collection] final class ArrayIterator[@specialized(Specializable.Everything) sealed A](xs: Array[A]) extends AbstractIterator[A] with Serializable { private[this] var pos = 0 private[this] val len = xs.length override def knownSize: Int = len - pos @@ -143,7 +144,7 @@ object ArrayOps { } @SerialVersionUID(3L) - private final class ReverseIterator[@specialized(Specializable.Everything) A](xs: Array[A]) extends AbstractIterator[A] with Serializable { + private final class ReverseIterator[@specialized(Specializable.Everything) sealed A](xs: Array[A]) extends AbstractIterator[A] with Serializable { private[this] var pos = xs.length-1 def hasNext: Boolean = pos >= 0 def next(): A = { @@ -160,7 +161,7 @@ object ArrayOps { } @SerialVersionUID(3L) - private final class GroupedIterator[A](xs: Array[A], groupSize: Int) extends AbstractIterator[Array[A]] with Serializable { + private final class GroupedIterator[sealed A](xs: Array[A], groupSize: Int) extends AbstractIterator[Array[A]] with Serializable { private[this] var pos = 0 def hasNext: Boolean = pos < xs.length def next(): Array[A] = { @@ -196,7 +197,7 @@ object ArrayOps { * * @tparam A type of the elements contained in this array. */ -final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { +final class ArrayOps[sealed A](private val xs: Array[A]) /*extends AnyVal*/ { @`inline` private[this] implicit def elemTag: ClassTag[A] = ClassTag(xs.getClass.getComponentType) @@ -366,7 +367,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { def inits: Iterator[Array[A]] = iterateUntilEmpty(xs => new ArrayOps(xs).init) // A helper for tails and inits. - private[this] def iterateUntilEmpty(f: Array[A] => Array[A]): Iterator[Array[A]] = + private[this] def iterateUntilEmpty(f: Array[A] => Array[A]): Iterator[Array[A]]^{f} = Iterator.iterate(xs)(f).takeWhile(x => x.length != 0) ++ Iterator.single(Array.empty[A]) /** An array containing the first `n` elements of this array. */ @@ -504,7 +505,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * * @return a pair of arrays: the first one made of those values returned by `f` that were wrapped in [[scala.util.Left]], * and the second one made of those wrapped in [[scala.util.Right]]. */ - def partitionMap[A1: ClassTag, A2: ClassTag](f: A => Either[A1, A2]): (Array[A1], Array[A2]) = { + def partitionMap[sealed A1: ClassTag, sealed A2: ClassTag](f: A => Either[A1, A2]): (Array[A1], Array[A2]) = { val res1 = ArrayBuilder.make[A1] val res2 = ArrayBuilder.make[A2] var i = 0 @@ -663,7 +664,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * All these operations apply to those elements of this array * which satisfy the predicate `p`. */ - def withFilter(p: A => Boolean): ArrayOps.WithFilter[A] = new ArrayOps.WithFilter[A](p, xs) + def withFilter(p: A => Boolean): ArrayOps.WithFilter[A]^{p} = new ArrayOps.WithFilter[A](p, xs) /** Finds index of first occurrence of some value in this array after or at some start index. * @@ -776,7 +777,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * Returns `z` if this array is empty. */ def foldLeft[B](z: B)(op: (B, A) => B): B = { - def f[@specialized(Specializable.Everything) T](xs: Array[T], op: (Any, Any) => Any, z: Any): Any = { + def f[@specialized(Specializable.Everything) sealed T](xs: Array[T], op: (Any, Any) => Any, z: Any): Any = { val length = xs.length var v: Any = z var i = 0 @@ -815,7 +816,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * }}} * */ - def scanLeft[ B : ClassTag ](z: B)(op: (B, A) => B): Array[B] = { + def scanLeft[sealed B : ClassTag](z: B)(op: (B, A) => B): Array[B] = { var v = z var i = 0 val res = new Array[B](xs.length + 1) @@ -838,7 +839,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * * @return a new array containing the prefix scan of the elements in this array */ - def scan[B >: A : ClassTag](z: B)(op: (B, B) => B): Array[B] = scanLeft(z)(op) + def scan[sealed B >: A : ClassTag](z: B)(op: (B, B) => B): Array[B] = scanLeft(z)(op) /** Produces an array containing cumulative results of applying the binary * operator going right to left. @@ -854,7 +855,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * }}} * */ - def scanRight[ B : ClassTag ](z: B)(op: (A, B) => B): Array[B] = { + def scanRight[sealed B : ClassTag](z: B)(op: (A, B) => B): Array[B] = { var v = z var i = xs.length - 1 val res = new Array[B](xs.length + 1) @@ -882,7 +883,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * Returns `z` if this array is empty. */ def foldRight[B](z: B)(op: (A, B) => B): B = { - def f[@specialized(Specializable.Everything) T](xs: Array[T], op: (Any, Any) => Any, z: Any): Any = { + def f[@specialized(Specializable.Everything) sealed T](xs: Array[T], op: (Any, Any) => Any, z: Any): Any = { var v = z var i = xs.length - 1 while(i >= 0) { @@ -925,7 +926,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return a new array resulting from applying the given function * `f` to each element of this array and collecting the results. */ - def map[B](f: A => B)(implicit ct: ClassTag[B]): Array[B] = { + def map[sealed B](f: A => B)(implicit ct: ClassTag[B]): Array[B] = { val len = xs.length val ys = new Array[B](len) if(len > 0) { @@ -962,7 +963,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return a new array resulting from applying the given collection-valued function * `f` to each element of this array and concatenating the results. */ - def flatMap[B : ClassTag](f: A => IterableOnce[B]): Array[B] = { + def flatMap[sealed B : ClassTag](f: A => IterableOnce[B]): Array[B] = { val b = ArrayBuilder.make[B] var i = 0 while(i < xs.length) { @@ -972,7 +973,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { b.result() } - def flatMap[BS, B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B] = + def flatMap[BS, sealed B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B] = flatMap[B](x => asIterable(f(x))) /** Flattens a two-dimensional array by concatenating all its rows @@ -982,7 +983,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param asIterable A function that converts elements of this array to rows - Iterables of type `B`. * @return An array obtained by concatenating rows of this array. */ - def flatten[B](implicit asIterable: A => IterableOnce[B], m: ClassTag[B]): Array[B] = { + def flatten[sealed B](implicit asIterable: A => IterableOnce[B], m: ClassTag[B]): Array[B] = { val b = ArrayBuilder.make[B] val len = xs.length var size = 0 @@ -1015,7 +1016,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * `pf` to each element on which it is defined and collecting the results. * The order of the elements is preserved. */ - def collect[B: ClassTag](pf: PartialFunction[A, B]): Array[B] = { + def collect[sealed B: ClassTag](pf: PartialFunction[A, B]): Array[B] = { val fallback: Any => Any = ArrayOps.fallback val b = ArrayBuilder.make[B] var i = 0 @@ -1049,7 +1050,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return a new array containing pairs consisting of corresponding elements of this array and `that`. * The length of the returned array is the minimum of the lengths of this array and `that`. */ - def zip[B](that: IterableOnce[B]): Array[(A, B)] = { + def zip[sealed B](that: IterableOnce[B]): Array[(A, B)] = { val b = new ArrayBuilder.ofRef[(A, B)]() val k = that.knownSize b.sizeHint(if(k >= 0) min(k, xs.length) else xs.length) @@ -1094,7 +1095,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * If this array is shorter than `that`, `thisElem` values are used to pad the result. * If `that` is shorter than this array, `thatElem` values are used to pad the result. */ - def zipAll[A1 >: A, B](that: Iterable[B], thisElem: A1, thatElem: B): Array[(A1, B)] = { + def zipAll[sealed A1 >: A, sealed B](that: Iterable[B], thisElem: A1, thatElem: B): Array[(A1, B)] = { val b = new ArrayBuilder.ofRef[(A1, B)]() val k = that.knownSize b.sizeHint(max(k, xs.length)) @@ -1131,26 +1132,26 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { } /** A copy of this array with an element appended. */ - def appended[B >: A : ClassTag](x: B): Array[B] = { + def appended[sealed B >: A : ClassTag](x: B): Array[B] = { val dest = Array.copyAs[B](xs, xs.length+1) dest(xs.length) = x dest } - @`inline` final def :+ [B >: A : ClassTag](x: B): Array[B] = appended(x) + @`inline` final def :+ [sealed B >: A : ClassTag](x: B): Array[B] = appended(x) /** A copy of this array with an element prepended. */ - def prepended[B >: A : ClassTag](x: B): Array[B] = { + def prepended[sealed B >: A : ClassTag](x: B): Array[B] = { val dest = new Array[B](xs.length + 1) dest(0) = x Array.copy(xs, 0, dest, 1, xs.length) dest } - @`inline` final def +: [B >: A : ClassTag](x: B): Array[B] = prepended(x) + @`inline` final def +: [sealed B >: A : ClassTag](x: B): Array[B] = prepended(x) /** A copy of this array with all elements of a collection prepended. */ - def prependedAll[B >: A : ClassTag](prefix: IterableOnce[B]): Array[B] = { + def prependedAll[sealed B >: A : ClassTag](prefix: IterableOnce[B]): Array[B] = { val b = ArrayBuilder.make[B] val k = prefix.knownSize if(k >= 0) b.sizeHint(k + xs.length) @@ -1161,18 +1162,18 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { } /** A copy of this array with all elements of an array prepended. */ - def prependedAll[B >: A : ClassTag](prefix: Array[_ <: B]): Array[B] = { + def prependedAll[sealed B >: A : ClassTag](prefix: Array[_ <: B]): Array[B] = { val dest = Array.copyAs[B](prefix, prefix.length+xs.length) Array.copy(xs, 0, dest, prefix.length, xs.length) dest } - @`inline` final def ++: [B >: A : ClassTag](prefix: IterableOnce[B]): Array[B] = prependedAll(prefix) + @`inline` final def ++: [sealed B >: A : ClassTag](prefix: IterableOnce[B]): Array[B] = prependedAll(prefix) - @`inline` final def ++: [B >: A : ClassTag](prefix: Array[_ <: B]): Array[B] = prependedAll(prefix) + @`inline` final def ++: [sealed B >: A : ClassTag](prefix: Array[_ <: B]): Array[B] = prependedAll(prefix) /** A copy of this array with all elements of a collection appended. */ - def appendedAll[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = { + def appendedAll[sealed B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = { val b = ArrayBuilder.make[B] val k = suffix.knownSize if(k >= 0) b.sizeHint(k + xs.length) @@ -1182,23 +1183,23 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { } /** A copy of this array with all elements of an array appended. */ - def appendedAll[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = { + def appendedAll[sealed B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = { val dest = Array.copyAs[B](xs, xs.length+suffix.length) Array.copy(suffix, 0, dest, xs.length, suffix.length) dest } - @`inline` final def :++ [B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = appendedAll(suffix) + @`inline` final def :++ [sealed B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = appendedAll(suffix) - @`inline` final def :++ [B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = appendedAll(suffix) + @`inline` final def :++ [sealed B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = appendedAll(suffix) - @`inline` final def concat[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = appendedAll(suffix) + @`inline` final def concat[sealed B >: A : ClassTag](suffix: IterableOnce[B]): Array[B] = appendedAll(suffix) - @`inline` final def concat[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = appendedAll(suffix) + @`inline` final def concat[sealed B >: A : ClassTag](suffix: Array[_ <: B]): Array[B] = appendedAll(suffix) - @`inline` final def ++[B >: A : ClassTag](xs: IterableOnce[B]): Array[B] = appendedAll(xs) + @`inline` final def ++[sealed B >: A : ClassTag](xs: IterableOnce[B]): Array[B] = appendedAll(xs) - @`inline` final def ++[B >: A : ClassTag](xs: Array[_ <: B]): Array[B] = appendedAll(xs) + @`inline` final def ++[sealed B >: A : ClassTag](xs: Array[_ <: B]): Array[B] = appendedAll(xs) /** Tests whether this array contains a given value as an element. * @@ -1217,7 +1218,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param other The patch values * @param replaced The number of values in the original array that are replaced by the patch. */ - def patch[B >: A : ClassTag](from: Int, other: IterableOnce[B], replaced: Int): Array[B] = { + def patch[sealed B >: A : ClassTag](from: Int, other: IterableOnce[B], replaced: Int): Array[B] = { val b = ArrayBuilder.make[B] val k = other.knownSize val r = if(replaced < 0) 0 else replaced @@ -1243,7 +1244,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return a pair of Arrays, containing, respectively, the first and second half * of each element pair of this Array. */ - def unzip[A1, A2](implicit asPair: A => (A1, A2), ct1: ClassTag[A1], ct2: ClassTag[A2]): (Array[A1], Array[A2]) = { + def unzip[sealed A1, sealed A2](implicit asPair: A => (A1, A2), ct1: ClassTag[A1], ct2: ClassTag[A2]): (Array[A1], Array[A2]) = { val a1 = new Array[A1](xs.length) val a2 = new Array[A2](xs.length) var i = 0 @@ -1272,7 +1273,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return a triple of Arrays, containing, respectively, the first, second, and third * elements from each element triple of this Array. */ - def unzip3[A1, A2, A3](implicit asTriple: A => (A1, A2, A3), ct1: ClassTag[A1], ct2: ClassTag[A2], + def unzip3[sealed A1, sealed A2, sealed A3](implicit asTriple: A => (A1, A2, A3), ct1: ClassTag[A1], ct2: ClassTag[A2], ct3: ClassTag[A3]): (Array[A1], Array[A2], Array[A3]) = { val a1 = new Array[A1](xs.length) val a2 = new Array[A2](xs.length) @@ -1294,7 +1295,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param asArray A function that converts elements of this array to rows - arrays of type `B`. * @return An array obtained by replacing elements of this arrays with rows the represent. */ - def transpose[B](implicit asArray: A => Array[B]): Array[Array[B]] = { + def transpose[sealed B](implicit asArray: A => Array[B]): Array[Array[B]] = { val aClass = xs.getClass.getComponentType val bb = new ArrayBuilder.ofRef[Array[B]]()(ClassTag[Array[B]](aClass)) if (xs.length == 0) bb.result() @@ -1345,7 +1346,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @tparam B the type of the elements after being transformed by `f` * @return a new array consisting of all the elements of this array without duplicates. */ - def distinctBy[B](f: A => B): Array[A] = + def distinctBy[B](f: A -> B): Array[A] = ArrayBuilder.make[A].addAll(iterator.distinctBy(f)).result() /** A copy of this array with an element value appended until a given target length is reached. @@ -1357,7 +1358,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * all elements of this array followed by the minimal number of occurrences of `elem` so * that the resulting collection has a length of at least `len`. */ - def padTo[B >: A : ClassTag](len: Int, elem: B): Array[B] = { + def padTo[sealed B >: A : ClassTag](len: Int, elem: B): Array[B] = { var i = xs.length val newlen = max(i, len) val dest = Array.copyAs[B](xs, newlen) @@ -1417,7 +1418,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @tparam K the type of keys returned by the discriminator function * @tparam B the type of values returned by the transformation function */ - def groupMap[K, B : ClassTag](key: A => K)(f: A => B): immutable.Map[K, Array[B]] = { + def groupMap[K, sealed B : ClassTag](key: A => K)(f: A => B): immutable.Map[K, Array[B]] = { val m = mutable.Map.empty[K, ArrayBuilder[B]] val len = xs.length var i = 0 @@ -1444,7 +1445,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param xs the array to fill. * @tparam B the type of the elements of the array. */ - def copyToArray[B >: A](xs: Array[B]): Int = copyToArray(xs, 0) + def copyToArray[sealed B >: A](xs: Array[B]): Int = copyToArray(xs, 0) /** Copy elements of this array to another array. * Fills the given array `xs` starting at index `start`. @@ -1455,7 +1456,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param start the starting index within the destination array. * @tparam B the type of the elements of the array. */ - def copyToArray[B >: A](xs: Array[B], start: Int): Int = copyToArray(xs, start, Int.MaxValue) + def copyToArray[sealed B >: A](xs: Array[B], start: Int): Int = copyToArray(xs, start, Int.MaxValue) /** Copy elements of this array to another array. * Fills the given array `xs` starting at index `start` with at most `len` values. @@ -1467,7 +1468,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param len the maximal number of elements to copy. * @tparam B the type of the elements of the array. */ - def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int = { + def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = { val copied = IterableOnce.elemsToCopyToArray(this.xs.length, xs.length, start, len) if (copied > 0) { Array.copy(this.xs, 0, xs, start, copied) @@ -1476,7 +1477,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { } /** Create a copy of this array with the specified element type. */ - def toArray[B >: A: ClassTag]: Array[B] = { + def toArray[sealed B >: A: ClassTag]: Array[B] = { val destination = new Array[B](xs.length) copyToArray(destination, 0) destination @@ -1495,7 +1496,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { // can't use a default arg because we already have another overload with a default arg /** Tests whether this array starts with the given array. */ - @`inline` def startsWith[B >: A](that: Array[B]): Boolean = startsWith(that, 0) + @`inline` def startsWith[sealed B >: A](that: Array[B]): Boolean = startsWith(that, 0) /** Tests whether this array contains the given array at a given index. * @@ -1504,7 +1505,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return `true` if the array `that` is contained in this array at * index `offset`, otherwise `false`. */ - def startsWith[B >: A](that: Array[B], offset: Int): Boolean = { + def startsWith[sealed B >: A](that: Array[B], offset: Int): Boolean = { val safeOffset = offset.max(0) val thatl = that.length if(thatl > xs.length-safeOffset) thatl == 0 @@ -1523,7 +1524,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @param that the array to test * @return `true` if this array has `that` as a suffix, `false` otherwise. */ - def endsWith[B >: A](that: Array[B]): Boolean = { + def endsWith[sealed B >: A](that: Array[B]): Boolean = { val thatl = that.length val off = xs.length - thatl if(off < 0) false @@ -1543,7 +1544,7 @@ final class ArrayOps[A](private val xs: Array[A]) extends AnyVal { * @return a new array which is a copy of this array with the element at position `index` replaced by `elem`. * @throws IndexOutOfBoundsException if `index` does not satisfy `0 <= index < length`. */ - def updated[B >: A : ClassTag](index: Int, elem: B): Array[B] = { + def updated[sealed B >: A : ClassTag](index: Int, elem: B): Array[B] = { if(index < 0 || index >= xs.length) throw new IndexOutOfBoundsException(s"$index is out of bounds (min 0, max ${xs.length-1})") val dest = toArray[B] dest(index) = elem From 2083af3e08f478f599847769d746761464635cb0 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 15:45:36 +0100 Subject: [PATCH 42/89] Make ArrayOps capture checked --- tests/pos-special/stdlib/collection/ArrayOps.scala | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tests/pos-special/stdlib/collection/ArrayOps.scala b/tests/pos-special/stdlib/collection/ArrayOps.scala index 13f3bd0d5ed2..a52fd0dbd162 100644 --- a/tests/pos-special/stdlib/collection/ArrayOps.scala +++ b/tests/pos-special/stdlib/collection/ArrayOps.scala @@ -197,7 +197,7 @@ object ArrayOps { * * @tparam A type of the elements contained in this array. */ -final class ArrayOps[sealed A](private val xs: Array[A]) /*extends AnyVal*/ { +final class ArrayOps[sealed A](private val xs: Array[A]) extends AnyVal { @`inline` private[this] implicit def elemTag: ClassTag[A] = ClassTag(xs.getClass.getComponentType) From 9909d95dd82fe4ee261862bca5d407c16fed9fab Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 15:45:58 +0100 Subject: [PATCH 43/89] Add LazyZipOps and some other files to stdlib --- .../stdlib/collection/BufferedIterator.scala | 32 ++ .../stdlib/collection/Hashing.scala | 63 +++ .../stdlib/collection/Iterable.scala | 2 +- .../stdlib/collection/JavaConverters.scala | 336 ++++++++++++++ .../stdlib/collection/LazyZipOps.scala | 423 ++++++++++++++++++ 5 files changed, 855 insertions(+), 1 deletion(-) create mode 100644 tests/pos-special/stdlib/collection/BufferedIterator.scala create mode 100644 tests/pos-special/stdlib/collection/Hashing.scala create mode 100644 tests/pos-special/stdlib/collection/JavaConverters.scala create mode 100644 tests/pos-special/stdlib/collection/LazyZipOps.scala diff --git a/tests/pos-special/stdlib/collection/BufferedIterator.scala b/tests/pos-special/stdlib/collection/BufferedIterator.scala new file mode 100644 index 000000000000..cca40dd31d40 --- /dev/null +++ b/tests/pos-special/stdlib/collection/BufferedIterator.scala @@ -0,0 +1,32 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +import language.experimental.captureChecking + +/** Buffered iterators are iterators which provide a method `head` + * that inspects the next element without discarding it. + */ +trait BufferedIterator[+A] extends Iterator[A] { + + /** Returns next element of iterator without advancing beyond it. + */ + def head: A + + /** Returns an option of the next element of an iterator without advancing beyond it. + * @return the next element of this iterator if it has a next element + * `None` if it does not + */ + def headOption : Option[A] = if (hasNext) Some(head) else None + + override def buffered: this.type = this +} diff --git a/tests/pos-special/stdlib/collection/Hashing.scala b/tests/pos-special/stdlib/collection/Hashing.scala new file mode 100644 index 000000000000..772dcf5c65da --- /dev/null +++ b/tests/pos-special/stdlib/collection/Hashing.scala @@ -0,0 +1,63 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +import language.experimental.captureChecking + + +protected[collection] object Hashing { + + def elemHashCode(key: Any): Int = key.## + + def improve(hcode: Int): Int = { + var h: Int = hcode + ~(hcode << 9) + h = h ^ (h >>> 14) + h = h + (h << 4) + h ^ (h >>> 10) + } + + def computeHash(key: Any): Int = + improve(elemHashCode(key)) + + /** + * Utility method to keep a subset of all bits in a given bitmap + * + * Example + * bitmap (binary): 00000001000000010000000100000001 + * keep (binary): 1010 + * result (binary): 00000001000000000000000100000000 + * + * @param bitmap the bitmap + * @param keep a bitmask containing which bits to keep + * @return the original bitmap with all bits where keep is not 1 set to 0 + */ + def keepBits(bitmap: Int, keep: Int): Int = { + var result = 0 + var current = bitmap + var kept = keep + while (kept != 0) { + // lowest remaining bit in current + val lsb = current ^ (current & (current - 1)) + if ((kept & 1) != 0) { + // mark bit in result bitmap + result |= lsb + } + // clear lowest remaining one bit in abm + current &= ~lsb + // look at the next kept bit + kept >>>= 1 + } + result + } + +} diff --git a/tests/pos-special/stdlib/collection/Iterable.scala b/tests/pos-special/stdlib/collection/Iterable.scala index 491d78a797dd..bca80d7be108 100644 --- a/tests/pos-special/stdlib/collection/Iterable.scala +++ b/tests/pos-special/stdlib/collection/Iterable.scala @@ -96,7 +96,7 @@ trait Iterable[+A] extends IterableOnce[A] * @return a decorator `LazyZip2` that allows strict operations to be performed on the lazily evaluated pairs * or chained calls to `lazyZip`. Implicit conversion to `Iterable[(A, B)]` is also supported. */ - def lazyZip[B](that: Iterable[B]): LazyZip2[A, B, this.type] = new LazyZip2(this, this, that) + def lazyZip[B](that: Iterable[B]^): LazyZip2[A, B, this.type]^{this, that} = new LazyZip2(this, this, that) } /** Base trait for Iterable operations diff --git a/tests/pos-special/stdlib/collection/JavaConverters.scala b/tests/pos-special/stdlib/collection/JavaConverters.scala new file mode 100644 index 000000000000..69130eae1829 --- /dev/null +++ b/tests/pos-special/stdlib/collection/JavaConverters.scala @@ -0,0 +1,336 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import java.util.{concurrent => juc} +import java.{lang => jl, util => ju} + +import scala.collection.convert._ +import scala.language.implicitConversions +import language.experimental.captureChecking + +/** A variety of decorators that enable converting between + * Scala and Java collections using extension methods, `asScala` and `asJava`. + * + * The extension methods return adapters for the corresponding API. + * + * The following conversions are supported via `asScala` and `asJava`: + *{{{ + * scala.collection.Iterable <=> java.lang.Iterable + * scala.collection.Iterator <=> java.util.Iterator + * scala.collection.mutable.Buffer <=> java.util.List + * scala.collection.mutable.Set <=> java.util.Set + * scala.collection.mutable.Map <=> java.util.Map + * scala.collection.concurrent.Map <=> java.util.concurrent.ConcurrentMap + *}}} + * The following conversions are supported via `asScala` and through + * specially-named extension methods to convert to Java collections, as shown: + *{{{ + * scala.collection.Iterable <=> java.util.Collection (via asJavaCollection) + * scala.collection.Iterator <=> java.util.Enumeration (via asJavaEnumeration) + * scala.collection.mutable.Map <=> java.util.Dictionary (via asJavaDictionary) + *}}} + * In addition, the following one-way conversions are provided via `asJava`: + *{{{ + * scala.collection.Seq => java.util.List + * scala.collection.mutable.Seq => java.util.List + * scala.collection.Set => java.util.Set + * scala.collection.Map => java.util.Map + *}}} + * The following one way conversion is provided via `asScala`: + *{{{ + * java.util.Properties => scala.collection.mutable.Map + *}}} + * In all cases, converting from a source type to a target type and back + * again will return the original source object. For example: + * {{{ + * import scala.collection.JavaConverters._ + * + * val source = new scala.collection.mutable.ListBuffer[Int] + * val target: java.util.List[Int] = source.asJava + * val other: scala.collection.mutable.Buffer[Int] = target.asScala + * assert(source eq other) + * }}} + * Alternatively, the conversion methods have descriptive names and can be invoked explicitly. + * {{{ + * scala> val vs = java.util.Arrays.asList("hi", "bye") + * vs: java.util.List[String] = [hi, bye] + * + * scala> val ss = asScalaIterator(vs.iterator) + * ss: Iterator[String] = + * + * scala> .toList + * res0: List[String] = List(hi, bye) + * + * scala> val ss = asScalaBuffer(vs) + * ss: scala.collection.mutable.Buffer[String] = Buffer(hi, bye) + * }}} + */ +@deprecated("Use `scala.jdk.CollectionConverters` instead", "2.13.0") +object JavaConverters extends AsJavaConverters with AsScalaConverters { + @deprecated("Use `asJava` instead", "2.13.0") + def asJavaIterator[A](i: Iterator[A]): ju.Iterator[A] = asJava(i) + + @deprecated("Use `asJava` instead", "2.13.0") + def asJavaIterable[A](i: Iterable[A]): jl.Iterable[A] = asJava(i) + + @deprecated("Use `asJava` instead", "2.13.0") + def bufferAsJavaList[A](b: mutable.Buffer[A]): ju.List[A] = asJava(b) + + @deprecated("Use `asJava` instead", "2.13.0") + def mutableSeqAsJavaList[A](s: mutable.Seq[A]): ju.List[A] = asJava(s) + + @deprecated("Use `asJava` instead", "2.13.0") + def seqAsJavaList[A](s: Seq[A]): ju.List[A] = asJava(s) + + @deprecated("Use `asJava` instead", "2.13.0") + def mutableSetAsJavaSet[A](s: mutable.Set[A]): ju.Set[A] = asJava(s) + + @deprecated("Use `asJava` instead", "2.13.0") + def setAsJavaSet[A](s: Set[A]): ju.Set[A] = asJava(s) + + @deprecated("Use `asJava` instead", "2.13.0") + def mutableMapAsJavaMap[K, V](m: mutable.Map[K, V]): ju.Map[K, V] = asJava(m) + + @deprecated("Use `asJava` instead", "2.13.0") + def mapAsJavaMap[K, V](m: Map[K, V]): ju.Map[K, V] = asJava(m) + + @deprecated("Use `asJava` instead", "2.13.0") + def mapAsJavaConcurrentMap[K, V](m: concurrent.Map[K, V]): juc.ConcurrentMap[K, V] = asJava(m) + + + @deprecated("Use `asScala` instead", "2.13.0") + def asScalaIterator[A](i: ju.Iterator[A]): Iterator[A] = asScala(i) + + @deprecated("Use `asScala` instead", "2.13.0") + def enumerationAsScalaIterator[A](i: ju.Enumeration[A]): Iterator[A] = asScala(i) + + @deprecated("Use `asScala` instead", "2.13.0") + def iterableAsScalaIterable[A](i: jl.Iterable[A]): Iterable[A] = asScala(i) + + @deprecated("Use `asScala` instead", "2.13.0") + def collectionAsScalaIterable[A](i: ju.Collection[A]): Iterable[A] = asScala(i) + + @deprecated("Use `asScala` instead", "2.13.0") + def asScalaBuffer[A](l: ju.List[A]): mutable.Buffer[A] = asScala(l) + + @deprecated("Use `asScala` instead", "2.13.0") + def asScalaSet[A](s: ju.Set[A]): mutable.Set[A] = asScala(s) + + @deprecated("Use `asScala` instead", "2.13.0") + def mapAsScalaMap[A, B](m: ju.Map[A, B]): mutable.Map[A, B] = asScala(m) + + @deprecated("Use `asScala` instead", "2.13.0") + def mapAsScalaConcurrentMap[A, B](m: juc.ConcurrentMap[A, B]): concurrent.Map[A, B] = asScala(m) + + @deprecated("Use `asScala` instead", "2.13.0") + def dictionaryAsScalaMap[A, B](p: ju.Dictionary[A, B]): mutable.Map[A, B] = asScala(p) + + @deprecated("Use `asScala` instead", "2.13.0") + def propertiesAsScalaMap(p: ju.Properties): mutable.Map[String, String] = asScala(p) + + // Deprecated implicit conversions for code that directly imports them + + /** + * Adds an `asJava` method that implicitly converts a Scala `Iterator` to a Java `Iterator`. + * @see [[asJavaIterator]] + */ + implicit def asJavaIteratorConverter[A](i : Iterator[A]): AsJava[ju.Iterator[A]] = + new AsJava(asJavaIterator(i)) + + /** + * Adds an `asJavaEnumeration` method that implicitly converts a Scala `Iterator` to a Java `Enumeration`. + * @see [[asJavaEnumeration]] + */ + implicit def asJavaEnumerationConverter[A](i : Iterator[A]): AsJavaEnumeration[A] = + new AsJavaEnumeration(i) + + /** + * Adds an `asJava` method that implicitly converts a Scala `Iterable` to a Java `Iterable`. + * @see [[asJavaIterable]] + */ + implicit def asJavaIterableConverter[A](i : Iterable[A]): AsJava[jl.Iterable[A]] = + new AsJava(asJavaIterable(i)) + + /** + * Adds an `asJavaCollection` method that implicitly converts a Scala `Iterable` to an immutable Java `Collection`. + * @see [[asJavaCollection]] + */ + implicit def asJavaCollectionConverter[A](i : Iterable[A]): AsJavaCollection[A] = + new AsJavaCollection(i) + + /** + * Adds an `asJava` method that implicitly converts a Scala mutable `Buffer` to a Java `List`. + * @see [[bufferAsJavaList]] + */ + implicit def bufferAsJavaListConverter[A](b : mutable.Buffer[A]): AsJava[ju.List[A]] = + new AsJava(bufferAsJavaList(b)) + + /** + * Adds an `asJava` method that implicitly converts a Scala mutable `Seq` to a Java `List`. + * @see [[mutableSeqAsJavaList]] + */ + implicit def mutableSeqAsJavaListConverter[A](b : mutable.Seq[A]): AsJava[ju.List[A]] = + new AsJava(mutableSeqAsJavaList(b)) + + /** + * Adds an `asJava` method that implicitly converts a Scala `Seq` to a Java `List`. + * @see [[seqAsJavaList]] + */ + implicit def seqAsJavaListConverter[A](b : Seq[A]): AsJava[ju.List[A]] = + new AsJava(seqAsJavaList(b)) + + /** + * Adds an `asJava` method that implicitly converts a Scala mutable `Set` to a Java `Set`. + * @see [[mutableSetAsJavaSet]] + */ + implicit def mutableSetAsJavaSetConverter[A](s : mutable.Set[A]): AsJava[ju.Set[A]] = + new AsJava(mutableSetAsJavaSet(s)) + + /** + * Adds an `asJava` method that implicitly converts a Scala `Set` to a Java `Set`. + * @see [[setAsJavaSet]] + */ + implicit def setAsJavaSetConverter[A](s : Set[A]): AsJava[ju.Set[A]] = + new AsJava(setAsJavaSet(s)) + + /** + * Adds an `asJava` method that implicitly converts a Scala mutable `Map` to a Java `Map`. + * @see [[mutableMapAsJavaMap]] + */ + implicit def mutableMapAsJavaMapConverter[K, V](m : mutable.Map[K, V]): AsJava[ju.Map[K, V]] = + new AsJava(mutableMapAsJavaMap(m)) + + /** + * Adds an `asJavaDictionary` method that implicitly converts a Scala mutable `Map` to a Java `Dictionary`. + * @see [[asJavaDictionary]] + */ + implicit def asJavaDictionaryConverter[K, V](m : mutable.Map[K, V]): AsJavaDictionary[K, V] = + new AsJavaDictionary(m) + + /** + * Adds an `asJava` method that implicitly converts a Scala `Map` to a Java `Map`. + * @see [[mapAsJavaMap]] + */ + implicit def mapAsJavaMapConverter[K, V](m : Map[K, V]): AsJava[ju.Map[K, V]] = + new AsJava(mapAsJavaMap(m)) + + /** + * Adds an `asJava` method that implicitly converts a Scala mutable `concurrent.Map` to a Java `ConcurrentMap`. + * @see [[mapAsJavaConcurrentMap]]. + */ + implicit def mapAsJavaConcurrentMapConverter[K, V](m: concurrent.Map[K, V]): AsJava[juc.ConcurrentMap[K, V]] = + new AsJava(mapAsJavaConcurrentMap(m)) + + + /** + * Adds an `asScala` method that implicitly converts a Java `Iterator` to a Scala `Iterator`. + * @see [[asScalaIterator]] + */ + implicit def asScalaIteratorConverter[A](i : ju.Iterator[A]): AsScala[Iterator[A]] = + new AsScala(asScalaIterator(i)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Enumeration` to a Scala `Iterator`. + * @see [[enumerationAsScalaIterator]] + */ + implicit def enumerationAsScalaIteratorConverter[A](i : ju.Enumeration[A]): AsScala[Iterator[A]] = + new AsScala(enumerationAsScalaIterator(i)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Iterable` to a Scala `Iterable`. + * @see [[iterableAsScalaIterable]] + */ + implicit def iterableAsScalaIterableConverter[A](i : jl.Iterable[A]): AsScala[Iterable[A]] = + new AsScala(iterableAsScalaIterable(i)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Collection` to an Scala `Iterable`. + * @see [[collectionAsScalaIterable]] + */ + implicit def collectionAsScalaIterableConverter[A](i : ju.Collection[A]): AsScala[Iterable[A]] = + new AsScala(collectionAsScalaIterable(i)) + + /** + * Adds an `asScala` method that implicitly converts a Java `List` to a Scala mutable `Buffer`. + * @see [[asScalaBuffer]] + */ + implicit def asScalaBufferConverter[A](l : ju.List[A]): AsScala[mutable.Buffer[A]] = + new AsScala(asScalaBuffer(l)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Set` to a Scala mutable `Set`. + * @see [[asScalaSet]] + */ + implicit def asScalaSetConverter[A](s : ju.Set[A]): AsScala[mutable.Set[A]] = + new AsScala(asScalaSet(s)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Map` to a Scala mutable `Map`. + * @see [[mapAsScalaMap]] + */ + implicit def mapAsScalaMapConverter[K, V](m : ju.Map[K, V]): AsScala[mutable.Map[K, V]] = + new AsScala(mapAsScalaMap(m)) + + /** + * Adds an `asScala` method that implicitly converts a Java `ConcurrentMap` to a Scala mutable `concurrent.Map`. + * @see [[mapAsScalaConcurrentMap]] + */ + implicit def mapAsScalaConcurrentMapConverter[K, V](m: juc.ConcurrentMap[K, V]): AsScala[concurrent.Map[K, V]] = + new AsScala(mapAsScalaConcurrentMap(m)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Dictionary` to a Scala mutable `Map`. + * @see [[dictionaryAsScalaMap]] + */ + implicit def dictionaryAsScalaMapConverter[K, V](p: ju.Dictionary[K, V]): AsScala[mutable.Map[K, V]] = + new AsScala(dictionaryAsScalaMap(p)) + + /** + * Adds an `asScala` method that implicitly converts a Java `Properties` to a Scala mutable `Map[String, String]`. + * @see [[propertiesAsScalaMap]] + */ + implicit def propertiesAsScalaMapConverter(p: ju.Properties): AsScala[mutable.Map[String, String]] = + new AsScala(propertiesAsScalaMap(p)) + + + /** Generic class containing the `asJava` converter method */ + class AsJava[A](op: => A) { + /** Converts a Scala collection to the corresponding Java collection */ + def asJava: A = op + } + + /** Generic class containing the `asScala` converter method */ + class AsScala[A](op: => A) { + /** Converts a Java collection to the corresponding Scala collection */ + def asScala: A = op + } + + /** Generic class containing the `asJavaCollection` converter method */ + class AsJavaCollection[A](i: Iterable[A]) { + /** Converts a Scala `Iterable` to a Java `Collection` */ + def asJavaCollection: ju.Collection[A] = JavaConverters.asJavaCollection(i) + } + + /** Generic class containing the `asJavaEnumeration` converter method */ + class AsJavaEnumeration[A](i: Iterator[A]) { + /** Converts a Scala `Iterator` to a Java `Enumeration` */ + def asJavaEnumeration: ju.Enumeration[A] = JavaConverters.asJavaEnumeration(i) + } + + /** Generic class containing the `asJavaDictionary` converter method */ + class AsJavaDictionary[K, V](m : mutable.Map[K, V]) { + /** Converts a Scala `Map` to a Java `Dictionary` */ + def asJavaDictionary: ju.Dictionary[K, V] = JavaConverters.asJavaDictionary(m) + } +} diff --git a/tests/pos-special/stdlib/collection/LazyZipOps.scala b/tests/pos-special/stdlib/collection/LazyZipOps.scala new file mode 100644 index 000000000000..1bb4173d219f --- /dev/null +++ b/tests/pos-special/stdlib/collection/LazyZipOps.scala @@ -0,0 +1,423 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import scala.language.implicitConversions +import language.experimental.captureChecking + +/** Decorator representing lazily zipped pairs. + * + * @define coll pair + * @define willNotTerminateInf + * + * Note: will not terminate for infinite-sized collections. + */ +final class LazyZip2[+El1, +El2, C1] private[collection](src: C1, coll1: Iterable[El1]^, coll2: Iterable[El2]^) { + + /** Zips `that` iterable collection with an existing `LazyZip2`. The elements in each collection are + * not consumed until a strict operation is invoked on the returned `LazyZip3` decorator. + * + * @param that the iterable providing the third element of each eventual triple + * @tparam B the type of the third element in each eventual triple + * @return a decorator `LazyZip3` that allows strict operations to be performed on the lazily evaluated tuples or + * chained calls to `lazyZip`. Implicit conversion to `Iterable[(El1, El2, B)]` is also supported. + */ + def lazyZip[B](that: Iterable[B]^): LazyZip3[El1, El2, B, C1]^{this, that} = new LazyZip3(src, coll1, coll2, that) + + def map[B, C](f: (El1, El2) => B)(implicit bf: BuildFrom[C1, B, C]): C = { + bf.fromSpecific(src)(new AbstractView[B] { + def iterator = new AbstractIterator[B] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + def hasNext = elems1.hasNext && elems2.hasNext + def next() = f(elems1.next(), elems2.next()) + } + override def knownSize: Int = zipKnownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty + }) + } + + def flatMap[B, C](f: (El1, El2) => Iterable[B])(implicit bf: BuildFrom[C1, B, C]): C = { + bf.fromSpecific(src)(new AbstractView[B] { + def iterator = new AbstractIterator[B] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] var _current: Iterator[B] = Iterator.empty + private def current = { + while (!_current.hasNext && elems1.hasNext && elems2.hasNext) + _current = f(elems1.next(), elems2.next()).iterator + _current + } + def hasNext = current.hasNext + def next() = current.next() + } + override def knownSize: Int = if (coll1.knownSize == 0 || coll2.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty + }) + } + + def filter[C](p: (El1, El2) => Boolean)(implicit bf: BuildFrom[C1, (El1, El2), C]): C = { + bf.fromSpecific(src)(new AbstractView[(El1, El2)] { + def iterator = new AbstractIterator[(El1, El2)] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] var _current: (El1, El2) = _ + private def current = { + while ((_current eq null) && elems1.hasNext && elems2.hasNext) { + val e1 = elems1.next() + val e2 = elems2.next() + if (p(e1, e2)) _current = (e1, e2) + } + _current + } + def hasNext = current ne null + def next() = { + val c = current + if (c ne null) { + _current = null + c + } else Iterator.empty.next() + } + } + override def knownSize: Int = if (coll1.knownSize == 0 || coll2.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.hasNext + }) + } + + def exists(p: (El1, El2) => Boolean): Boolean = { + val elems1 = coll1.iterator + val elems2 = coll2.iterator + var res = false + + while (!res && elems1.hasNext && elems2.hasNext) res = p(elems1.next(), elems2.next()) + + res + } + + def forall(p: (El1, El2) => Boolean): Boolean = !exists((el1, el2) => !p(el1, el2)) + + def foreach[U](f: (El1, El2) => U): Unit = { + val elems1 = coll1.iterator + val elems2 = coll2.iterator + + while (elems1.hasNext && elems2.hasNext) f(elems1.next(), elems2.next()) + } + + private def toIterable: View[(El1, El2)] = new AbstractView[(El1, El2)] { + def iterator = new AbstractIterator[(El1, El2)] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + def hasNext = elems1.hasNext && elems2.hasNext + def next() = (elems1.next(), elems2.next()) + } + override def knownSize: Int = zipKnownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty + } + + private def zipKnownSize: Int = { + val s1 = coll1.knownSize + if (s1 == 0) 0 else { + val s2 = coll2.knownSize + if (s2 == 0) 0 else s1 min s2 + } + } + + override def toString = s"$coll1.lazyZip($coll2)" +} + +object LazyZip2 { + implicit def lazyZip2ToIterable[El1, El2](zipped2: LazyZip2[El1, El2, _]): View[(El1, El2)] = zipped2.toIterable +} + + +/** Decorator representing lazily zipped triples. + * + * @define coll triple + * @define willNotTerminateInf + * + * Note: will not terminate for infinite-sized collections. + */ +final class LazyZip3[+El1, +El2, +El3, C1] private[collection](src: C1, + coll1: Iterable[El1]^, + coll2: Iterable[El2]^, + coll3: Iterable[El3]^) { + + /** Zips `that` iterable collection with an existing `LazyZip3`. The elements in each collection are + * not consumed until a strict operation is invoked on the returned `LazyZip4` decorator. + * + * @param that the iterable providing the fourth element of each eventual 4-tuple + * @tparam B the type of the fourth element in each eventual 4-tuple + * @return a decorator `LazyZip4` that allows strict operations to be performed on the lazily evaluated tuples. + * Implicit conversion to `Iterable[(El1, El2, El3, B)]` is also supported. + */ + def lazyZip[B](that: Iterable[B]^): LazyZip4[El1, El2, El3, B, C1]^{this, that} = new LazyZip4(src, coll1, coll2, coll3, that) + + def map[B, C](f: (El1, El2, El3) => B)(implicit bf: BuildFrom[C1, B, C]): C = { + bf.fromSpecific(src)(new AbstractView[B] { + def iterator = new AbstractIterator[B] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + def hasNext = elems1.hasNext && elems2.hasNext && elems3.hasNext + def next() = f(elems1.next(), elems2.next(), elems3.next()) + } + override def knownSize: Int = zipKnownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty || coll3.isEmpty + }) + } + + def flatMap[B, C](f: (El1, El2, El3) => Iterable[B])(implicit bf: BuildFrom[C1, B, C]): C = { + bf.fromSpecific(src)(new AbstractView[B] { + def iterator = new AbstractIterator[B] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + private[this] var _current: Iterator[B] = Iterator.empty + private def current = { + while (!_current.hasNext && elems1.hasNext && elems2.hasNext && elems3.hasNext) + _current = f(elems1.next(), elems2.next(), elems3.next()).iterator + _current + } + def hasNext = current.hasNext + def next() = current.next() + } + override def knownSize: Int = if (coll1.knownSize == 0 || coll2.knownSize == 0 || coll3.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.isEmpty + }) + } + + def filter[C](p: (El1, El2, El3) => Boolean)(implicit bf: BuildFrom[C1, (El1, El2, El3), C]): C = { + bf.fromSpecific(src)(new AbstractView[(El1, El2, El3)] { + def iterator = new AbstractIterator[(El1, El2, El3)] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + private[this] var _current: (El1, El2, El3) = _ + private def current = { + while ((_current eq null) && elems1.hasNext && elems2.hasNext && elems3.hasNext) { + val e1 = elems1.next() + val e2 = elems2.next() + val e3 = elems3.next() + if (p(e1, e2, e3)) _current = (e1, e2, e3) + } + _current + } + def hasNext = current ne null + def next() = { + val c = current + if (c ne null) { + _current = null + c + } else Iterator.empty.next() + } + } + override def knownSize: Int = if (coll1.knownSize == 0 || coll2.knownSize == 0 || coll3.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.isEmpty + }) + } + + def exists(p: (El1, El2, El3) => Boolean): Boolean = { + val elems1 = coll1.iterator + val elems2 = coll2.iterator + val elems3 = coll3.iterator + var res = false + + while (!res && elems1.hasNext && elems2.hasNext && elems3.hasNext) + res = p(elems1.next(), elems2.next(), elems3.next()) + + res + } + + def forall(p: (El1, El2, El3) => Boolean): Boolean = !exists((el1, el2, el3) => !p(el1, el2, el3)) + + def foreach[U](f: (El1, El2, El3) => U): Unit = { + val elems1 = coll1.iterator + val elems2 = coll2.iterator + val elems3 = coll3.iterator + + while (elems1.hasNext && elems2.hasNext && elems3.hasNext) + f(elems1.next(), elems2.next(), elems3.next()) + } + + private def toIterable: View[(El1, El2, El3)] = new AbstractView[(El1, El2, El3)] { + def iterator = new AbstractIterator[(El1, El2, El3)] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + def hasNext = elems1.hasNext && elems2.hasNext && elems3.hasNext + def next() = (elems1.next(), elems2.next(), elems3.next()) + } + override def knownSize: Int = zipKnownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty || coll3.isEmpty + } + + private def zipKnownSize: Int = { + val s1 = coll1.knownSize + if (s1 == 0) 0 else { + val s2 = coll2.knownSize + if (s2 == 0) 0 else { + val s3 = coll3.knownSize + if (s3 == 0) 0 else s1 min s2 min s3 + } + } + } + + override def toString = s"$coll1.lazyZip($coll2).lazyZip($coll3)" +} + +object LazyZip3 { + implicit def lazyZip3ToIterable[El1, El2, El3](zipped3: LazyZip3[El1, El2, El3, _]): View[(El1, El2, El3)] = zipped3.toIterable +} + + + +/** Decorator representing lazily zipped 4-tuples. + * + * @define coll tuple + * @define willNotTerminateInf + * + * Note: will not terminate for infinite-sized collections. + */ +final class LazyZip4[+El1, +El2, +El3, +El4, C1] private[collection](src: C1, + coll1: Iterable[El1]^, + coll2: Iterable[El2]^, + coll3: Iterable[El3]^, + coll4: Iterable[El4]^) { + + def map[B, C](f: (El1, El2, El3, El4) => B)(implicit bf: BuildFrom[C1, B, C]): C = { + bf.fromSpecific(src)(new AbstractView[B] { + def iterator = new AbstractIterator[B] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + private[this] val elems4 = coll4.iterator + def hasNext = elems1.hasNext && elems2.hasNext && elems3.hasNext && elems4.hasNext + def next() = f(elems1.next(), elems2.next(), elems3.next(), elems4.next()) + } + override def knownSize: Int = zipKnownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty || coll3.isEmpty || coll4.isEmpty + }) + } + + def flatMap[B, C](f: (El1, El2, El3, El4) => Iterable[B])(implicit bf: BuildFrom[C1, B, C]): C = { + bf.fromSpecific(src)(new AbstractView[B] { + def iterator = new AbstractIterator[B] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + private[this] val elems4 = coll4.iterator + private[this] var _current: Iterator[B] = Iterator.empty + private def current = { + while (!_current.hasNext && elems1.hasNext && elems2.hasNext && elems3.hasNext && elems4.hasNext) + _current = f(elems1.next(), elems2.next(), elems3.next(), elems4.next()).iterator + _current + } + def hasNext = current.hasNext + def next() = current.next() + } + override def knownSize: Int = if (coll1.knownSize == 0 || coll2.knownSize == 0 || coll3.knownSize == 0 || coll4.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.isEmpty + }) + } + + def filter[C](p: (El1, El2, El3, El4) => Boolean)(implicit bf: BuildFrom[C1, (El1, El2, El3, El4), C]): C = { + bf.fromSpecific(src)(new AbstractView[(El1, El2, El3, El4)] { + def iterator = new AbstractIterator[(El1, El2, El3, El4)] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + private[this] val elems4 = coll4.iterator + private[this] var _current: (El1, El2, El3, El4) = _ + private def current = { + while ((_current eq null) && elems1.hasNext && elems2.hasNext && elems3.hasNext && elems4.hasNext) { + val e1 = elems1.next() + val e2 = elems2.next() + val e3 = elems3.next() + val e4 = elems4.next() + if (p(e1, e2, e3, e4)) _current = (e1, e2, e3, e4) + } + _current + } + def hasNext = current ne null + def next() = { + val c = current + if (c ne null) { + _current = null + c + } else Iterator.empty.next() + } + } + override def knownSize: Int = if (coll1.knownSize == 0 || coll2.knownSize == 0 || coll3.knownSize == 0 || coll4.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.isEmpty + }) + } + + def exists(p: (El1, El2, El3, El4) => Boolean): Boolean = { + val elems1 = coll1.iterator + val elems2 = coll2.iterator + val elems3 = coll3.iterator + val elems4 = coll4.iterator + var res = false + + while (!res && elems1.hasNext && elems2.hasNext && elems3.hasNext && elems4.hasNext) + res = p(elems1.next(), elems2.next(), elems3.next(), elems4.next()) + + res + } + + def forall(p: (El1, El2, El3, El4) => Boolean): Boolean = !exists((el1, el2, el3, el4) => !p(el1, el2, el3, el4)) + + def foreach[U](f: (El1, El2, El3, El4) => U): Unit = { + val elems1 = coll1.iterator + val elems2 = coll2.iterator + val elems3 = coll3.iterator + val elems4 = coll4.iterator + + while (elems1.hasNext && elems2.hasNext && elems3.hasNext && elems4.hasNext) + f(elems1.next(), elems2.next(), elems3.next(), elems4.next()) + } + + private def toIterable: View[(El1, El2, El3, El4)] = new AbstractView[(El1, El2, El3, El4)] { + def iterator = new AbstractIterator[(El1, El2, El3, El4)] { + private[this] val elems1 = coll1.iterator + private[this] val elems2 = coll2.iterator + private[this] val elems3 = coll3.iterator + private[this] val elems4 = coll4.iterator + def hasNext = elems1.hasNext && elems2.hasNext && elems3.hasNext && elems4.hasNext + def next() = (elems1.next(), elems2.next(), elems3.next(), elems4.next()) + } + override def knownSize: Int = zipKnownSize + override def isEmpty: Boolean = coll1.isEmpty || coll2.isEmpty || coll3.isEmpty || coll4.isEmpty + } + + private def zipKnownSize: Int = { + val s1 = coll1.knownSize + if (s1 == 0) 0 else { + val s2 = coll2.knownSize + if (s2 == 0) 0 else { + val s3 = coll3.knownSize + if (s3 == 0) 0 else { + val s4 = coll4.knownSize + if (s4 == 0) 0 else s1 min s2 min s3 min s4 + } + } + } + } + + override def toString = s"$coll1.lazyZip($coll2).lazyZip($coll3).lazyZip($coll4)" +} + +object LazyZip4 { + implicit def lazyZip4ToIterable[El1, El2, El3, El4](zipped4: LazyZip4[El1, El2, El3, El4, _]): View[(El1, El2, El3, El4)] = + zipped4.toIterable +} From caeac209d0d0f92ebdd3f32961e058a20cb458bb Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 15:53:08 +0100 Subject: [PATCH 44/89] Add mutable/TreeSet.scala to stdlib --- tests/pos-special/stdlib/collection/Set.scala | 3 +- .../collection/StrictOptimizedSetOps.scala | 30 +++ .../stdlib/collection/mutable/TreeSet.scala | 219 ++++++++++++++++++ 3 files changed, 251 insertions(+), 1 deletion(-) create mode 100644 tests/pos-special/stdlib/collection/StrictOptimizedSetOps.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/TreeSet.scala diff --git a/tests/pos-special/stdlib/collection/Set.scala b/tests/pos-special/stdlib/collection/Set.scala index 75707f204c02..a9c279b82a49 100644 --- a/tests/pos-special/stdlib/collection/Set.scala +++ b/tests/pos-special/stdlib/collection/Set.scala @@ -25,7 +25,8 @@ trait Set[A] extends Iterable[A] with SetOps[A, Set, Set[A]] with Equals - with IterableFactoryDefaults[A, Set] { + with IterableFactoryDefaults[A, Set] + with Pure { self: Set[A] => def canEqual(that: Any) = true diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedSetOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedSetOps.scala new file mode 100644 index 000000000000..8ed337fff998 --- /dev/null +++ b/tests/pos-special/stdlib/collection/StrictOptimizedSetOps.scala @@ -0,0 +1,30 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +import language.experimental.captureChecking + +/** + * Trait that overrides set operations to take advantage of strict builders. + * + * @tparam A Elements type + * @tparam CC Collection type constructor + * @tparam C Collection type + */ +trait StrictOptimizedSetOps[A, +CC[_], +C <: SetOps[A, CC, C]] + extends SetOps[A, CC, C] + with StrictOptimizedIterableOps[A, CC, C] { + + override def concat(that: IterableOnce[A]): C = + strictOptimizedConcat(that, newSpecificBuilder) + +} diff --git a/tests/pos-special/stdlib/collection/mutable/TreeSet.scala b/tests/pos-special/stdlib/collection/mutable/TreeSet.scala new file mode 100644 index 000000000000..59c68a768351 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/TreeSet.scala @@ -0,0 +1,219 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.mutable + +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.mutable.{RedBlackTree => RB} +import scala.collection.{SortedIterableFactory, SortedSetFactoryDefaults, Stepper, StepperShape, StrictOptimizedIterableOps, StrictOptimizedSortedSetOps, mutable} +import language.experimental.captureChecking + +/** + * A mutable sorted set implemented using a mutable red-black tree as underlying data structure. + * + * @param ordering the implicit ordering used to compare objects of type `A`. + * @tparam A the type of the keys contained in this tree set. + * + * @define Coll mutable.TreeSet + * @define coll mutable tree set + */ +// Original API designed in part by Lucien Pereira +sealed class TreeSet[A] private (private val tree: RB.Tree[A, Null])(implicit val ordering: Ordering[A]) + extends AbstractSet[A] + with SortedSet[A] + with SortedSetOps[A, TreeSet, TreeSet[A]] + with StrictOptimizedIterableOps[A, Set, TreeSet[A]] + with StrictOptimizedSortedSetOps[A, TreeSet, TreeSet[A]] + with SortedSetFactoryDefaults[A, TreeSet, Set] + with DefaultSerializable { + + if (ordering eq null) + throw new NullPointerException("ordering must not be null") + + /** + * Creates an empty `TreeSet`. + * @param ord the implicit ordering used to compare objects of type `A`. + * @return an empty `TreeSet`. + */ + def this()(implicit ord: Ordering[A]) = this(RB.Tree.empty)(ord) + + override def sortedIterableFactory: SortedIterableFactory[TreeSet] = TreeSet + + def iterator: collection.Iterator[A] = RB.keysIterator(tree) + + def iteratorFrom(start: A): collection.Iterator[A] = RB.keysIterator(tree, Some(start)) + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + type T = RB.Node[A, Null] + val s = shape.shape match { + case StepperShape.IntShape => IntBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.key.asInstanceOf[Int]) + case StepperShape.LongShape => LongBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.key.asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleBinaryTreeStepper.from[T](size, tree.root, _.left, _.right, _.key.asInstanceOf[Double]) + case _ => shape.parUnbox(AnyBinaryTreeStepper.from[A, T](size, tree.root, _.left, _.right, _.key)) + } + s.asInstanceOf[S with EfficientSplit] + } + + def addOne(elem: A): this.type = { + RB.insert(tree, elem, null) + this + } + + def subtractOne(elem: A): this.type = { + RB.delete(tree, elem) + this + } + + def clear(): Unit = RB.clear(tree) + + def contains(elem: A): Boolean = RB.contains(tree, elem) + + def unconstrained: collection.Set[A] = this + + def rangeImpl(from: Option[A], until: Option[A]): TreeSet[A] = new TreeSetProjection(from, until) + + override protected[this] def className: String = "TreeSet" + + override def size: Int = RB.size(tree) + override def knownSize: Int = size + override def isEmpty: Boolean = RB.isEmpty(tree) + + override def head: A = RB.minKey(tree).get + + override def last: A = RB.maxKey(tree).get + + override def minAfter(key: A): Option[A] = RB.minKeyAfter(tree, key) + + override def maxBefore(key: A): Option[A] = RB.maxKeyBefore(tree, key) + + override def foreach[U](f: A => U): Unit = RB.foreachKey(tree, f) + + + /** + * A ranged projection of a [[TreeSet]]. Mutations on this set affect the original set and vice versa. + * + * Only keys between this projection's key range will ever appear as elements of this set, independently of whether + * the elements are added through the original set or through this view. That means that if one inserts an element in + * a view whose key is outside the view's bounds, calls to `contains` will _not_ consider the newly added element. + * Mutations are always reflected in the original set, though. + * + * @param from the lower bound (inclusive) of this projection wrapped in a `Some`, or `None` if there is no lower + * bound. + * @param until the upper bound (exclusive) of this projection wrapped in a `Some`, or `None` if there is no upper + * bound. + */ + private[this] final class TreeSetProjection(from: Option[A], until: Option[A]) extends TreeSet[A](tree) { + + /** + * Given a possible new lower bound, chooses and returns the most constraining one (the maximum). + */ + private[this] def pickLowerBound(newFrom: Option[A]): Option[A] = (from, newFrom) match { + case (Some(fr), Some(newFr)) => Some(ordering.max(fr, newFr)) + case (None, _) => newFrom + case _ => from + } + + /** + * Given a possible new upper bound, chooses and returns the most constraining one (the minimum). + */ + private[this] def pickUpperBound(newUntil: Option[A]): Option[A] = (until, newUntil) match { + case (Some(unt), Some(newUnt)) => Some(ordering.min(unt, newUnt)) + case (None, _) => newUntil + case _ => until + } + + /** + * Returns true if the argument is inside the view bounds (between `from` and `until`). + */ + private[this] def isInsideViewBounds(key: A): Boolean = { + val afterFrom = from.isEmpty || ordering.compare(from.get, key) <= 0 + val beforeUntil = until.isEmpty || ordering.compare(key, until.get) < 0 + afterFrom && beforeUntil + } + + override def rangeImpl(from: Option[A], until: Option[A]): TreeSet[A] = + new TreeSetProjection(pickLowerBound(from), pickUpperBound(until)) + + override def contains(key: A) = isInsideViewBounds(key) && RB.contains(tree, key) + + override def iterator = RB.keysIterator(tree, from, until) + override def iteratorFrom(start: A) = RB.keysIterator(tree, pickLowerBound(Some(start)), until) + + override def size = if (RB.size(tree) == 0) 0 else iterator.length + override def knownSize: Int = if (RB.size(tree) == 0) 0 else -1 + override def isEmpty: Boolean = RB.size(tree) == 0 || !iterator.hasNext + + override def head: A = headOption.get + override def headOption: Option[A] = { + val elem = if (from.isDefined) RB.minKeyAfter(tree, from.get) else RB.minKey(tree) + (elem, until) match { + case (Some(e), Some(unt)) if ordering.compare(e, unt) >= 0 => None + case _ => elem + } + } + + override def last: A = lastOption.get + override def lastOption = { + val elem = if (until.isDefined) RB.maxKeyBefore(tree, until.get) else RB.maxKey(tree) + (elem, from) match { + case (Some(e), Some(fr)) if ordering.compare(e, fr) < 0 => None + case _ => elem + } + } + + // Using the iterator should be efficient enough; if performance is deemed a problem later, a specialized + // `foreachKey(f, from, until)` method can be created in `RedBlackTree`. See + // https://github.com/scala/scala/pull/4608#discussion_r34307985 for a discussion about this. + override def foreach[U](f: A => U): Unit = iterator.foreach(f) + + override def clone(): mutable.TreeSet[A] = super.clone().rangeImpl(from, until) + + } + +} + +/** + * $factoryInfo + * @define Coll `mutable.TreeSet` + * @define coll mutable tree set + */ +@SerialVersionUID(3L) +object TreeSet extends SortedIterableFactory[TreeSet] { + + def empty[A : Ordering]: TreeSet[A] = new TreeSet[A]() + + def from[E](it: IterableOnce[E]^)(implicit ordering: Ordering[E]): TreeSet[E] = + it match { + case ts: TreeSet[E] if ordering == ts.ordering => + new TreeSet[E](ts.tree.treeCopy()) + case ss: scala.collection.SortedSet[E] if ordering == ss.ordering => + new TreeSet[E](RB.fromOrderedKeys(ss.iterator, ss.size)) + case r: Range if (ordering eq Ordering.Int) || (ordering eq Ordering.Int.reverse) => + val it = if((ordering eq Ordering.Int) == (r.step > 0)) r.iterator else r.reverseIterator + new TreeSet[E](RB.fromOrderedKeys(it.asInstanceOf[Iterator[E]], r.size)) + case _ => + val t: RB.Tree[E, Null] = RB.Tree.empty + val i = it.iterator + while (i.hasNext) RB.insert(t, i.next(), null) + new TreeSet[E](t) + } + + def newBuilder[A](implicit ordering: Ordering[A]): Builder[A, TreeSet[A]] = new ReusableBuilder[A, TreeSet[A]] { + private[this] var tree: RB.Tree[A, Null] = RB.Tree.empty + def addOne(elem: A): this.type = { RB.insert(tree, elem, null); this } + def result(): TreeSet[A] = new TreeSet[A](tree) + def clear(): Unit = { tree = RB.Tree.empty } + } +} From 1f4f8755f7c3e3309114173c45e9204b5cfe01bb Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 16:01:31 +0100 Subject: [PATCH 45/89] Add mutable and concurrent Map to stdlib --- tests/pos-special/stdlib/collection/Map.scala | 3 +- .../stdlib/collection/concurrent/Map.scala | 193 +++++++++++++ .../stdlib/collection/mutable/Map.scala | 271 ++++++++++++++++++ 3 files changed, 466 insertions(+), 1 deletion(-) create mode 100644 tests/pos-special/stdlib/collection/concurrent/Map.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/Map.scala diff --git a/tests/pos-special/stdlib/collection/Map.scala b/tests/pos-special/stdlib/collection/Map.scala index bcfd8d593eda..6816a1fd174a 100644 --- a/tests/pos-special/stdlib/collection/Map.scala +++ b/tests/pos-special/stdlib/collection/Map.scala @@ -24,7 +24,8 @@ trait Map[K, +V] extends Iterable[(K, V)] with MapOps[K, V, Map, Map[K, V]] with MapFactoryDefaults[K, V, Map, Iterable] - with Equals { + with Equals + with Pure { def mapFactory: scala.collection.MapFactory[Map] = Map diff --git a/tests/pos-special/stdlib/collection/concurrent/Map.scala b/tests/pos-special/stdlib/collection/concurrent/Map.scala new file mode 100644 index 000000000000..d985dad2edc5 --- /dev/null +++ b/tests/pos-special/stdlib/collection/concurrent/Map.scala @@ -0,0 +1,193 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.concurrent + +import language.experimental.captureChecking +import scala.annotation.tailrec + +/** A template trait for mutable maps that allow concurrent access. + * + * $concurrentmapinfo + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#concurrent_maps "Scala's Collection Library overview"]] + * section on `Concurrent Maps` for more information. + * + * @tparam K the key type of the map + * @tparam V the value type of the map + * + * @define Coll `concurrent.Map` + * @define coll concurrent map + * @define concurrentmapinfo + * This is a base trait for all Scala concurrent map implementations. It + * provides all of the methods a `Map` does, with the difference that all the + * changes are atomic. It also describes methods specific to concurrent maps. + * + * '''Note''': The concurrent maps do not accept `'''null'''` for keys or values. + * + * @define atomicop + * This is an atomic operation. + */ +trait Map[K, V] extends scala.collection.mutable.Map[K, V] { + + /** + * Associates the given key with a given value, unless the key was already + * associated with some other value. + * + * $atomicop + * + * @param k key with which the specified value is to be associated with + * @param v value to be associated with the specified key + * @return `Some(oldvalue)` if there was a value `oldvalue` previously + * associated with the specified key, or `None` if there was no + * mapping for the specified key + */ + def putIfAbsent(k: K, v: V): Option[V] + + /** + * Removes the entry for the specified key if it's currently mapped to the + * specified value. + * + * $atomicop + * + * @param k key for which the entry should be removed + * @param v value expected to be associated with the specified key if + * the removal is to take place + * @return `true` if the removal took place, `false` otherwise + */ + def remove(k: K, v: V): Boolean + + /** + * Replaces the entry for the given key only if it was previously mapped to + * a given value. + * + * $atomicop + * + * @param k key for which the entry should be replaced + * @param oldvalue value expected to be associated with the specified key + * if replacing is to happen + * @param newvalue value to be associated with the specified key + * @return `true` if the entry was replaced, `false` otherwise + */ + def replace(k: K, oldvalue: V, newvalue: V): Boolean + + /** + * Replaces the entry for the given key only if it was previously mapped + * to some value. + * + * $atomicop + * + * @param k key for which the entry should be replaced + * @param v value to be associated with the specified key + * @return `Some(v)` if the given key was previously mapped to some value `v`, or `None` otherwise + */ + def replace(k: K, v: V): Option[V] + + override def getOrElseUpdate(key: K, op: => V): V = get(key) match { + case Some(v) => v + case None => + val v = op + putIfAbsent(key, v) match { + case Some(ov) => ov + case None => v + } + } + + /** + * Removes the entry for the specified key if it's currently mapped to the + * specified value. Comparison to the specified value is done using reference + * equality. + * + * Not all map implementations can support removal based on reference + * equality, and for those implementations, object equality is used instead. + * + * $atomicop + * + * @param k key for which the entry should be removed + * @param v value expected to be associated with the specified key if + * the removal is to take place + * @return `true` if the removal took place, `false` otherwise + */ + // TODO: make part of the API in a future version + private[collection] def removeRefEq(k: K, v: V): Boolean = remove(k, v) + + /** + * Replaces the entry for the given key only if it was previously mapped to + * a given value. Comparison to the specified value is done using reference + * equality. + * + * Not all map implementations can support replacement based on reference + * equality, and for those implementations, object equality is used instead. + * + * $atomicop + * + * @param k key for which the entry should be replaced + * @param oldValue value expected to be associated with the specified key + * if replacing is to happen + * @param newValue value to be associated with the specified key + * @return `true` if the entry was replaced, `false` otherwise + */ + // TODO: make part of the API in a future version + private[collection] def replaceRefEq(k: K, oldValue: V, newValue: V): Boolean = replace(k, oldValue, newValue) + + /** + * Update a mapping for the specified key and its current optionally-mapped value + * (`Some` if there is current mapping, `None` if not). + * + * If the remapping function returns `Some(v)`, the mapping is updated with the new value `v`. + * If the remapping function returns `None`, the mapping is removed (or remains absent if initially absent). + * If the function itself throws an exception, the exception is rethrown, and the current mapping is left unchanged. + * + * If the map is updated by another concurrent access, the remapping function will be retried until successfully updated. + * + * @param key the key value + * @param remappingFunction a partial function that receives current optionally-mapped value and return a new mapping + * @return the new value associated with the specified key + */ + override def updateWith(key: K)(remappingFunction: Option[V] => Option[V]): Option[V] = updateWithAux(key)(remappingFunction) + + @tailrec + private def updateWithAux(key: K)(remappingFunction: Option[V] => Option[V]): Option[V] = { + val previousValue = get(key) + val nextValue = remappingFunction(previousValue) + previousValue match { + case Some(prev) => nextValue match { + case Some(next) => if (replaceRefEq(key, prev, next)) return nextValue + case _ => if (removeRefEq(key, prev)) return None + } + case _ => nextValue match { + case Some(next) => if (putIfAbsent(key, next).isEmpty) return nextValue + case _ => return None + } + } + updateWithAux(key)(remappingFunction) + } + + private[collection] def filterInPlaceImpl(p: (K, V) => Boolean): this.type = { + val it = iterator + while (it.hasNext) { + val (k, v) = it.next() + if (!p(k, v)) removeRefEq(k, v) + } + this + } + + private[collection] def mapValuesInPlaceImpl(f: (K, V) => V): this.type = { + val it = iterator + while (it.hasNext) { + val (k, v) = it.next() + replaceRefEq(k, v, f(k, v)) + } + this + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/Map.scala b/tests/pos-special/stdlib/collection/mutable/Map.scala new file mode 100644 index 000000000000..dab64ddb1f58 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/Map.scala @@ -0,0 +1,271 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import language.experimental.captureChecking + +/** Base type of mutable Maps */ +trait Map[K, V] + extends Iterable[(K, V)] + with collection.Map[K, V] + with MapOps[K, V, Map, Map[K, V]] + with Growable[(K, V)] + with Shrinkable[K] + with MapFactoryDefaults[K, V, Map, Iterable] { + + override def mapFactory: scala.collection.MapFactory[Map] = Map + + /* + //TODO consider keeping `remove` because it returns the removed entry + @deprecated("Use subtract or -= instead of remove", "2.13.0") + def remove(key: K): Option[V] = { + val old = get(key) + if(old.isDefined) subtract(key) + old + } + */ + + /** The same map with a given default function. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefaultValue`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d the function mapping keys to values, used for non-present keys + * @return a wrapper of the map with a default value + */ + def withDefault(d: K -> V): Map[K, V] = new Map.WithDefault[K, V](this, d) + + /** The same map with a given default value. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefaultValue`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d default value used for non-present keys + * @return a wrapper of the map with a default value + */ + def withDefaultValue(d: V): Map[K, V] = new Map.WithDefault[K, V](this, x => d) +} + +/** + * @define coll mutable map + * @define Coll `mutable.Map` + */ +trait MapOps[K, V, +CC[X, Y] <: MapOps[X, Y, CC, _], +C <: MapOps[K, V, CC, C]] + extends IterableOps[(K, V), Iterable, C] + with collection.MapOps[K, V, CC, C] + with Cloneable[C] + with Builder[(K, V), C] + with Growable[(K, V)] + with Shrinkable[K] + with Pure { + + def result(): C = coll + + @deprecated("Use - or remove on an immutable Map", "2.13.0") + final def - (key: K): C = clone() -= key + + @deprecated("Use -- or removeAll on an immutable Map", "2.13.0") + final def - (key1: K, key2: K, keys: K*): C = clone() -= key1 -= key2 --= keys + + /** Adds a new key/value pair to this map and optionally returns previously bound value. + * If the map already contains a + * mapping for the key, it will be overridden by the new value. + * + * @param key the key to update + * @param value the new value + * @return an option value containing the value associated with the key + * before the `put` operation was executed, or `None` if `key` + * was not defined in the map before. + */ + def put(key: K, value: V): Option[V] = { + val r = get(key) + update(key, value) + r + } + + /** Adds a new key/value pair to this map. + * If the map already contains a + * mapping for the key, it will be overridden by the new value. + * + * @param key The key to update + * @param value The new value + */ + def update(key: K, value: V): Unit = { coll += ((key, value)) } + + /** + * Update a mapping for the specified key and its current optionally-mapped value + * (`Some` if there is current mapping, `None` if not). + * + * If the remapping function returns `Some(v)`, the mapping is updated with the new value `v`. + * If the remapping function returns `None`, the mapping is removed (or remains absent if initially absent). + * If the function itself throws an exception, the exception is rethrown, and the current mapping is left unchanged. + * + * @param key the key value + * @param remappingFunction a partial function that receives current optionally-mapped value and return a new mapping + * @return the new value associated with the specified key + */ + def updateWith(key: K)(remappingFunction: Option[V] => Option[V]): Option[V] = { + val previousValue = this.get(key) + val nextValue = remappingFunction(previousValue) + (previousValue, nextValue) match { + case (None, None) => // do nothing + case (Some(_), None) => this.remove(key) + case (_, Some(v)) => this.update(key,v) + } + nextValue + } + + /** If given key is already in this map, returns associated value. + * + * Otherwise, computes value from given expression `op`, stores with key + * in map and returns that value. + * + * Concurrent map implementations may evaluate the expression `op` + * multiple times, or may evaluate `op` without inserting the result. + * + * @param key the key to test + * @param op the computation yielding the value to associate with `key`, if + * `key` is previously unbound. + * @return the value associated with key (either previously or as a result + * of executing the method). + */ + def getOrElseUpdate(key: K, op: => V): V = + get(key) match { + case Some(v) => v + case None => val d = op; this(key) = d; d + } + + /** Removes a key from this map, returning the value associated previously + * with that key as an option. + * @param key the key to be removed + * @return an option value containing the value associated previously with `key`, + * or `None` if `key` was not defined in the map before. + */ + def remove(key: K): Option[V] = { + val r = get(key) + if (r.isDefined) this -= key + r + } + + def clear(): Unit = { keysIterator foreach -= } + + override def clone(): C = empty ++= this + + @deprecated("Use filterInPlace instead", "2.13.0") + @inline final def retain(p: (K, V) => Boolean): this.type = filterInPlace(p) + + /** Retains only those mappings for which the predicate + * `p` returns `true`. + * + * @param p The test predicate + */ + def filterInPlace(p: (K, V) => Boolean): this.type = { + if (!isEmpty) this match { + case tm: concurrent.Map[_, _] => tm.asInstanceOf[concurrent.Map[K, V]].filterInPlaceImpl(p) + case _ => + val array = this.toArray[Any] // scala/bug#7269 toArray avoids ConcurrentModificationException + val arrayLength = array.length + var i = 0 + while (i < arrayLength) { + val (k, v) = array(i).asInstanceOf[(K, V)] + if (!p(k, v)) { + this -= k + } + i += 1 + } + } + this + } + + @deprecated("Use mapValuesInPlace instead", "2.13.0") + @inline final def transform(f: (K, V) => V): this.type = mapValuesInPlace(f) + + /** Applies a transformation function to all values contained in this map. + * The transformation function produces new values from existing keys + * associated values. + * + * @param f the transformation to apply + * @return the map itself. + */ + def mapValuesInPlace(f: (K, V) => V): this.type = { + if (!isEmpty) this match { + case hm: mutable.HashMap[_, _] => hm.asInstanceOf[mutable.HashMap[K, V]].mapValuesInPlaceImpl(f) + case tm: concurrent.Map[_, _] => tm.asInstanceOf[concurrent.Map[K, V]].mapValuesInPlaceImpl(f) + case _ => + val array = this.toArray[Any] + val arrayLength = array.length + var i = 0 + while (i < arrayLength) { + val (k, v) = array(i).asInstanceOf[(K, V)] + update(k, f(k, v)) + i += 1 + } + } + this + } + + @deprecated("Use m.clone().addOne((k,v)) instead of m.updated(k, v)", "2.13.0") + def updated[V1 >: V](key: K, value: V1): CC[K, V1] = + clone().asInstanceOf[CC[K, V1]].addOne((key, value)) + + override def knownSize: Int = super[IterableOps].knownSize +} + +/** + * $factoryInfo + * @define coll mutable map + * @define Coll `mutable.Map` + */ +@SerialVersionUID(3L) +object Map extends MapFactory.Delegate[Map](HashMap) { + + @SerialVersionUID(3L) + class WithDefault[K, V](val underlying: Map[K, V], val defaultValue: K -> V) + extends AbstractMap[K, V] + with MapOps[K, V, Map, WithDefault[K, V]] with Serializable { + + override def default(key: K): V = defaultValue(key) + + def iterator: scala.collection.Iterator[(K, V)] = underlying.iterator + override def isEmpty: Boolean = underlying.isEmpty + override def knownSize: Int = underlying.knownSize + override def mapFactory: MapFactory[Map] = underlying.mapFactory + + override def clear(): Unit = underlying.clear() + + def get(key: K): Option[V] = underlying.get(key) + + def subtractOne(elem: K): WithDefault.this.type = { underlying.subtractOne(elem); this } + + def addOne(elem: (K, V)): WithDefault.this.type = { underlying.addOne(elem); this } + + override def concat[V2 >: V](suffix: collection.IterableOnce[(K, V2)]^): Map[K, V2] = + underlying.concat(suffix).withDefault(defaultValue) + + override def empty: WithDefault[K, V] = new WithDefault[K, V](underlying.empty, defaultValue) + + override protected def fromSpecific(coll: scala.collection.IterableOnce[(K, V)]^): WithDefault[K, V] = + new WithDefault[K, V](mapFactory.from(coll), defaultValue) + + override protected def newSpecificBuilder: Builder[(K, V), WithDefault[K, V]] = + Map.newBuilder.mapResult((p: Map[K, V]) => new WithDefault[K, V](p, defaultValue)) + } + +} + +/** Explicit instantiation of the `Map` trait to reduce class file size in subclasses. */ +abstract class AbstractMap[K, V] extends scala.collection.AbstractMap[K, V] with Map[K, V] From 3dc0eae125898e755604ff46e6ac025873e85d66 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 16:11:57 +0100 Subject: [PATCH 46/89] Add HashMaps to stdlib --- tests/pos-special/stdlib/collection/Seq.scala | 6 +- .../collection/StrictOptimizedSeqOps.scala | 5 +- .../stdlib/collection/mutable/HashMap.scala | 655 ++++++++++++++++++ .../collection/mutable/LinkedHashMap.scala | 510 ++++++++++++++ .../collection/mutable/LinkedHashSet.scala | 349 ++++++++++ 5 files changed, 1520 insertions(+), 5 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/mutable/HashMap.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/LinkedHashMap.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/LinkedHashSet.scala diff --git a/tests/pos-special/stdlib/collection/Seq.scala b/tests/pos-special/stdlib/collection/Seq.scala index 3a30906b467c..365a1db1b849 100644 --- a/tests/pos-special/stdlib/collection/Seq.scala +++ b/tests/pos-special/stdlib/collection/Seq.scala @@ -893,7 +893,7 @@ trait SeqOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { self => * part of the result, but any following occurrences will. */ def diff[B >: A](that: Seq[B]): C = { - val occ = occCounts(that) + val occ = occCounts[B @uncheckedCaptures](that) fromSpecific(iterator.filter { x => var include = false occ.updateWith(x) { @@ -918,7 +918,7 @@ trait SeqOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { self => * in the result, but any following occurrences will be omitted. */ def intersect[B >: A](that: Seq[B]): C = { - val occ = occCounts(that) + val occ = occCounts[B @uncheckedCaptures](that) fromSpecific(iterator.filter { x => var include = true occ.updateWith(x) { @@ -966,7 +966,7 @@ trait SeqOps[+A, +CC[_], +C] extends Any with SeqViewOps[A, CC, C] { self => iterableFactory.from(new View.Updated(this, index, elem)) } - protected[collection] def occCounts[B](sq: Seq[B]): mutable.Map[B, Int] = { + protected[collection] def occCounts[sealed B](sq: Seq[B]): mutable.Map[B, Int] = { val occ = new mutable.HashMap[B, Int]() for (y <- sq) occ.updateWith(y) { case None => Some(1) diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala index 50ddbca30f9e..14dea1694d09 100644 --- a/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala +++ b/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala @@ -12,6 +12,7 @@ package scala.collection import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures /** * Trait that overrides operations on sequences in order @@ -79,7 +80,7 @@ trait StrictOptimizedSeqOps [+A, +CC[_], +C] override def diff[B >: A](that: Seq[B]): C = if (isEmpty || that.isEmpty) coll else { - val occ = occCounts(that) + val occ = occCounts[B @uncheckedCaptures](that) val b = newSpecificBuilder for (x <- this) { occ.updateWith(x) { @@ -97,7 +98,7 @@ trait StrictOptimizedSeqOps [+A, +CC[_], +C] override def intersect[B >: A](that: Seq[B]): C = if (isEmpty || that.isEmpty) empty else { - val occ = occCounts(that) + val occ = occCounts[B @uncheckedCaptures](that) val b = newSpecificBuilder for (x <- this) { occ.updateWith(x) { diff --git a/tests/pos-special/stdlib/collection/mutable/HashMap.scala b/tests/pos-special/stdlib/collection/mutable/HashMap.scala new file mode 100644 index 000000000000..ab45e7ffc73d --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/HashMap.scala @@ -0,0 +1,655 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.annotation.{nowarn, tailrec} +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializationProxy +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking + +/** This class implements mutable maps using a hashtable. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#hash-tables "Scala's Collection Library overview"]] + * section on `Hash Tables` for more information. + * + * @tparam K the type of the keys contained in this hash map. + * @tparam V the type of the values assigned to keys in this hash map. + * + * @define Coll `mutable.HashMap` + * @define coll mutable hash map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@deprecatedInheritance("HashMap will be made final; use .withDefault for the common use case of computing a default value", "2.13.0") +class HashMap[sealed K, sealed V](initialCapacity: Int, loadFactor: Double) + extends AbstractMap[K, V] + with MapOps[K, V, HashMap, HashMap[K, V]] + with StrictOptimizedIterableOps[(K, V), Iterable, HashMap[K, V]] + with StrictOptimizedMapOps[K, V, HashMap, HashMap[K, V]] + with MapFactoryDefaults[K, V, HashMap, Iterable] + with Serializable { + + /* The HashMap class holds the following invariant: + * - For each i between 0 and table.length, the bucket at table(i) only contains keys whose hash-index is i. + * - Every bucket is sorted in ascendent hash order + * - The sum of the lengths of all buckets is equal to contentSize. + */ + def this() = this(HashMap.defaultInitialCapacity, HashMap.defaultLoadFactor) + + import HashMap.Node + + /** The actual hash table. */ + private[this] var table = new Array[Node[K, V]](tableSizeFor(initialCapacity)) + + /** The next size value at which to resize (capacity * load factor). */ + private[this] var threshold: Int = newThreshold(table.length) + + private[this] var contentSize = 0 + + override def size: Int = contentSize + + /** Performs the inverse operation of improveHash. In this case, it happens to be identical to improveHash*/ + @`inline` private[collection] def unimproveHash(improvedHash: Int): Int = improveHash(improvedHash) + + /** Computes the improved hash of an original (`any.##`) hash. */ + @`inline` private[this] def improveHash(originalHash: Int): Int = { + // Improve the hash by xoring the high 16 bits into the low 16 bits just in case entropy is skewed towards the + // high-value bits. We only use the lowest bits to determine the hash bucket. This is the same improvement + // algorithm as in java.util.HashMap. + // + // This function is also its own inverse. That is, for all ints i, improveHash(improveHash(i)) = i + // this allows us to retrieve the original hash when we need it, for instance when appending to an immutable.HashMap + // and that is why unimproveHash simply forwards to this method + originalHash ^ (originalHash >>> 16) + } + + /** Computes the improved hash of this key */ + @`inline` private[this] def computeHash(o: K): Int = improveHash(o.##) + + @`inline` private[this] def index(hash: Int) = hash & (table.length - 1) + + override def contains(key: K): Boolean = findNode(key) ne null + + @`inline` private[this] def findNode(key: K): Node[K, V] = { + val hash = computeHash(key) + table(index(hash)) match { + case null => null + case nd => nd.findNode(key, hash) + } + } + + override def sizeHint(size: Int): Unit = { + val target = tableSizeFor(((size + 1).toDouble / loadFactor).toInt) + if(target > table.length) growTable(target) + } + + override def addAll(xs: IterableOnce[(K, V)]^): this.type = { + sizeHint(xs.knownSize) + + xs match { + case hm: immutable.HashMap[K, V] => + hm.foreachWithHash((k, v, h) => put0(k, v, improveHash(h), getOld = false)) + this + case hm: mutable.HashMap[K, V] => + val iter = hm.nodeIterator + while (iter.hasNext) { + val next = iter.next() + put0(next.key, next.value, next.hash, getOld = false) + } + this + case lhm: mutable.LinkedHashMap[K, V] => + val iter = lhm.entryIterator + while (iter.hasNext) { + val entry = iter.next() + put0(entry.key, entry.value, entry.hash, getOld = false) + } + this + case thatMap: Map[K, V] => + thatMap.foreachEntry { (key: K, value: V) => + put0(key, value, improveHash(key.##), getOld = false) + } + this + case _ => + super.addAll(xs) + } + } + + // Override updateWith for performance, so we can do the update while hashing + // the input key only once and performing one lookup into the hash table + override def updateWith(key: K)(remappingFunction: Option[V] => Option[V]): Option[V] = { + if (getClass != classOf[HashMap[_, _]]) { + // subclasses of HashMap might customise `get` ... + super.updateWith(key)(remappingFunction) + } else { + val hash = computeHash(key) + val indexedHash = index(hash) + + var foundNode: Node[K, V] = null + var previousNode: Node[K, V] = null + table(indexedHash) match { + case null => + case nd => + @tailrec + def findNode(prev: Node[K, V], nd: Node[K, V], k: K, h: Int): Unit = { + if (h == nd.hash && k == nd.key) { + previousNode = prev + foundNode = nd + } + else if ((nd.next eq null) || (nd.hash > h)) () + else findNode(nd, nd.next, k, h) + } + + findNode(null, nd, key, hash) + } + + val previousValue = foundNode match { + case null => None + case nd => Some(nd.value) + } + + val nextValue = remappingFunction(previousValue) + + (previousValue, nextValue) match { + case (None, None) => // do nothing + + case (Some(_), None) => + if (previousNode != null) previousNode.next = foundNode.next + else table(indexedHash) = foundNode.next + contentSize -= 1 + + case (None, Some(value)) => + val newIndexedHash = + if (contentSize + 1 >= threshold) { + growTable(table.length * 2) + index(hash) + } else indexedHash + put0(key, value, false, hash, newIndexedHash) + + case (Some(_), Some(newValue)) => foundNode.value = newValue + } + nextValue + } + } + + override def subtractAll(xs: IterableOnce[K]^): this.type = { + if (size == 0) { + return this + } + + xs match { + case hs: immutable.HashSet[K] => + hs.foreachWithHashWhile { (k, h) => + remove0(k, improveHash(h)) + size > 0 + } + this + case hs: mutable.HashSet[K] => + val iter = hs.nodeIterator + while (iter.hasNext) { + val next = iter.next() + remove0(next.key, next.hash) + if (size == 0) return this + } + this + case lhs: mutable.LinkedHashSet[K] => + val iter = lhs.entryIterator + while (iter.hasNext) { + val next = iter.next() + remove0(next.key, next.hash) + if (size == 0) return this + } + this + case _ => super.subtractAll(xs) + } + } + + /** Adds a key-value pair to this map + * + * @param key the key to add + * @param value the value to add + * @param hash the **improved** hashcode of `key` (see computeHash) + * @param getOld if true, then the previous value for `key` will be returned, otherwise, false + */ + private[this] def put0(key: K, value: V, hash: Int, getOld: Boolean): Some[V] = { + if(contentSize + 1 >= threshold) growTable(table.length * 2) + val idx = index(hash) + put0(key, value, getOld, hash, idx) + } + + private[this] def put0(key: K, value: V, getOld: Boolean): Some[V] = { + if(contentSize + 1 >= threshold) growTable(table.length * 2) + val hash = computeHash(key) + val idx = index(hash) + put0(key, value, getOld, hash, idx) + } + + + private[this] def put0(key: K, value: V, getOld: Boolean, hash: Int, idx: Int): Some[V] = { + table(idx) match { + case null => + table(idx) = new Node[K, V](key, hash, value, null) + case old => + var prev: Node[K, V] = null + var n = old + while((n ne null) && n.hash <= hash) { + if(n.hash == hash && key == n.key) { + val old = n.value + n.value = value + return if(getOld) Some(old) else null + } + prev = n + n = n.next + } + if(prev eq null) table(idx) = new Node(key, hash, value, old) + else prev.next = new Node(key, hash, value, prev.next) + } + contentSize += 1 + null + } + + private def remove0(elem: K) : Node[K, V] = remove0(elem, computeHash(elem)) + + /** Removes a key from this map if it exists + * + * @param elem the element to remove + * @param hash the **improved** hashcode of `element` (see computeHash) + * @return the node that contained element if it was present, otherwise null + */ + private[this] def remove0(elem: K, hash: Int) : Node[K, V] = { + val idx = index(hash) + table(idx) match { + case null => null + case nd if nd.hash == hash && nd.key == elem => + // first element matches + table(idx) = nd.next + contentSize -= 1 + nd + case nd => + // find an element that matches + var prev = nd + var next = nd.next + while((next ne null) && next.hash <= hash) { + if(next.hash == hash && next.key == elem) { + prev.next = next.next + contentSize -= 1 + return next + } + prev = next + next = next.next + } + null + } + } + + private[this] abstract class HashMapIterator[A] extends AbstractIterator[A] { + private[this] var i = 0 + private[this] var node: Node[K, V] = null + private[this] val len = table.length + + protected[this] def extract(nd: Node[K, V]): A + + def hasNext: Boolean = { + if(node ne null) true + else { + while(i < len) { + val n = table(i) + i += 1 + if(n ne null) { node = n; return true } + } + false + } + } + + def next(): A = + if(!hasNext) Iterator.empty.next() + else { + val r = extract(node) + node = node.next + r + } + } + + override def iterator: Iterator[(K, V)] = + if(size == 0) Iterator.empty + else new HashMapIterator[(K, V)] { + protected[this] def extract(nd: Node[K, V]) = (nd.key, nd.value) + } + + override def keysIterator: Iterator[K] = + if(size == 0) Iterator.empty + else new HashMapIterator[K] { + protected[this] def extract(nd: Node[K, V]) = nd.key + } + + override def valuesIterator: Iterator[V] = + if(size == 0) Iterator.empty + else new HashMapIterator[V] { + protected[this] def extract(nd: Node[K, V]) = nd.value + } + + + /** Returns an iterator over the nodes stored in this HashMap */ + private[collection] def nodeIterator: Iterator[Node[K, V]] = + if(size == 0) Iterator.empty + else new HashMapIterator[Node[K, V]] { + protected[this] def extract(nd: Node[K, V]) = nd + } + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[(K, V), S]): S with EfficientSplit = + shape. + parUnbox(new convert.impl.AnyTableStepper[(K, V), Node[K, V]](size, table, _.next, node => (node.key, node.value), 0, table.length)). + asInstanceOf[S with EfficientSplit] + + override def keyStepper[S <: Stepper[_]](implicit shape: StepperShape[K, S]): S with EfficientSplit = { + import convert.impl._ + val s = shape.shape match { + case StepperShape.IntShape => new IntTableStepper[Node[K, V]] (size, table, _.next, _.key.asInstanceOf[Int], 0, table.length) + case StepperShape.LongShape => new LongTableStepper[Node[K, V]] (size, table, _.next, _.key.asInstanceOf[Long], 0, table.length) + case StepperShape.DoubleShape => new DoubleTableStepper[Node[K, V]](size, table, _.next, _.key.asInstanceOf[Double], 0, table.length) + case _ => shape.parUnbox(new AnyTableStepper[K, Node[K, V]](size, table, _.next, _.key, 0, table.length)) + } + s.asInstanceOf[S with EfficientSplit] + } + + override def valueStepper[S <: Stepper[_]](implicit shape: StepperShape[V, S]): S with EfficientSplit = { + import convert.impl._ + val s = shape.shape match { + case StepperShape.IntShape => new IntTableStepper[Node[K, V]] (size, table, _.next, _.value.asInstanceOf[Int], 0, table.length) + case StepperShape.LongShape => new LongTableStepper[Node[K, V]] (size, table, _.next, _.value.asInstanceOf[Long], 0, table.length) + case StepperShape.DoubleShape => new DoubleTableStepper[Node[K, V]](size, table, _.next, _.value.asInstanceOf[Double], 0, table.length) + case _ => shape.parUnbox(new AnyTableStepper[V, Node[K, V]](size, table, _.next, _.value, 0, table.length)) + } + s.asInstanceOf[S with EfficientSplit] + } + + private[this] def growTable(newlen: Int) = { + if (newlen < 0) + throw new RuntimeException(s"new HashMap table size $newlen exceeds maximum") + var oldlen = table.length + threshold = newThreshold(newlen) + if(size == 0) table = new Array(newlen) + else { + table = java.util.Arrays.copyOf(table, newlen) + val preLow: Node[K, V] = new Node(null.asInstanceOf[K], 0, null.asInstanceOf[V], null) + val preHigh: Node[K, V] = new Node(null.asInstanceOf[K], 0, null.asInstanceOf[V], null) + // Split buckets until the new length has been reached. This could be done more + // efficiently when growing an already filled table to more than double the size. + while(oldlen < newlen) { + var i = 0 + while (i < oldlen) { + val old = table(i) + if(old ne null) { + preLow.next = null + preHigh.next = null + var lastLow: Node[K, V] = preLow + var lastHigh: Node[K, V] = preHigh + var n = old + while(n ne null) { + val next = n.next + if((n.hash & oldlen) == 0) { // keep low + lastLow.next = n + lastLow = n + } else { // move to high + lastHigh.next = n + lastHigh = n + } + n = next + } + lastLow.next = null + if(old ne preLow.next) table(i) = preLow.next + if(preHigh.next ne null) { + table(i + oldlen) = preHigh.next + lastHigh.next = null + } + } + i += 1 + } + oldlen *= 2 + } + } + } + + private[this] def tableSizeFor(capacity: Int) = + (Integer.highestOneBit((capacity-1).max(4))*2).min(1 << 30) + + private[this] def newThreshold(size: Int) = (size.toDouble * loadFactor).toInt + + override def clear(): Unit = { + java.util.Arrays.fill(table.asInstanceOf[Array[AnyRef]], null) + contentSize = 0 + } + + def get(key: K): Option[V] = findNode(key) match { + case null => None + case nd => Some(nd.value) + } + + @throws[NoSuchElementException] + override def apply(key: K): V = findNode(key) match { + case null => default(key) + case nd => nd.value + } + + override def getOrElse[V1 >: V](key: K, default: => V1): V1 = { + if (getClass != classOf[HashMap[_, _]]) { + // subclasses of HashMap might customise `get` ... + super.getOrElse(key, default) + } else { + // .. but in the common case, we can avoid the Option boxing. + val nd = findNode(key) + if (nd eq null) default else nd.value + } + } + + override def getOrElseUpdate(key: K, defaultValue: => V): V = { + if (getClass != classOf[HashMap[_, _]]) { + // subclasses of HashMap might customise `get` ... + super.getOrElseUpdate(key, defaultValue) + } else { + val hash = computeHash(key) + val idx = index(hash) + val nd = table(idx) match { + case null => null + case nd => nd.findNode(key, hash) + } + if(nd != null) nd.value + else { + val table0 = table + val default = defaultValue + if(contentSize + 1 >= threshold) growTable(table.length * 2) + // Avoid recomputing index if the `defaultValue()` or new element hasn't triggered a table resize. + val newIdx = if (table0 eq table) idx else index(hash) + put0(key, default, false, hash, newIdx) + default + } + } + } + + override def put(key: K, value: V): Option[V] = put0(key, value, true) match { + case null => None + case sm => sm + } + + override def remove(key: K): Option[V] = remove0(key) match { + case null => None + case nd => Some(nd.value) + } + + override def update(key: K, value: V): Unit = put0(key, value, false) + + def addOne(elem: (K, V)): this.type = { put0(elem._1, elem._2, false); this } + + def subtractOne(elem: K): this.type = { remove0(elem); this } + + override def knownSize: Int = size + + override def isEmpty: Boolean = size == 0 + + override def foreach[U](f: ((K, V)) => U): Unit = { + val len = table.length + var i = 0 + while(i < len) { + val n = table(i) + if(n ne null) n.foreach(f) + i += 1 + } + } + + override def foreachEntry[U](f: (K, V) => U): Unit = { + val len = table.length + var i = 0 + while(i < len) { + val n = table(i) + if(n ne null) n.foreachEntry(f) + i += 1 + } + } + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(new mutable.HashMap.DeserializationFactory[K, V](table.length, loadFactor), this) + + override def filterInPlace(p: (K, V) => Boolean): this.type = { + if (nonEmpty) { + var bucket = 0 + + while (bucket < table.length) { + var head = table(bucket) + + while ((head ne null) && !p(head.key, head.value)) { + head = head.next + contentSize -= 1 + } + + if (head ne null) { + var prev = head + var next = head.next + + while (next ne null) { + if (p(next.key, next.value)) { + prev = next + } else { + prev.next = next.next + contentSize -= 1 + } + next = next.next + } + } + + table(bucket) = head + bucket += 1 + } + } + this + } + + // TODO: rename to `mapValuesInPlace` and override the base version (not binary compatible) + private[mutable] def mapValuesInPlaceImpl(f: (K, V) => V): this.type = { + val len = table.length + var i = 0 + while (i < len) { + var n = table(i) + while (n ne null) { + n.value = f(n.key, n.value) + n = n.next + } + i += 1 + } + this + } + + override def mapFactory: MapFactory[HashMap] = HashMap + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "HashMap" + + override def hashCode: Int = { + if (isEmpty) MurmurHash3.emptyMapHash + else { + val tupleHashIterator = new HashMapIterator[Any] { + var hash: Int = 0 + override def hashCode: Int = hash + override protected[this] def extract(nd: Node[K, V]): Any = { + hash = MurmurHash3.tuple2Hash(unimproveHash(nd.hash), nd.value.##) + this + } + } + MurmurHash3.unorderedHash(tupleHashIterator, MurmurHash3.mapSeed) + } + } +} + +/** + * $factoryInfo + * @define Coll `mutable.HashMap` + * @define coll mutable hash map + */ +@SerialVersionUID(3L) +object HashMap extends MapFactory[HashMap] { + + def empty[sealed K, sealed V]: HashMap[K, V] = new HashMap[K, V] + + def from[sealed K, sealed V](it: collection.IterableOnce[(K, V)]^): HashMap[K, V] = { + val k = it.knownSize + val cap = if(k > 0) ((k + 1).toDouble / defaultLoadFactor).toInt else defaultInitialCapacity + new HashMap[K, V](cap, defaultLoadFactor).addAll(it) + } + + def newBuilder[sealed K, sealed V]: Builder[(K, V), HashMap[K, V]] = newBuilder(defaultInitialCapacity, defaultLoadFactor) + + def newBuilder[sealed K, sealed V](initialCapacity: Int, loadFactor: Double): Builder[(K, V), HashMap[K, V]] = + new GrowableBuilder[(K, V), HashMap[K, V]](new HashMap[K, V](initialCapacity, loadFactor)) { + override def sizeHint(size: Int) = elems.sizeHint(size) + } + + /** The default load factor for the hash table */ + final def defaultLoadFactor: Double = 0.75 + + /** The default initial capacity for the hash table */ + final def defaultInitialCapacity: Int = 16 + + @SerialVersionUID(3L) + private final class DeserializationFactory[sealed K, sealed V](val tableLength: Int, val loadFactor: Double) extends Factory[(K, V), HashMap[K, V]] with Serializable { + def fromSpecific(it: IterableOnce[(K, V)]^): HashMap[K, V] = new HashMap[K, V](tableLength, loadFactor).addAll(it) + def newBuilder: Builder[(K, V), HashMap[K, V]] = HashMap.newBuilder(tableLength, loadFactor) + } + + private[collection] final class Node[K, V](_key: K, _hash: Int, private[this] var _value: V, private[this] var _next: Node[K, V]) { + def key: K = _key + def hash: Int = _hash + def value: V = _value + def value_= (v: V): Unit = _value = v + def next: Node[K, V] = _next + def next_= (n: Node[K, V]): Unit = _next = n + + @tailrec + def findNode(k: K, h: Int): Node[K, V] = + if(h == _hash && k == _key) this + else if((_next eq null) || (_hash > h)) null + else _next.findNode(k, h) + + @tailrec + def foreach[U](f: ((K, V)) => U): Unit = { + f((_key, _value)) + if(_next ne null) _next.foreach(f) + } + + @tailrec + def foreachEntry[U](f: (K, V) => U): Unit = { + f(_key, _value) + if(_next ne null) _next.foreachEntry(f) + } + + override def toString = s"Node($key, $value, $hash) -> $next" + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/LinkedHashMap.scala b/tests/pos-special/stdlib/collection/mutable/LinkedHashMap.scala new file mode 100644 index 000000000000..a253e8738b26 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/LinkedHashMap.scala @@ -0,0 +1,510 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.annotation.{nowarn, tailrec} +import scala.collection.generic.DefaultSerializable +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking + + +/** This class implements mutable maps using a hashtable. + * The iterator and all traversal methods of this class visit elements in the order they were inserted. + * + * @tparam K the type of the keys contained in this hash map. + * @tparam V the type of the values assigned to keys in this hash map. + * + * @define Coll `LinkedHashMap` + * @define coll linked hash map + * @define mayNotTerminateInf + * @define willNotTerminateInf + * @define orderDependent + * @define orderDependentFold + */ +@deprecatedInheritance("LinkedHashMap will be made final; use .withDefault for the common use case of computing a default value", "2.13.11") +class LinkedHashMap[sealed K, sealed V] + extends AbstractMap[K, V] + with SeqMap[K, V] + with MapOps[K, V, LinkedHashMap, LinkedHashMap[K, V]] + with StrictOptimizedIterableOps[(K, V), Iterable, LinkedHashMap[K, V]] + with StrictOptimizedMapOps[K, V, LinkedHashMap, LinkedHashMap[K, V]] + with MapFactoryDefaults[K, V, LinkedHashMap, Iterable] + with DefaultSerializable { + + override def mapFactory: MapFactory[LinkedHashMap] = LinkedHashMap + + // stepper / keyStepper / valueStepper are not overridden to use XTableStepper because that stepper + // would not return the elements in insertion order + + private[collection] type Entry = LinkedHashMap.LinkedEntry[K, V] + + private[collection] def _firstEntry: Entry = firstEntry + + protected var firstEntry: Entry = null + + protected var lastEntry: Entry = null + + /* Uses the same implementation as mutable.HashMap. The hashtable holds the following invariant: + * - For each i between 0 and table.length, the bucket at table(i) only contains keys whose hash-index is i. + * - Every bucket is sorted in ascendant hash order + * - The sum of the lengths of all buckets is equal to contentSize. + */ + private[this] var table = new Array[Entry](tableSizeFor(LinkedHashMap.defaultinitialSize)) + + private[this] var threshold: Int = newThreshold(table.length) + + private[this] var contentSize = 0 + + override def last: (K, V) = + if (size > 0) (lastEntry.key, lastEntry.value) + else throw new NoSuchElementException("Cannot call .last on empty LinkedHashMap") + + override def lastOption: Option[(K, V)] = + if (size > 0) Some((lastEntry.key, lastEntry.value)) + else None + + override def head: (K, V) = + if (size > 0) (firstEntry.key, firstEntry.value) + else throw new NoSuchElementException("Cannot call .head on empty LinkedHashMap") + + override def headOption: Option[(K, V)] = + if (size > 0) Some((firstEntry.key, firstEntry.value)) + else None + + override def size = contentSize + override def knownSize: Int = size + override def isEmpty: Boolean = size == 0 + + def get(key: K): Option[V] = { + val e = findEntry(key) + if (e == null) None + else Some(e.value) + } + override def sizeHint(size: Int): Unit = { + val target = tableSizeFor(((size + 1).toDouble / LinkedHashMap.defaultLoadFactor).toInt) + if (target > table.length) growTable(target) + } + + override def contains(key: K): Boolean = { + if (getClass eq classOf[LinkedHashMap[_, _]]) + findEntry(key) != null + else + super.contains(key) // A subclass might override `get`, use the default implementation `contains`. + } + + override def put(key: K, value: V): Option[V] = put0(key, value, true) match { + case null => None + case sm => sm + } + + override def update(key: K, value: V): Unit = put0(key, value, false) + + override def remove(key: K): Option[V] = removeEntry0(key) match { + case null => None + case nd => Some(nd.value) + } + + override def getOrElse[V1 >: V](key: K, default: => V1): V1 = { + if (getClass != classOf[LinkedHashMap[_, _]]) { + // subclasses of LinkedHashMap might customise `get` ... + super.getOrElse(key, default) + } else { + // .. but in the common case, we can avoid the Option boxing. + val nd = findEntry(key) + if (nd eq null) default else nd.value + } + } + + override def getOrElseUpdate(key: K, defaultValue: => V): V = { + if (getClass != classOf[LinkedHashMap[_, _]]) { + // subclasses of LinkedHashMap might customise `get` ... + super.getOrElseUpdate(key, defaultValue) + } else { + val hash = computeHash(key) + val idx = index(hash) + val nd = table(idx) match { + case null => null + case nd => nd.findEntry(key, hash) + } + if (nd != null) nd.value + else { + val table0 = table + val default = defaultValue + if (contentSize + 1 >= threshold) growTable(table.length * 2) + // Avoid recomputing index if the `defaultValue()` or new element hasn't triggered a table resize. + val newIdx = if (table0 eq table) idx else index(hash) + put0(key, default, false, hash, newIdx) + default + } + } + } + + private[this] def removeEntry0(elem: K): Entry = removeEntry0(elem, computeHash(elem)) + + /** Removes a key from this map if it exists + * + * @param elem the element to remove + * @param hash the **improved** hashcode of `element` (see computeHash) + * @return the node that contained element if it was present, otherwise null + */ + private[this] def removeEntry0(elem: K, hash: Int): Entry = { + val idx = index(hash) + table(idx) match { + case null => null + case nd if nd.hash == hash && nd.key == elem => + // first element matches + table(idx) = nd.next + deleteEntry(nd) + contentSize -= 1 + nd + case nd => + // find an element that matches + var prev = nd + var next = nd.next + while ((next ne null) && next.hash <= hash) { + if (next.hash == hash && next.key == elem) { + prev.next = next.next + deleteEntry(next) + contentSize -= 1 + return next + } + prev = next + next = next.next + } + null + } + } + + /** Computes the improved hash of an original (`any.##`) hash. */ + @`inline` private[this] def improveHash(originalHash: Int): Int = { + originalHash ^ (originalHash >>> 16) + } + @`inline` private[collection] def unimproveHash(improvedHash: Int): Int = improveHash(improvedHash) + + /** Computes the improved hash of this key */ + @`inline` private[this] def computeHash(o: K): Int = improveHash(o.##) + + @`inline` private[this] def index(hash: Int) = hash & (table.length - 1) + + @`inline` private[this] def findEntry(key: K): Entry = { + val hash = computeHash(key) + table(index(hash)) match { + case null => null + case nd => nd.findEntry(key, hash) + } + } + + def addOne(kv: (K, V)): this.type = { + put(kv._1, kv._2) + this + } + + def subtractOne(key: K): this.type = { + remove(key) + this + } + + private[this] abstract class LinkedHashMapIterator[T] extends AbstractIterator[T] { + private[this] var cur = firstEntry + def extract(nd: Entry): T + def hasNext: Boolean = cur ne null + def next(): T = + if (hasNext) { val r = extract(cur); cur = cur.later; r } + else Iterator.empty.next() + } + + def iterator: Iterator[(K, V)] = + if (size == 0) Iterator.empty + else new LinkedHashMapIterator[(K, V)] { + def extract(nd: Entry): (K, V) = (nd.key, nd.value) + } + + protected class LinkedKeySet extends KeySet { + override def iterableFactory: IterableFactory[collection.Set] = LinkedHashSet + } + + override def keySet: collection.Set[K] = new LinkedKeySet + + override def keysIterator: Iterator[K] = + if (size == 0) Iterator.empty + else new LinkedHashMapIterator[K] { + def extract(nd: Entry): K = nd.key + } + + private[collection] def entryIterator: Iterator[Entry] = + if (size == 0) Iterator.empty + else new LinkedHashMapIterator[Entry] { + def extract(nd: Entry): Entry = nd + } + + + // Override updateWith for performance, so we can do the update while hashing + // the input key only once and performing one lookup into the hash table + override def updateWith(key: K)(remappingFunction: Option[V] => Option[V]): Option[V] = { + if (getClass != classOf[LinkedHashMap[_, _]]) { + // subclasses of LinkedHashMap might customise `get` ... + super.updateWith(key)(remappingFunction) + } else { + val hash = computeHash(key) + val indexedHash = index(hash) + + var foundEntry: Entry = null + var previousEntry: Entry = null + table(indexedHash) match { + case null => + case nd => + @tailrec + def findEntry(prev: Entry, nd: Entry, k: K, h: Int): Unit = { + if (h == nd.hash && k == nd.key) { + previousEntry = prev + foundEntry = nd + } + else if ((nd.next eq null) || (nd.hash > h)) () + else findEntry(nd, nd.next, k, h) + } + + findEntry(null, nd, key, hash) + } + + val previousValue = foundEntry match { + case null => None + case nd => Some(nd.value) + } + + val nextValue = remappingFunction(previousValue) + + (previousValue, nextValue) match { + case (None, None) => // do nothing + + case (Some(_), None) => + if (previousEntry != null) previousEntry.next = foundEntry.next + else table(indexedHash) = foundEntry.next + deleteEntry(foundEntry) + contentSize -= 1 + + case (None, Some(value)) => + val newIndexedHash = + if (contentSize + 1 >= threshold) { + growTable(table.length * 2) + index(hash) + } else indexedHash + put0(key, value, false, hash, newIndexedHash) + + case (Some(_), Some(newValue)) => foundEntry.value = newValue + } + nextValue + } + } + + override def valuesIterator: Iterator[V] = + if (size == 0) Iterator.empty + else new LinkedHashMapIterator[V] { + def extract(nd: Entry): V = nd.value + } + + + override def foreach[U](f: ((K, V)) => U): Unit = { + var cur = firstEntry + while (cur ne null) { + f((cur.key, cur.value)) + cur = cur.later + } + } + + override def foreachEntry[U](f: (K, V) => U): Unit = { + var cur = firstEntry + while (cur ne null) { + f(cur.key, cur.value) + cur = cur.later + } + } + + override def clear(): Unit = { + java.util.Arrays.fill(table.asInstanceOf[Array[AnyRef]], null) + contentSize = 0 + firstEntry = null + lastEntry = null + } + + private[this] def tableSizeFor(capacity: Int) = + (Integer.highestOneBit((capacity - 1).max(4)) * 2).min(1 << 30) + + private[this] def newThreshold(size: Int) = (size.toDouble * LinkedHashMap.defaultLoadFactor).toInt + + /*create a new entry. If table is empty(firstEntry is null), then the + * new entry will be the firstEntry. If not, just set the new entry to + * be the lastEntry. + * */ + private[this] def createNewEntry(key: K, hash: Int, value: V): Entry = { + val e = new Entry(key, hash, value) + if (firstEntry eq null) firstEntry = e + else { + lastEntry.later = e + e.earlier = lastEntry + } + lastEntry = e + e + } + + /** Delete the entry from the LinkedHashMap, set the `earlier` and `later` pointers correctly */ + private[this] def deleteEntry(e: Entry): Unit = { + if (e.earlier eq null) firstEntry = e.later + else e.earlier.later = e.later + if (e.later eq null) lastEntry = e.earlier + else e.later.earlier = e.earlier + e.earlier = null + e.later = null + e.next = null + } + + private[this] def put0(key: K, value: V, getOld: Boolean): Some[V] = { + if (contentSize + 1 >= threshold) growTable(table.length * 2) + val hash = computeHash(key) + val idx = index(hash) + put0(key, value, getOld, hash, idx) + } + + private[this] def put0(key: K, value: V, getOld: Boolean, hash: Int, idx: Int): Some[V] = { + table(idx) match { + case null => + table(idx) = createNewEntry(key, hash, value) + case old => + var prev: Entry = null + var n = old + while ((n ne null) && n.hash <= hash) { + if (n.hash == hash && key == n.key) { + val old = n.value + n.value = value + return if (getOld) Some(old) else null + } + prev = n + n = n.next + } + val nnode = createNewEntry(key, hash, value) + if (prev eq null) { + nnode.next = old + table(idx) = nnode + } else { + nnode.next = prev.next + prev.next = nnode + } + } + contentSize += 1 + null + } + + private[this] def growTable(newlen: Int): Unit = { + if (newlen < 0) + throw new RuntimeException(s"new hash table size $newlen exceeds maximum") + var oldlen = table.length + threshold = newThreshold(newlen) + if (size == 0) table = new Array(newlen) + else { + table = java.util.Arrays.copyOf(table, newlen) + val preLow = new Entry(null.asInstanceOf[K], 0, null.asInstanceOf[V]) + val preHigh = new Entry(null.asInstanceOf[K], 0, null.asInstanceOf[V]) + // Split buckets until the new length has been reached. This could be done more + // efficiently when growing an already filled table to more than double the size. + while (oldlen < newlen) { + var i = 0 + while (i < oldlen) { + val old = table(i) + if (old ne null) { + preLow.next = null + preHigh.next = null + var lastLow = preLow + var lastHigh = preHigh + var n = old + while (n ne null) { + val next = n.next + if ((n.hash & oldlen) == 0) { // keep low + lastLow.next = n + lastLow = n + } else { // move to high + lastHigh.next = n + lastHigh = n + } + n = next + } + lastLow.next = null + if (old ne preLow.next) table(i) = preLow.next + if (preHigh.next ne null) { + table(i + oldlen) = preHigh.next + lastHigh.next = null + } + } + i += 1 + } + oldlen *= 2 + } + } + } + + override def hashCode: Int = { + if (isEmpty) MurmurHash3.emptyMapHash + else { + val tupleHashIterator = new LinkedHashMapIterator[Any] { + var hash: Int = 0 + override def hashCode: Int = hash + override def extract(nd: Entry): Any = { + hash = MurmurHash3.tuple2Hash(unimproveHash(nd.hash), nd.value.##) + this + } + } + MurmurHash3.unorderedHash(tupleHashIterator, MurmurHash3.mapSeed) + } + } + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "LinkedHashMap" +} + +/** $factoryInfo + * @define Coll `LinkedHashMap` + * @define coll linked hash map + */ +@SerialVersionUID(3L) +object LinkedHashMap extends MapFactory[LinkedHashMap] { + + def empty[sealed K, sealed V] = new LinkedHashMap[K, V] + + def from[sealed K, sealed V](it: collection.IterableOnce[(K, V)]^) = { + val newlhm = empty[K, V] + newlhm.sizeHint(it.knownSize) + newlhm.addAll(it) + newlhm + } + + def newBuilder[sealed K, sealed V] = new GrowableBuilder(empty[K, V]) + + /** Class for the linked hash map entry, used internally. + */ + private[mutable] final class LinkedEntry[sealed K, sealed V](val key: K, val hash: Int, var value: V) { + var earlier: LinkedEntry[K, V] = null + var later: LinkedEntry[K, V] = null + var next: LinkedEntry[K, V] = null + + @tailrec + final def findEntry(k: K, h: Int): LinkedEntry[K, V] = + if (h == hash && k == key) this + else if ((next eq null) || (hash > h)) null + else next.findEntry(k, h) + } + + /** The default load factor for the hash table */ + private[collection] final def defaultLoadFactor: Double = 0.75 + + /** The default initial capacity for the hash table */ + private[collection] final def defaultinitialSize: Int = 16 +} diff --git a/tests/pos-special/stdlib/collection/mutable/LinkedHashSet.scala b/tests/pos-special/stdlib/collection/mutable/LinkedHashSet.scala new file mode 100644 index 000000000000..a895034a852c --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/LinkedHashSet.scala @@ -0,0 +1,349 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.annotation.{nowarn, tailrec} +import scala.collection.generic.DefaultSerializable +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking + +/** This class implements mutable sets using a hashtable. + * The iterator and all traversal methods of this class visit elements in the order they were inserted. + * + * @tparam A the type of the elements contained in this set. + * + * @define Coll `LinkedHashSet` + * @define coll linked hash set + * @define mayNotTerminateInf + * @define willNotTerminateInf + * @define orderDependent + * @define orderDependentFold + */ +@deprecatedInheritance("LinkedHashSet will be made final", "2.13.11") +class LinkedHashSet[sealed A] + extends AbstractSet[A] + with SetOps[A, LinkedHashSet, LinkedHashSet[A]] + with StrictOptimizedIterableOps[A, LinkedHashSet, LinkedHashSet[A]] + with IterableFactoryDefaults[A, LinkedHashSet] + with DefaultSerializable { + + override def iterableFactory: IterableFactory[LinkedHashSet] = LinkedHashSet + + // stepper is not overridden to use XTableStepper because that stepper would not return the + // elements in insertion order + + /*private*/ type Entry = LinkedHashSet.Entry[A] + + protected var firstEntry: Entry = null + + protected var lastEntry: Entry = null + + /* Uses the same implementation as mutable.HashSet. The hashtable holds the following invariant: + * - For each i between 0 and table.length, the bucket at table(i) only contains keys whose hash-index is i. + * - Every bucket is sorted in ascendant hash order + * - The sum of the lengths of all buckets is equal to contentSize. + */ + private[this] var table = new Array[Entry](tableSizeFor(LinkedHashSet.defaultinitialSize)) + + private[this] var threshold: Int = newThreshold(table.length) + + private[this] var contentSize = 0 + + override def last: A = + if (size > 0) lastEntry.key + else throw new NoSuchElementException("Cannot call .last on empty LinkedHashSet") + + override def lastOption: Option[A] = + if (size > 0) Some(lastEntry.key) + else None + + override def head: A = + if (size > 0) firstEntry.key + else throw new NoSuchElementException("Cannot call .head on empty LinkedHashSet") + + override def headOption: Option[A] = + if (size > 0) Some(firstEntry.key) + else None + + override def size: Int = contentSize + override def knownSize: Int = size + override def isEmpty: Boolean = size == 0 + + def contains(elem: A): Boolean = findEntry(elem) ne null + + override def sizeHint(size: Int): Unit = { + val target = tableSizeFor(((size + 1).toDouble / LinkedHashSet.defaultLoadFactor).toInt) + if (target > table.length) growTable(target) + } + + override def add(elem: A): Boolean = { + if (contentSize + 1 >= threshold) growTable(table.length * 2) + val hash = computeHash(elem) + put0(elem, hash, index(hash)) + } + + def addOne(elem: A): this.type = { + add(elem) + this + } + + def subtractOne(elem: A): this.type = { + remove(elem) + this + } + + override def remove(elem: A): Boolean = remove0(elem, computeHash(elem)) + + private[this] abstract class LinkedHashSetIterator[T] extends AbstractIterator[T] { + private[this] var cur = firstEntry + def extract(nd: Entry): T + def hasNext: Boolean = cur ne null + def next(): T = + if (hasNext) { val r = extract(cur); cur = cur.later; r } + else Iterator.empty.next() + } + + def iterator: Iterator[A] = new LinkedHashSetIterator[A] { + override def extract(nd: Entry): A = nd.key + } + + private[collection] def entryIterator: Iterator[Entry] = new LinkedHashSetIterator[Entry] { + override def extract(nd: Entry): Entry = nd + } + + override def foreach[U](f: A => U): Unit = { + var cur = firstEntry + while (cur ne null) { + f(cur.key) + cur = cur.later + } + } + + override def clear(): Unit = { + java.util.Arrays.fill(table.asInstanceOf[Array[AnyRef]], null) + contentSize = 0 + firstEntry = null + lastEntry = null + } + + private[this] def tableSizeFor(capacity: Int) = + (Integer.highestOneBit((capacity - 1).max(4)) * 2).min(1 << 30) + + private[this] def newThreshold(size: Int) = (size.toDouble * LinkedHashSet.defaultLoadFactor).toInt + + @`inline` private[this] def improveHash(originalHash: Int): Int = { + originalHash ^ (originalHash >>> 16) + } + + @`inline` private[collection] def unimproveHash(improvedHash: Int): Int = improveHash(improvedHash) + + /** Computes the improved hash of this key */ + @`inline` private[this] def computeHash(o: A): Int = improveHash(o.##) + + @`inline` private[this] def index(hash: Int) = hash & (table.length - 1) + + @`inline` private[this] def findEntry(key: A): Entry = { + val hash = computeHash(key) + table(index(hash)) match { + case null => null + case nd => nd.findEntry(key, hash) + } + } + + /*create a new entry. If table is empty(firstEntry is null), then the + * new entry will be the firstEntry. If not, just set the new entry to + * be the lastEntry. + * */ + private[this] def createNewEntry(key: A, hash: Int): Entry = { + val e = new Entry(key, hash) + if (firstEntry eq null) firstEntry = e + else { + lastEntry.later = e + e.earlier = lastEntry + } + lastEntry = e + e + } + + /** Delete the entry from the LinkedHashSet, set the `earlier` and `later` pointers correctly */ + private[this] def deleteEntry(e: Entry): Unit = { + if (e.earlier eq null) firstEntry = e.later + else e.earlier.later = e.later + if (e.later eq null) lastEntry = e.earlier + else e.later.earlier = e.earlier + e.earlier = null + e.later = null + e.next = null + } + + private[this] def put0(elem: A, hash: Int, idx: Int): Boolean = { + table(idx) match { + case null => + table(idx) = createNewEntry(elem, hash) + case old => + var prev: Entry = null + var n = old + while ((n ne null) && n.hash <= hash) { + if (n.hash == hash && elem == n.key) return false + prev = n + n = n.next + } + val nnode = createNewEntry(elem, hash) + if (prev eq null) { + nnode.next = old + table(idx) = nnode + } else { + nnode.next = prev.next + prev.next = nnode + } + } + contentSize += 1 + true + } + + private[this] def remove0(elem: A, hash: Int): Boolean = { + val idx = index(hash) + table(idx) match { + case null => false + case nd if nd.hash == hash && nd.key == elem => + // first element matches + table(idx) = nd.next + deleteEntry(nd) + contentSize -= 1 + true + case nd => + // find an element that matches + var prev = nd + var next = nd.next + while ((next ne null) && next.hash <= hash) { + if (next.hash == hash && next.key == elem) { + prev.next = next.next + deleteEntry(next) + contentSize -= 1 + return true + } + prev = next + next = next.next + } + false + } + } + + private[this] def growTable(newlen: Int): Unit = { + if (newlen < 0) + throw new RuntimeException(s"new hash table size $newlen exceeds maximum") + var oldlen = table.length + threshold = newThreshold(newlen) + if (size == 0) table = new Array(newlen) + else { + table = java.util.Arrays.copyOf(table, newlen) + val preLow = new Entry(null.asInstanceOf[A], 0) + val preHigh = new Entry(null.asInstanceOf[A], 0) + // Split buckets until the new length has been reached. This could be done more + // efficiently when growing an already filled table to more than double the size. + while (oldlen < newlen) { + var i = 0 + while (i < oldlen) { + val old = table(i) + if (old ne null) { + preLow.next = null + preHigh.next = null + var lastLow = preLow + var lastHigh = preHigh + var n = old + while (n ne null) { + val next = n.next + if ((n.hash & oldlen) == 0) { // keep low + lastLow.next = n + lastLow = n + } else { // move to high + lastHigh.next = n + lastHigh = n + } + n = next + } + lastLow.next = null + if (old ne preLow.next) table(i) = preLow.next + if (preHigh.next ne null) { + table(i + oldlen) = preHigh.next + lastHigh.next = null + } + } + i += 1 + } + oldlen *= 2 + } + } + } + + override def hashCode: Int = { + val setHashIterator = + if (isEmpty) this.iterator + else { + new LinkedHashSetIterator[Any] { + var hash: Int = 0 + override def hashCode: Int = hash + override def extract(nd: Entry): Any = { + hash = unimproveHash(nd.hash) + this + } + } + } + MurmurHash3.unorderedHash(setHashIterator, MurmurHash3.setSeed) + } + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "LinkedHashSet" +} + +/** $factoryInfo + * @define Coll `LinkedHashSet` + * @define coll linked hash set + */ +@SerialVersionUID(3L) +object LinkedHashSet extends IterableFactory[LinkedHashSet] { + + override def empty[sealed A]: LinkedHashSet[A] = new LinkedHashSet[A] + + def from[sealed E](it: collection.IterableOnce[E]^) = { + val newlhs = empty[E] + newlhs.sizeHint(it.knownSize) + newlhs.addAll(it) + newlhs + } + + def newBuilder[sealed A] = new GrowableBuilder(empty[A]) + + /** Class for the linked hash set entry, used internally. + */ + private[mutable] final class Entry[sealed A](val key: A, val hash: Int) { + var earlier: Entry[A] = null + var later: Entry[A] = null + var next: Entry[A] = null + + @tailrec + final def findEntry(k: A, h: Int): Entry[A] = + if (h == hash && k == key) this + else if ((next eq null) || (hash > h)) null + else next.findEntry(k, h) + } + + /** The default load factor for the hash table */ + private[collection] final def defaultLoadFactor: Double = 0.75 + + /** The default initial capacity for the hash table */ + private[collection] final def defaultinitialSize: Int = 16 +} + From 20f3a97dd68b0e7bd528a6bb764f0b6b421464c8 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 16:30:26 +0100 Subject: [PATCH 47/89] Add LongMap + friends to stdlib --- .../collection/mutable/ImmutableBuilder.scala | 32 + .../stdlib/collection/mutable/ListMap.scala | 83 +++ .../stdlib/collection/mutable/LongMap.scala | 674 ++++++++++++++++++ 3 files changed, 789 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/ImmutableBuilder.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/ListMap.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/LongMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/ImmutableBuilder.scala b/tests/pos-special/stdlib/collection/mutable/ImmutableBuilder.scala new file mode 100644 index 000000000000..1af98162e9f3 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ImmutableBuilder.scala @@ -0,0 +1,32 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable +import language.experimental.captureChecking + + +/** + * Reusable builder for immutable collections + */ +abstract class ImmutableBuilder[-A, C <: IterableOnce[_]](empty: C) + extends ReusableBuilder[A, C] { + + protected var elems: C = empty + + def clear(): Unit = { elems = empty } + + def result(): C = elems + + override def knownSize: Int = elems.knownSize +} diff --git a/tests/pos-special/stdlib/collection/mutable/ListMap.scala b/tests/pos-special/stdlib/collection/mutable/ListMap.scala new file mode 100644 index 000000000000..8ddbc264e47b --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/ListMap.scala @@ -0,0 +1,83 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.annotation.tailrec +import scala.collection.generic.DefaultSerializable +import scala.collection.immutable.List +import language.experimental.captureChecking + +/** A simple mutable map backed by a list, so it preserves insertion order. + * + * @tparam K the type of the keys contained in this list map. + * @tparam V the type of the values assigned to keys in this list map. + * + * @define Coll `mutable.ListMap` + * @define coll mutable list map + * @define mayNotTerminateInf + * @define willNotTerminateInf + * @define orderDependent + * @define orderDependentFold + */ +@deprecated("Use an immutable.ListMap assigned to a var instead of mutable.ListMap", "2.13.0") +class ListMap[sealed K, sealed V] + extends AbstractMap[K, V] + with MapOps[K, V, ListMap, ListMap[K, V]] + with StrictOptimizedIterableOps[(K, V), Iterable, ListMap[K, V]] + with StrictOptimizedMapOps[K, V, ListMap, ListMap[K, V]] + with MapFactoryDefaults[K, V, ListMap, Iterable] + with DefaultSerializable { + + override def mapFactory: MapFactory[ListMap] = ListMap + + private[this] var elems: List[(K, V)] = List() + private[this] var siz: Int = 0 + + def get(key: K): Option[V] = elems find (_._1 == key) map (_._2) + def iterator: Iterator[(K, V)] = elems.iterator + + final override def addOne(kv: (K, V)) = { + val (e, key0) = remove(kv._1, elems, List()) + elems = (key0, kv._2) :: e + siz += 1; this + } + + final override def subtractOne(key: K) = { elems = remove(key, elems, List())._1; this } + + @tailrec + private def remove(key: K, elems: List[(K, V)], acc: List[(K, V)]): (List[(K, V)], K) = { + if (elems.isEmpty) (acc, key) + else if (elems.head._1 == key) { siz -= 1; (acc ::: elems.tail, elems.head._1) } + else remove(key, elems.tail, elems.head :: acc) + } + + final override def clear(): Unit = { elems = List(); siz = 0 } + + final override def size: Int = siz + override def knownSize: Int = size + override def isEmpty: Boolean = size == 0 + override protected[this] def stringPrefix = "ListMap" +} + +/** $factoryInfo + * @define Coll `mutable.ListMap` + * @define coll mutable list map + */ +@SerialVersionUID(3L) +@deprecated("Use an immutable.ListMap assigned to a var instead of mutable.ListMap", "2.13.0") +object ListMap extends MapFactory[ListMap] { + def empty[sealed K, sealed V]: ListMap[K, V] = new ListMap[K, V] + def from[sealed K, sealed V](it: IterableOnce[(K, V)]^): ListMap[K,V] = Growable.from(empty[K, V], it) + def newBuilder[sealed K, sealed V]: Builder[(K, V), ListMap[K,V]] = new GrowableBuilder(empty[K, V]) +} diff --git a/tests/pos-special/stdlib/collection/mutable/LongMap.scala b/tests/pos-special/stdlib/collection/mutable/LongMap.scala new file mode 100644 index 000000000000..2c757160ec77 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/LongMap.scala @@ -0,0 +1,674 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.collection.generic.DefaultSerializationProxy +import scala.language.implicitConversions +import language.experimental.captureChecking + +/** This class implements mutable maps with `Long` keys based on a hash table with open addressing. + * + * Basic map operations on single entries, including `contains` and `get`, + * are typically substantially faster with `LongMap` than [[HashMap]]. Methods + * that act on the whole map, including `foreach` and `map` are not in + * general expected to be faster than with a generic map, save for those + * that take particular advantage of the internal structure of the map: + * `foreachKey`, `foreachValue`, `mapValuesNow`, and `transformValues`. + * + * Maps with open addressing may become less efficient at lookup after + * repeated addition/removal of elements. Although `LongMap` makes a + * decent attempt to remain efficient regardless, calling `repack` + * on a map that will no longer have elements removed but will be + * used heavily may save both time and storage space. + * + * This map is not intended to contain more than 2^29 entries (approximately + * 500 million). The maximum capacity is 2^30, but performance will degrade + * rapidly as 2^30 is approached. + * + */ +final class LongMap[sealed V] private[collection] (defaultEntry: Long -> V, initialBufferSize: Int, initBlank: Boolean) + extends AbstractMap[Long, V] + with MapOps[Long, V, Map, LongMap[V]] + with StrictOptimizedIterableOps[(Long, V), Iterable, LongMap[V]] + with Serializable { + import LongMap._ + + def this() = this(LongMap.exceptionDefault, 16, true) + + // TODO: override clear() with an optimization more tailored for efficiency. + override protected def fromSpecific(coll: scala.collection.IterableOnce[(Long, V)]^): LongMap[V] = { + //TODO should this be the default implementation of this method in StrictOptimizedIterableOps? + val b = newSpecificBuilder + b.sizeHint(coll) + b.addAll(coll) + b.result() + } + override protected def newSpecificBuilder: Builder[(Long, V),LongMap[V]] = new GrowableBuilder(LongMap.empty[V]) + + /** Creates a new `LongMap` that returns default values according to a supplied key-value mapping. */ + def this(defaultEntry: Long -> V) = this(defaultEntry, 16, true) + + /** Creates a new `LongMap` with an initial buffer of specified size. + * + * A LongMap can typically contain half as many elements as its buffer size + * before it requires resizing. + */ + def this(initialBufferSize: Int) = this(LongMap.exceptionDefault, initialBufferSize, true) + + /** Creates a new `LongMap` with specified default values and initial buffer size. */ + def this(defaultEntry: Long -> V, initialBufferSize: Int) = this(defaultEntry, initialBufferSize, true) + + private[this] var mask = 0 + private[this] var extraKeys: Int = 0 + private[this] var zeroValue: AnyRef = null + private[this] var minValue: AnyRef = null + private[this] var _size = 0 + private[this] var _vacant = 0 + private[this] var _keys: Array[Long] = null + private[this] var _values: Array[AnyRef] = null + + if (initBlank) defaultInitialize(initialBufferSize) + + private[this] def defaultInitialize(n: Int) = { + mask = + if (n<0) 0x7 + else (((1 << (32 - java.lang.Integer.numberOfLeadingZeros(n-1))) - 1) & 0x3FFFFFFF) | 0x7 + _keys = new Array[Long](mask+1) + _values = new Array[AnyRef](mask+1) + } + + private[collection] def initializeTo( + m: Int, ek: Int, zv: AnyRef, mv: AnyRef, sz: Int, vc: Int, kz: Array[Long], vz: Array[AnyRef] + ): Unit = { + mask = m; extraKeys = ek; zeroValue = zv; minValue = mv; _size = sz; _vacant = vc; _keys = kz; _values = vz + } + + override def size: Int = _size + (extraKeys+1)/2 + override def knownSize: Int = size + override def isEmpty: Boolean = size == 0 + override def empty: LongMap[V] = new LongMap() + + private def imbalanced: Boolean = + (_size + _vacant) > 0.5*mask || _vacant > _size + + private def toIndex(k: Long): Int = { + // Part of the MurmurHash3 32 bit finalizer + val h = ((k ^ (k >>> 32)) & 0xFFFFFFFFL).toInt + val x = (h ^ (h >>> 16)) * 0x85EBCA6B + (x ^ (x >>> 13)) & mask + } + + private def seekEmpty(k: Long): Int = { + var e = toIndex(k) + var x = 0 + while (_keys(e) != 0) { x += 1; e = (e + 2*(x+1)*x - 3) & mask } + e + } + + private def seekEntry(k: Long): Int = { + var e = toIndex(k) + var x = 0 + var q = 0L + while ({ q = _keys(e); if (q==k) return e; q != 0}) { x += 1; e = (e + 2*(x+1)*x - 3) & mask } + e | MissingBit + } + + private def seekEntryOrOpen(k: Long): Int = { + var e = toIndex(k) + var x = 0 + var q = 0L + while ({ q = _keys(e); if (q==k) return e; q+q != 0}) { + x += 1 + e = (e + 2*(x+1)*x - 3) & mask + } + if (q == 0) return e | MissingBit + val o = e | MissVacant + while ({ q = _keys(e); if (q==k) return e; q != 0}) { + x += 1 + e = (e + 2*(x+1)*x - 3) & mask + } + o + } + + override def contains(key: Long): Boolean = { + if (key == -key) (((key>>>63).toInt+1) & extraKeys) != 0 + else seekEntry(key) >= 0 + } + + override def get(key: Long): Option[V] = { + if (key == -key) { + if ((((key>>>63).toInt+1) & extraKeys) == 0) None + else if (key == 0) Some(zeroValue.asInstanceOf[V]) + else Some(minValue.asInstanceOf[V]) + } + else { + val i = seekEntry(key) + if (i < 0) None else Some(_values(i).asInstanceOf[V]) + } + } + + override def getOrElse[V1 >: V](key: Long, default: => V1): V1 = { + if (key == -key) { + if ((((key>>>63).toInt+1) & extraKeys) == 0) default + else if (key == 0) zeroValue.asInstanceOf[V1] + else minValue.asInstanceOf[V1] + } + else { + val i = seekEntry(key) + if (i < 0) default else _values(i).asInstanceOf[V1] + } + } + + override def getOrElseUpdate(key: Long, defaultValue: => V): V = { + if (key == -key) { + val kbits = (key>>>63).toInt + 1 + if ((kbits & extraKeys) == 0) { + val value = defaultValue + extraKeys |= kbits + if (key == 0) zeroValue = value.asInstanceOf[AnyRef] + else minValue = value.asInstanceOf[AnyRef] + value + } + else if (key == 0) zeroValue.asInstanceOf[V] + else minValue.asInstanceOf[V] + } + else { + var i = seekEntryOrOpen(key) + if (i < 0) { + // It is possible that the default value computation was side-effecting + // Our hash table may have resized or even contain what we want now + // (but if it does, we'll replace it) + val value = { + val ok = _keys + val ans = defaultValue + if (ok ne _keys) { + i = seekEntryOrOpen(key) + if (i >= 0) _size -= 1 + } + ans + } + _size += 1 + val j = i & IndexMask + _keys(j) = key + _values(j) = value.asInstanceOf[AnyRef] + if ((i & VacantBit) != 0) _vacant -= 1 + else if (imbalanced) repack() + value + } + else _values(i).asInstanceOf[V] + } + } + + /** Retrieves the value associated with a key, or the default for that type if none exists + * (null for AnyRef, 0 for floats and integers). + * + * Note: this is the fastest way to retrieve a value that may or + * may not exist, if the default null/zero is acceptable. For key/value + * pairs that do exist, `apply` (i.e. `map(key)`) is equally fast. + */ + def getOrNull(key: Long): V = { + if (key == -key) { + if ((((key>>>63).toInt+1) & extraKeys) == 0) null.asInstanceOf[V] + else if (key == 0) zeroValue.asInstanceOf[V] + else minValue.asInstanceOf[V] + } + else { + val i = seekEntry(key) + if (i < 0) null.asInstanceOf[V] else _values(i).asInstanceOf[V] + } + } + + /** Retrieves the value associated with a key. + * If the key does not exist in the map, the `defaultEntry` for that key + * will be returned instead. + */ + override def apply(key: Long): V = { + if (key == -key) { + if ((((key>>>63).toInt+1) & extraKeys) == 0) defaultEntry(key) + else if (key == 0) zeroValue.asInstanceOf[V] + else minValue.asInstanceOf[V] + } + else { + val i = seekEntry(key) + if (i < 0) defaultEntry(key) else _values(i).asInstanceOf[V] + } + } + + /** The user-supplied default value for the key. Throws an exception + * if no other default behavior was specified. + */ + override def default(key: Long) = defaultEntry(key) + + private def repack(newMask: Int): Unit = { + val ok = _keys + val ov = _values + mask = newMask + _keys = new Array[Long](mask+1) + _values = new Array[AnyRef](mask+1) + _vacant = 0 + var i = 0 + while (i < ok.length) { + val k = ok(i) + if (k != -k) { + val j = seekEmpty(k) + _keys(j) = k + _values(j) = ov(i) + } + i += 1 + } + } + + /** Repacks the contents of this `LongMap` for maximum efficiency of lookup. + * + * For maps that undergo a complex creation process with both addition and + * removal of keys, and then are used heavily with no further removal of + * elements, calling `repack` after the end of the creation can result in + * improved performance. Repacking takes time proportional to the number + * of entries in the map. + */ + def repack(): Unit = { + var m = mask + if (_size + _vacant >= 0.5*mask && !(_vacant > 0.2*mask)) m = ((m << 1) + 1) & IndexMask + while (m > 8 && 8*_size < m) m = m >>> 1 + repack(m) + } + + override def put(key: Long, value: V): Option[V] = { + if (key == -key) { + if (key == 0) { + val ans = if ((extraKeys&1) == 1) Some(zeroValue.asInstanceOf[V]) else None + zeroValue = value.asInstanceOf[AnyRef] + extraKeys |= 1 + ans + } + else { + val ans = if ((extraKeys&2) == 1) Some(minValue.asInstanceOf[V]) else None + minValue = value.asInstanceOf[AnyRef] + extraKeys |= 2 + ans + } + } + else { + val i = seekEntryOrOpen(key) + if (i < 0) { + val j = i & IndexMask + _keys(j) = key + _values(j) = value.asInstanceOf[AnyRef] + _size += 1 + if ((i & VacantBit) != 0) _vacant -= 1 + else if (imbalanced) repack() + None + } + else { + val ans = Some(_values(i).asInstanceOf[V]) + _keys(i) = key + _values(i) = value.asInstanceOf[AnyRef] + ans + } + } + } + + /** Updates the map to include a new key-value pair. + * + * This is the fastest way to add an entry to a `LongMap`. + */ + override def update(key: Long, value: V): Unit = { + if (key == -key) { + if (key == 0) { + zeroValue = value.asInstanceOf[AnyRef] + extraKeys |= 1 + } + else { + minValue = value.asInstanceOf[AnyRef] + extraKeys |= 2 + } + } + else { + val i = seekEntryOrOpen(key) + if (i < 0) { + val j = i & IndexMask + _keys(j) = key + _values(j) = value.asInstanceOf[AnyRef] + _size += 1 + if ((i & VacantBit) != 0) _vacant -= 1 + else if (imbalanced) repack() + } + else { + _keys(i) = key + _values(i) = value.asInstanceOf[AnyRef] + } + } + } + + /** Adds a new key/value pair to this map and returns the map. */ + @deprecated("Use `addOne` or `update` instead; infix operations with an operand of multiple args will be deprecated", "2.13.3") + def +=(key: Long, value: V): this.type = { update(key, value); this } + + /** Adds a new key/value pair to this map and returns the map. */ + @inline final def addOne(key: Long, value: V): this.type = { update(key, value); this } + + @inline override final def addOne(kv: (Long, V)): this.type = { update(kv._1, kv._2); this } + + def subtractOne(key: Long): this.type = { + if (key == -key) { + if (key == 0L) { + extraKeys &= 0x2 + zeroValue = null + } + else { + extraKeys &= 0x1 + minValue = null + } + } + else { + val i = seekEntry(key) + if (i >= 0) { + _size -= 1 + _vacant += 1 + _keys(i) = Long.MinValue + _values(i) = null + } + } + this + } + + def iterator: Iterator[(Long, V)] = new AbstractIterator[(Long, V)] { + private[this] val kz = _keys + private[this] val vz = _values + + private[this] var nextPair: (Long, V) = + if (extraKeys==0) null + else if ((extraKeys&1)==1) (0L, zeroValue.asInstanceOf[V]) + else (Long.MinValue, minValue.asInstanceOf[V]) + + private[this] var anotherPair: (Long, V) = + if (extraKeys==3) (Long.MinValue, minValue.asInstanceOf[V]) + else null + + private[this] var index = 0 + + def hasNext: Boolean = nextPair != null || (index < kz.length && { + var q = kz(index) + while (q == -q) { + index += 1 + if (index >= kz.length) return false + q = kz(index) + } + nextPair = (kz(index), vz(index).asInstanceOf[V]) + index += 1 + true + }) + def next() = { + if (nextPair == null && !hasNext) throw new NoSuchElementException("next") + val ans = nextPair + if (anotherPair != null) { + nextPair = anotherPair + anotherPair = null + } + else nextPair = null + ans + } + } + + // TODO PERF override these for efficiency. See immutable.LongMap for how to organize the code. + override def keysIterator: Iterator[Long] = super.keysIterator + override def valuesIterator: Iterator[V] = super.valuesIterator + + override def foreach[U](f: ((Long,V)) => U): Unit = { + if ((extraKeys & 1) == 1) f((0L, zeroValue.asInstanceOf[V])) + if ((extraKeys & 2) == 2) f((Long.MinValue, minValue.asInstanceOf[V])) + var i,j = 0 + while (i < _keys.length & j < _size) { + val k = _keys(i) + if (k != -k) { + j += 1 + f((k, _values(i).asInstanceOf[V])) + } + i += 1 + } + } + + override def foreachEntry[U](f: (Long,V) => U): Unit = { + if ((extraKeys & 1) == 1) f(0L, zeroValue.asInstanceOf[V]) + if ((extraKeys & 2) == 2) f(Long.MinValue, minValue.asInstanceOf[V]) + var i,j = 0 + while (i < _keys.length & j < _size) { + val k = _keys(i) + if (k != -k) { + j += 1 + f(k, _values(i).asInstanceOf[V]) + } + i += 1 + } + } + + override def clone(): LongMap[V] = { + val kz = java.util.Arrays.copyOf(_keys, _keys.length) + val vz = java.util.Arrays.copyOf(_values, _values.length) + val lm = new LongMap[V](defaultEntry, 1, false) + lm.initializeTo(mask, extraKeys, zeroValue, minValue, _size, _vacant, kz, vz) + lm + } + + @deprecated("Consider requiring an immutable Map or fall back to Map.concat", "2.13.0") + override def +[V1 >: V](kv: (Long, V1)): LongMap[V1] = { + val lm = clone().asInstanceOf[LongMap[V1]] + lm += kv + lm + } + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + override def + [sealed V1 >: V](elem1: (Long, V1), elem2: (Long, V1), elems: (Long, V1)*): LongMap[V1] = { + val m = this + elem1 + elem2 + if(elems.isEmpty) m else m.concat(elems) + } + + override def concat[sealed V1 >: V](xs: scala.collection.IterableOnce[(Long, V1)]^): LongMap[V1] = { + val lm = clone().asInstanceOf[LongMap[V1]] + xs.iterator.foreach(kv => lm += kv) + lm + } + + override def ++ [sealed V1 >: V](xs: scala.collection.IterableOnce[(Long, V1)]^): LongMap[V1] = concat(xs) + + @deprecated("Use m.clone().addOne(k,v) instead of m.updated(k, v)", "2.13.0") + override def updated[V1 >: V](key: Long, value: V1): LongMap[V1] = + clone().asInstanceOf[LongMap[V1]].addOne(key, value) + + /** Applies a function to all keys of this map. */ + def foreachKey[A](f: Long => A): Unit = { + if ((extraKeys & 1) == 1) f(0L) + if ((extraKeys & 2) == 2) f(Long.MinValue) + var i,j = 0 + while (i < _keys.length & j < _size) { + val k = _keys(i) + if (k != -k) { + j += 1 + f(k) + } + i += 1 + } + } + + /** Applies a function to all values of this map. */ + def foreachValue[A](f: V => A): Unit = { + if ((extraKeys & 1) == 1) f(zeroValue.asInstanceOf[V]) + if ((extraKeys & 2) == 2) f(minValue.asInstanceOf[V]) + var i,j = 0 + while (i < _keys.length & j < _size) { + val k = _keys(i) + if (k != -k) { + j += 1 + f(_values(i).asInstanceOf[V]) + } + i += 1 + } + } + + /** Creates a new `LongMap` with different values. + * Unlike `mapValues`, this method generates a new + * collection immediately. + */ + def mapValuesNow[sealed V1](f: V => V1): LongMap[V1] = { + val zv = if ((extraKeys & 1) == 1) f(zeroValue.asInstanceOf[V]).asInstanceOf[AnyRef] else null + val mv = if ((extraKeys & 2) == 2) f(minValue.asInstanceOf[V]).asInstanceOf[AnyRef] else null + val lm = new LongMap[V1](LongMap.exceptionDefault, 1, false) + val kz = java.util.Arrays.copyOf(_keys, _keys.length) + val vz = new Array[AnyRef](_values.length) + var i,j = 0 + while (i < _keys.length & j < _size) { + val k = _keys(i) + if (k != -k) { + j += 1 + vz(i) = f(_values(i).asInstanceOf[V]).asInstanceOf[AnyRef] + } + i += 1 + } + lm.initializeTo(mask, extraKeys, zv, mv, _size, _vacant, kz, vz) + lm + } + + /** Applies a transformation function to all values stored in this map. + * Note: the default, if any, is not transformed. + */ + @deprecated("Use transformValuesInPlace instead of transformValues", "2.13.0") + @`inline` final def transformValues(f: V => V): this.type = transformValuesInPlace(f) + + /** Applies a transformation function to all values stored in this map. + * Note: the default, if any, is not transformed. + */ + def transformValuesInPlace(f: V => V): this.type = { + if ((extraKeys & 1) == 1) zeroValue = f(zeroValue.asInstanceOf[V]).asInstanceOf[AnyRef] + if ((extraKeys & 2) == 2) minValue = f(minValue.asInstanceOf[V]).asInstanceOf[AnyRef] + var i,j = 0 + while (i < _keys.length & j < _size) { + val k = _keys(i) + if (k != -k) { + j += 1 + _values(i) = f(_values(i).asInstanceOf[V]).asInstanceOf[AnyRef] + } + i += 1 + } + this + } + + def map[sealed V2](f: ((Long, V)) => (Long, V2)): LongMap[V2] = LongMap.from(new View.Map(coll, f)) + + def flatMap[sealed V2](f: ((Long, V)) => IterableOnce[(Long, V2)]): LongMap[V2] = LongMap.from(new View.FlatMap(coll, f)) + + def collect[sealed V2](pf: PartialFunction[(Long, V), (Long, V2)]): LongMap[V2] = + strictOptimizedCollect(LongMap.newBuilder[V2], pf) + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(LongMap.toFactory[V](LongMap), this) + + override protected[this] def className = "LongMap" +} + +object LongMap { + private final val IndexMask = 0x3FFFFFFF + private final val MissingBit = 0x80000000 + private final val VacantBit = 0x40000000 + private final val MissVacant = 0xC0000000 + + private val exceptionDefault: Long -> Nothing = (k: Long) => throw new NoSuchElementException(k.toString) + + /** A builder for instances of `LongMap`. + * + * This builder can be reused to create multiple instances. + */ + final class LongMapBuilder[sealed V] extends ReusableBuilder[(Long, V), LongMap[V]] { + private[collection] var elems: LongMap[V] = new LongMap[V] + override def addOne(entry: (Long, V)): this.type = { + elems += entry + this + } + def clear(): Unit = elems = new LongMap[V] + def result(): LongMap[V] = elems + override def knownSize: Int = elems.knownSize + } + + /** Creates a new `LongMap` with zero or more key/value pairs. */ + def apply[sealed V](elems: (Long, V)*): LongMap[V] = buildFromIterableOnce(elems) + + private def buildFromIterableOnce[sealed V](elems: IterableOnce[(Long, V)]^): LongMap[V] = { + var sz = elems.knownSize + if(sz < 0) sz = 4 + val lm = new LongMap[V](sz * 2) + elems.iterator.foreach{ case (k,v) => lm(k) = v } + if (lm.size < (sz>>3)) lm.repack() + lm + } + + /** Creates a new empty `LongMap`. */ + def empty[sealed V]: LongMap[V] = new LongMap[V] + + /** Creates a new empty `LongMap` with the supplied default */ + def withDefault[sealed V](default: Long -> V): LongMap[V] = new LongMap[V](default) + + /** Creates a new `LongMap` from an existing source collection. A source collection + * which is already a `LongMap` gets cloned. + * + * @param source Source collection + * @tparam A the type of the collection’s elements + * @return a new `LongMap` with the elements of `source` + */ + def from[sealed V](source: IterableOnce[(Long, V)]^): LongMap[V] = source match { + case source: LongMap[_] => source.clone().asInstanceOf[LongMap[V]] + case _ => buildFromIterableOnce(source) + } + + def newBuilder[sealed V]: ReusableBuilder[(Long, V), LongMap[V]] = new LongMapBuilder[V] + + /** Creates a new `LongMap` from arrays of keys and values. + * Equivalent to but more efficient than `LongMap((keys zip values): _*)`. + */ + def fromZip[sealed V](keys: Array[Long], values: Array[V]): LongMap[V] = { + val sz = math.min(keys.length, values.length) + val lm = new LongMap[V](sz * 2) + var i = 0 + while (i < sz) { lm(keys(i)) = values(i); i += 1 } + if (lm.size < (sz>>3)) lm.repack() + lm + } + + /** Creates a new `LongMap` from keys and values. + * Equivalent to but more efficient than `LongMap((keys zip values): _*)`. + */ + def fromZip[sealed V](keys: scala.collection.Iterable[Long], values: scala.collection.Iterable[V]): LongMap[V] = { + val sz = math.min(keys.size, values.size) + val lm = new LongMap[V](sz * 2) + val ki = keys.iterator + val vi = values.iterator + while (ki.hasNext && vi.hasNext) lm(ki.next()) = vi.next() + if (lm.size < (sz >> 3)) lm.repack() + lm + } + + implicit def toFactory[sealed V](dummy: LongMap.type): Factory[(Long, V), LongMap[V]] = ToFactory.asInstanceOf[Factory[(Long, V), LongMap[V]]] + + @SerialVersionUID(3L) + private[this] object ToFactory extends Factory[(Long, AnyRef), LongMap[AnyRef]] with Serializable { + def fromSpecific(it: IterableOnce[(Long, AnyRef)]^): LongMap[AnyRef] = LongMap.from[AnyRef](it) + def newBuilder: Builder[(Long, AnyRef), LongMap[AnyRef]] = LongMap.newBuilder[AnyRef] + } + + implicit def toBuildFrom[V](factory: LongMap.type): BuildFrom[Any, (Long, V), LongMap[V]] = ToBuildFrom.asInstanceOf[BuildFrom[Any, (Long, V), LongMap[V]]] + private object ToBuildFrom extends BuildFrom[Any, (Long, AnyRef), LongMap[AnyRef]] { + def fromSpecific(from: Any)(it: IterableOnce[(Long, AnyRef)]^) = LongMap.from(it) + def newBuilder(from: Any) = LongMap.newBuilder[AnyRef] + } + + implicit def iterableFactory[sealed V]: Factory[(Long, V), LongMap[V]] = toFactory(this) + implicit def buildFromLongMap[V]: BuildFrom[LongMap[_], (Long, V), LongMap[V]] = toBuildFrom(this) +} From ae605d671dc659762e84d98417dc8f46275759fa Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 16:34:55 +0100 Subject: [PATCH 48/89] Add WeakHashMap and MultiMap to stdlib --- .../stdlib/collection/mutable/MultiMap.scala | 116 ++++++++++++++++++ .../collection/mutable/WeakHashMap.scala | 56 +++++++++ 2 files changed, 172 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/MultiMap.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/WeakHashMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/MultiMap.scala b/tests/pos-special/stdlib/collection/mutable/MultiMap.scala new file mode 100644 index 000000000000..0b250a5548ef --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/MultiMap.scala @@ -0,0 +1,116 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.mutable + +import language.experimental.captureChecking + +/** A trait for mutable maps with multiple values assigned to a key. + * + * This class is typically used as a mixin. It turns maps which map `K` + * to `Set[V]` objects into multimaps that map `K` to `V` objects. + * + * @example {{{ + * // first import all necessary types from package `collection.mutable` + * import collection.mutable.{ HashMap, MultiMap, Set } + * + * // to create a `MultiMap` the easiest way is to mixin it into a normal + * // `Map` instance + * val mm = new HashMap[Int, Set[String]] with MultiMap[Int, String] + * + * // to add key-value pairs to a multimap it is important to use + * // the method `addBinding` because standard methods like `+` will + * // overwrite the complete key-value pair instead of adding the + * // value to the existing key + * mm.addBinding(1, "a") + * mm.addBinding(2, "b") + * mm.addBinding(1, "c") + * + * // mm now contains `Map(2 -> Set(b), 1 -> Set(c, a))` + * + * // to check if the multimap contains a value there is method + * // `entryExists`, which allows to traverse the including set + * mm.entryExists(1, _ == "a") == true + * mm.entryExists(1, _ == "b") == false + * mm.entryExists(2, _ == "b") == true + * + * // to remove a previous added value there is the method `removeBinding` + * mm.removeBinding(1, "a") + * mm.entryExists(1, _ == "a") == false + * }}} + * + * @define coll multimap + * @define Coll `MultiMap` + */ +@deprecated("Use a scala.collection.mutable.MultiDict in the scala-collection-contrib module", "2.13.0") +trait MultiMap[K, V] extends Map[K, Set[V]] { + /** Creates a new set. + * + * Classes that use this trait as a mixin can override this method + * to have the desired implementation of sets assigned to new keys. + * By default this is `HashSet`. + * + * @return An empty set of values of type `V`. + */ + protected def makeSet: Set[V] = new HashSet[V] + + /** Assigns the specified `value` to a specified `key`. If the key + * already has a binding to equal to `value`, nothing is changed; + * otherwise a new binding is added for that `key`. + * + * @param key The key to which to bind the new value. + * @param value The value to bind to the key. + * @return A reference to this multimap. + */ + def addBinding(key: K, value: V): this.type = { + get(key) match { + case None => + val set = makeSet + set += value + this(key) = set + case Some(set) => + set += value + } + this + } + + /** Removes the binding of `value` to `key` if it exists, otherwise this + * operation doesn't have any effect. + * + * If this was the last value assigned to the specified key, the + * set assigned to that key will be removed as well. + * + * @param key The key of the binding. + * @param value The value to remove. + * @return A reference to this multimap. + */ + def removeBinding(key: K, value: V): this.type = { + get(key) match { + case None => + case Some(set) => + set -= value + if (set.isEmpty) this -= key + } + this + } + + /** Checks if there exists a binding to `key` such that it satisfies the predicate `p`. + * + * @param key The key for which the predicate is checked. + * @param p The predicate which a value assigned to the key must satisfy. + * @return A boolean if such a binding exists + */ + def entryExists(key: K, p: V => Boolean): Boolean = get(key) match { + case None => false + case Some(set) => set exists p + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/WeakHashMap.scala b/tests/pos-special/stdlib/collection/mutable/WeakHashMap.scala new file mode 100644 index 000000000000..a9498b7fc69b --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/WeakHashMap.scala @@ -0,0 +1,56 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.annotation.nowarn +import scala.collection.convert.JavaCollectionWrappers.{JMapWrapper, JMapWrapperLike} +import language.experimental.captureChecking + +/** A hash map with references to entries which are weakly reachable. Entries are + * removed from this map when the key is no longer (strongly) referenced. This class wraps + * `java.util.WeakHashMap`. + * + * @tparam K type of keys contained in this map + * @tparam V type of values associated with the keys + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#weak-hash-maps "Scala's Collection Library overview"]] + * section on `Weak Hash Maps` for more information. + * + * @define Coll `WeakHashMap` + * @define coll weak hash map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@SerialVersionUID(3L) +class WeakHashMap[sealed K, sealed V] extends JMapWrapper[K, V](new java.util.WeakHashMap) + with JMapWrapperLike[K, V, WeakHashMap, WeakHashMap[K, V]] + with MapFactoryDefaults[K, V, WeakHashMap, Iterable] { + override def empty = new WeakHashMap[K, V] + override def mapFactory: MapFactory[WeakHashMap] = WeakHashMap + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "WeakHashMap" +} + +/** $factoryInfo + * @define Coll `WeakHashMap` + * @define coll weak hash map + */ +@SerialVersionUID(3L) +object WeakHashMap extends MapFactory[WeakHashMap] { + def empty[sealed K, sealed V]: WeakHashMap[K,V] = new WeakHashMap[K, V] + def from[sealed K, sealed V](it: collection.IterableOnce[(K, V)]^): WeakHashMap[K,V] = Growable.from(empty[K, V], it) + def newBuilder[sealed K, sealed V]: Builder[(K, V), WeakHashMap[K,V]] = new GrowableBuilder(WeakHashMap.empty[K, V]) +} + From b0d3bbc8e1c9e512dbc4fe1a489fd3333fff16e2 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 16:40:26 +0100 Subject: [PATCH 49/89] Add UnrolledBuffer to stdlib --- .../collection/mutable/UnrolledBuffer.scala | 443 ++++++++++++++++++ .../stdlib/collection/mutable/package.scala | 42 ++ 2 files changed, 485 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/UnrolledBuffer.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/package.scala diff --git a/tests/pos-special/stdlib/collection/mutable/UnrolledBuffer.scala b/tests/pos-special/stdlib/collection/mutable/UnrolledBuffer.scala new file mode 100644 index 000000000000..2015b76a31b8 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/UnrolledBuffer.scala @@ -0,0 +1,443 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.annotation.tailrec +import scala.collection.generic.DefaultSerializable +import scala.reflect.ClassTag +import scala.collection.immutable.Nil +import language.experimental.captureChecking + +/** A buffer that stores elements in an unrolled linked list. + * + * Unrolled linked lists store elements in linked fixed size + * arrays. + * + * Unrolled buffers retain locality and low memory overhead + * properties of array buffers, but offer much more efficient + * element addition, since they never reallocate and copy the + * internal array. + * + * However, they provide `O(n/m)` complexity random access, + * where `n` is the number of elements, and `m` the size of + * internal array chunks. + * + * Ideal to use when: + * - elements are added to the buffer and then all of the + * elements are traversed sequentially + * - two unrolled buffers need to be concatenated (see `concat`) + * + * Better than singly linked lists for random access, but + * should still be avoided for such a purpose. + * + * @define coll unrolled buffer + * @define Coll `UnrolledBuffer` + * + */ +@SerialVersionUID(3L) +sealed class UnrolledBuffer[sealed T](implicit val tag: ClassTag[T]) + extends AbstractBuffer[T] + with Buffer[T] + with Seq[T] + with SeqOps[T, UnrolledBuffer, UnrolledBuffer[T]] + with StrictOptimizedSeqOps[T, UnrolledBuffer, UnrolledBuffer[T]] + with EvidenceIterableFactoryDefaults[T, UnrolledBuffer, ClassTag] + with Builder[T, UnrolledBuffer[T]] + with DefaultSerializable { + + import UnrolledBuffer.Unrolled + + @transient private var headptr = newUnrolled + @transient private var lastptr = headptr + @transient private var sz = 0 + + private[collection] def headPtr = headptr + private[collection] def headPtr_=(head: Unrolled[T]) = headptr = head + private[collection] def lastPtr = lastptr + private[collection] def lastPtr_=(last: Unrolled[T]) = lastptr = last + private[collection] def size_=(s: Int) = sz = s + + protected def evidenceIterableFactory: UnrolledBuffer.type = UnrolledBuffer + protected def iterableEvidence: ClassTag[T] = tag + + override def iterableFactory: SeqFactory[UnrolledBuffer] = UnrolledBuffer.untagged + + protected def newUnrolled = new Unrolled[T](this) + + // The below would allow more flexible behavior without requiring inheritance + // that is risky because all the important internals are private. + // private var myLengthPolicy: Int => Int = x => x + // + // /** Specifies how the array lengths should vary. + // * + // * By default, `UnrolledBuffer` uses arrays of a fixed size. A length + // * policy can be given that changes this scheme to, for instance, an + // * exponential growth. + // * + // * @param nextLength computes the length of the next array from the length of the latest one + // */ + // def setLengthPolicy(nextLength: Int => Int): Unit = { myLengthPolicy = nextLength } + private[collection] def calcNextLength(sz: Int) = sz // myLengthPolicy(sz) + + def classTagCompanion = UnrolledBuffer + + /** Concatenates the target unrolled buffer to this unrolled buffer. + * + * The specified buffer `that` is cleared after this operation. This is + * an O(1) operation. + * + * @param that the unrolled buffer whose elements are added to this buffer + */ + def concat(that: UnrolledBuffer[T]) = { + // bind the two together + if (!lastptr.bind(that.headptr)) lastptr = that.lastPtr + + // update size + sz += that.sz + + // `that` is no longer usable, so clear it + // here we rely on the fact that `clear` allocates + // new nodes instead of modifying the previous ones + that.clear() + + // return a reference to this + this + } + + def addOne(elem: T) = { + lastptr = lastptr.append(elem) + sz += 1 + this + } + + def clear(): Unit = { + headptr = newUnrolled + lastptr = headptr + sz = 0 + } + + def iterator: Iterator[T] = new AbstractIterator[T] { + var pos: Int = -1 + var node: Unrolled[T] = headptr + scan() + + private def scan(): Unit = { + pos += 1 + while (pos >= node.size) { + pos = 0 + node = node.next + if (node eq null) return + } + } + def hasNext = node ne null + def next() = if (hasNext) { + val r = node.array(pos) + scan() + r + } else Iterator.empty.next() + } + + // this should be faster than the iterator + override def foreach[U](f: T => U) = headptr.foreach(f) + + def result() = this + + def length = sz + + override def knownSize: Int = sz + + def apply(idx: Int) = + if (idx >= 0 && idx < sz) headptr(idx) + else throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${sz-1})") + + def update(idx: Int, newelem: T) = + if (idx >= 0 && idx < sz) headptr(idx) = newelem + else throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${sz-1})") + + def mapInPlace(f: T => T): this.type = { + headptr.mapInPlace(f) + this + } + + def remove(idx: Int) = + if (idx >= 0 && idx < sz) { + sz -= 1 + headptr.remove(idx, this) + } else throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${sz-1})") + + @tailrec final def remove(idx: Int, count: Int): Unit = + if (count > 0) { + remove(idx) + remove(idx, count-1) + } + + def prepend(elem: T) = { + headptr = headptr prepend elem + sz += 1 + this + } + + def insert(idx: Int, elem: T): Unit = + insertAll(idx, elem :: Nil) + + def insertAll(idx: Int, elems: IterableOnce[T]^): Unit = + if (idx >= 0 && idx <= sz) { + sz += headptr.insertAll(idx, elems, this) + } else throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${sz-1})") + + override def subtractOne(elem: T): this.type = { + if (headptr.subtractOne(elem, this)) { + sz -= 1 + } + this + } + + def patchInPlace(from: Int, patch: collection.IterableOnce[T]^, replaced: Int): this.type = { + remove(from, replaced) + insertAll(from, patch) + this + } + + private def writeObject(out: java.io.ObjectOutputStream): Unit = { + out.defaultWriteObject + out writeInt sz + for (elem <- this) out writeObject elem + } + + private def readObject(in: java.io.ObjectInputStream): Unit = { + in.defaultReadObject + + val num = in.readInt + + headPtr = newUnrolled + lastPtr = headPtr + sz = 0 + var i = 0 + while (i < num) { + this += in.readObject.asInstanceOf[T] + i += 1 + } + } + + override def clone(): UnrolledBuffer[T] = new UnrolledBuffer[T] ++= this + + override protected[this] def className = "UnrolledBuffer" +} + + +@SerialVersionUID(3L) +object UnrolledBuffer extends StrictOptimizedClassTagSeqFactory[UnrolledBuffer] { self => + + val untagged: SeqFactory[UnrolledBuffer] = new ClassTagSeqFactory.AnySeqDelegate(self) + + def empty[sealed A : ClassTag]: UnrolledBuffer[A] = new UnrolledBuffer[A] + + def from[sealed A : ClassTag](source: scala.collection.IterableOnce[A]^): UnrolledBuffer[A] = newBuilder[A].addAll(source) + + def newBuilder[sealed A : ClassTag]: UnrolledBuffer[A] = new UnrolledBuffer[A] + + final val waterline: Int = 50 + + final def waterlineDenom: Int = 100 + + @deprecated("Use waterlineDenom instead.", "2.13.0") + final val waterlineDelim: Int = waterlineDenom + + private[collection] val unrolledlength = 32 + + /** Unrolled buffer node. + */ + class Unrolled[sealed T: ClassTag] private[collection] (var size: Int, var array: Array[T], var next: Unrolled[T], val buff: UnrolledBuffer[T] = null) { + private[collection] def this() = this(0, new Array[T](unrolledlength), null, null) + private[collection] def this(b: UnrolledBuffer[T]) = this(0, new Array[T](unrolledlength), null, b) + + private def nextlength = if (buff eq null) unrolledlength else buff.calcNextLength(array.length) + + // adds and returns itself or the new unrolled if full + @tailrec final def append(elem: T): Unrolled[T] = if (size < array.length) { + array(size) = elem + size += 1 + this + } else { + next = new Unrolled[T](0, new Array[T](nextlength), null, buff) + next append elem + } + def foreach[U](f: T => U): Unit = { + var unrolled = this + var i = 0 + while (unrolled ne null) { + val chunkarr = unrolled.array + val chunksz = unrolled.size + while (i < chunksz) { + val elem = chunkarr(i) + f(elem) + i += 1 + } + i = 0 + unrolled = unrolled.next + } + } + def mapInPlace(f: T => T): Unit = { + var unrolled = this + var i = 0 + while (unrolled ne null) { + val chunkarr = unrolled.array + val chunksz = unrolled.size + while (i < chunksz) { + val elem = chunkarr(i) + chunkarr(i) = f(elem) + i += 1 + } + i = 0 + unrolled = unrolled.next + } + } + @tailrec final def apply(idx: Int): T = + if (idx < size) array(idx) else next.apply(idx - size) + @tailrec final def update(idx: Int, newelem: T): Unit = + if (idx < size) array(idx) = newelem else next.update(idx - size, newelem) + @tailrec final def locate(idx: Int): Unrolled[T] = + if (idx < size) this else next.locate(idx - size) + def prepend(elem: T) = if (size < array.length) { + // shift the elements of the array right + // then insert the element + shiftright() + array(0) = elem + size += 1 + this + } else { + // allocate a new node and store element + // then make it point to this + val newhead = new Unrolled[T](buff) + newhead append elem + newhead.next = this + newhead + } + // shifts right assuming enough space + private def shiftright(): Unit = { + var i = size - 1 + while (i >= 0) { + array(i + 1) = array(i) + i -= 1 + } + } + // returns pointer to new last if changed + @tailrec final def remove(idx: Int, buffer: UnrolledBuffer[T]): T = + if (idx < size) { + // remove the element + // then try to merge with the next bucket + val r = array(idx) + shiftleft(idx) + size -= 1 + if (tryMergeWithNext()) buffer.lastPtr = this + r + } else next.remove(idx - size, buffer) + + @tailrec final def subtractOne(elem: T, buffer: UnrolledBuffer[T]): Boolean = { + var i = 0 + while (i < size) { + if(array(i) == elem) { + remove(i, buffer) + return true + } + i += 1 + } + if(next ne null) next.subtractOne(elem, buffer) else false + } + + // shifts left elements after `leftb` (overwrites `leftb`) + private def shiftleft(leftb: Int): Unit = { + var i = leftb + while (i < (size - 1)) { + array(i) = array(i + 1) + i += 1 + } + nullout(i, i + 1) + } + protected def tryMergeWithNext() = if (next != null && (size + next.size) < (array.length * waterline / waterlineDenom)) { + // copy the next array, then discard the next node + Array.copy(next.array, 0, array, size, next.size) + size = size + next.size + next = next.next + if (next eq null) true else false // checks if last node was thrown out + } else false + + @tailrec final def insertAll(idx: Int, t: scala.collection.IterableOnce[T]^, buffer: UnrolledBuffer[T]): Int = { + if (idx < size) { + // divide this node at the appropriate position and insert all into head + // update new next + val newnextnode = new Unrolled[T](0, new Array(array.length), null, buff) + Array.copy(array, idx, newnextnode.array, 0, size - idx) + newnextnode.size = size - idx + newnextnode.next = next + + // update this + nullout(idx, size) + size = idx + next = null + + // insert everything from iterable to this + var curr = this + var appended = 0 + for (elem <- t.iterator) { + curr = curr append elem + appended += 1 + } + curr.next = newnextnode + + // try to merge the last node of this with the newnextnode and fix tail pointer if needed + if (curr.tryMergeWithNext()) buffer.lastPtr = curr + else if (newnextnode.next eq null) buffer.lastPtr = newnextnode + appended + } + else if (idx == size || (next eq null)) { + var curr = this + var appended = 0 + for (elem <- t.iterator) { + curr = curr append elem + appended += 1 + } + appended + } + else next.insertAll(idx - size, t, buffer) + } + + private def nullout(from: Int, until: Int): Unit = { + var idx = from + while (idx < until) { + array(idx) = null.asInstanceOf[T] // TODO find a way to assign a default here!! + idx += 1 + } + } + + // assumes this is the last node + // `thathead` and `thatlast` are head and last node + // of the other unrolled list, respectively + def bind(thathead: Unrolled[T]) = { + assert(next eq null) + next = thathead + tryMergeWithNext() + } + + override def toString: String = + array.take(size).mkString("Unrolled@%08x".format(System.identityHashCode(this)) + "[" + size + "/" + array.length + "](", ", ", ")") + " -> " + (if (next ne null) next.toString else "") + } +} + +// This is used by scala.collection.parallel.mutable.UnrolledParArrayCombiner: +// Todo -- revisit whether inheritance is the best way to achieve this functionality +private[collection] class DoublingUnrolledBuffer[sealed T](implicit t: ClassTag[T]) extends UnrolledBuffer[T]()(t) { + override def calcNextLength(sz: Int) = if (sz < 10000) sz * 2 else sz + override protected def newUnrolled = new UnrolledBuffer.Unrolled[T](0, new Array[T](4), null, this) +} diff --git a/tests/pos-special/stdlib/collection/mutable/package.scala b/tests/pos-special/stdlib/collection/mutable/package.scala new file mode 100644 index 000000000000..d658ca5bc65a --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/package.scala @@ -0,0 +1,42 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +import language.experimental.captureChecking + + +package object mutable { + @deprecated("Use ArraySeq instead of WrappedArray; it can represent both, boxed and unboxed arrays", "2.13.0") + type WrappedArray[X] = ArraySeq[X] + @deprecated("Use ArraySeq instead of WrappedArray; it can represent both, boxed and unboxed arrays", "2.13.0") + val WrappedArray = ArraySeq + @deprecated("Use Iterable instead of Traversable", "2.13.0") + type Traversable[X] = Iterable[X] + @deprecated("Use Iterable instead of Traversable", "2.13.0") + val Traversable = Iterable + @deprecated("Use Stack instead of ArrayStack; it now uses an array-based implementation", "2.13.0") + type ArrayStack[X] = Stack[X] + @deprecated("Use Stack instead of ArrayStack; it now uses an array-based implementation", "2.13.0") + val ArrayStack = Stack + + @deprecated("mutable.LinearSeq has been removed; use LinearSeq with mutable.Seq instead", "2.13.0") + type LinearSeq[X] = Seq[X] with scala.collection.LinearSeq[X] + + @deprecated("GrowingBuilder has been renamed to GrowableBuilder", "2.13.0") + type GrowingBuilder[Elem, To <: Growable[Elem]] = GrowableBuilder[Elem, To] + + @deprecated("IndexedOptimizedSeq has been renamed to IndexedSeq", "2.13.0") + type IndexedOptimizedSeq[A] = IndexedSeq[A] + + @deprecated("IndexedOptimizedBuffer has been renamed to IndexedBuffer", "2.13.0") + type IndexedOptimizedBuffer[A] = IndexedBuffer[A] +} From 09e08685b83bbfc2f4e88b1681ee4028c7b93ea2 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 16:50:11 +0100 Subject: [PATCH 50/89] Add mutable TreeMap and RedBlackTree to stdlib --- .../collection/mutable/RedBlackTree.scala | 653 ++++++++++++++++++ .../stdlib/collection/mutable/TreeMap.scala | 258 +++++++ .../stdlib/collection/mutable/TreeSet.scala | 8 +- 3 files changed, 915 insertions(+), 4 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/mutable/RedBlackTree.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/TreeMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/RedBlackTree.scala b/tests/pos-special/stdlib/collection/mutable/RedBlackTree.scala new file mode 100644 index 000000000000..1f320f832cdf --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/RedBlackTree.scala @@ -0,0 +1,653 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.mutable + +import scala.annotation.tailrec +import collection.{AbstractIterator, Iterator} +import java.lang.String +import language.experimental.captureChecking + +/** + * An object containing the red-black tree implementation used by mutable `TreeMaps`. + * + * The trees implemented in this object are *not* thread safe. + */ +private[collection] object RedBlackTree { + + // ---- class structure ---- + + // For performance reasons, this implementation uses `null` references to represent leaves instead of a sentinel node. + // Currently, the internal nodes do not store their subtree size - only the tree object keeps track of their size. + // Therefore, while obtaining the size of the whole tree is O(1), knowing the number of entries inside a range is O(n) + // on the size of the range. + + final class Tree[sealed A, sealed B](var root: Node[A, B], var size: Int) { + def treeCopy(): Tree[A, B] = new Tree(copyTree(root), size) + } + + final class Node[sealed A, sealed B](var key: A, var value: B, var red: Boolean, var left: Node[A, B], var right: Node[A, B], var parent: Node[A, B]) { + override def toString: String = "Node(" + key + ", " + value + ", " + red + ", " + left + ", " + right + ")" + } + + object Tree { + def empty[sealed A, sealed B]: Tree[A, B] = new Tree(null, 0) + } + + object Node { + + @`inline` def apply[sealed A, sealed B](key: A, value: B, red: Boolean, + left: Node[A, B], right: Node[A, B], parent: Node[A, B]): Node[A, B] = + new Node(key, value, red, left, right, parent) + + @`inline` def leaf[sealed A, sealed B](key: A, value: B, red: Boolean, parent: Node[A, B]): Node[A, B] = + new Node(key, value, red, null, null, parent) + + def unapply[A, B](t: Node[A, B]) = Some((t.key, t.value, t.left, t.right, t.parent)) + } + + // ---- getters ---- + + def isRed(node: Node[_, _]) = (node ne null) && node.red + def isBlack(node: Node[_, _]) = (node eq null) || !node.red + + // ---- size ---- + + def size(node: Node[_, _]): Int = if (node eq null) 0 else 1 + size(node.left) + size(node.right) + def size(tree: Tree[_, _]): Int = tree.size + def isEmpty(tree: Tree[_, _]) = tree.root eq null + def clear(tree: Tree[_, _]): Unit = { tree.root = null; tree.size = 0 } + + // ---- search ---- + + def get[A: Ordering, B](tree: Tree[A, B], key: A): Option[B] = getNode(tree.root, key) match { + case null => None + case node => Some(node.value) + } + + @tailrec private[this] def getNode[A, B](node: Node[A, B], key: A)(implicit ord: Ordering[A]): Node[A, B] = + if (node eq null) null + else { + val cmp = ord.compare(key, node.key) + if (cmp < 0) getNode(node.left, key) + else if (cmp > 0) getNode(node.right, key) + else node + } + + def contains[A: Ordering](tree: Tree[A, _], key: A): Boolean = getNode(tree.root, key) ne null + + def min[A, B](tree: Tree[A, B]): Option[(A, B)] = minNode(tree.root) match { + case null => None + case node => Some((node.key, node.value)) + } + + def minKey[A](tree: Tree[A, _]): Option[A] = minNode(tree.root) match { + case null => None + case node => Some(node.key) + } + + private def minNode[A, B](node: Node[A, B]): Node[A, B] = + if (node eq null) null else minNodeNonNull(node) + + @tailrec def minNodeNonNull[A, B](node: Node[A, B]): Node[A, B] = + if (node.left eq null) node else minNodeNonNull(node.left) + + def max[A, B](tree: Tree[A, B]): Option[(A, B)] = maxNode(tree.root) match { + case null => None + case node => Some((node.key, node.value)) + } + + def maxKey[A](tree: Tree[A, _]): Option[A] = maxNode(tree.root) match { + case null => None + case node => Some(node.key) + } + + private def maxNode[A, B](node: Node[A, B]): Node[A, B] = + if (node eq null) null else maxNodeNonNull(node) + + @tailrec def maxNodeNonNull[A, B](node: Node[A, B]): Node[A, B] = + if (node.right eq null) node else maxNodeNonNull(node.right) + + /** + * Returns the first (lowest) map entry with a key equal or greater than `key`. Returns `None` if there is no such + * node. + */ + def minAfter[A, B](tree: Tree[A, B], key: A)(implicit ord: Ordering[A]): Option[(A, B)] = + minNodeAfter(tree.root, key) match { + case null => None + case node => Some((node.key, node.value)) + } + + def minKeyAfter[A](tree: Tree[A, _], key: A)(implicit ord: Ordering[A]): Option[A] = + minNodeAfter(tree.root, key) match { + case null => None + case node => Some(node.key) + } + + private[this] def minNodeAfter[A, B](node: Node[A, B], key: A)(implicit ord: Ordering[A]): Node[A, B] = { + if (node eq null) null + else { + var y: Node[A, B] = null + var x = node + var cmp = 1 + while ((x ne null) && cmp != 0) { + y = x + cmp = ord.compare(key, x.key) + x = if (cmp < 0) x.left else x.right + } + if (cmp <= 0) y else successor(y) + } + } + + /** + * Returns the last (highest) map entry with a key smaller than `key`. Returns `None` if there is no such node. + */ + def maxBefore[A, B](tree: Tree[A, B], key: A)(implicit ord: Ordering[A]): Option[(A, B)] = + maxNodeBefore(tree.root, key) match { + case null => None + case node => Some((node.key, node.value)) + } + + def maxKeyBefore[A](tree: Tree[A, _], key: A)(implicit ord: Ordering[A]): Option[A] = + maxNodeBefore(tree.root, key) match { + case null => None + case node => Some(node.key) + } + + private[this] def maxNodeBefore[A, B](node: Node[A, B], key: A)(implicit ord: Ordering[A]): Node[A, B] = { + if (node eq null) null + else { + var y: Node[A, B] = null + var x = node + var cmp = 1 + while ((x ne null) && cmp != 0) { + y = x + cmp = ord.compare(key, x.key) + x = if (cmp < 0) x.left else x.right + } + if (cmp > 0) y else predecessor(y) + } + } + + // ---- insertion ---- + + def insert[sealed A, sealed B](tree: Tree[A, B], key: A, value: B)(implicit ord: Ordering[A]): Unit = { + var y: Node[A, B] = null + var x = tree.root + var cmp = 1 + while ((x ne null) && cmp != 0) { + y = x + cmp = ord.compare(key, x.key) + x = if (cmp < 0) x.left else x.right + } + + if (cmp == 0) y.value = value + else { + val z = Node.leaf(key, value, red = true, y) + + if (y eq null) tree.root = z + else if (cmp < 0) y.left = z + else y.right = z + + fixAfterInsert(tree, z) + tree.size += 1 + } + } + + private[this] def fixAfterInsert[A, B](tree: Tree[A, B], node: Node[A, B]): Unit = { + var z = node + while (isRed(z.parent)) { + if (z.parent eq z.parent.parent.left) { + val y = z.parent.parent.right + if (isRed(y)) { + z.parent.red = false + y.red = false + z.parent.parent.red = true + z = z.parent.parent + } else { + if (z eq z.parent.right) { + z = z.parent + rotateLeft(tree, z) + } + z.parent.red = false + z.parent.parent.red = true + rotateRight(tree, z.parent.parent) + } + } else { // symmetric cases + val y = z.parent.parent.left + if (isRed(y)) { + z.parent.red = false + y.red = false + z.parent.parent.red = true + z = z.parent.parent + } else { + if (z eq z.parent.left) { + z = z.parent + rotateRight(tree, z) + } + z.parent.red = false + z.parent.parent.red = true + rotateLeft(tree, z.parent.parent) + } + } + } + tree.root.red = false + } + + // ---- deletion ---- + + def delete[A, B](tree: Tree[A, B], key: A)(implicit ord: Ordering[A]): Unit = { + val z = getNode(tree.root, key) + if (z ne null) { + var y = z + var yIsRed = y.red + var x: Node[A, B] = null + var xParent: Node[A, B] = null + + if (z.left eq null) { + x = z.right + transplant(tree, z, z.right) + xParent = z.parent + } + else if (z.right eq null) { + x = z.left + transplant(tree, z, z.left) + xParent = z.parent + } + else { + y = minNodeNonNull(z.right) + yIsRed = y.red + x = y.right + + if (y.parent eq z) xParent = y + else { + xParent = y.parent + transplant(tree, y, y.right) + y.right = z.right + y.right.parent = y + } + transplant(tree, z, y) + y.left = z.left + y.left.parent = y + y.red = z.red + } + + if (!yIsRed) fixAfterDelete(tree, x, xParent) + tree.size -= 1 + } + } + + private[this] def fixAfterDelete[A, B](tree: Tree[A, B], node: Node[A, B], parent: Node[A, B]): Unit = { + var x = node + var xParent = parent + while ((x ne tree.root) && isBlack(x)) { + if (x eq xParent.left) { + var w = xParent.right + // assert(w ne null) + + if (w.red) { + w.red = false + xParent.red = true + rotateLeft(tree, xParent) + w = xParent.right + } + if (isBlack(w.left) && isBlack(w.right)) { + w.red = true + x = xParent + } else { + if (isBlack(w.right)) { + w.left.red = false + w.red = true + rotateRight(tree, w) + w = xParent.right + } + w.red = xParent.red + xParent.red = false + w.right.red = false + rotateLeft(tree, xParent) + x = tree.root + } + } else { // symmetric cases + var w = xParent.left + // assert(w ne null) + + if (w.red) { + w.red = false + xParent.red = true + rotateRight(tree, xParent) + w = xParent.left + } + if (isBlack(w.right) && isBlack(w.left)) { + w.red = true + x = xParent + } else { + if (isBlack(w.left)) { + w.right.red = false + w.red = true + rotateLeft(tree, w) + w = xParent.left + } + w.red = xParent.red + xParent.red = false + w.left.red = false + rotateRight(tree, xParent) + x = tree.root + } + } + xParent = x.parent + } + if (x ne null) x.red = false + } + + // ---- helpers ---- + + /** + * Returns the node that follows `node` in an in-order tree traversal. If `node` has the maximum key (and is, + * therefore, the last node), this method returns `null`. + */ + private[this] def successor[A, B](node: Node[A, B]): Node[A, B] = { + if (node.right ne null) minNodeNonNull(node.right) + else { + var x = node + var y = x.parent + while ((y ne null) && (x eq y.right)) { + x = y + y = y.parent + } + y + } + } + + /** + * Returns the node that precedes `node` in an in-order tree traversal. If `node` has the minimum key (and is, + * therefore, the first node), this method returns `null`. + */ + private[this] def predecessor[A, B](node: Node[A, B]): Node[A, B] = { + if (node.left ne null) maxNodeNonNull(node.left) + else { + var x = node + var y = x.parent + while ((y ne null) && (x eq y.left)) { + x = y + y = y.parent + } + y + } + } + + private[this] def rotateLeft[A, B](tree: Tree[A, B], x: Node[A, B]): Unit = if (x ne null) { + // assert(x.right ne null) + val y = x.right + x.right = y.left + + if (y.left ne null) y.left.parent = x + y.parent = x.parent + + if (x.parent eq null) tree.root = y + else if (x eq x.parent.left) x.parent.left = y + else x.parent.right = y + + y.left = x + x.parent = y + } + + private[this] def rotateRight[A, B](tree: Tree[A, B], x: Node[A, B]): Unit = if (x ne null) { + // assert(x.left ne null) + val y = x.left + x.left = y.right + + if (y.right ne null) y.right.parent = x + y.parent = x.parent + + if (x.parent eq null) tree.root = y + else if (x eq x.parent.right) x.parent.right = y + else x.parent.left = y + + y.right = x + x.parent = y + } + + /** + * Transplant the node `from` to the place of node `to`. This is done by setting `from` as a child of `to`'s previous + * parent and setting `from`'s parent to the `to`'s previous parent. The children of `from` are left unchanged. + */ + private[this] def transplant[A, B](tree: Tree[A, B], to: Node[A, B], from: Node[A, B]): Unit = { + if (to.parent eq null) tree.root = from + else if (to eq to.parent.left) to.parent.left = from + else to.parent.right = from + + if (from ne null) from.parent = to.parent + } + + // ---- tree traversal ---- + + def foreach[A, B, U](tree: Tree[A, B], f: ((A, B)) => U): Unit = foreachNode(tree.root, f) + + private[this] def foreachNode[A, B, U](node: Node[A, B], f: ((A, B)) => U): Unit = + if (node ne null) foreachNodeNonNull(node, f) + + private[this] def foreachNodeNonNull[A, B, U](node: Node[A, B], f: ((A, B)) => U): Unit = { + if (node.left ne null) foreachNodeNonNull(node.left, f) + f((node.key, node.value)) + if (node.right ne null) foreachNodeNonNull(node.right, f) + } + + def foreachKey[A, U](tree: Tree[A, _], f: A => U): Unit = { + def g(node: Node[A, _]): Unit = { + val l = node.left + if(l ne null) g(l) + f(node.key) + val r = node.right + if(r ne null) g(r) + } + val r = tree.root + if(r ne null) g(r) + } + + def foreachEntry[A, B, U](tree: Tree[A, B], f: (A, B) => U): Unit = { + def g(node: Node[A, B]): Unit = { + val l = node.left + if(l ne null) g(l) + f(node.key, node.value) + val r = node.right + if(r ne null) g(r) + } + val r = tree.root + if(r ne null) g(r) + } + + def transform[A, B](tree: Tree[A, B], f: (A, B) => B): Unit = transformNode(tree.root, f) + + private[this] def transformNode[A, B, U](node: Node[A, B], f: (A, B) => B): Unit = + if (node ne null) transformNodeNonNull(node, f) + + private[this] def transformNodeNonNull[A, B, U](node: Node[A, B], f: (A, B) => B): Unit = { + if (node.left ne null) transformNodeNonNull(node.left, f) + node.value = f(node.key, node.value) + if (node.right ne null) transformNodeNonNull(node.right, f) + } + + def iterator[sealed A: Ordering, sealed B](tree: Tree[A, B], start: Option[A] = None, end: Option[A] = None): Iterator[(A, B)] = + new EntriesIterator(tree, start, end) + + def keysIterator[sealed A: Ordering](tree: Tree[A, _], start: Option[A] = None, end: Option[A] = None): Iterator[A] = + new KeysIterator(tree, start, end) + + def valuesIterator[sealed A: Ordering, sealed B](tree: Tree[A, B], start: Option[A] = None, end: Option[A] = None): Iterator[B] = + new ValuesIterator(tree, start, end) + + private[this] abstract class TreeIterator[sealed A, sealed B, R](tree: Tree[A, B], start: Option[A], end: Option[A]) + (implicit ord: Ordering[A]) extends AbstractIterator[R] { + + protected def nextResult(node: Node[A, B]): R + + def hasNext: Boolean = nextNode ne null + + @throws[NoSuchElementException] + def next(): R = nextNode match { + case null => throw new NoSuchElementException("next on empty iterator") + case node => + nextNode = successor(node) + setNullIfAfterEnd() + nextResult(node) + } + + private[this] var nextNode: Node[A, B] = start match { + case None => minNode(tree.root) + case Some(from) => minNodeAfter(tree.root, from) + } + + private[this] def setNullIfAfterEnd(): Unit = + if (end.isDefined && (nextNode ne null) && ord.compare(nextNode.key, end.get) >= 0) + nextNode = null + + setNullIfAfterEnd() + } + + private[this] final class EntriesIterator[sealed A: Ordering, sealed B](tree: Tree[A, B], start: Option[A], end: Option[A]) + extends TreeIterator[A, B, (A, B)](tree, start, end) { + + def nextResult(node: Node[A, B]) = (node.key, node.value) + } + + private[this] final class KeysIterator[sealed A: Ordering, sealed B](tree: Tree[A, B], start: Option[A], end: Option[A]) + extends TreeIterator[A, B, A](tree, start, end) { + + def nextResult(node: Node[A, B]) = node.key + } + + private[this] final class ValuesIterator[sealed A: Ordering, sealed B](tree: Tree[A, B], start: Option[A], end: Option[A]) + extends TreeIterator[A, B, B](tree, start, end) { + + def nextResult(node: Node[A, B]) = node.value + } + + // ---- debugging ---- + + /** + * Checks if the tree is in a valid state. That happens if: + * - It is a valid binary search tree; + * - All red-black properties are satisfied; + * - All non-null nodes have their `parent` reference correct; + * - The size variable in `tree` corresponds to the actual size of the tree. + */ + def isValid[A: Ordering, B](tree: Tree[A, B]): Boolean = + isValidBST(tree.root) && hasProperParentRefs(tree) && isValidRedBlackTree(tree) && size(tree.root) == tree.size + + /** + * Returns true if all non-null nodes have their `parent` reference correct. + */ + private[this] def hasProperParentRefs[A, B](tree: Tree[A, B]): Boolean = { + + def hasProperParentRefs(node: Node[A, B]): Boolean = { + if (node eq null) true + else { + if ((node.left ne null) && (node.left.parent ne node) || + (node.right ne null) && (node.right.parent ne node)) false + else hasProperParentRefs(node.left) && hasProperParentRefs(node.right) + } + } + + if(tree.root eq null) true + else (tree.root.parent eq null) && hasProperParentRefs(tree.root) + } + + /** + * Returns true if this node follows the properties of a binary search tree. + */ + private[this] def isValidBST[A, B](node: Node[A, B])(implicit ord: Ordering[A]): Boolean = { + if (node eq null) true + else { + if ((node.left ne null) && (ord.compare(node.key, node.left.key) <= 0) || + (node.right ne null) && (ord.compare(node.key, node.right.key) >= 0)) false + else isValidBST(node.left) && isValidBST(node.right) + } + } + + /** + * Returns true if the tree has all the red-black tree properties: if the root node is black, if all children of red + * nodes are black and if the path from any node to any of its null children has the same number of black nodes. + */ + private[this] def isValidRedBlackTree[A, B](tree: Tree[A, B]): Boolean = { + + def noRedAfterRed(node: Node[A, B]): Boolean = { + if (node eq null) true + else if (node.red && (isRed(node.left) || isRed(node.right))) false + else noRedAfterRed(node.left) && noRedAfterRed(node.right) + } + + def blackHeight(node: Node[A, B]): Int = { + if (node eq null) 1 + else { + val lh = blackHeight(node.left) + val rh = blackHeight(node.right) + + if (lh == -1 || lh != rh) -1 + else if (isRed(node)) lh + else lh + 1 + } + } + + isBlack(tree.root) && noRedAfterRed(tree.root) && blackHeight(tree.root) >= 0 + } + + // building + + /** Build a Tree suitable for a TreeSet from an ordered sequence of keys */ + def fromOrderedKeys[sealed A](xs: Iterator[A], size: Int): Tree[A, Null] = { + val maxUsedDepth = 32 - Integer.numberOfLeadingZeros(size) // maximum depth of non-leaf nodes + def f(level: Int, size: Int): Node[A, Null] = size match { + case 0 => null + case 1 => new Node(xs.next(), null, level == maxUsedDepth && level != 1, null, null, null) + case n => + val leftSize = (size-1)/2 + val left = f(level+1, leftSize) + val x = xs.next() + val right = f(level+1, size-1-leftSize) + val n = new Node(x, null, false, left, right, null) + if(left ne null) left.parent = n + right.parent = n + n + } + new Tree(f(1, size), size) + } + + /** Build a Tree suitable for a TreeMap from an ordered sequence of key/value pairs */ + def fromOrderedEntries[sealed A, sealed B](xs: Iterator[(A, B)], size: Int): Tree[A, B] = { + val maxUsedDepth = 32 - Integer.numberOfLeadingZeros(size) // maximum depth of non-leaf nodes + def f(level: Int, size: Int): Node[A, B] = size match { + case 0 => null + case 1 => + val (k, v) = xs.next() + new Node(k, v, level == maxUsedDepth && level != 1, null, null, null) + case n => + val leftSize = (size-1)/2 + val left = f(level+1, leftSize) + val (k, v) = xs.next() + val right = f(level+1, size-1-leftSize) + val n = new Node(k, v, false, left, right, null) + if(left ne null) left.parent = n + right.parent = n + n + } + new Tree(f(1, size), size) + } + + def copyTree[sealed A, sealed B](n: Node[A, B]): Node[A, B] = + if(n eq null) null else { + val c = new Node(n.key, n.value, n.red, copyTree(n.left), copyTree(n.right), null) + if(c.left != null) c.left.parent = c + if(c.right != null) c.right.parent = c + c + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/TreeMap.scala b/tests/pos-special/stdlib/collection/mutable/TreeMap.scala new file mode 100644 index 000000000000..f714a9ed46c2 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/TreeMap.scala @@ -0,0 +1,258 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.mutable.{RedBlackTree => RB} +import language.experimental.captureChecking + +/** + * A mutable sorted map implemented using a mutable red-black tree as underlying data structure. + * + * @param ordering the implicit ordering used to compare objects of type `A`. + * @tparam K the type of the keys contained in this tree map. + * @tparam V the type of the values associated with the keys. + * + * @define Coll mutable.TreeMap + * @define coll mutable tree map + */ +sealed class TreeMap[sealed K, sealed V] private (tree: RB.Tree[K, V])(implicit val ordering: Ordering[K]) + extends AbstractMap[K, V] + with SortedMap[K, V] + with SortedMapOps[K, V, TreeMap, TreeMap[K, V]] + with StrictOptimizedIterableOps[(K, V), Iterable, TreeMap[K, V]] + with StrictOptimizedMapOps[K, V, Map, TreeMap[K, V]] + with StrictOptimizedSortedMapOps[K, V, TreeMap, TreeMap[K, V]] + with SortedMapFactoryDefaults[K, V, TreeMap, Iterable, Map] + with DefaultSerializable { + + override def sortedMapFactory = TreeMap + + /** + * Creates an empty `TreeMap`. + * @param ord the implicit ordering used to compare objects of type `K`. + * @return an empty `TreeMap`. + */ + def this()(implicit ord: Ordering[K]) = this(RB.Tree.empty)(ord) + + def iterator: Iterator[(K, V)] = { + if (isEmpty) Iterator.empty + else RB.iterator(tree) + } + + override def keysIterator: Iterator[K] = { + if (isEmpty) Iterator.empty + else RB.keysIterator(tree, None) + } + + override def valuesIterator: Iterator[V] = { + if (isEmpty) Iterator.empty + else RB.valuesIterator(tree, None) + } + + def keysIteratorFrom(start: K): Iterator[K] = { + if (isEmpty) Iterator.empty + else RB.keysIterator(tree, Some(start)) + } + + def iteratorFrom(start: K): Iterator[(K, V)] = { + if (isEmpty) Iterator.empty + else RB.iterator(tree, Some(start)) + } + + override def valuesIteratorFrom(start: K): Iterator[V] = { + if (isEmpty) Iterator.empty + else RB.valuesIterator(tree, Some(start)) + } + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[(K, V), S]): S with EfficientSplit = + shape.parUnbox( + scala.collection.convert.impl.AnyBinaryTreeStepper.from[(K, V), RB.Node[K, V]]( + size, tree.root, _.left, _.right, x => (x.key, x.value) + ) + ) + + override def keyStepper[S <: Stepper[_]](implicit shape: StepperShape[K, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + type T = RB.Node[K, V] + val s = shape.shape match { + case StepperShape.IntShape => IntBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.key.asInstanceOf[Int]) + case StepperShape.LongShape => LongBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.key.asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleBinaryTreeStepper.from[T](size, tree.root, _.left, _.right, _.key.asInstanceOf[Double]) + case _ => shape.parUnbox(AnyBinaryTreeStepper.from[K, T](size, tree.root, _.left, _.right, _.key)) + } + s.asInstanceOf[S with EfficientSplit] + } + + override def valueStepper[S <: Stepper[_]](implicit shape: StepperShape[V, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + type T = RB.Node[K, V] + val s = shape.shape match { + case StepperShape.IntShape => IntBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.value.asInstanceOf[Int]) + case StepperShape.LongShape => LongBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.value.asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleBinaryTreeStepper.from[T] (size, tree.root, _.left, _.right, _.value.asInstanceOf[Double]) + case _ => shape.parUnbox(AnyBinaryTreeStepper.from[V, T] (size, tree.root, _.left, _.right, _.value)) + } + s.asInstanceOf[S with EfficientSplit] + } + + def addOne(elem: (K, V)): this.type = { RB.insert(tree, elem._1, elem._2); this } + + def subtractOne(elem: K): this.type = { RB.delete(tree, elem); this } + + override def clear(): Unit = RB.clear(tree) + + def get(key: K): Option[V] = RB.get(tree, key) + + /** + * Creates a ranged projection of this map. Any mutations in the ranged projection will update the original map and + * vice versa. + * + * Only entries with keys between this projection's key range will ever appear as elements of this map, independently + * of whether the entries are added through the original map or through this view. That means that if one inserts a + * key-value in a view whose key is outside the view's bounds, calls to `get` or `contains` will _not_ consider the + * newly added entry. Mutations are always reflected in the original map, though. + * + * @param from the lower bound (inclusive) of this projection wrapped in a `Some`, or `None` if there is no lower + * bound. + * @param until the upper bound (exclusive) of this projection wrapped in a `Some`, or `None` if there is no upper + * bound. + */ + def rangeImpl(from: Option[K], until: Option[K]): TreeMap[K, V] = new TreeMapProjection(from, until) + + override def foreach[U](f: ((K, V)) => U): Unit = RB.foreach(tree, f) + override def foreachEntry[U](f: (K, V) => U): Unit = RB.foreachEntry(tree, f) + + override def size: Int = RB.size(tree) + override def knownSize: Int = size + override def isEmpty: Boolean = RB.isEmpty(tree) + + override def contains(key: K): Boolean = RB.contains(tree, key) + + override def head: (K, V) = RB.min(tree).get + + override def last: (K, V) = RB.max(tree).get + + override def minAfter(key: K): Option[(K, V)] = RB.minAfter(tree, key) + + override def maxBefore(key: K): Option[(K, V)] = RB.maxBefore(tree, key) + + override protected[this] def className: String = "TreeMap" + + + /** + * A ranged projection of a [[TreeMap]]. Mutations on this map affect the original map and vice versa. + * + * Only entries with keys between this projection's key range will ever appear as elements of this map, independently + * of whether the entries are added through the original map or through this view. That means that if one inserts a + * key-value in a view whose key is outside the view's bounds, calls to `get` or `contains` will _not_ consider the + * newly added entry. Mutations are always reflected in the original map, though. + * + * @param from the lower bound (inclusive) of this projection wrapped in a `Some`, or `None` if there is no lower + * bound. + * @param until the upper bound (exclusive) of this projection wrapped in a `Some`, or `None` if there is no upper + * bound. + */ + private[this] final class TreeMapProjection(from: Option[K], until: Option[K]) extends TreeMap[K, V](tree) { + + /** + * Given a possible new lower bound, chooses and returns the most constraining one (the maximum). + */ + private[this] def pickLowerBound(newFrom: Option[K]): Option[K] = (from, newFrom) match { + case (Some(fr), Some(newFr)) => Some(ordering.max(fr, newFr)) + case (None, _) => newFrom + case _ => from + } + + /** + * Given a possible new upper bound, chooses and returns the most constraining one (the minimum). + */ + private[this] def pickUpperBound(newUntil: Option[K]): Option[K] = (until, newUntil) match { + case (Some(unt), Some(newUnt)) => Some(ordering.min(unt, newUnt)) + case (None, _) => newUntil + case _ => until + } + + /** + * Returns true if the argument is inside the view bounds (between `from` and `until`). + */ + private[this] def isInsideViewBounds(key: K): Boolean = { + val afterFrom = from.isEmpty || ordering.compare(from.get, key) <= 0 + val beforeUntil = until.isEmpty || ordering.compare(key, until.get) < 0 + afterFrom && beforeUntil + } + + override def rangeImpl(from: Option[K], until: Option[K]): TreeMap[K, V] = + new TreeMapProjection(pickLowerBound(from), pickUpperBound(until)) + + override def get(key: K) = if (isInsideViewBounds(key)) RB.get(tree, key) else None + + override def iterator = if (RB.size(tree) == 0) Iterator.empty else RB.iterator(tree, from, until) + override def keysIterator: Iterator[K] = if (RB.size(tree) == 0) Iterator.empty else RB.keysIterator(tree, from, until) + override def valuesIterator: Iterator[V] = if (RB.size(tree) == 0) Iterator.empty else RB.valuesIterator(tree, from, until) + override def keysIteratorFrom(start: K) = if (RB.size(tree) == 0) Iterator.empty else RB.keysIterator(tree, pickLowerBound(Some(start)), until) + override def iteratorFrom(start: K) = if (RB.size(tree) == 0) Iterator.empty else RB.iterator(tree, pickLowerBound(Some(start)), until) + override def valuesIteratorFrom(start: K) = if (RB.size(tree) == 0) Iterator.empty else RB.valuesIterator(tree, pickLowerBound(Some(start)), until) + override def size = if (RB.size(tree) == 0) 0 else iterator.length + override def knownSize: Int = if (RB.size(tree) == 0) 0 else -1 + override def isEmpty = RB.size(tree) == 0 || !iterator.hasNext + override def contains(key: K) = isInsideViewBounds(key) && RB.contains(tree, key) + + override def head = headOption.get + override def headOption = { + val entry = if (from.isDefined) RB.minAfter(tree, from.get) else RB.min(tree) + (entry, until) match { + case (Some(e), Some(unt)) if ordering.compare(e._1, unt) >= 0 => None + case _ => entry + } + } + + override def last = lastOption.get + override def lastOption = { + val entry = if (until.isDefined) RB.maxBefore(tree, until.get) else RB.max(tree) + (entry, from) match { + case (Some(e), Some(fr)) if ordering.compare(e._1, fr) < 0 => None + case _ => entry + } + } + + // Using the iterator should be efficient enough; if performance is deemed a problem later, specialized + // `foreach(f, from, until)` and `transform(f, from, until)` methods can be created in `RedBlackTree`. See + // https://github.com/scala/scala/pull/4608#discussion_r34307985 for a discussion about this. + override def foreach[U](f: ((K, V)) => U): Unit = iterator.foreach(f) + + override def clone() = super.clone().rangeImpl(from, until) + } + +} + +/** + * $factoryInfo + * + * @define Coll mutable.TreeMap + * @define coll mutable tree map + */ +@SerialVersionUID(3L) +object TreeMap extends SortedMapFactory[TreeMap] { + + def from[sealed K : Ordering, sealed V](it: IterableOnce[(K, V)]^): TreeMap[K, V] = + Growable.from(empty[K, V], it) + + def empty[sealed K : Ordering, sealed V]: TreeMap[K, V] = new TreeMap[K, V]() + + def newBuilder[sealed K: Ordering, sealed V]: Builder[(K, V), TreeMap[K, V]] = new GrowableBuilder(empty[K, V]) + +} diff --git a/tests/pos-special/stdlib/collection/mutable/TreeSet.scala b/tests/pos-special/stdlib/collection/mutable/TreeSet.scala index 59c68a768351..9ba439bea041 100644 --- a/tests/pos-special/stdlib/collection/mutable/TreeSet.scala +++ b/tests/pos-special/stdlib/collection/mutable/TreeSet.scala @@ -29,7 +29,7 @@ import language.experimental.captureChecking * @define coll mutable tree set */ // Original API designed in part by Lucien Pereira -sealed class TreeSet[A] private (private val tree: RB.Tree[A, Null])(implicit val ordering: Ordering[A]) +sealed class TreeSet[sealed A] private (private val tree: RB.Tree[A, Null])(implicit val ordering: Ordering[A]) extends AbstractSet[A] with SortedSet[A] with SortedSetOps[A, TreeSet, TreeSet[A]] @@ -192,9 +192,9 @@ sealed class TreeSet[A] private (private val tree: RB.Tree[A, Null])(implicit va @SerialVersionUID(3L) object TreeSet extends SortedIterableFactory[TreeSet] { - def empty[A : Ordering]: TreeSet[A] = new TreeSet[A]() + def empty[sealed A : Ordering]: TreeSet[A] = new TreeSet[A]() - def from[E](it: IterableOnce[E]^)(implicit ordering: Ordering[E]): TreeSet[E] = + def from[sealed E](it: IterableOnce[E]^)(implicit ordering: Ordering[E]): TreeSet[E] = it match { case ts: TreeSet[E] if ordering == ts.ordering => new TreeSet[E](ts.tree.treeCopy()) @@ -210,7 +210,7 @@ object TreeSet extends SortedIterableFactory[TreeSet] { new TreeSet[E](t) } - def newBuilder[A](implicit ordering: Ordering[A]): Builder[A, TreeSet[A]] = new ReusableBuilder[A, TreeSet[A]] { + def newBuilder[sealed A](implicit ordering: Ordering[A]): Builder[A, TreeSet[A]] = new ReusableBuilder[A, TreeSet[A]] { private[this] var tree: RB.Tree[A, Null] = RB.Tree.empty def addOne(elem: A): this.type = { RB.insert(tree, elem, null); this } def result(): TreeSet[A] = new TreeSet[A](tree) From 0888c408a1298c3db462a0099e03836cf073c466 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 17:57:00 +0100 Subject: [PATCH 51/89] Add mutable SortedMap and SeqMap to stdlib --- .../stdlib/collection/mutable/SeqMap.scala | 39 +++++++ .../stdlib/collection/mutable/SortedMap.scala | 104 ++++++++++++++++++ 2 files changed, 143 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/SeqMap.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/SortedMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/SeqMap.scala b/tests/pos-special/stdlib/collection/mutable/SeqMap.scala new file mode 100644 index 000000000000..5740490223b2 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/SeqMap.scala @@ -0,0 +1,39 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable +import language.experimental.captureChecking + +/** + * A generic trait for ordered mutable maps. Concrete classes have to provide + * functionality for the abstract methods in `SeqMap`. + * + * Note that when checking for equality [[SeqMap]] does not take into account + * ordering. + * + * @tparam K the type of the keys contained in this linked map. + * @tparam V the type of the values associated with the keys in this linked map. + * + * @define coll mutable Seq map + * @define Coll `mutable.SeqMap` + */ + +trait SeqMap[K, V] extends Map[K, V] + with collection.SeqMap[K, V] + with MapOps[K, V, SeqMap, SeqMap[K, V]] + with MapFactoryDefaults[K, V, SeqMap, Iterable] { + override def mapFactory: MapFactory[SeqMap] = SeqMap +} + +object SeqMap extends MapFactory.Delegate[SeqMap](LinkedHashMap) diff --git a/tests/pos-special/stdlib/collection/mutable/SortedMap.scala b/tests/pos-special/stdlib/collection/mutable/SortedMap.scala new file mode 100644 index 000000000000..ff0e95c747a5 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/SortedMap.scala @@ -0,0 +1,104 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.mutable + +import scala.collection.{SortedMapFactory, SortedMapFactoryDefaults} +import language.experimental.captureChecking + +/** + * Base type for mutable sorted map collections + */ +trait SortedMap[K, V] + extends collection.SortedMap[K, V] + with Map[K, V] + with SortedMapOps[K, V, SortedMap, SortedMap[K, V]] + with SortedMapFactoryDefaults[K, V, SortedMap, Iterable, Map] { + + override def unsorted: Map[K, V] = this + + override def sortedMapFactory: SortedMapFactory[SortedMap] = SortedMap + + /** The same sorted map with a given default function. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefault`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d the function mapping keys to values, used for non-present keys + * @return a wrapper of the map with a default value + */ + override def withDefault(d: K -> V): SortedMap[K, V] = new SortedMap.WithDefault[K, V](this, d) + + /** The same map with a given default value. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefaultValue`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d default value used for non-present keys + * @return a wrapper of the map with a default value + */ + override def withDefaultValue(d: V): SortedMap[K, V] = new SortedMap.WithDefault[K, V](this, _ => d) +} + +trait SortedMapOps[K, V, +CC[X, Y] <: Map[X, Y] with SortedMapOps[X, Y, CC, _], +C <: SortedMapOps[K, V, CC, C]] + extends collection.SortedMapOps[K, V, CC, C] + with MapOps[K, V, Map, C] { + + def unsorted: Map[K, V] + + @deprecated("Use m.clone().addOne((k,v)) instead of m.updated(k, v)", "2.13.0") + override def updated[V1 >: V](key: K, value: V1): CC[K, V1] = + clone().asInstanceOf[CC[K, V1]].addOne((key, value)) +} + +@SerialVersionUID(3L) +object SortedMap extends SortedMapFactory.Delegate[SortedMap](TreeMap) { + + @SerialVersionUID(3L) + final class WithDefault[K, V](underlying: SortedMap[K, V], defaultValue: K -> V) + extends Map.WithDefault[K, V](underlying, defaultValue) + with SortedMap[K, V] + with SortedMapOps[K, V, SortedMap, WithDefault[K, V]] + with Serializable { + + override def sortedMapFactory: SortedMapFactory[SortedMap] = underlying.sortedMapFactory + + def iteratorFrom(start: K): scala.collection.Iterator[(K, V)] = underlying.iteratorFrom(start) + + def keysIteratorFrom(start: K): scala.collection.Iterator[K] = underlying.keysIteratorFrom(start) + + implicit def ordering: Ordering[K] = underlying.ordering + + def rangeImpl(from: Option[K], until: Option[K]): WithDefault[K, V] = + new WithDefault[K, V](underlying.rangeImpl(from, until), defaultValue) + + // Need to override following methods to match type signatures of `SortedMap.WithDefault` + // for operations preserving default value + override def subtractOne(elem: K): WithDefault.this.type = { underlying.subtractOne(elem); this } + + override def addOne(elem: (K, V)): WithDefault.this.type = { underlying.addOne(elem); this } + + override def empty: WithDefault[K, V] = new WithDefault[K, V](underlying.empty, defaultValue) + + override def concat[V2 >: V](suffix: collection.IterableOnce[(K, V2)]): SortedMap[K, V2] = + underlying.concat(suffix).withDefault(defaultValue) + + override protected def fromSpecific(coll: scala.collection.IterableOnce[(K, V)]^): WithDefault[K, V] = + new WithDefault[K, V](sortedMapFactory.from(coll), defaultValue) + + override protected def newSpecificBuilder: Builder[(K, V), WithDefault[K, V]] = + SortedMap.newBuilder.mapResult((p: SortedMap[K, V]) => new WithDefault[K, V](p, defaultValue)) + } +} From a76129f308e7561231a24df21747e9826e5198f3 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 18:11:45 +0100 Subject: [PATCH 52/89] Add AnyRefMap to stdlib --- .../stdlib/collection/mutable/AnyRefMap.scala | 603 ++++++++++++++++++ 1 file changed, 603 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/AnyRefMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/AnyRefMap.scala b/tests/pos-special/stdlib/collection/mutable/AnyRefMap.scala new file mode 100644 index 000000000000..a6413649e219 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/AnyRefMap.scala @@ -0,0 +1,603 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package mutable + +import scala.annotation.nowarn +import scala.collection.generic.DefaultSerializationProxy +import scala.language.implicitConversions +import language.experimental.captureChecking + + +/** This class implements mutable maps with `AnyRef` keys based on a hash table with open addressing. + * + * Basic map operations on single entries, including `contains` and `get`, + * are typically significantly faster with `AnyRefMap` than [[HashMap]]. + * Note that numbers and characters are not handled specially in AnyRefMap; + * only plain `equals` and `hashCode` are used in comparisons. + * + * Methods that traverse or regenerate the map, including `foreach` and `map`, + * are not in general faster than with `HashMap`. The methods `foreachKey`, + * `foreachValue`, `mapValuesNow`, and `transformValues` are, however, faster + * than alternative ways to achieve the same functionality. + * + * Maps with open addressing may become less efficient at lookup after + * repeated addition/removal of elements. Although `AnyRefMap` makes a + * decent attempt to remain efficient regardless, calling `repack` + * on a map that will no longer have elements removed but will be + * used heavily may save both time and storage space. + * + * This map is not intended to contain more than 2^29^ entries (approximately + * 500 million). The maximum capacity is 2^30^, but performance will degrade + * rapidly as 2^30^ is approached. + * + */ +class AnyRefMap[K <: AnyRef, sealed V] private[collection] (defaultEntry: K -> V, initialBufferSize: Int, initBlank: Boolean) + extends AbstractMap[K, V] + with MapOps[K, V, Map, AnyRefMap[K, V]] + with StrictOptimizedIterableOps[(K, V), Iterable, AnyRefMap[K, V]] + with Serializable { + + import AnyRefMap._ + def this() = this(AnyRefMap.exceptionDefault, 16, true) + + /** Creates a new `AnyRefMap` that returns default values according to a supplied key-value mapping. */ + def this(defaultEntry: K -> V) = this(defaultEntry, 16, true) + + /** Creates a new `AnyRefMap` with an initial buffer of specified size. + * + * An `AnyRefMap` can typically contain half as many elements as its buffer size + * before it requires resizing. + */ + def this(initialBufferSize: Int) = this(AnyRefMap.exceptionDefault, initialBufferSize, true) + + /** Creates a new `AnyRefMap` with specified default values and initial buffer size. */ + def this(defaultEntry: K -> V, initialBufferSize: Int) = this(defaultEntry, initialBufferSize, true) + + private[this] var mask = 0 + private[this] var _size = 0 + private[this] var _vacant = 0 + private[this] var _hashes: Array[Int] = null + private[this] var _keys: Array[AnyRef] = null + private[this] var _values: Array[AnyRef] = null + + if (initBlank) defaultInitialize(initialBufferSize) + + private[this] def defaultInitialize(n: Int): Unit = { + mask = + if (n<0) 0x7 + else (((1 << (32 - java.lang.Integer.numberOfLeadingZeros(n-1))) - 1) & 0x3FFFFFFF) | 0x7 + _hashes = new Array[Int](mask+1) + _keys = new Array[AnyRef](mask+1) + _values = new Array[AnyRef](mask+1) + } + + private[collection] def initializeTo( + m: Int, sz: Int, vc: Int, hz: Array[Int], kz: Array[AnyRef], vz: Array[AnyRef] + ): Unit = { + mask = m; _size = sz; _vacant = vc; _hashes = hz; _keys = kz; _values = vz + } + + override protected def fromSpecific(coll: scala.collection.IterableOnce[(K, V)]^): AnyRefMap[K,V] = { + var sz = coll.knownSize + if(sz < 0) sz = 4 + val arm = new AnyRefMap[K, V](sz * 2) + coll.iterator.foreach{ case (k,v) => arm(k) = v } + if (arm.size < (sz>>3)) arm.repack() + arm + } + override protected def newSpecificBuilder: Builder[(K, V), AnyRefMap[K,V]] = new AnyRefMapBuilder + + override def size: Int = _size + override def knownSize: Int = size + override def isEmpty: Boolean = _size == 0 + override def empty: AnyRefMap[K,V] = new AnyRefMap(defaultEntry) + + private def imbalanced: Boolean = + (_size + _vacant) > 0.5*mask || _vacant > _size + + private def hashOf(key: K): Int = { + // Note: this method must not return 0 or Int.MinValue, as these indicate no element + if (key eq null) 0x41081989 + else { + val h = key.hashCode + // Part of the MurmurHash3 32 bit finalizer + val i = (h ^ (h >>> 16)) * 0x85EBCA6B + val j = (i ^ (i >>> 13)) & 0x7FFFFFFF + if (j==0) 0x41081989 else j + } + } + + private def seekEntry(h: Int, k: AnyRef): Int = { + var e = h & mask + var x = 0 + var g = 0 + val hashes = _hashes + val keys = _keys + while ({ g = hashes(e); g != 0}) { + if (g == h && { val q = keys(e); (q eq k) || ((q ne null) && (q equals k)) }) return e + x += 1 + e = (e + 2*(x+1)*x - 3) & mask + } + e | MissingBit + } + + @`inline` private def seekEntryOrOpen(h: Int, k: AnyRef): Int = { + var e = h & mask + var x = 0 + var g = 0 + var o = -1 + while ({ g = _hashes(e); g != 0}) { + if (g == h && { val q = _keys(e); (q eq k) || ((q ne null) && (q equals k)) }) return e + else if (o == -1 && g+g == 0) o = e + x += 1 + e = (e + 2*(x+1)*x - 3) & mask + } + if (o >= 0) o | MissVacant else e | MissingBit + } + + override def contains(key: K): Boolean = seekEntry(hashOf(key), key) >= 0 + + override def get(key: K): Option[V] = { + val i = seekEntry(hashOf(key), key) + if (i < 0) None else Some(_values(i).asInstanceOf[V]) + } + + override def getOrElse[V1 >: V](key: K, default: => V1): V1 = { + val i = seekEntry(hashOf(key), key) + if (i < 0) default else _values(i).asInstanceOf[V] + } + + override def getOrElseUpdate(key: K, defaultValue: => V): V = { + val h = hashOf(key) + var i = seekEntryOrOpen(h, key) + if (i < 0) { + // It is possible that the default value computation was side-effecting + // Our hash table may have resized or even contain what we want now + // (but if it does, we'll replace it) + val value = { + val oh = _hashes + val ans = defaultValue + if (oh ne _hashes) { + i = seekEntryOrOpen(h, key) + if (i >= 0) _size -= 1 + } + ans + } + _size += 1 + val j = i & IndexMask + _hashes(j) = h + _keys(j) = key.asInstanceOf[AnyRef] + _values(j) = value.asInstanceOf[AnyRef] + if ((i & VacantBit) != 0) _vacant -= 1 + else if (imbalanced) repack() + value + } + else _values(i).asInstanceOf[V] + } + + /** Retrieves the value associated with a key, or the default for that type if none exists + * (null for AnyRef, 0 for floats and integers). + * + * Note: this is the fastest way to retrieve a value that may or + * may not exist, if the default null/zero is acceptable. For key/value + * pairs that do exist, `apply` (i.e. `map(key)`) is equally fast. + */ + def getOrNull(key: K): V = { + val i = seekEntry(hashOf(key), key) + (if (i < 0) null else _values(i)).asInstanceOf[V] + } + + /** Retrieves the value associated with a key. + * If the key does not exist in the map, the `defaultEntry` for that key + * will be returned instead; an exception will be thrown if no + * `defaultEntry` was supplied. + */ + override def apply(key: K): V = { + val i = seekEntry(hashOf(key), key) + if (i < 0) defaultEntry(key) else _values(i).asInstanceOf[V] + } + + /** Defers to defaultEntry to find a default value for the key. Throws an + * exception if no other default behavior was specified. + */ + override def default(key: K): V = defaultEntry(key) + + private def repack(newMask: Int): Unit = { + val oh = _hashes + val ok = _keys + val ov = _values + mask = newMask + _hashes = new Array[Int](mask+1) + _keys = new Array[AnyRef](mask+1) + _values = new Array[AnyRef](mask+1) + _vacant = 0 + var i = 0 + while (i < oh.length) { + val h = oh(i) + if (h+h != 0) { + var e = h & mask + var x = 0 + while (_hashes(e) != 0) { x += 1; e = (e + 2*(x+1)*x - 3) & mask } + _hashes(e) = h + _keys(e) = ok(i) + _values(e) = ov(i) + } + i += 1 + } + } + + /** Repacks the contents of this `AnyRefMap` for maximum efficiency of lookup. + * + * For maps that undergo a complex creation process with both addition and + * removal of keys, and then are used heavily with no further removal of + * elements, calling `repack` after the end of the creation can result in + * improved performance. Repacking takes time proportional to the number + * of entries in the map. + */ + def repack(): Unit = { + var m = mask + if (_size + _vacant >= 0.5*mask && !(_vacant > 0.2*mask)) m = ((m << 1) + 1) & IndexMask + while (m > 8 && 8*_size < m) m = m >>> 1 + repack(m) + } + + override def put(key: K, value: V): Option[V] = { + val h = hashOf(key) + val i = seekEntryOrOpen(h, key) + if (i < 0) { + val j = i & IndexMask + _hashes(j) = h + _keys(j) = key + _values(j) = value.asInstanceOf[AnyRef] + _size += 1 + if ((i & VacantBit) != 0) _vacant -= 1 + else if (imbalanced) repack() + None + } + else { + val ans = Some(_values(i).asInstanceOf[V]) + _hashes(i) = h + _values(i) = value.asInstanceOf[AnyRef] + ans + } + } + + /** Updates the map to include a new key-value pair. + * + * This is the fastest way to add an entry to an `AnyRefMap`. + */ + override def update(key: K, value: V): Unit = { + val h = hashOf(key) + val i = seekEntryOrOpen(h, key) + if (i < 0) { + val j = i & IndexMask + _hashes(j) = h + _keys(j) = key + _values(j) = value.asInstanceOf[AnyRef] + _size += 1 + if ((i & VacantBit) != 0) _vacant -= 1 + else if (imbalanced) repack() + } + else { + _hashes(i) = h + _values(i) = value.asInstanceOf[AnyRef] + } + } + + /** Adds a new key/value pair to this map and returns the map. */ + @deprecated("Use `addOne` or `update` instead; infix operations with an operand of multiple args will be deprecated", "2.13.3") + def +=(key: K, value: V): this.type = { update(key, value); this } + + /** Adds a new key/value pair to this map and returns the map. */ + @inline final def addOne(key: K, value: V): this.type = { update(key, value); this } + + @inline override final def addOne(kv: (K, V)): this.type = { update(kv._1, kv._2); this } + + def subtractOne(key: K): this.type = { + val i = seekEntry(hashOf(key), key) + if (i >= 0) { + _size -= 1 + _vacant += 1 + _hashes(i) = Int.MinValue + _keys(i) = null + _values(i) = null + } + this + } + + def iterator: Iterator[(K, V)] = new AnyRefMapIterator[(K, V)] { + protected def nextResult(k: K, v: V) = (k, v) + } + override def keysIterator: Iterator[K] = new AnyRefMapIterator[K] { + protected def nextResult(k: K, v: V) = k + } + override def valuesIterator: Iterator[V] = new AnyRefMapIterator[V] { + protected def nextResult(k: K, v: V) = v + } + + private abstract class AnyRefMapIterator[A] extends AbstractIterator[A] { + private[this] val hz = _hashes + private[this] val kz = _keys + private[this] val vz = _values + + private[this] var index = 0 + + def hasNext: Boolean = index= hz.length) return false + h = hz(index) + } + true + } + + def next(): A = { + if (hasNext) { + val ans = nextResult(kz(index).asInstanceOf[K], vz(index).asInstanceOf[V]) + index += 1 + ans + } + else throw new NoSuchElementException("next") + } + + protected def nextResult(k: K, v: V): A + } + + + override def foreach[U](f: ((K,V)) => U): Unit = { + var i = 0 + var e = _size + while (e > 0) { + while(i < _hashes.length && { val h = _hashes(i); h+h == 0 && i < _hashes.length}) i += 1 + if (i < _hashes.length) { + f((_keys(i).asInstanceOf[K], _values(i).asInstanceOf[V])) + i += 1 + e -= 1 + } + else return + } + } + + override def foreachEntry[U](f: (K,V) => U): Unit = { + var i = 0 + var e = _size + while (e > 0) { + while(i < _hashes.length && { val h = _hashes(i); h+h == 0 && i < _hashes.length}) i += 1 + if (i < _hashes.length) { + f(_keys(i).asInstanceOf[K], _values(i).asInstanceOf[V]) + i += 1 + e -= 1 + } + else return + } + } + + override def clone(): AnyRefMap[K, V] = { + val hz = java.util.Arrays.copyOf(_hashes, _hashes.length) + val kz = java.util.Arrays.copyOf(_keys, _keys.length) + val vz = java.util.Arrays.copyOf(_values, _values.length) + val arm = new AnyRefMap[K, V](defaultEntry, 1, false) + arm.initializeTo(mask, _size, _vacant, hz, kz, vz) + arm + } + + @deprecated("Consider requiring an immutable Map or fall back to Map.concat", "2.13.0") + override def + [sealed V1 >: V](kv: (K, V1)): AnyRefMap[K, V1] = AnyRefMap.from(new View.Appended(this, kv)) + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + override def + [sealed V1 >: V](elem1: (K, V1), elem2: (K, V1), elems: (K, V1)*): AnyRefMap[K, V1] = { + val m = this + elem1 + elem2 + if(elems.isEmpty) m else m.concat(elems) + } + + override def concat[sealed V2 >: V](xs: scala.collection.IterableOnce[(K, V2)]^): AnyRefMap[K, V2] = { + val arm = clone().asInstanceOf[AnyRefMap[K, V2]] + xs.iterator.foreach(kv => arm += kv) + arm + } + + override def ++[sealed V2 >: V](xs: scala.collection.IterableOnce[(K, V2)]^): AnyRefMap[K, V2] = concat(xs) + + @deprecated("Use m.clone().addOne(k,v) instead of m.updated(k, v)", "2.13.0") + override def updated[sealed V1 >: V](key: K, value: V1): AnyRefMap[K, V1] = + clone().asInstanceOf[AnyRefMap[K, V1]].addOne(key, value) + + private[this] def foreachElement[A,B](elems: Array[AnyRef], f: A => B): Unit = { + var i,j = 0 + while (i < _hashes.length & j < _size) { + val h = _hashes(i) + if (h+h != 0) { + j += 1 + f(elems(i).asInstanceOf[A]) + } + i += 1 + } + } + + /** Applies a function to all keys of this map. */ + def foreachKey[A](f: K => A): Unit = foreachElement[K,A](_keys, f) + + /** Applies a function to all values of this map. */ + def foreachValue[A](f: V => A): Unit = foreachElement[V,A](_values, f) + + /** Creates a new `AnyRefMap` with different values. + * Unlike `mapValues`, this method generates a new + * collection immediately. + */ + def mapValuesNow[sealed V1](f: V => V1): AnyRefMap[K, V1] = { + val arm = new AnyRefMap[K,V1](AnyRefMap.exceptionDefault, 1, false) + val hz = java.util.Arrays.copyOf(_hashes, _hashes.length) + val kz = java.util.Arrays.copyOf(_keys, _keys.length) + val vz = new Array[AnyRef](_values.length) + var i,j = 0 + while (i < _hashes.length & j < _size) { + val h = _hashes(i) + if (h+h != 0) { + j += 1 + vz(i) = f(_values(i).asInstanceOf[V]).asInstanceOf[AnyRef] + } + i += 1 + } + arm.initializeTo(mask, _size, _vacant, hz, kz, vz) + arm + } + + /** Applies a transformation function to all values stored in this map. + * Note: the default, if any, is not transformed. + */ + @deprecated("Use transformValuesInPlace instead of transformValues", "2.13.0") + @`inline` final def transformValues(f: V => V): this.type = transformValuesInPlace(f) + + /** Applies a transformation function to all values stored in this map. + * Note: the default, if any, is not transformed. + */ + def transformValuesInPlace(f: V => V): this.type = { + var i,j = 0 + while (i < _hashes.length & j < _size) { + val h = _hashes(i) + if (h+h != 0) { + j += 1 + _values(i) = f(_values(i).asInstanceOf[V]).asInstanceOf[AnyRef] + } + i += 1 + } + this + } + + // The implicit dummy parameter is necessary to distinguish these methods from the base methods they overload (not override) + def map[K2 <: AnyRef, sealed V2](f: ((K, V)) => (K2, V2))(implicit dummy: DummyImplicit): AnyRefMap[K2, V2] = + AnyRefMap.from(new View.Map(this, f)) + def flatMap[K2 <: AnyRef, sealed V2](f: ((K, V)) => IterableOnce[(K2, V2)])(implicit dummy: DummyImplicit): AnyRefMap[K2, V2] = + AnyRefMap.from(new View.FlatMap(this, f)) + def collect[K2 <: AnyRef, sealed V2](pf: PartialFunction[(K, V), (K2, V2)])(implicit dummy: DummyImplicit): AnyRefMap[K2, V2] = + strictOptimizedCollect(AnyRefMap.newBuilder[K2, V2], pf) + + override def clear(): Unit = { + import java.util.Arrays.fill + fill(_keys, null) + fill(_values, null) + fill(_hashes, 0) + _size = 0 + _vacant = 0 + } + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(AnyRefMap.toFactory[K, V](AnyRefMap), this) + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix = "AnyRefMap" +} + +object AnyRefMap { + private final val IndexMask = 0x3FFFFFFF + private final val MissingBit = 0x80000000 + private final val VacantBit = 0x40000000 + private final val MissVacant = 0xC0000000 + + private class ExceptionDefault extends (Any -> Nothing) with Serializable { + def apply(k: Any): Nothing = throw new NoSuchElementException(if (k == null) "(null)" else k.toString) + } + private val exceptionDefault = new ExceptionDefault + + /** A builder for instances of `AnyRefMap`. + * + * This builder can be reused to create multiple instances. + */ + final class AnyRefMapBuilder[K <: AnyRef, sealed V] extends ReusableBuilder[(K, V), AnyRefMap[K, V]] { + private[collection] var elems: AnyRefMap[K, V] = new AnyRefMap[K, V] + def addOne(entry: (K, V)): this.type = { + elems += entry + this + } + def clear(): Unit = elems = new AnyRefMap[K, V] + def result(): AnyRefMap[K, V] = elems + override def knownSize: Int = elems.knownSize + } + + /** Creates a new `AnyRefMap` with zero or more key/value pairs. */ + def apply[K <: AnyRef, sealed V](elems: (K, V)*): AnyRefMap[K, V] = buildFromIterableOnce(elems) + + def newBuilder[K <: AnyRef, sealed V]: ReusableBuilder[(K, V), AnyRefMap[K, V]] = new AnyRefMapBuilder[K, V] + + private def buildFromIterableOnce[K <: AnyRef, sealed V](elems: IterableOnce[(K, V)]^): AnyRefMap[K, V] = { + var sz = elems.knownSize + if(sz < 0) sz = 4 + val arm = new AnyRefMap[K, V](sz * 2) + elems.iterator.foreach{ case (k,v) => arm(k) = v } + if (arm.size < (sz>>3)) arm.repack() + arm + } + + /** Creates a new empty `AnyRefMap`. */ + def empty[K <: AnyRef, sealed V]: AnyRefMap[K, V] = new AnyRefMap[K, V] + + /** Creates a new empty `AnyRefMap` with the supplied default */ + def withDefault[K <: AnyRef, sealed V](default: K -> V): AnyRefMap[K, V] = new AnyRefMap[K, V](default) + + /** Creates a new `AnyRefMap` from an existing source collection. A source collection + * which is already an `AnyRefMap` gets cloned. + * + * @param source Source collection + * @tparam K the type of the keys + * @tparam V the type of the values + * @return a new `AnyRefMap` with the elements of `source` + */ + def from[K <: AnyRef, sealed V](source: IterableOnce[(K, V)]^): AnyRefMap[K, V] = source match { + case source: AnyRefMap[_, _] => source.clone().asInstanceOf[AnyRefMap[K, V]] + case _ => buildFromIterableOnce(source) + } + + /** Creates a new `AnyRefMap` from arrays of keys and values. + * Equivalent to but more efficient than `AnyRefMap((keys zip values): _*)`. + */ + def fromZip[K <: AnyRef, sealed V](keys: Array[K], values: Array[V]): AnyRefMap[K, V] = { + val sz = math.min(keys.length, values.length) + val arm = new AnyRefMap[K, V](sz * 2) + var i = 0 + while (i < sz) { arm(keys(i)) = values(i); i += 1 } + if (arm.size < (sz>>3)) arm.repack() + arm + } + + /** Creates a new `AnyRefMap` from keys and values. + * Equivalent to but more efficient than `AnyRefMap((keys zip values): _*)`. + */ + def fromZip[K <: AnyRef, sealed V](keys: Iterable[K]^, values: Iterable[V]^): AnyRefMap[K, V] = { + val sz = math.min(keys.size, values.size) + val arm = new AnyRefMap[K, V](sz * 2) + val ki = keys.iterator + val vi = values.iterator + while (ki.hasNext && vi.hasNext) arm(ki.next()) = vi.next() + if (arm.size < (sz >> 3)) arm.repack() + arm + } + + implicit def toFactory[K <: AnyRef, sealed V](dummy: AnyRefMap.type): Factory[(K, V), AnyRefMap[K, V]] = ToFactory.asInstanceOf[Factory[(K, V), AnyRefMap[K, V]]] + + @SerialVersionUID(3L) + private[this] object ToFactory extends Factory[(AnyRef, AnyRef), AnyRefMap[AnyRef, AnyRef]] with Serializable { + def fromSpecific(it: IterableOnce[(AnyRef, AnyRef)]^): AnyRefMap[AnyRef, AnyRef] = AnyRefMap.from[AnyRef, AnyRef](it) + def newBuilder: Builder[(AnyRef, AnyRef), AnyRefMap[AnyRef, AnyRef]] = AnyRefMap.newBuilder[AnyRef, AnyRef] + } + + implicit def toBuildFrom[K <: AnyRef, sealed V](factory: AnyRefMap.type): BuildFrom[Any, (K, V), AnyRefMap[K, V]] = ToBuildFrom.asInstanceOf[BuildFrom[Any, (K, V), AnyRefMap[K, V]]] + private[this] object ToBuildFrom extends BuildFrom[Any, (AnyRef, AnyRef), AnyRefMap[AnyRef, AnyRef]] { + def fromSpecific(from: Any)(it: IterableOnce[(AnyRef, AnyRef)]^) = AnyRefMap.from(it) + def newBuilder(from: Any) = AnyRefMap.newBuilder[AnyRef, AnyRef] + } + + implicit def iterableFactory[K <: AnyRef, sealed V]: Factory[(K, V), AnyRefMap[K, V]] = toFactory[K, V](this) + implicit def buildFromAnyRefMap[K <: AnyRef, sealed V]: BuildFrom[AnyRefMap[_, _], (K, V), AnyRefMap[K, V]] = toBuildFrom(this) +} From 73f9474beaf9621b958c8c9bada8cbd5806e5d3a Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 18:22:21 +0100 Subject: [PATCH 53/89] Add CollisionProofHashMap to stdlib --- .../stdlib/collection/mutable/Cloneable.scala | 22 + .../mutable/CollisionProofHashMap.scala | 889 ++++++++++++++++++ 2 files changed, 911 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/Cloneable.scala create mode 100644 tests/pos-special/stdlib/collection/mutable/CollisionProofHashMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/Cloneable.scala b/tests/pos-special/stdlib/collection/mutable/Cloneable.scala new file mode 100644 index 000000000000..39149e98cbf0 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/Cloneable.scala @@ -0,0 +1,22 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.mutable +import language.experimental.captureChecking + +/** A trait for cloneable collections. + * + * @tparam C Type of the collection, covariant and with reference types as upperbound. + */ +trait Cloneable[+C <: AnyRef] extends scala.Cloneable { + override def clone(): C = super.clone().asInstanceOf[C] +} diff --git a/tests/pos-special/stdlib/collection/mutable/CollisionProofHashMap.scala b/tests/pos-special/stdlib/collection/mutable/CollisionProofHashMap.scala new file mode 100644 index 000000000000..2b27efb6eac1 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/CollisionProofHashMap.scala @@ -0,0 +1,889 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.{unchecked => uc} +import scala.annotation.{implicitNotFound, tailrec, unused} +import scala.annotation.unchecked.uncheckedVariance +import scala.collection.generic.DefaultSerializationProxy +import scala.runtime.Statics +import language.experimental.captureChecking + +/** This class implements mutable maps using a hashtable with red-black trees in the buckets for good + * worst-case performance on hash collisions. An `Ordering` is required for the element type. Equality + * as determined by the `Ordering` has to be consistent with `equals` and `hashCode`. Universal equality + * of numeric types is not supported (similar to `AnyRefMap`). + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#hash-tables "Scala's Collection Library overview"]] + * section on `Hash Tables` for more information. + * + * @define Coll `mutable.CollisionProofHashMap` + * @define coll mutable collision-proof hash map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +final class CollisionProofHashMap[sealed K, sealed V](initialCapacity: Int, loadFactor: Double)(implicit ordering: Ordering[K]) + extends AbstractMap[K, V] + with MapOps[K, V, Map, CollisionProofHashMap[K, V]] //-- + with StrictOptimizedIterableOps[(K, V), Iterable, CollisionProofHashMap[K, V]] + with StrictOptimizedMapOps[K, V, Map, CollisionProofHashMap[K, V]] { //-- + + private[this] final def sortedMapFactory: SortedMapFactory[CollisionProofHashMap] = CollisionProofHashMap + + def this()(implicit ordering: Ordering[K]) = this(CollisionProofHashMap.defaultInitialCapacity, CollisionProofHashMap.defaultLoadFactor)(ordering) + + import CollisionProofHashMap.Node + private[this] type RBNode = CollisionProofHashMap.RBNode[K, V] + private[this] type LLNode = CollisionProofHashMap.LLNode[K, V] + + /** The actual hash table. */ + private[this] var table: Array[Node] = new Array[Node](tableSizeFor(initialCapacity)) + + /** The next size value at which to resize (capacity * load factor). */ + private[this] var threshold: Int = newThreshold(table.length) + + private[this] var contentSize = 0 + + override def size: Int = contentSize + + @`inline` private[this] final def computeHash(o: K): Int = { + val h = if(o.asInstanceOf[AnyRef] eq null) 0 else o.hashCode + h ^ (h >>> 16) + } + + @`inline` private[this] final def index(hash: Int) = hash & (table.length - 1) + + override protected def fromSpecific(coll: (IterableOnce[(K, V)]^) @uncheckedVariance): CollisionProofHashMap[K, V] @uncheckedVariance = CollisionProofHashMap.from(coll) + override protected def newSpecificBuilder: Builder[(K, V), CollisionProofHashMap[K, V]] @uncheckedVariance = CollisionProofHashMap.newBuilder[K, V] + + override def empty: CollisionProofHashMap[K, V] = new CollisionProofHashMap[K, V] + + override def contains(key: K): Boolean = findNode(key) ne null + + def get(key: K): Option[V] = findNode(key) match { + case null => None + case nd => Some(nd match { + case nd: LLNode @uc => nd.value + case nd: RBNode @uc => nd.value + }) + } + + @throws[NoSuchElementException] + override def apply(key: K): V = findNode(key) match { + case null => default(key) + case nd => nd match { + case nd: LLNode @uc => nd.value + case nd: RBNode @uc => nd.value + } + } + + override def getOrElse[V1 >: V](key: K, default: => V1): V1 = { + val nd = findNode(key) + if (nd eq null) default else nd match { + case nd: LLNode @uc => nd.value + case n => n.asInstanceOf[RBNode].value + } + } + + @`inline` private[this] def findNode(elem: K): Node = { + val hash = computeHash(elem) + table(index(hash)) match { + case null => null + case n: LLNode @uc => n.getNode(elem, hash) + case n => n.asInstanceOf[RBNode].getNode(elem, hash) + } + } + + override def sizeHint(size: Int): Unit = { + val target = tableSizeFor(((size + 1).toDouble / loadFactor).toInt) + if(target > table.length) { + if(size == 0) reallocTable(target) + else growTable(target) + } + } + + override def update(key: K, value: V): Unit = put0(key, value, false) + + override def put(key: K, value: V): Option[V] = put0(key, value, true) match { + case null => None + case sm => sm + } + + def addOne(elem: (K, V)): this.type = { put0(elem._1, elem._2, false); this } + + @`inline` private[this] def put0(key: K, value: V, getOld: Boolean): Some[V] = { + if(contentSize + 1 >= threshold) growTable(table.length * 2) + val hash = computeHash(key) + val idx = index(hash) + put0(key, value, getOld, hash, idx) + } + + private[this] def put0(key: K, value: V, getOld: Boolean, hash: Int, idx: Int): Some[V] = { + val res = table(idx) match { + case n: RBNode @uc => + insert(n, idx, key, hash, value) + case _old => + val old: LLNode = _old.asInstanceOf[LLNode] + if(old eq null) { + table(idx) = new LLNode(key, hash, value, null) + } else { + var remaining = CollisionProofHashMap.treeifyThreshold + var prev: LLNode = null + var n = old + while((n ne null) && n.hash <= hash && remaining > 0) { + if(n.hash == hash && key == n.key) { + val old = n.value + n.value = value + return (if(getOld) Some(old) else null) + } + prev = n + n = n.next + remaining -= 1 + } + if(remaining == 0) { + treeify(old, idx) + return put0(key, value, getOld, hash, idx) + } + if(prev eq null) table(idx) = new LLNode(key, hash, value, old) + else prev.next = new LLNode(key, hash, value, prev.next) + } + true + } + if(res) contentSize += 1 + if(res) Some(null.asInstanceOf[V]) else null //TODO + } + + private[this] def treeify(old: LLNode, idx: Int): Unit = { + table(idx) = CollisionProofHashMap.leaf(old.key, old.hash, old.value, red = false, null) + var n: LLNode = old.next + while(n ne null) { + val root = table(idx).asInstanceOf[RBNode] + insertIntoExisting(root, idx, n.key, n.hash, n.value, root) + n = n.next + } + } + + override def addAll(xs: IterableOnce[(K, V)]^): this.type = { + val k = xs.knownSize + if(k > 0) sizeHint(contentSize + k) + super.addAll(xs) + } + + // returns the old value or Statics.pfMarker if not found + private[this] def remove0(elem: K) : Any = { + val hash = computeHash(elem) + val idx = index(hash) + table(idx) match { + case null => Statics.pfMarker + case t: RBNode @uc => + val v = delete(t, idx, elem, hash) + if(v.asInstanceOf[AnyRef] ne Statics.pfMarker) contentSize -= 1 + v + case nd: LLNode @uc if nd.hash == hash && nd.key == elem => + // first element matches + table(idx) = nd.next + contentSize -= 1 + nd.value + case nd: LLNode @uc => + // find an element that matches + var prev = nd + var next = nd.next + while((next ne null) && next.hash <= hash) { + if(next.hash == hash && next.key == elem) { + prev.next = next.next + contentSize -= 1 + return next.value + } + prev = next + next = next.next + } + Statics.pfMarker + } + } + + private[this] abstract class MapIterator[R] extends AbstractIterator[R] { + protected[this] def extract(node: LLNode): R + protected[this] def extract(node: RBNode): R + + private[this] var i = 0 + private[this] var node: Node = null + private[this] val len = table.length + + def hasNext: Boolean = { + if(node ne null) true + else { + while(i < len) { + val n = table(i) + i += 1 + n match { + case null => + case n: RBNode @uc => + node = CollisionProofHashMap.minNodeNonNull(n) + return true + case n: LLNode @uc => + node = n + return true + } + } + false + } + } + + def next(): R = + if(!hasNext) Iterator.empty.next() + else node match { + case n: RBNode @uc => + val r = extract(n) + node = CollisionProofHashMap.successor(n ) + r + case n: LLNode @uc => + val r = extract(n) + node = n.next + r + } + } + + override def keysIterator: Iterator[K] = { + if (isEmpty) Iterator.empty + else new MapIterator[K] { + protected[this] def extract(node: LLNode) = node.key + protected[this] def extract(node: RBNode) = node.key + } + } + + override def iterator: Iterator[(K, V)] = { + if (isEmpty) Iterator.empty + else new MapIterator[(K, V)] { + protected[this] def extract(node: LLNode) = (node.key, node.value) + protected[this] def extract(node: RBNode) = (node.key, node.value) + } + } + + private[this] def growTable(newlen: Int) = { + var oldlen = table.length + table = java.util.Arrays.copyOf(table, newlen) + threshold = newThreshold(table.length) + while(oldlen < newlen) { + var i = 0 + while (i < oldlen) { + val old = table(i) + if(old ne null) splitBucket(old, i, i + oldlen, oldlen) + i += 1 + } + oldlen *= 2 + } + } + + @`inline` private[this] def reallocTable(newlen: Int) = { + table = new Array(newlen) + threshold = newThreshold(table.length) + } + + @`inline` private[this] def splitBucket(tree: Node, lowBucket: Int, highBucket: Int, mask: Int): Unit = tree match { + case t: LLNode @uc => splitBucket(t, lowBucket, highBucket, mask) + case t: RBNode @uc => splitBucket(t, lowBucket, highBucket, mask) + } + + private[this] def splitBucket(list: LLNode, lowBucket: Int, highBucket: Int, mask: Int): Unit = { + val preLow: LLNode = new LLNode(null.asInstanceOf[K], 0, null.asInstanceOf[V], null) + val preHigh: LLNode = new LLNode(null.asInstanceOf[K], 0, null.asInstanceOf[V], null) + //preLow.next = null + //preHigh.next = null + var lastLow: LLNode = preLow + var lastHigh: LLNode = preHigh + var n = list + while(n ne null) { + val next = n.next + if((n.hash & mask) == 0) { // keep low + lastLow.next = n + lastLow = n + } else { // move to high + lastHigh.next = n + lastHigh = n + } + n = next + } + lastLow.next = null + if(list ne preLow.next) table(lowBucket) = preLow.next + if(preHigh.next ne null) { + table(highBucket) = preHigh.next + lastHigh.next = null + } + } + + private[this] def splitBucket(tree: RBNode, lowBucket: Int, highBucket: Int, mask: Int): Unit = { + var lowCount, highCount = 0 + tree.foreachNode((n: RBNode) => if((n.hash & mask) != 0) highCount += 1 else lowCount += 1) + if(highCount != 0) { + if(lowCount == 0) { + table(lowBucket) = null + table(highBucket) = tree + } else { + table(lowBucket) = fromNodes(new CollisionProofHashMap.RBNodesIterator(tree).filter(n => (n.hash & mask) == 0), lowCount) + table(highBucket) = fromNodes(new CollisionProofHashMap.RBNodesIterator(tree).filter(n => (n.hash & mask) != 0), highCount) + } + } + } + + private[this] def tableSizeFor(capacity: Int) = + (Integer.highestOneBit((capacity-1).max(4))*2).min(1 << 30) + + private[this] def newThreshold(size: Int) = (size.toDouble * loadFactor).toInt + + override def clear(): Unit = { + java.util.Arrays.fill(table.asInstanceOf[Array[AnyRef]], null) + contentSize = 0 + } + + override def remove(key: K): Option[V] = { + val v = remove0(key) + if(v.asInstanceOf[AnyRef] eq Statics.pfMarker) None else Some(v.asInstanceOf[V]) + } + + def subtractOne(elem: K): this.type = { remove0(elem); this } + + override def knownSize: Int = size + + override def isEmpty: Boolean = size == 0 + + override def foreach[U](f: ((K, V)) => U): Unit = { + val len = table.length + var i = 0 + while(i < len) { + val n = table(i) + if(n ne null) n match { + case n: LLNode @uc => n.foreach(f) + case n: RBNode @uc => n.foreach(f) + } + i += 1 + } + } + + override def foreachEntry[U](f: (K, V) => U): Unit = { + val len = table.length + var i = 0 + while(i < len) { + val n = table(i) + if(n ne null) n match { + case n: LLNode @uc => n.foreachEntry(f) + case n: RBNode @uc => n.foreachEntry(f) + } + i += 1 + } + } + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(new CollisionProofHashMap.DeserializationFactory[K, V](table.length, loadFactor, ordering), this) + + override protected[this] def className = "CollisionProofHashMap" + + override def getOrElseUpdate(key: K, defaultValue: => V): V = { + val hash = computeHash(key) + val idx = index(hash) + table(idx) match { + case null => () + case n: LLNode @uc => + val nd = n.getNode(key, hash) + if(nd != null) return nd.value + case n => + val nd = n.asInstanceOf[RBNode].getNode(key, hash) + if(nd != null) return nd.value + } + val table0 = table + val default = defaultValue + if(contentSize + 1 >= threshold) growTable(table.length * 2) + // Avoid recomputing index if the `defaultValue()` or new element hasn't triggered a table resize. + val newIdx = if (table0 eq table) idx else index(hash) + put0(key, default, false, hash, newIdx) + default + } + + ///////////////////// Overrides code from SortedMapOps + + /** Builds a new `CollisionProofHashMap` by applying a function to all elements of this $coll. + * + * @param f the function to apply to each element. + * @return a new $coll resulting from applying the given function + * `f` to each element of this $coll and collecting the results. + */ + def map[K2, V2](f: ((K, V)) => (K2, V2)) + (implicit @implicitNotFound(CollisionProofHashMap.ordMsg) ordering: Ordering[K2]): CollisionProofHashMap[K2, V2] = + sortedMapFactory.from(new View.Map[(K, V), (K2, V2)](this, f)) + + /** Builds a new `CollisionProofHashMap` by applying a function to all elements of this $coll + * and using the elements of the resulting collections. + * + * @param f the function to apply to each element. + * @return a new $coll resulting from applying the given collection-valued function + * `f` to each element of this $coll and concatenating the results. + */ + def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)]) + (implicit @implicitNotFound(CollisionProofHashMap.ordMsg) ordering: Ordering[K2]): CollisionProofHashMap[K2, V2] = + sortedMapFactory.from(new View.FlatMap(this, f)) + + /** Builds a new sorted map by applying a partial function to all elements of this $coll + * on which the function is defined. + * + * @param pf the partial function which filters and maps the $coll. + * @return a new $coll resulting from applying the given partial function + * `pf` to each element on which it is defined and collecting the results. + * The order of the elements is preserved. + */ + def collect[K2, V2](pf: PartialFunction[(K, V), (K2, V2)]) + (implicit @implicitNotFound(CollisionProofHashMap.ordMsg) ordering: Ordering[K2]): CollisionProofHashMap[K2, V2] = + sortedMapFactory.from(new View.Collect(this, pf)) + + override def concat[V2 >: V](suffix: IterableOnce[(K, V2)]^): CollisionProofHashMap[K, V2] = sortedMapFactory.from(suffix match { + case it: Iterable[(K, V2)] => new View.Concat(this, it) + case _ => iterator.concat(suffix.iterator) + }) + + /** Alias for `concat` */ + @`inline` override final def ++ [V2 >: V](xs: IterableOnce[(K, V2)]^): CollisionProofHashMap[K, V2] = concat(xs) + + @deprecated("Consider requiring an immutable Map or fall back to Map.concat", "2.13.0") + override def + [V1 >: V](kv: (K, V1)): CollisionProofHashMap[K, V1] = + sortedMapFactory.from(new View.Appended(this, kv)) + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + override def + [V1 >: V](elem1: (K, V1), elem2: (K, V1), elems: (K, V1)*): CollisionProofHashMap[K, V1] = + sortedMapFactory.from(new View.Concat(new View.Appended(new View.Appended(this, elem1), elem2), elems)) + + ///////////////////// RedBlackTree code derived from mutable.RedBlackTree: + + @`inline` private[this] def isRed(node: RBNode) = (node ne null) && node.red + @`inline` private[this] def isBlack(node: RBNode) = (node eq null) || !node.red + + @unused @`inline` private[this] def compare(key: K, hash: Int, node: LLNode): Int = { + val i = hash - node.hash + if(i != 0) i else ordering.compare(key, node.key) + } + + @`inline` private[this] def compare(key: K, hash: Int, node: RBNode): Int = { + /*val i = hash - node.hash + if(i != 0) i else*/ ordering.compare(key, node.key) + } + + // ---- insertion ---- + + @tailrec private[this] final def insertIntoExisting(_root: RBNode, bucket: Int, key: K, hash: Int, value: V, x: RBNode): Boolean = { + val cmp = compare(key, hash, x) + if(cmp == 0) { + x.value = value + false + } else { + val next = if(cmp < 0) x.left else x.right + if(next eq null) { + val z = CollisionProofHashMap.leaf(key, hash, value, red = true, x) + if (cmp < 0) x.left = z else x.right = z + table(bucket) = fixAfterInsert(_root, z) + return true + } + else insertIntoExisting(_root, bucket, key, hash, value, next) + } + } + + private[this] final def insert(tree: RBNode, bucket: Int, key: K, hash: Int, value: V): Boolean = { + if(tree eq null) { + table(bucket) = CollisionProofHashMap.leaf(key, hash, value, red = false, null) + true + } else insertIntoExisting(tree, bucket, key, hash, value, tree) + } + + private[this] def fixAfterInsert(_root: RBNode, node: RBNode): RBNode = { + var root = _root + var z = node + while (isRed(z.parent)) { + if (z.parent eq z.parent.parent.left) { + val y = z.parent.parent.right + if (isRed(y)) { + z.parent.red = false + y.red = false + z.parent.parent.red = true + z = z.parent.parent + } else { + if (z eq z.parent.right) { + z = z.parent + root = rotateLeft(root, z) + } + z.parent.red = false + z.parent.parent.red = true + root = rotateRight(root, z.parent.parent) + } + } else { // symmetric cases + val y = z.parent.parent.left + if (isRed(y)) { + z.parent.red = false + y.red = false + z.parent.parent.red = true + z = z.parent.parent + } else { + if (z eq z.parent.left) { + z = z.parent + root = rotateRight(root, z) + } + z.parent.red = false + z.parent.parent.red = true + root = rotateLeft(root, z.parent.parent) + } + } + } + root.red = false + root + } + + // ---- deletion ---- + + // returns the old value or Statics.pfMarker if not found + private[this] def delete(_root: RBNode, bucket: Int, key: K, hash: Int): Any = { + var root = _root + val z = root.getNode(key, hash: Int) + if (z ne null) { + val oldValue = z.value + var y = z + var yIsRed = y.red + var x: RBNode = null + var xParent: RBNode = null + + if (z.left eq null) { + x = z.right + root = transplant(root, z, z.right) + xParent = z.parent + } + else if (z.right eq null) { + x = z.left + root = transplant(root, z, z.left) + xParent = z.parent + } + else { + y = CollisionProofHashMap.minNodeNonNull(z.right) + yIsRed = y.red + x = y.right + + if (y.parent eq z) xParent = y + else { + xParent = y.parent + root = transplant(root, y, y.right) + y.right = z.right + y.right.parent = y + } + root = transplant(root, z, y) + y.left = z.left + y.left.parent = y + y.red = z.red + } + + if (!yIsRed) root = fixAfterDelete(root, x, xParent) + if(root ne _root) table(bucket) = root + oldValue + } else Statics.pfMarker + } + + private[this] def fixAfterDelete(_root: RBNode, node: RBNode, parent: RBNode): RBNode = { + var root = _root + var x = node + var xParent = parent + while ((x ne root) && isBlack(x)) { + if (x eq xParent.left) { + var w = xParent.right + // assert(w ne null) + + if (w.red) { + w.red = false + xParent.red = true + root = rotateLeft(root, xParent) + w = xParent.right + } + if (isBlack(w.left) && isBlack(w.right)) { + w.red = true + x = xParent + } else { + if (isBlack(w.right)) { + w.left.red = false + w.red = true + root = rotateRight(root, w) + w = xParent.right + } + w.red = xParent.red + xParent.red = false + w.right.red = false + root = rotateLeft(root, xParent) + x = root + } + } else { // symmetric cases + var w = xParent.left + // assert(w ne null) + + if (w.red) { + w.red = false + xParent.red = true + root = rotateRight(root, xParent) + w = xParent.left + } + if (isBlack(w.right) && isBlack(w.left)) { + w.red = true + x = xParent + } else { + if (isBlack(w.left)) { + w.right.red = false + w.red = true + root = rotateLeft(root, w) + w = xParent.left + } + w.red = xParent.red + xParent.red = false + w.left.red = false + root = rotateRight(root, xParent) + x = root + } + } + xParent = x.parent + } + if (x ne null) x.red = false + root + } + + // ---- helpers ---- + + @`inline` private[this] def rotateLeft(_root: RBNode, x: RBNode): RBNode = { + var root = _root + val y = x.right + x.right = y.left + + val xp = x.parent + if (y.left ne null) y.left.parent = x + y.parent = xp + + if (xp eq null) root = y + else if (x eq xp.left) xp.left = y + else xp.right = y + + y.left = x + x.parent = y + root + } + + @`inline` private[this] def rotateRight(_root: RBNode, x: RBNode): RBNode = { + var root = _root + val y = x.left + x.left = y.right + + val xp = x.parent + if (y.right ne null) y.right.parent = x + y.parent = xp + + if (xp eq null) root = y + else if (x eq xp.right) xp.right = y + else xp.left = y + + y.right = x + x.parent = y + root + } + + /** + * Transplant the node `from` to the place of node `to`. This is done by setting `from` as a child of `to`'s previous + * parent and setting `from`'s parent to the `to`'s previous parent. The children of `from` are left unchanged. + */ + private[this] def transplant(_root: RBNode, to: RBNode, from: RBNode): RBNode = { + var root = _root + if (to.parent eq null) root = from + else if (to eq to.parent.left) to.parent.left = from + else to.parent.right = from + if (from ne null) from.parent = to.parent + root + } + + // building + + def fromNodes(xs: Iterator[Node], size: Int): RBNode = { + val maxUsedDepth = 32 - Integer.numberOfLeadingZeros(size) // maximum depth of non-leaf nodes + def f(level: Int, size: Int): RBNode = size match { + case 0 => null + case 1 => + val nn = xs.next() + val (key, hash, value) = nn match { + case nn: LLNode @uc => (nn.key, nn.hash, nn.value) + case nn: RBNode @uc => (nn.key, nn.hash, nn.value) + } + new RBNode(key, hash, value, level == maxUsedDepth && level != 1, null, null, null) + case n => + val leftSize = (size-1)/2 + val left = f(level+1, leftSize) + val nn = xs.next() + val right = f(level+1, size-1-leftSize) + val (key, hash, value) = nn match { + case nn: LLNode @uc => (nn.key, nn.hash, nn.value) + case nn: RBNode @uc => (nn.key, nn.hash, nn.value) + } + val n = new RBNode(key, hash, value, false, left, right, null) + if(left ne null) left.parent = n + right.parent = n + n + } + f(1, size) + } +} + +/** + * $factoryInfo + * @define Coll `mutable.CollisionProofHashMap` + * @define coll mutable collision-proof hash map + */ +@SerialVersionUID(3L) +object CollisionProofHashMap extends SortedMapFactory[CollisionProofHashMap] { + private[collection] final val ordMsg = "No implicit Ordering[${K2}] found to build a CollisionProofHashMap[${K2}, ${V2}]. You may want to upcast to a Map[${K}, ${V}] first by calling `unsorted`." + + def from[sealed K : Ordering, sealed V](it: scala.collection.IterableOnce[(K, V)]^): CollisionProofHashMap[K, V] = { + val k = it.knownSize + val cap = if(k > 0) ((k + 1).toDouble / defaultLoadFactor).toInt else defaultInitialCapacity + new CollisionProofHashMap[K, V](cap, defaultLoadFactor) ++= it + } + + def empty[sealed K : Ordering, sealed V]: CollisionProofHashMap[K, V] = new CollisionProofHashMap[K, V] + + def newBuilder[sealed K : Ordering, sealed V]: Builder[(K, V), CollisionProofHashMap[K, V]] = newBuilder(defaultInitialCapacity, defaultLoadFactor) + + def newBuilder[sealed K : Ordering, sealed V](initialCapacity: Int, loadFactor: Double): Builder[(K, V), CollisionProofHashMap[K, V]] = + new GrowableBuilder[(K, V), CollisionProofHashMap[K, V]](new CollisionProofHashMap[K, V](initialCapacity, loadFactor)) { + override def sizeHint(size: Int) = elems.sizeHint(size) + } + + /** The default load factor for the hash table */ + final def defaultLoadFactor: Double = 0.75 + + /** The default initial capacity for the hash table */ + final def defaultInitialCapacity: Int = 16 + + @SerialVersionUID(3L) + private final class DeserializationFactory[sealed K, sealed V](val tableLength: Int, val loadFactor: Double, val ordering: Ordering[K]) extends Factory[(K, V), CollisionProofHashMap[K, V]] with Serializable { + def fromSpecific(it: IterableOnce[(K, V)]^): CollisionProofHashMap[K, V] = new CollisionProofHashMap[K, V](tableLength, loadFactor)(ordering) ++= it + def newBuilder: Builder[(K, V), CollisionProofHashMap[K, V]] = CollisionProofHashMap.newBuilder(tableLength, loadFactor)(ordering) + } + + @unused @`inline` private def compare[K, V](key: K, hash: Int, node: LLNode[K, V])(implicit ord: Ordering[K]): Int = { + val i = hash - node.hash + if(i != 0) i else ord.compare(key, node.key) + } + + @`inline` private def compare[K, V](key: K, hash: Int, node: RBNode[K, V])(implicit ord: Ordering[K]): Int = { + /*val i = hash - node.hash + if(i != 0) i else*/ ord.compare(key, node.key) + } + + private final val treeifyThreshold = 8 + + // Superclass for RBNode and LLNode to help the JIT with optimizing instance checks, but no shared common fields. + // Keeping calls monomorphic where possible and dispatching manually where needed is faster. + sealed abstract class Node + + /////////////////////////// Red-Black Tree Node + + final class RBNode[sealed K, sealed V](var key: K, var hash: Int, var value: V, var red: Boolean, var left: RBNode[K, V], var right: RBNode[K, V], var parent: RBNode[K, V]) extends Node { + override def toString: String = "RBNode(" + key + ", " + hash + ", " + value + ", " + red + ", " + left + ", " + right + ")" + + @tailrec def getNode(k: K, h: Int)(implicit ord: Ordering[K]): RBNode[K, V] = { + val cmp = compare(k, h, this) + if (cmp < 0) { + if(left ne null) left.getNode(k, h) else null + } else if (cmp > 0) { + if(right ne null) right.getNode(k, h) else null + } else this + } + + def foreach[U](f: ((K, V)) => U): Unit = { + if(left ne null) left.foreach(f) + f((key, value)) + if(right ne null) right.foreach(f) + } + + def foreachEntry[U](f: (K, V) => U): Unit = { + if(left ne null) left.foreachEntry(f) + f(key, value) + if(right ne null) right.foreachEntry(f) + } + + def foreachNode[U](f: RBNode[K, V] => U): Unit = { + if(left ne null) left.foreachNode(f) + f(this) + if(right ne null) right.foreachNode(f) + } + } + + @`inline` private def leaf[sealed A, sealed B](key: A, hash: Int, value: B, red: Boolean, parent: RBNode[A, B]): RBNode[A, B] = + new RBNode(key, hash, value, red, null, null, parent) + + @tailrec private def minNodeNonNull[sealed A, sealed B](node: RBNode[A, B]): RBNode[A, B] = + if (node.left eq null) node else minNodeNonNull(node.left) + + /** + * Returns the node that follows `node` in an in-order tree traversal. If `node` has the maximum key (and is, + * therefore, the last node), this method returns `null`. + */ + private def successor[sealed A, sealed B](node: RBNode[A, B]): RBNode[A, B] = { + if (node.right ne null) minNodeNonNull(node.right) + else { + var x = node + var y = x.parent + while ((y ne null) && (x eq y.right)) { + x = y + y = y.parent + } + y + } + } + + private final class RBNodesIterator[sealed A, sealed B](tree: RBNode[A, B])(implicit @unused ord: Ordering[A]) extends AbstractIterator[RBNode[A, B]] { + private[this] var nextNode: RBNode[A, B] = if(tree eq null) null else minNodeNonNull(tree) + + def hasNext: Boolean = nextNode ne null + + @throws[NoSuchElementException] + def next(): RBNode[A, B] = nextNode match { + case null => Iterator.empty.next() + case node => + nextNode = successor(node) + node + } + } + + /////////////////////////// Linked List Node + + private final class LLNode[sealed K, sealed V](var key: K, var hash: Int, var value: V, var next: LLNode[K, V]) extends Node { + override def toString = s"LLNode($key, $value, $hash) -> $next" + + private[this] def eq(a: Any, b: Any): Boolean = + if(a.asInstanceOf[AnyRef] eq null) b.asInstanceOf[AnyRef] eq null else a.asInstanceOf[AnyRef].equals(b) + + @tailrec def getNode(k: K, h: Int)(implicit ord: Ordering[K]): LLNode[K, V] = { + if(h == hash && eq(k, key) /*ord.compare(k, key) == 0*/) this + else if((next eq null) || (hash > h)) null + else next.getNode(k, h) + } + + @tailrec def foreach[U](f: ((K, V)) => U): Unit = { + f((key, value)) + if(next ne null) next.foreach(f) + } + + @tailrec def foreachEntry[U](f: (K, V) => U): Unit = { + f(key, value) + if(next ne null) next.foreachEntry(f) + } + + @tailrec def foreachNode[U](f: LLNode[K, V] => U): Unit = { + f(this) + if(next ne null) next.foreachNode(f) + } + } +} From ffbaf1f23f93663013a5c34d79a61c0f282518ae Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 18:31:56 +0100 Subject: [PATCH 54/89] Avoid infinite recursions when checking F-bounded types --- .../dotty/tools/dotc/cc/CheckCaptures.scala | 32 +++++++++++-------- 1 file changed, 18 insertions(+), 14 deletions(-) diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index 9d56c93bfaf5..ae9a6eaff83e 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -14,7 +14,7 @@ import typer.RefChecks.{checkAllOverrides, checkSelfAgainstParents, OverridingPa import typer.Checking.{checkBounds, checkAppliedTypesIn} import typer.ErrorReporting.{Addenda, err} import typer.ProtoTypes.{AnySelectionProto, LhsProto} -import util.{SimpleIdentitySet, EqHashMap, SrcPos, Property} +import util.{SimpleIdentitySet, EqHashMap, EqHashSet, SrcPos, Property} import transform.SymUtils.* import transform.{Recheck, PreRecheck} import Recheck.* @@ -147,6 +147,8 @@ object CheckCaptures: private def disallowRootCapabilitiesIn(tp: Type, carrier: Symbol, what: String, have: String, addendum: String, pos: SrcPos)(using Context) = val check = new TypeTraverser: + private val seen = new EqHashSet[TypeRef] + extension (tparam: Symbol) def isParametricIn(carrier: Symbol): Boolean = val encl = carrier.maybeOwner.enclosingMethodOrClass if encl.isClass then tparam.isParametricIn(encl) @@ -160,19 +162,21 @@ object CheckCaptures: def traverse(t: Type) = t.dealiasKeepAnnots match case t: TypeRef => - capt.println(i"disallow $t, $tp, $what, ${t.isSealed}") - t.info match - case TypeBounds(_, hi) if !t.isSealed && !t.symbol.isParametricIn(carrier) => - if hi.isAny then - report.error( - em"""$what cannot $have $tp since - |that type refers to the type variable $t, which is not sealed. - |$addendum""", - pos) - else - traverse(hi) - case _ => - traverseChildren(t) + if !seen.contains(t) then + capt.println(i"disallow $t, $tp, $what, ${t.isSealed}") + seen += t + t.info match + case TypeBounds(_, hi) if !t.isSealed && !t.symbol.isParametricIn(carrier) => + if hi.isAny then + report.error( + em"""$what cannot $have $tp since + |that type refers to the type variable $t, which is not sealed. + |$addendum""", + pos) + else + traverse(hi) + case _ => + traverseChildren(t) case AnnotatedType(_, ann) if ann.symbol == defn.UncheckedCapturesAnnot => () case t => From 7304ba60d1eed5ac53e0da741916d5c11bbaae58 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 18:32:10 +0100 Subject: [PATCH 55/89] Add HashTable.scala to stdlib --- .../stdlib/collection/mutable/HashTable.scala | 418 ++++++++++++++++++ 1 file changed, 418 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/HashTable.scala diff --git a/tests/pos-special/stdlib/collection/mutable/HashTable.scala b/tests/pos-special/stdlib/collection/mutable/HashTable.scala new file mode 100644 index 000000000000..a3534e322cf3 --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/HashTable.scala @@ -0,0 +1,418 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.mutable + +import collection.{AbstractIterator, Iterator} + +import java.lang.Integer.{numberOfLeadingZeros, rotateRight} +import scala.util.hashing.byteswap32 + +import java.lang.Integer +import language.experimental.captureChecking + +/** This class can be used to construct data structures that are based + * on hashtables. Class `HashTable[A]` implements a hashtable + * that maps keys of type `A` to values of the fully abstract + * member type `Entry`. Classes that make use of `HashTable` + * have to provide an implementation for `Entry`. + * + * There are mainly two parameters that affect the performance of a hashtable: + * the initial size and the load factor. The size + * refers to the number of buckets in the hashtable, and the load + * factor is a measure of how full the hashtable is allowed to get before + * its size is automatically doubled. Both parameters may be changed by + * overriding the corresponding values in class `HashTable`. + * + * @tparam A type of the elements contained in this hash table. + */ +// Not used in the standard library, but used in scala-parallel-collections +private[collection] trait HashTable[sealed A, B, Entry >: Null <: HashEntry[A, Entry]] extends HashTable.HashUtils[A] { + // Replacing Entry type parameter by abstract type member here allows to not expose to public + // implementation-specific entry classes such as `DefaultEntry` or `LinkedEntry`. + // However, I'm afraid it's too late now for such breaking change. + import HashTable._ + + protected var _loadFactor = defaultLoadFactor + + /** The actual hash table. + */ + protected[collection] var table: Array[HashEntry[A, Entry]] = new Array(initialCapacity) + + /** The number of mappings contained in this hash table. + */ + protected[collection] var tableSize: Int = 0 + + final def size: Int = tableSize + + /** The next size value at which to resize (capacity * load factor). + */ + protected[collection] var threshold: Int = initialThreshold(_loadFactor) + + /** The array keeping track of the number of elements in 32 element blocks. + */ + protected var sizemap: Array[Int] = null + + protected var seedvalue: Int = tableSizeSeed + + protected def tableSizeSeed = Integer.bitCount(table.length - 1) + + /** The initial size of the hash table. + */ + protected def initialSize: Int = 16 + + /** The initial threshold. + */ + private def initialThreshold(_loadFactor: Int): Int = newThreshold(_loadFactor, initialCapacity) + + private def initialCapacity = capacity(initialSize) + + private def lastPopulatedIndex = { + var idx = table.length - 1 + while (table(idx) == null && idx > 0) + idx -= 1 + + idx + } + + /** + * Initializes the collection from the input stream. `readEntry` will be called for each + * entry to be read from the input stream. + */ + private[collection] def init(in: java.io.ObjectInputStream, readEntry: => Entry): Unit = { + _loadFactor = in.readInt() + assert(_loadFactor > 0) + + val size = in.readInt() + tableSize = 0 + assert(size >= 0) + + seedvalue = in.readInt() + + val smDefined = in.readBoolean() + + table = new Array(capacity(sizeForThreshold(_loadFactor, size))) + threshold = newThreshold(_loadFactor, table.length) + + if (smDefined) sizeMapInit(table.length) else sizemap = null + + var index = 0 + while (index < size) { + addEntry(readEntry) + index += 1 + } + } + + /** + * Serializes the collection to the output stream by saving the load factor, collection + * size and collection entries. `writeEntry` is responsible for writing an entry to the stream. + * + * `foreachEntry` determines the order in which the key/value pairs are saved to the stream. To + * deserialize, `init` should be used. + */ + private[collection] def serializeTo(out: java.io.ObjectOutputStream, writeEntry: Entry => Unit): Unit = { + out.writeInt(_loadFactor) + out.writeInt(tableSize) + out.writeInt(seedvalue) + out.writeBoolean(isSizeMapDefined) + + foreachEntry(writeEntry) + } + + /** Find entry with given key in table, null if not found. + */ + final def findEntry(key: A): Entry = + findEntry0(key, index(elemHashCode(key))) + + protected[collection] final def findEntry0(key: A, h: Int): Entry = { + var e = table(h).asInstanceOf[Entry] + while (e != null && !elemEquals(e.key, key)) e = e.next + e + } + + /** Add entry to table + * pre: no entry with same key exists + */ + protected[collection] final def addEntry(e: Entry): Unit = { + addEntry0(e, index(elemHashCode(e.key))) + } + + protected[collection] final def addEntry0(e: Entry, h: Int): Unit = { + e.next = table(h).asInstanceOf[Entry] + table(h) = e + tableSize = tableSize + 1 + nnSizeMapAdd(h) + if (tableSize > threshold) + resize(2 * table.length) + } + + /** Find entry with given key in table, or add new one if not found. + * May be somewhat faster then `findEntry`/`addEntry` pair as it + * computes entry's hash index only once. + * Returns entry found in table or null. + * New entries are created by calling `createNewEntry` method. + */ + def findOrAddEntry(key: A, value: B): Entry = { + val h = index(elemHashCode(key)) + val e = findEntry0(key, h) + if (e ne null) e else { addEntry0(createNewEntry(key, value), h); null } + } + + /** Creates new entry to be immediately inserted into the hashtable. + * This method is guaranteed to be called only once and in case that the entry + * will be added. In other words, an implementation may be side-effecting. + */ + def createNewEntry(key: A, value: B): Entry + + /** Remove entry from table if present. + */ + final def removeEntry(key: A) : Entry = { + removeEntry0(key, index(elemHashCode(key))) + } + /** Remove entry from table if present. + */ + private[collection] final def removeEntry0(key: A, h: Int) : Entry = { + var e = table(h).asInstanceOf[Entry] + if (e != null) { + if (elemEquals(e.key, key)) { + table(h) = e.next + tableSize = tableSize - 1 + nnSizeMapRemove(h) + e.next = null + return e + } else { + var e1 = e.next + while (e1 != null && !elemEquals(e1.key, key)) { + e = e1 + e1 = e1.next + } + if (e1 != null) { + e.next = e1.next + tableSize = tableSize - 1 + nnSizeMapRemove(h) + e1.next = null + return e1 + } + } + } + null + } + + /** An iterator returning all entries. + */ + def entriesIterator: Iterator[Entry] = new AbstractIterator[Entry] { + val iterTable = table + var idx = lastPopulatedIndex + var es = iterTable(idx) + + def hasNext = es != null + def next() = { + val res = es + es = es.next + while (es == null && idx > 0) { + idx = idx - 1 + es = iterTable(idx) + } + res.asInstanceOf[Entry] + } + } + + /** Avoid iterator for a 2x faster traversal. */ + def foreachEntry[U](f: Entry => U): Unit = { + val iterTable = table + var idx = lastPopulatedIndex + var es = iterTable(idx) + + while (es != null) { + val next = es.next // Cache next in case f removes es. + f(es.asInstanceOf[Entry]) + es = next + + while (es == null && idx > 0) { + idx -= 1 + es = iterTable(idx) + } + } + } + + /** Remove all entries from table + */ + def clearTable(): Unit = { + var i = table.length - 1 + while (i >= 0) { table(i) = null; i = i - 1 } + tableSize = 0 + nnSizeMapReset(0) + } + + private def resize(newSize: Int): Unit = { + val oldTable = table + table = new Array(newSize) + nnSizeMapReset(table.length) + var i = oldTable.length - 1 + while (i >= 0) { + var e = oldTable(i) + while (e != null) { + val h = index(elemHashCode(e.key)) + val e1 = e.next + e.next = table(h).asInstanceOf[Entry] + table(h) = e + e = e1 + nnSizeMapAdd(h) + } + i = i - 1 + } + threshold = newThreshold(_loadFactor, newSize) + } + + /* Size map handling code */ + + /* + * The following three sizeMap* functions (Add, Remove, Reset) + * are used to update the size map of the hash table. + * + * The size map logically divides the hash table into `sizeMapBucketSize` element buckets + * by keeping an integer entry for each such bucket. Each integer entry simply denotes + * the number of elements in the corresponding bucket. + * Best understood through an example, see: + * table = [/, 1, /, 6, 90, /, -3, 5] (8 entries) + * sizemap = [ 2 | 3 ] (2 entries) + * where sizeMapBucketSize == 4. + * + * By default the size map is not initialized, so these methods don't do anything, thus, + * their impact on hash table performance is negligible. However, if the hash table + * is converted into a parallel hash table, the size map is initialized, as it will be needed + * there. + */ + protected final def nnSizeMapAdd(h: Int) = if (sizemap ne null) { + sizemap(h >> sizeMapBucketBitSize) += 1 + } + + protected final def nnSizeMapRemove(h: Int) = if (sizemap ne null) { + sizemap(h >> sizeMapBucketBitSize) -= 1 + } + + protected final def nnSizeMapReset(tableLength: Int) = if (sizemap ne null) { + val nsize = calcSizeMapSize(tableLength) + if (sizemap.length != nsize) sizemap = new Array[Int](nsize) + else java.util.Arrays.fill(sizemap, 0) + } + + private[collection] final def totalSizeMapBuckets = if (sizeMapBucketSize < table.length) 1 else table.length / sizeMapBucketSize + + protected final def calcSizeMapSize(tableLength: Int) = (tableLength >> sizeMapBucketBitSize) + 1 + + // discards the previous sizemap and only allocates a new one + protected def sizeMapInit(tableLength: Int): Unit = { + sizemap = new Array[Int](calcSizeMapSize(tableLength)) + } + + // discards the previous sizemap and populates the new one + protected final def sizeMapInitAndRebuild() = { + sizeMapInit(table.length) + + // go through the buckets, count elements + var tableidx = 0 + var bucketidx = 0 + val tbl = table + var tableuntil = 0 + if (tbl.length < sizeMapBucketSize) tableuntil = tbl.length else tableuntil = sizeMapBucketSize + val totalbuckets = totalSizeMapBuckets + while (bucketidx < totalbuckets) { + var currbucketsize = 0 + while (tableidx < tableuntil) { + var e = tbl(tableidx) + while (e ne null) { + currbucketsize += 1 + e = e.next + } + tableidx += 1 + } + sizemap(bucketidx) = currbucketsize + tableuntil += sizeMapBucketSize + bucketidx += 1 + } + } + + private[collection] def printSizeMap() = { + println(sizemap.to(collection.immutable.List)) + } + + protected final def sizeMapDisable() = sizemap = null + + protected final def isSizeMapDefined = sizemap ne null + + // override to automatically initialize the size map + protected def alwaysInitSizeMap = false + + /* End of size map handling code */ + + protected def elemEquals(key1: A, key2: A): Boolean = (key1 == key2) + + /** + * Note: we take the most significant bits of the hashcode, not the lower ones + * this is of crucial importance when populating the table in parallel + */ + protected[collection] final def index(hcode: Int): Int = { + val ones = table.length - 1 + val exponent = Integer.numberOfLeadingZeros(ones) + (improve(hcode, seedvalue) >>> exponent) & ones + } +} + +private[collection] object HashTable { + /** The load factor for the hash table (in 0.001 step). + */ + private[collection] final def defaultLoadFactor: Int = 750 // corresponds to 75% + private[collection] final def loadFactorDenum = 1000 // should be loadFactorDenom, but changing that isn't binary compatible + + private[collection] final def newThreshold(_loadFactor: Int, size: Int) = ((size.toLong * _loadFactor) / loadFactorDenum).toInt + + private[collection] final def sizeForThreshold(_loadFactor: Int, thr: Int) = ((thr.toLong * loadFactorDenum) / _loadFactor).toInt + + private[collection] final def capacity(expectedSize: Int) = nextPositivePowerOfTwo(expectedSize) + + trait HashUtils[KeyType] { + protected final def sizeMapBucketBitSize = 5 + // so that: + protected final def sizeMapBucketSize = 1 << sizeMapBucketBitSize + + protected[collection] def elemHashCode(key: KeyType) = key.## + + /** + * Defer to a high-quality hash in [[scala.util.hashing]]. + * The goal is to distribute across bins as well as possible even if a hash code has low entropy at some bits. + *

+ * OLD VERSION - quick, but bad for sequence 0-10000 - little entropy in higher bits - since 2003 + * {{{ + * var h: Int = hcode + ~(hcode << 9) + * h = h ^ (h >>> 14) + * h = h + (h << 4) + * h ^ (h >>> 10) + * }}} + * the rest of the computation is due to SI-5293 + */ + protected final def improve(hcode: Int, seed: Int): Int = rotateRight(byteswap32(hcode), seed) + } + + /** + * Returns a power of two >= `target`. + */ + private[collection] def nextPositivePowerOfTwo(target: Int): Int = 1 << -numberOfLeadingZeros(target - 1) +} + +/** Class used internally. + */ +private[collection] trait HashEntry[A, sealed E <: HashEntry[A, E]] { + val key: A + var next: E = _ +} From f3ed83b748a849b371659b84c884a739acbead81 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 18:38:51 +0100 Subject: [PATCH 56/89] Add HashSet to stdlib --- .../stdlib/collection/Iterator.scala | 2 +- .../collection/StrictOptimizedSeqOps.scala | 2 +- .../stdlib/collection/mutable/HashSet.scala | 457 ++++++++++++++++++ .../stdlib/collection/mutable/MultiMap.scala | 2 +- 4 files changed, 460 insertions(+), 3 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/mutable/HashSet.scala diff --git a/tests/pos-special/stdlib/collection/Iterator.scala b/tests/pos-special/stdlib/collection/Iterator.scala index 172cd7c2a282..cf722235008c 100644 --- a/tests/pos-special/stdlib/collection/Iterator.scala +++ b/tests/pos-special/stdlib/collection/Iterator.scala @@ -562,7 +562,7 @@ trait Iterator[+A] extends IterableOnce[A] with IterableOnceOps[A, Iterator, Ite */ def distinctBy[B](f: A -> B): Iterator[A]^{this} = new AbstractIterator[A] { - private[this] val traversedValues = mutable.HashSet.empty[B] + private[this] val traversedValues = mutable.HashSet.empty[B @uncheckedCaptures] private[this] var nextElementDefined: Boolean = false private[this] var nextElement: A = _ diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala index 14dea1694d09..7a5c58bf2abf 100644 --- a/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala +++ b/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala @@ -25,7 +25,7 @@ trait StrictOptimizedSeqOps [+A, +CC[_], +C] override def distinctBy[B](f: A -> B): C = { val builder = newSpecificBuilder - val seen = mutable.HashSet.empty[B] + val seen = mutable.HashSet.empty[B @uncheckedCaptures] val it = this.iterator while (it.hasNext) { val next = it.next() diff --git a/tests/pos-special/stdlib/collection/mutable/HashSet.scala b/tests/pos-special/stdlib/collection/mutable/HashSet.scala new file mode 100644 index 000000000000..e8c055ff15ef --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/HashSet.scala @@ -0,0 +1,457 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import scala.annotation.tailrec +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializationProxy +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking + +/** This class implements mutable sets using a hashtable. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-mutable-collection-classes.html#hash-tables "Scala's Collection Library overview"]] + * section on `Hash Tables` for more information. + * + * @define Coll `mutable.HashSet` + * @define coll mutable hash set + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +final class HashSet[sealed A](initialCapacity: Int, loadFactor: Double) + extends AbstractSet[A] + with SetOps[A, HashSet, HashSet[A]] + with StrictOptimizedIterableOps[A, HashSet, HashSet[A]] + with IterableFactoryDefaults[A, HashSet] + with Serializable { + + def this() = this(HashSet.defaultInitialCapacity, HashSet.defaultLoadFactor) + + import HashSet.Node + + /* The Hashset class holds the following invariant: + * - For each i between 0 and table.length, the bucket at table(i) only contains elements whose hash-index is i. + * - Every bucket is sorted in ascendent hash order + * - The sum of the lengths of all buckets is equal to contentSize. + */ + /** The actual hash table. */ + private[this] var table = new Array[Node[A]](tableSizeFor(initialCapacity)) + + /** The next size value at which to resize (capacity * load factor). */ + private[this] var threshold: Int = newThreshold(table.length) + + private[this] var contentSize = 0 + + override def size: Int = contentSize + + /** Performs the inverse operation of improveHash. In this case, it happens to be identical to improveHash*/ + @`inline` private[collection] def unimproveHash(improvedHash: Int): Int = improveHash(improvedHash) + + /** Computes the improved hash of an original (`any.##`) hash. */ + private[this] def improveHash(originalHash: Int): Int = { + // Improve the hash by xoring the high 16 bits into the low 16 bits just in case entropy is skewed towards the + // high-value bits. We only use the lowest bits to determine the hash bucket. This is the same improvement + // algorithm as in java.util.HashMap. + originalHash ^ (originalHash >>> 16) + } + + /** Computes the improved hash of this element */ + @`inline` private[this] def computeHash(o: A): Int = improveHash(o.##) + + @`inline` private[this] def index(hash: Int) = hash & (table.length - 1) + + override def contains(elem: A): Boolean = findNode(elem) ne null + + @`inline` private[this] def findNode(elem: A): Node[A] = { + val hash = computeHash(elem) + table(index(hash)) match { + case null => null + case nd => nd.findNode(elem, hash) + } + } + + override def sizeHint(size: Int): Unit = { + val target = tableSizeFor(((size + 1).toDouble / loadFactor).toInt) + if(target > table.length) growTable(target) + } + + override def add(elem: A) : Boolean = { + if(contentSize + 1 >= threshold) growTable(table.length * 2) + addElem(elem, computeHash(elem)) + } + + override def addAll(xs: IterableOnce[A]^): this.type = { + sizeHint(xs.knownSize) + xs match { + case hs: immutable.HashSet[A] => + hs.foreachWithHash((k, h) => addElem(k, improveHash(h))) + this + case hs: mutable.HashSet[A] => + val iter = hs.nodeIterator + while (iter.hasNext) { + val next = iter.next() + addElem(next.key, next.hash) + } + this + case lhs: mutable.LinkedHashSet[A] => + val iter = lhs.entryIterator + while (iter.hasNext) { + val next = iter.next() + addElem(next.key, next.hash) + } + this + case _ => super.addAll(xs) + } + } + + override def subtractAll(xs: IterableOnce[A]^): this.type = { + if (size == 0) { + return this + } + + xs match { + case hs: immutable.HashSet[A] => + hs.foreachWithHashWhile { (k, h) => + remove(k, improveHash(h)) + size > 0 + } + this + case hs: mutable.HashSet[A] => + val iter = hs.nodeIterator + while (iter.hasNext) { + val next = iter.next() + remove(next.key, next.hash) + if (size == 0) return this + } + this + case lhs: mutable.LinkedHashSet[A] => + val iter = lhs.entryIterator + while (iter.hasNext) { + val next = iter.next() + remove(next.key, next.hash) + if (size == 0) return this + } + this + case _ => super.subtractAll(xs) + } + } + + /** Adds an element to this set + * @param elem element to add + * @param hash the **improved** hash of `elem` (see computeHash) + */ + private[this] def addElem(elem: A, hash: Int) : Boolean = { + val idx = index(hash) + table(idx) match { + case null => + table(idx) = new Node(elem, hash, null) + case old => + var prev: Node[A] = null + var n = old + while((n ne null) && n.hash <= hash) { + if(n.hash == hash && elem == n.key) return false + prev = n + n = n.next + } + if(prev eq null) + table(idx) = new Node(elem, hash, old) + else + prev.next = new Node(elem, hash, prev.next) + } + contentSize += 1 + true + } + + private[this] def remove(elem: A, hash: Int): Boolean = { + val idx = index(hash) + table(idx) match { + case null => false + case nd if nd.hash == hash && nd.key == elem => + // first element matches + table(idx) = nd.next + contentSize -= 1 + true + case nd => + // find an element that matches + var prev = nd + var next = nd.next + while((next ne null) && next.hash <= hash) { + if(next.hash == hash && next.key == elem) { + prev.next = next.next + contentSize -= 1 + return true + } + prev = next + next = next.next + } + false + } + } + + override def remove(elem: A) : Boolean = remove(elem, computeHash(elem)) + + private[this] abstract class HashSetIterator[B] extends AbstractIterator[B] { + private[this] var i = 0 + private[this] var node: Node[A] = null + private[this] val len = table.length + + protected[this] def extract(nd: Node[A]): B + + def hasNext: Boolean = { + if(node ne null) true + else { + while(i < len) { + val n = table(i) + i += 1 + if(n ne null) { node = n; return true } + } + false + } + } + + def next(): B = + if(!hasNext) Iterator.empty.next() + else { + val r = extract(node) + node = node.next + r + } + } + + override def iterator: Iterator[A] = new HashSetIterator[A] { + override protected[this] def extract(nd: Node[A]): A = nd.key + } + + /** Returns an iterator over the nodes stored in this HashSet */ + private[collection] def nodeIterator: Iterator[Node[A]] = new HashSetIterator[Node[A]] { + override protected[this] def extract(nd: Node[A]): Node[A] = nd + } + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + import convert.impl._ + val s = shape.shape match { + case StepperShape.IntShape => new IntTableStepper[Node[A]] (size, table, _.next, _.key.asInstanceOf[Int], 0, table.length) + case StepperShape.LongShape => new LongTableStepper[Node[A]] (size, table, _.next, _.key.asInstanceOf[Long], 0, table.length) + case StepperShape.DoubleShape => new DoubleTableStepper[Node[A]](size, table, _.next, _.key.asInstanceOf[Double], 0, table.length) + case _ => shape.parUnbox(new AnyTableStepper[A, Node[A]](size, table, _.next, _.key, 0, table.length)) + } + s.asInstanceOf[S with EfficientSplit] + } + + private[this] def growTable(newlen: Int) = { + var oldlen = table.length + threshold = newThreshold(newlen) + if(size == 0) table = new Array(newlen) + else { + table = java.util.Arrays.copyOf(table, newlen) + val preLow: Node[A] = new Node(null.asInstanceOf[A], 0, null) + val preHigh: Node[A] = new Node(null.asInstanceOf[A], 0, null) + // Split buckets until the new length has been reached. This could be done more + // efficiently when growing an already filled table to more than double the size. + while(oldlen < newlen) { + var i = 0 + while (i < oldlen) { + val old = table(i) + if(old ne null) { + preLow.next = null + preHigh.next = null + var lastLow: Node[A] = preLow + var lastHigh: Node[A] = preHigh + var n = old + while(n ne null) { + val next = n.next + if((n.hash & oldlen) == 0) { // keep low + lastLow.next = n + lastLow = n + } else { // move to high + lastHigh.next = n + lastHigh = n + } + n = next + } + lastLow.next = null + if(old ne preLow.next) table(i) = preLow.next + if(preHigh.next ne null) { + table(i + oldlen) = preHigh.next + lastHigh.next = null + } + } + i += 1 + } + oldlen *= 2 + } + } + } + + override def filterInPlace(p: A => Boolean): this.type = { + if (nonEmpty) { + var bucket = 0 + + while (bucket < table.length) { + var head = table(bucket) + + while ((head ne null) && !p(head.key)) { + head = head.next + contentSize -= 1 + } + + if (head ne null) { + var prev = head + var next = head.next + + while (next ne null) { + if (p(next.key)) { + prev = next + } else { + prev.next = next.next + contentSize -= 1 + } + next = next.next + } + } + + table(bucket) = head + bucket += 1 + } + } + this + } + + /* + private[mutable] def checkTable(): Unit = { + var i = 0 + var count = 0 + var prev: Node[A] = null + while(i < table.length) { + var n = table(i) + prev = null + while(n != null) { + count += 1 + assert(index(n.hash) == i) + if(prev ne null) assert(prev.hash <= n.hash) + prev = n + n = n.next + } + i += 1 + } + assert(contentSize == count) + } + */ + + private[this] def tableSizeFor(capacity: Int) = + (Integer.highestOneBit((capacity-1).max(4))*2).min(1 << 30) + + private[this] def newThreshold(size: Int) = (size.toDouble * loadFactor).toInt + + def clear(): Unit = { + java.util.Arrays.fill(table.asInstanceOf[Array[AnyRef]], null) + contentSize = 0 + } + + override def iterableFactory: IterableFactory[HashSet] = HashSet + + @`inline` def addOne(elem: A): this.type = { add(elem); this } + + @`inline` def subtractOne(elem: A): this.type = { remove(elem); this } + + override def knownSize: Int = size + + override def isEmpty: Boolean = size == 0 + + override def foreach[U](f: A => U): Unit = { + val len = table.length + var i = 0 + while(i < len) { + val n = table(i) + if(n ne null) n.foreach(f) + i += 1 + } + } + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(new HashSet.DeserializationFactory[A](table.length, loadFactor), this) + + override protected[this] def className = "HashSet" + + override def hashCode: Int = { + val setIterator = this.iterator + val hashIterator: Iterator[Any] = + if (setIterator.isEmpty) setIterator + else new HashSetIterator[Any] { + var hash: Int = 0 + override def hashCode: Int = hash + override protected[this] def extract(nd: Node[A]): Any = { + hash = unimproveHash(nd.hash) + this + } + } + MurmurHash3.unorderedHash(hashIterator, MurmurHash3.setSeed) + } +} + +/** + * $factoryInfo + * @define Coll `mutable.HashSet` + * @define coll mutable hash set + */ +@SerialVersionUID(3L) +object HashSet extends IterableFactory[HashSet] { + + def from[sealed B](it: scala.collection.IterableOnce[B]^): HashSet[B] = { + val k = it.knownSize + val cap = if(k > 0) ((k + 1).toDouble / defaultLoadFactor).toInt else defaultInitialCapacity + new HashSet[B](cap, defaultLoadFactor) ++= it + } + + def empty[sealed A]: HashSet[A] = new HashSet[A] + + def newBuilder[sealed A]: Builder[A, HashSet[A]] = newBuilder(defaultInitialCapacity, defaultLoadFactor) + + def newBuilder[sealed A](initialCapacity: Int, loadFactor: Double): Builder[A, HashSet[A]] = + new GrowableBuilder[A, HashSet[A]](new HashSet[A](initialCapacity, loadFactor)) { + override def sizeHint(size: Int) = elems.sizeHint(size) + } + + /** The default load factor for the hash table */ + final def defaultLoadFactor: Double = 0.75 + + /** The default initial capacity for the hash table */ + final def defaultInitialCapacity: Int = 16 + + @SerialVersionUID(3L) + private final class DeserializationFactory[sealed A](val tableLength: Int, val loadFactor: Double) extends Factory[A, HashSet[A]] with Serializable { + def fromSpecific(it: IterableOnce[A]^): HashSet[A] = new HashSet[A](tableLength, loadFactor) ++= it + def newBuilder: Builder[A, HashSet[A]] = HashSet.newBuilder(tableLength, loadFactor) + } + + private[collection] final class Node[K](_key: K, _hash: Int, private[this] var _next: Node[K]) { + def key: K = _key + def hash: Int = _hash + def next: Node[K] = _next + def next_= (n: Node[K]): Unit = _next = n + + @tailrec + def findNode(k: K, h: Int): Node[K] = + if(h == _hash && k == _key) this + else if((_next eq null) || (_hash > h)) null + else _next.findNode(k, h) + + @tailrec + def foreach[U](f: K => U): Unit = { + f(_key) + if(_next ne null) _next.foreach(f) + } + + override def toString = s"Node($key, $hash) -> $next" + } +} diff --git a/tests/pos-special/stdlib/collection/mutable/MultiMap.scala b/tests/pos-special/stdlib/collection/mutable/MultiMap.scala index 0b250a5548ef..281631c92298 100644 --- a/tests/pos-special/stdlib/collection/mutable/MultiMap.scala +++ b/tests/pos-special/stdlib/collection/mutable/MultiMap.scala @@ -52,7 +52,7 @@ import language.experimental.captureChecking * @define Coll `MultiMap` */ @deprecated("Use a scala.collection.mutable.MultiDict in the scala-collection-contrib module", "2.13.0") -trait MultiMap[K, V] extends Map[K, Set[V]] { +trait MultiMap[K, sealed V] extends Map[K, Set[V]] { /** Creates a new set. * * Classes that use this trait as a mixin can override this method From 7d2f133e56af2d59df684ea467df53b7ca6ed8f5 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 18:42:26 +0100 Subject: [PATCH 57/89] Add OpenHashMap to stdlib --- .../collection/mutable/OpenHashMap.scala | 307 ++++++++++++++++++ 1 file changed, 307 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/mutable/OpenHashMap.scala diff --git a/tests/pos-special/stdlib/collection/mutable/OpenHashMap.scala b/tests/pos-special/stdlib/collection/mutable/OpenHashMap.scala new file mode 100644 index 000000000000..f1deb25b6a8a --- /dev/null +++ b/tests/pos-special/stdlib/collection/mutable/OpenHashMap.scala @@ -0,0 +1,307 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package mutable + +import java.lang.Integer.numberOfLeadingZeros +import java.util.ConcurrentModificationException +import scala.collection.generic.DefaultSerializable +import language.experimental.captureChecking + +/** + * @define Coll `OpenHashMap` + * @define coll open hash map + */ +@deprecated("Use HashMap or one of the specialized versions (LongMap, AnyRefMap) instead of OpenHashMap", "2.13.0") +@SerialVersionUID(3L) +object OpenHashMap extends MapFactory[OpenHashMap] { + + def empty[sealed K, sealed V] = new OpenHashMap[K, V] + def from[sealed K, sealed V](it: IterableOnce[(K, V)]^): OpenHashMap[K,V] = empty ++= it + + def newBuilder[sealed K, sealed V]: Builder[(K, V), OpenHashMap[K,V]] = + new GrowableBuilder[(K, V), OpenHashMap[K, V]](empty) + + /** A hash table entry. + * + * The entry is occupied if and only if its `value` is a `Some`; + * deleted if and only if its `value` is `None`. + * If its `key` is not the default value of type `Key`, the entry is occupied. + * If the entry is occupied, `hash` contains the hash value of `key`. + */ + final private class OpenEntry[sealed Key, sealed Value](var key: Key, + var hash: Int, + var value: Option[Value]) + + private[mutable] def nextPositivePowerOfTwo(target: Int): Int = 1 << -numberOfLeadingZeros(target - 1) +} + +/** A mutable hash map based on an open addressing method. The precise scheme is + * undefined, but it should make a reasonable effort to ensure that an insert + * with consecutive hash codes is not unnecessarily penalised. In particular, + * mappings of consecutive integer keys should work without significant + * performance loss. + * + * @tparam Key type of the keys in this map. + * @tparam Value type of the values in this map. + * @param initialSize the initial size of the internal hash table. + * + * @define Coll `OpenHashMap` + * @define coll open hash map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@deprecated("Use HashMap or one of the specialized versions (LongMap, AnyRefMap) instead of OpenHashMap", "2.13.0") +class OpenHashMap[sealed Key, sealed Value](initialSize : Int) + extends AbstractMap[Key, Value] + with MapOps[Key, Value, OpenHashMap, OpenHashMap[Key, Value]] + with StrictOptimizedIterableOps[(Key, Value), Iterable, OpenHashMap[Key, Value]] + with MapFactoryDefaults[Key, Value, OpenHashMap, Iterable] + with DefaultSerializable { + + import OpenHashMap.OpenEntry + private type Entry = OpenEntry[Key, Value] + + /** A default constructor creates a hashmap with initial size `8`. + */ + def this() = this(8) + + override def mapFactory: MapFactory[OpenHashMap] = OpenHashMap + + private[this] val actualInitialSize = OpenHashMap.nextPositivePowerOfTwo(initialSize) + + private[this] var mask = actualInitialSize - 1 + + /** The hash table. + * + * The table's entries are initialized to `null`, indication of an empty slot. + * A slot is either deleted or occupied if and only if the entry is non-`null`. + */ + private[this] var table = new Array[Entry](actualInitialSize) + + private[this] var _size = 0 + private[this] var deleted = 0 + + // Used for tracking inserts so that iterators can determine if concurrent modification has occurred. + private[this] var modCount = 0 + + override def size = _size + override def knownSize: Int = size + private[this] def size_=(s : Int): Unit = _size = s + override def isEmpty: Boolean = _size == 0 + /** Returns a mangled hash code of the provided key. */ + protected def hashOf(key: Key) = { + var h = key.## + h ^= ((h >>> 20) ^ (h >>> 12)) + h ^ (h >>> 7) ^ (h >>> 4) + } + + /** Increase the size of the table. + * Copy only the occupied slots, effectively eliminating the deleted slots. + */ + private[this] def growTable() = { + val oldSize = mask + 1 + val newSize = 4 * oldSize + val oldTable = table + table = new Array[Entry](newSize) + mask = newSize - 1 + oldTable.foreach( entry => + if (entry != null && entry.value != None) + table(findIndex(entry.key, entry.hash)) = entry ) + deleted = 0 + } + + /** Return the index of the first slot in the hash table (in probe order) + * that is, in order of preference, either occupied by the given key, deleted, or empty. + * + * @param hash hash value for `key` + */ + private[this] def findIndex(key: Key, hash: Int): Int = { + var index = hash & mask + var j = 0 + + // Index of the first slot containing a deleted entry, or -1 if none found yet + var firstDeletedIndex = -1 + + var entry = table(index) + while (entry != null) { + if (entry.hash == hash && entry.key == key && entry.value != None) + return index + + if (firstDeletedIndex == -1 && entry.value == None) + firstDeletedIndex = index + + j += 1 + index = (index + j) & mask + entry = table(index) + } + + if (firstDeletedIndex == -1) index else firstDeletedIndex + } + + // TODO refactor `put` to extract `findOrAddEntry` and implement this in terms of that to avoid Some boxing. + override def update(key: Key, value: Value): Unit = put(key, value) + + @deprecatedOverriding("addOne should not be overridden in order to maintain consistency with put.", "2.11.0") + def addOne (kv: (Key, Value)): this.type = { put(kv._1, kv._2); this } + + @deprecatedOverriding("subtractOne should not be overridden in order to maintain consistency with remove.", "2.11.0") + def subtractOne (key: Key): this.type = { remove(key); this } + + override def put(key: Key, value: Value): Option[Value] = + put(key, hashOf(key), value) + + private def put(key: Key, hash: Int, value: Value): Option[Value] = { + if (2 * (size + deleted) > mask) growTable() + val index = findIndex(key, hash) + val entry = table(index) + if (entry == null) { + table(index) = new OpenEntry(key, hash, Some(value)) + modCount += 1 + size += 1 + None + } else { + val res = entry.value + if (entry.value == None) { + entry.key = key + entry.hash = hash + size += 1 + deleted -= 1 + modCount += 1 + } + entry.value = Some(value) + res + } + } + + /** Delete the hash table slot contained in the given entry. */ + @`inline` + private[this] def deleteSlot(entry: Entry) = { + entry.key = null.asInstanceOf[Key] + entry.hash = 0 + entry.value = None + + size -= 1 + deleted += 1 + } + + override def remove(key : Key): Option[Value] = { + val entry = table(findIndex(key, hashOf(key))) + if (entry != null && entry.value != None) { + val res = entry.value + deleteSlot(entry) + res + } else None + } + + def get(key : Key) : Option[Value] = { + val hash = hashOf(key) + var index = hash & mask + var entry = table(index) + var j = 0 + while(entry != null){ + if (entry.hash == hash && + entry.key == key){ + return entry.value + } + + j += 1 + index = (index + j) & mask + entry = table(index) + } + None + } + + /** An iterator over the elements of this map. Use of this iterator follows + * the same contract for concurrent modification as the foreach method. + * + * @return the iterator + */ + def iterator: Iterator[(Key, Value)] = new OpenHashMapIterator[(Key, Value)] { + override protected def nextResult(node: Entry): (Key, Value) = (node.key, node.value.get) + } + + override def keysIterator: Iterator[Key] = new OpenHashMapIterator[Key] { + override protected def nextResult(node: Entry): Key = node.key + } + override def valuesIterator: Iterator[Value] = new OpenHashMapIterator[Value] { + override protected def nextResult(node: Entry): Value = node.value.get + } + + private abstract class OpenHashMapIterator[A] extends AbstractIterator[A] { + private[this] var index = 0 + private[this] val initialModCount = modCount + + private[this] def advance(): Unit = { + if (initialModCount != modCount) throw new ConcurrentModificationException + while((index <= mask) && (table(index) == null || table(index).value == None)) index+=1 + } + + def hasNext = {advance(); index <= mask } + + def next() = { + advance() + val result = table(index) + index += 1 + nextResult(result) + } + protected def nextResult(node: Entry): A + } + + override def clone() = { + val it = new OpenHashMap[Key, Value] + foreachUndeletedEntry(entry => it.put(entry.key, entry.hash, entry.value.get)) + it + } + + /** Loop over the key, value mappings of this map. + * + * The behaviour of modifying the map during an iteration is as follows: + * - Deleting a mapping is always permitted. + * - Changing the value of mapping which is already present is permitted. + * - Anything else is not permitted. It will usually, but not always, throw an exception. + * + * @tparam U The return type of the specified function `f`, return result of which is ignored. + * @param f The function to apply to each key, value mapping. + */ + override def foreach[U](f : ((Key, Value)) => U): Unit = { + val startModCount = modCount + foreachUndeletedEntry(entry => { + if (modCount != startModCount) throw new ConcurrentModificationException + f((entry.key, entry.value.get))} + ) + } + override def foreachEntry[U](f : (Key, Value) => U): Unit = { + val startModCount = modCount + foreachUndeletedEntry(entry => { + if (modCount != startModCount) throw new ConcurrentModificationException + f(entry.key, entry.value.get)} + ) + } + + private[this] def foreachUndeletedEntry(f : Entry => Unit): Unit = { + table.foreach(entry => if (entry != null && entry.value != None) f(entry)) + } + + override def mapValuesInPlace(f : (Key, Value) => Value): this.type = { + foreachUndeletedEntry(entry => entry.value = Some(f(entry.key, entry.value.get))) + this + } + + override def filterInPlace(f : (Key, Value) => Boolean): this.type = { + foreachUndeletedEntry(entry => if (!f(entry.key, entry.value.get)) deleteSlot(entry)) + this + } + + override protected[this] def stringPrefix = "OpenHashMap" +} From 9021cfdba6b2331deba17b59f650e9ccb40864f2 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 19:33:46 +0100 Subject: [PATCH 58/89] Add MapView to stdlib --- tests/pos-special/stdlib/collection/Map.scala | 12 +- .../stdlib/collection/MapView.scala | 196 ++++++++++++++++++ 2 files changed, 203 insertions(+), 5 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/MapView.scala diff --git a/tests/pos-special/stdlib/collection/Map.scala b/tests/pos-special/stdlib/collection/Map.scala index 6816a1fd174a..8ab25a3c13e0 100644 --- a/tests/pos-special/stdlib/collection/Map.scala +++ b/tests/pos-special/stdlib/collection/Map.scala @@ -18,6 +18,7 @@ import scala.collection.generic.DefaultSerializable import scala.collection.mutable.StringBuilder import scala.util.hashing.MurmurHash3 import language.experimental.captureChecking +import caps.unsafe.unsafeAssumePure /** Base Map type */ trait Map[K, +V] @@ -103,8 +104,9 @@ trait Map[K, +V] trait MapOps[K, +V, +CC[_, _] <: IterableOps[_, AnyConstr, _], +C] extends IterableOps[(K, V), Iterable, C] with PartialFunction[K, V] { + this: MapOps[K, V, CC, C]^ => - override def view: MapView[K, V] = new MapView.Id(this) + override def view: MapView[K, V]^{this} = new MapView.Id(this) /** Returns a [[Stepper]] for the keys of this map. See method [[stepper]]. */ def keyStepper[S <: Stepper[_]](implicit shape: StepperShape[K, S]): S = { @@ -253,7 +255,7 @@ trait MapOps[K, +V, +CC[_, _] <: IterableOps[_, AnyConstr, _], +C] * the predicate `p`. The resulting map wraps the original map without copying any elements. */ @deprecated("Use .view.filterKeys(f). A future version will include a strict version of this method (for now, .view.filterKeys(p).toMap).", "2.13.0") - def filterKeys(p: K => Boolean): MapView[K, V] = new MapView.FilterKeys(this, p) + def filterKeys(p: K => Boolean): MapView[K, V]^{this, p} = new MapView.FilterKeys(this, p) /** Transforms this map by applying a function to every retrieved value. * @param f the function used to transform values of this map. @@ -261,7 +263,7 @@ trait MapOps[K, +V, +CC[_, _] <: IterableOps[_, AnyConstr, _], +C] * to `f(this(key))`. The resulting map wraps the original map without copying any elements. */ @deprecated("Use .view.mapValues(f). A future version will include a strict version of this method (for now, .view.mapValues(f).toMap).", "2.13.0") - def mapValues[W](f: V => W): MapView[K, W] = new MapView.MapValues(this, f) + def mapValues[W](f: V => W): MapView[K, W]^{this, f} = new MapView.MapValues(this, f) /** Defines the default value computation for the map, * returned when a key is not found @@ -354,7 +356,7 @@ trait MapOps[K, +V, +CC[_, _] <: IterableOps[_, AnyConstr, _], +C] @deprecated("Consider requiring an immutable Map.", "2.13.0") @`inline` def -- (keys: IterableOnce[K]^): C = { lazy val keysSet = keys.iterator.to(immutable.Set) - fromSpecific(this.view.filterKeys(k => !keysSet.contains(k))) + fromSpecific(this.view.filterKeys(k => !keysSet.contains(k))).unsafeAssumePure } @deprecated("Use ++ instead of ++: for collections of type Iterable", "2.13.0") @@ -375,7 +377,7 @@ object MapOps { */ @SerialVersionUID(3L) class WithFilter[K, +V, +IterableCC[_], +CC[_, _] <: IterableOps[_, AnyConstr, _]]( - self: MapOps[K, V, CC, _] with IterableOps[(K, V), IterableCC, _], + self: (MapOps[K, V, CC, _] with IterableOps[(K, V), IterableCC, _])^, p: ((K, V)) => Boolean ) extends IterableOps.WithFilter[(K, V), IterableCC](self, p) with Serializable { diff --git a/tests/pos-special/stdlib/collection/MapView.scala b/tests/pos-special/stdlib/collection/MapView.scala new file mode 100644 index 000000000000..ac9e88466052 --- /dev/null +++ b/tests/pos-special/stdlib/collection/MapView.scala @@ -0,0 +1,196 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import scala.annotation.nowarn +import scala.collection.MapView.SomeMapOps +import scala.collection.mutable.Builder +import language.experimental.captureChecking +import caps.unsafe.unsafeAssumePure + +trait MapView[K, +V] + extends MapOps[K, V, ({ type l[X, Y] = View[(X, Y)] })#l, View[(K, V)]] + with View[(K, V)] { + this: MapView[K, V]^ => + + override def view: MapView[K, V]^{this} = this + + // Ideally this returns a `View`, but bincompat + /** Creates a view over all keys of this map. + * + * @return the keys of this map as a view. + */ + override def keys: Iterable[K]^{this} = new MapView.Keys(this) + + // Ideally this returns a `View`, but bincompat + /** Creates a view over all values of this map. + * + * @return the values of this map as a view. + */ + override def values: Iterable[V]^{this} = new MapView.Values(this) + + /** Filters this map by retaining only keys satisfying a predicate. + * @param p the predicate used to test keys + * @return an immutable map consisting only of those key value pairs of this map where the key satisfies + * the predicate `p`. The resulting map wraps the original map without copying any elements. + */ + override def filterKeys(p: K => Boolean): MapView[K, V]^{this, p} = new MapView.FilterKeys(this, p) + + /** Transforms this map by applying a function to every retrieved value. + * @param f the function used to transform values of this map. + * @return a map view which maps every key of this map + * to `f(this(key))`. The resulting map wraps the original map without copying any elements. + */ + override def mapValues[W](f: V => W): MapView[K, W]^{this, f} = new MapView.MapValues(this, f) + + override def filter(pred: ((K, V)) => Boolean): MapView[K, V]^{this, pred} = new MapView.Filter(this, false, pred) + + override def filterNot(pred: ((K, V)) => Boolean): MapView[K, V]^{this, pred} = new MapView.Filter(this, true, pred) + + override def partition(p: ((K, V)) => Boolean): (MapView[K, V]^{this, p}, MapView[K, V]^{this, p}) = (filter(p), filterNot(p)) + + override def tapEach[U](f: ((K, V)) => U): MapView[K, V]^{this, f} = new MapView.TapEach(this, f) + + def mapFactory: MapViewFactory = MapView + + override def empty: MapView[K, V] = mapFactory.empty + + override def withFilter(p: ((K, V)) => Boolean): MapOps.WithFilter[K, V, View, ({ type l[X, Y] = View[(X, Y)] })#l]^{this, p} = new MapOps.WithFilter(this, p) + + override def toString: String = super[View].toString + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "MapView" +} + +object MapView extends MapViewFactory { + + /** An `IterableOps` whose collection type and collection type constructor are unknown */ + type SomeIterableConstr[X, Y] = IterableOps[_, AnyConstr, _] + /** A `MapOps` whose collection type and collection type constructor are (mostly) unknown */ + type SomeMapOps[K, +V] = MapOps[K, V, SomeIterableConstr, _] + + @SerialVersionUID(3L) + object EmptyMapView extends AbstractMapView[Any, Nothing] { + // !!! cc problem: crash when we replace the line with + // private val EmptyMapView: MapView[Any, Nothing] = new AbstractMapView[Any, Nothing] { + override def get(key: Any): Option[Nothing] = None + override def iterator: Iterator[Nothing] = Iterator.empty[Nothing] + override def knownSize: Int = 0 + override def isEmpty: Boolean = true + override def filterKeys(p: Any => Boolean): MapView[Any, Nothing] = this + override def mapValues[W](f: Nothing => W): MapView[Any, Nothing] = this + override def filter(pred: ((Any, Nothing)) => Boolean): MapView[Any, Nothing] = this + override def filterNot(pred: ((Any, Nothing)) => Boolean): MapView[Any, Nothing] = this + override def partition(p: ((Any, Nothing)) => Boolean): (MapView[Any, Nothing], MapView[Any, Nothing]) = (this, this) + } + + @SerialVersionUID(3L) + class Id[K, +V](underlying: SomeMapOps[K, V]^) extends AbstractMapView[K, V] { + def get(key: K): Option[V] = underlying.get(key) + def iterator: Iterator[(K, V)]^{this} = underlying.iterator + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + // Ideally this is public, but bincompat + @SerialVersionUID(3L) + private class Keys[K](underlying: SomeMapOps[K, _]^) extends AbstractView[K] { + def iterator: Iterator[K]^{this} = underlying.keysIterator + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + // Ideally this is public, but bincompat + @SerialVersionUID(3L) + private class Values[+V](underlying: SomeMapOps[_, V]^) extends AbstractView[V] { + def iterator: Iterator[V]^{this} = underlying.valuesIterator + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + @SerialVersionUID(3L) + class MapValues[K, +V, +W](underlying: SomeMapOps[K, V]^, f: V => W) extends AbstractMapView[K, W] { + def iterator: Iterator[(K, W)]^{this} = underlying.iterator.map(kv => (kv._1, f(kv._2))) + def get(key: K): Option[W] = underlying.get(key).map(f) + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + @SerialVersionUID(3L) + class FilterKeys[K, +V](underlying: SomeMapOps[K, V]^, p: K => Boolean) extends AbstractMapView[K, V] { + def iterator: Iterator[(K, V)]^{this} = underlying.iterator.filter { case (k, _) => p(k) } + def get(key: K): Option[V] = if (p(key)) underlying.get(key) else None + override def knownSize: Int = if (underlying.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.isEmpty + } + + @SerialVersionUID(3L) + class Filter[K, +V](underlying: SomeMapOps[K, V]^, isFlipped: Boolean, p: ((K, V)) => Boolean) extends AbstractMapView[K, V] { + def iterator: Iterator[(K, V)]^{this} = underlying.iterator.filterImpl(p, isFlipped) + def get(key: K): Option[V] = underlying.get(key) match { + case s @ Some(v) if p((key, v)) != isFlipped => s + case _ => None + } + override def knownSize: Int = if (underlying.knownSize == 0) 0 else super.knownSize + override def isEmpty: Boolean = iterator.isEmpty + } + + @SerialVersionUID(3L) + class TapEach[K, +V, +U](underlying: SomeMapOps[K, V]^, f: ((K, V)) => U) extends AbstractMapView[K, V] { + override def get(key: K): Option[V] = { + underlying.get(key) match { + case s @ Some(v) => + f((key, v)) + s + case None => None + } + } + override def iterator: Iterator[(K, V)]^{this} = underlying.iterator.tapEach(f) + override def knownSize: Int = underlying.knownSize + override def isEmpty: Boolean = underlying.isEmpty + } + + override def newBuilder[sealed X, sealed Y]: Builder[(X, Y), MapView[X, Y]] = mutable.HashMap.newBuilder[X, Y].mapResult(_.view) + + override def empty[K, V]: MapView[K, V] = EmptyMapView.asInstanceOf[MapView[K, V]] + + override def from[K, V](it: IterableOnce[(K, V)]^): View[(K, V)] = + View.from(it).unsafeAssumePure + // unsafeAssumePure needed here since MapViewFactory inherits from MapFactory, + // and the latter assumes maps are strict, so from's result captures nothing. + + override def from[K, V](it: SomeMapOps[K, V]^): MapView[K, V]^{it} = it match { + case mv: MapView[K, V] => mv + case other => new MapView.Id(other) + } + + override def apply[K, V](elems: (K, V)*): MapView[K, V] = from(elems.toMap) +} + +trait MapViewFactory extends collection.MapFactory[({ type l[X, Y] = View[(X, Y)]})#l] { + + def newBuilder[X, Y]: Builder[(X, Y), MapView[X, Y]] + + def empty[X, Y]: MapView[X, Y] + + def from[K, V](it: SomeMapOps[K, V]^): MapView[K, V]^{it} + + override def apply[K, V](elems: (K, V)*): MapView[K, V] = from(elems.toMap) +} + +/** Explicit instantiation of the `MapView` trait to reduce class file size in subclasses. */ +@SerialVersionUID(3L) +abstract class AbstractMapView[K, +V] extends AbstractView[(K, V)] with MapView[K, V]: + this: AbstractMapView[K, V]^ => + From cb66516b99c8fd2742c378415af932bdf07ce08b Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 21:34:19 +0100 Subject: [PATCH 59/89] Add StrictOptimizedMapOps to stdlib --- .../stdlib/collection/DefaultMap.scala | 21 +++++++ .../stdlib/collection/Searching.scala | 58 +++++++++++++++++++ .../collection/{mutable => }/SeqMap.scala | 22 +++---- .../collection/StrictOptimizedMapOps.scala | 50 ++++++++++++++++ 4 files changed, 141 insertions(+), 10 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/DefaultMap.scala create mode 100644 tests/pos-special/stdlib/collection/Searching.scala rename tests/pos-special/stdlib/collection/{mutable => }/SeqMap.scala (63%) create mode 100644 tests/pos-special/stdlib/collection/StrictOptimizedMapOps.scala diff --git a/tests/pos-special/stdlib/collection/DefaultMap.scala b/tests/pos-special/stdlib/collection/DefaultMap.scala new file mode 100644 index 000000000000..baa9eceadae5 --- /dev/null +++ b/tests/pos-special/stdlib/collection/DefaultMap.scala @@ -0,0 +1,21 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +import language.experimental.captureChecking + +/** A default map which builds a default `immutable.Map` implementation for all + * transformations. + */ +@deprecated("DefaultMap is no longer necessary; extend Map directly", "2.13.0") +trait DefaultMap[K, +V] extends Map[K, V] diff --git a/tests/pos-special/stdlib/collection/Searching.scala b/tests/pos-special/stdlib/collection/Searching.scala new file mode 100644 index 000000000000..f5139422e24c --- /dev/null +++ b/tests/pos-special/stdlib/collection/Searching.scala @@ -0,0 +1,58 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import scala.language.implicitConversions +import scala.collection.generic.IsSeq +import language.experimental.captureChecking + +object Searching { + + /** The result of performing a search on a sorted sequence + * + * Example usage: + * + * {{{ + * val list = List(1, 3, 4, 5) // list must be sorted before searching + * list.search(4) // Found(2) + * list.search(2) // InsertionPoint(1) + * }}} + * + * */ + sealed abstract class SearchResult { + /** The index corresponding to the element searched for in the sequence, if it was found, + * or the index where the element would be inserted in the sequence, if it was not in the sequence */ + def insertionPoint: Int + } + + /** The result of performing a search on a sorted sequence, where the element was found. + * + * @param foundIndex the index corresponding to the element searched for in the sequence + */ + case class Found(foundIndex: Int) extends SearchResult { + override def insertionPoint: Int = foundIndex + } + + /** The result of performing a search on a sorted sequence, where the element was not found + * + * @param insertionPoint the index where the element would be inserted in the sequence + */ + case class InsertionPoint(insertionPoint: Int) extends SearchResult + + @deprecated("Search methods are defined directly on SeqOps and do not require scala.collection.Searching any more", "2.13.0") + class SearchImpl[Repr, A](private val coll: SeqOps[A, AnyConstr, _]) extends AnyVal + + @deprecated("Search methods are defined directly on SeqOps and do not require scala.collection.Searching any more", "2.13.0") + implicit def search[Repr, A](coll: Repr)(implicit fr: IsSeq[Repr]): SearchImpl[Repr, fr.A] = + new SearchImpl(fr.conversion(coll)) +} diff --git a/tests/pos-special/stdlib/collection/mutable/SeqMap.scala b/tests/pos-special/stdlib/collection/SeqMap.scala similarity index 63% rename from tests/pos-special/stdlib/collection/mutable/SeqMap.scala rename to tests/pos-special/stdlib/collection/SeqMap.scala index 5740490223b2..a7f2c629b61d 100644 --- a/tests/pos-special/stdlib/collection/mutable/SeqMap.scala +++ b/tests/pos-special/stdlib/collection/SeqMap.scala @@ -10,13 +10,13 @@ * additional information regarding copyright ownership. */ -package scala -package collection -package mutable +package scala.collection import language.experimental.captureChecking +import scala.annotation.nowarn + /** - * A generic trait for ordered mutable maps. Concrete classes have to provide + * A generic trait for ordered maps. Concrete classes have to provide * functionality for the abstract methods in `SeqMap`. * * Note that when checking for equality [[SeqMap]] does not take into account @@ -24,16 +24,18 @@ import language.experimental.captureChecking * * @tparam K the type of the keys contained in this linked map. * @tparam V the type of the values associated with the keys in this linked map. - * - * @define coll mutable Seq map - * @define Coll `mutable.SeqMap` + * @define coll immutable seq map + * @define Coll `immutable.SeqMap` */ -trait SeqMap[K, V] extends Map[K, V] - with collection.SeqMap[K, V] +trait SeqMap[K, +V] extends Map[K, V] with MapOps[K, V, SeqMap, SeqMap[K, V]] with MapFactoryDefaults[K, V, SeqMap, Iterable] { + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "SeqMap" + override def mapFactory: MapFactory[SeqMap] = SeqMap } -object SeqMap extends MapFactory.Delegate[SeqMap](LinkedHashMap) +object SeqMap extends MapFactory.Delegate[immutable.SeqMap](immutable.SeqMap) + diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedMapOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedMapOps.scala new file mode 100644 index 000000000000..a9c5e0af43b3 --- /dev/null +++ b/tests/pos-special/stdlib/collection/StrictOptimizedMapOps.scala @@ -0,0 +1,50 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +import language.experimental.captureChecking + +/** + * Trait that overrides map operations to take advantage of strict builders. + * + * @tparam K Type of keys + * @tparam V Type of values + * @tparam CC Collection type constructor + * @tparam C Collection type + */ +trait StrictOptimizedMapOps[K, +V, +CC[_, _] <: IterableOps[_, AnyConstr, _], +C] + extends MapOps[K, V, CC, C] + with StrictOptimizedIterableOps[(K, V), Iterable, C] + with Pure { + + override def map[K2, V2](f: ((K, V)) => (K2, V2)): CC[K2, V2] = + strictOptimizedMap(mapFactory.newBuilder, f) + + override def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)]^): CC[K2, V2] = + strictOptimizedFlatMap(mapFactory.newBuilder, f) + + override def concat[V2 >: V](suffix: IterableOnce[(K, V2)]^): CC[K, V2] = + strictOptimizedConcat(suffix, mapFactory.newBuilder) + + override def collect[K2, V2](pf: PartialFunction[(K, V), (K2, V2)]): CC[K2, V2] = + strictOptimizedCollect(mapFactory.newBuilder, pf) + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + override def + [V1 >: V](elem1: (K, V1), elem2: (K, V1), elems: (K, V1)*): CC[K, V1] = { + val b = mapFactory.newBuilder[K, V1] + b ++= this + b += elem1 + b += elem2 + if (elems.nonEmpty) b ++= elems + b.result() + } +} From be20a7c58064e63b0402b728ba8b2452cd1809cc Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 21:41:25 +0100 Subject: [PATCH 60/89] Add collection/SortedMap to stdlib --- .../stdlib/collection/SortedMap.scala | 222 ++++++++++++++++++ .../stdlib/collection/mutable/SortedMap.scala | 2 +- 2 files changed, 223 insertions(+), 1 deletion(-) create mode 100644 tests/pos-special/stdlib/collection/SortedMap.scala diff --git a/tests/pos-special/stdlib/collection/SortedMap.scala b/tests/pos-special/stdlib/collection/SortedMap.scala new file mode 100644 index 000000000000..7b9381ebb078 --- /dev/null +++ b/tests/pos-special/stdlib/collection/SortedMap.scala @@ -0,0 +1,222 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.annotation.{implicitNotFound, nowarn} +import language.experimental.captureChecking + +/** A Map whose keys are sorted according to a [[scala.math.Ordering]]*/ +trait SortedMap[K, +V] + extends Map[K, V] + with SortedMapOps[K, V, SortedMap, SortedMap[K, V]] + with SortedMapFactoryDefaults[K, V, SortedMap, Iterable, Map]{ + + def unsorted: Map[K, V] = this + + def sortedMapFactory: SortedMapFactory[SortedMap] = SortedMap + + @nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""") + override protected[this] def stringPrefix: String = "SortedMap" + + override def equals(that: Any): Boolean = that match { + case _ if this eq that.asInstanceOf[AnyRef] => true + case sm: SortedMap[K @unchecked, _] if sm.ordering == this.ordering => + (sm canEqual this) && + (this.size == sm.size) && { + val i1 = this.iterator + val i2 = sm.iterator + var allEqual = true + while (allEqual && i1.hasNext) { + val kv1 = i1.next() + val kv2 = i2.next() + allEqual = ordering.equiv(kv1._1, kv2._1) && kv1._2 == kv2._2 + } + allEqual + } + case _ => super.equals(that) + } +} + +trait SortedMapOps[K, +V, +CC[X, Y] <: Map[X, Y] with SortedMapOps[X, Y, CC, _], +C <: SortedMapOps[K, V, CC, C]] + extends MapOps[K, V, Map, C] + with SortedOps[K, C] + with Pure { + + /** The companion object of this sorted map, providing various factory methods. + * + * @note When implementing a custom collection type and refining `CC` to the new type, this + * method needs to be overridden to return a factory for the new type (the compiler will + * issue an error otherwise). + */ + def sortedMapFactory: SortedMapFactory[CC] + + /** Similar to `mapFromIterable`, but returns a SortedMap collection type. + * Note that the return type is now `CC[K2, V2]`. + */ + @`inline` protected final def sortedMapFromIterable[K2, V2](it: Iterable[(K2, V2)])(implicit ordering: Ordering[K2]): CC[K2, V2] = sortedMapFactory.from(it) + + def unsorted: Map[K, V] + + /** + * Creates an iterator over all the key/value pairs + * contained in this map having a key greater than or + * equal to `start` according to the ordering of + * this map. x.iteratorFrom(y) is equivalent + * to but often more efficient than x.from(y).iterator. + * + * @param start The lower bound (inclusive) + * on the keys to be returned + */ + def iteratorFrom(start: K): Iterator[(K, V)] + + /** + * Creates an iterator over all the keys(or elements) contained in this + * collection greater than or equal to `start` + * according to the ordering of this collection. x.keysIteratorFrom(y) + * is equivalent to but often more efficient than + * x.from(y).keysIterator. + * + * @param start The lower bound (inclusive) + * on the keys to be returned + */ + def keysIteratorFrom(start: K): Iterator[K] + + /** + * Creates an iterator over all the values contained in this + * map that are associated with a key greater than or equal to `start` + * according to the ordering of this map. x.valuesIteratorFrom(y) is + * equivalent to but often more efficient than + * x.from(y).valuesIterator. + * + * @param start The lower bound (inclusive) + * on the keys to be returned + */ + def valuesIteratorFrom(start: K): Iterator[V] = iteratorFrom(start).map(_._2) + + def firstKey: K = head._1 + def lastKey: K = last._1 + + /** Find the element with smallest key larger than or equal to a given key. + * @param key The given key. + * @return `None` if there is no such node. + */ + def minAfter(key: K): Option[(K, V)] = rangeFrom(key).headOption + + /** Find the element with largest key less than a given key. + * @param key The given key. + * @return `None` if there is no such node. + */ + def maxBefore(key: K): Option[(K, V)] = rangeUntil(key).lastOption + + def rangeTo(to: K): C = { + val i = keySet.rangeFrom(to).iterator + if (i.isEmpty) return coll + val next = i.next() + if (ordering.compare(next, to) == 0) + if (i.isEmpty) coll + else rangeUntil(i.next()) + else + rangeUntil(next) + } + + override def keySet: SortedSet[K] = new KeySortedSet + + /** The implementation class of the set returned by `keySet` */ + protected class KeySortedSet extends SortedSet[K] with GenKeySet with GenKeySortedSet { + def diff(that: Set[K]): SortedSet[K] = fromSpecific(view.filterNot(that)) + def rangeImpl(from: Option[K], until: Option[K]): SortedSet[K] = { + val map = SortedMapOps.this.rangeImpl(from, until) + new map.KeySortedSet + } + } + + /** A generic trait that is reused by sorted keyset implementations */ + protected trait GenKeySortedSet extends GenKeySet { this: SortedSet[K] => + implicit def ordering: Ordering[K] = SortedMapOps.this.ordering + def iteratorFrom(start: K): Iterator[K] = SortedMapOps.this.keysIteratorFrom(start) + } + + // And finally, we add new overloads taking an ordering + /** Builds a new sorted map by applying a function to all elements of this $coll. + * + * @param f the function to apply to each element. + * @return a new $coll resulting from applying the given function + * `f` to each element of this $coll and collecting the results. + */ + def map[K2, V2](f: ((K, V)) => (K2, V2))(implicit @implicitNotFound(SortedMapOps.ordMsg) ordering: Ordering[K2]): CC[K2, V2] = + sortedMapFactory.from(new View.Map[(K, V), (K2, V2)](this, f)) + + /** Builds a new sorted map by applying a function to all elements of this $coll + * and using the elements of the resulting collections. + * + * @param f the function to apply to each element. + * @return a new $coll resulting from applying the given collection-valued function + * `f` to each element of this $coll and concatenating the results. + */ + def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)])(implicit @implicitNotFound(SortedMapOps.ordMsg) ordering: Ordering[K2]): CC[K2, V2] = + sortedMapFactory.from(new View.FlatMap(this, f)) + + /** Builds a new sorted map by applying a partial function to all elements of this $coll + * on which the function is defined. + * + * @param pf the partial function which filters and maps the $coll. + * @return a new $coll resulting from applying the given partial function + * `pf` to each element on which it is defined and collecting the results. + * The order of the elements is preserved. + */ + def collect[K2, V2](pf: PartialFunction[(K, V), (K2, V2)])(implicit @implicitNotFound(SortedMapOps.ordMsg) ordering: Ordering[K2]): CC[K2, V2] = + sortedMapFactory.from(new View.Collect(this, pf)) + + override def concat[V2 >: V](suffix: IterableOnce[(K, V2)]^): CC[K, V2] = sortedMapFactory.from(suffix match { + case it: Iterable[(K, V2)] => new View.Concat(this, it) + case _ => iterator.concat(suffix.iterator) + })(ordering) + + /** Alias for `concat` */ + @`inline` override final def ++ [V2 >: V](xs: IterableOnce[(K, V2)]^): CC[K, V2] = concat(xs) + + @deprecated("Consider requiring an immutable Map or fall back to Map.concat", "2.13.0") + override def + [V1 >: V](kv: (K, V1)): CC[K, V1] = sortedMapFactory.from(new View.Appended(this, kv))(ordering) + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + override def + [V1 >: V](elem1: (K, V1), elem2: (K, V1), elems: (K, V1)*): CC[K, V1] = sortedMapFactory.from(new View.Concat(new View.Appended(new View.Appended(this, elem1), elem2), elems))(ordering) +} + +object SortedMapOps { + private[collection] final val ordMsg = "No implicit Ordering[${K2}] found to build a SortedMap[${K2}, ${V2}]. You may want to upcast to a Map[${K}, ${V}] first by calling `unsorted`." + + /** Specializes `MapWithFilter` for sorted Map collections + * + * @define coll sorted map collection + */ + class WithFilter[K, +V, +IterableCC[_], +MapCC[X, Y] <: Map[X, Y], +CC[X, Y] <: Map[X, Y] with SortedMapOps[X, Y, CC, _]]( + self: SortedMapOps[K, V, CC, _] with MapOps[K, V, MapCC, _] with IterableOps[(K, V), IterableCC, _], + p: ((K, V)) => Boolean + ) extends MapOps.WithFilter[K, V, IterableCC, MapCC](self, p) { + + def map[K2 : Ordering, V2](f: ((K, V)) => (K2, V2)): CC[K2, V2] = + self.sortedMapFactory.from(new View.Map(filtered, f)) + + def flatMap[K2 : Ordering, V2](f: ((K, V)) => IterableOnce[(K2, V2)]^): CC[K2, V2] = + self.sortedMapFactory.from(new View.FlatMap(filtered, f)) + + override def withFilter(q: ((K, V)) => Boolean): WithFilter[K, V, IterableCC, MapCC, CC]^{this, q} = + new WithFilter[K, V, IterableCC, MapCC, CC](self, (kv: (K, V)) => p(kv) && q(kv)) + + } + +} + +@SerialVersionUID(3L) +object SortedMap extends SortedMapFactory.Delegate[SortedMap](immutable.SortedMap) diff --git a/tests/pos-special/stdlib/collection/mutable/SortedMap.scala b/tests/pos-special/stdlib/collection/mutable/SortedMap.scala index ff0e95c747a5..8017177f5720 100644 --- a/tests/pos-special/stdlib/collection/mutable/SortedMap.scala +++ b/tests/pos-special/stdlib/collection/mutable/SortedMap.scala @@ -92,7 +92,7 @@ object SortedMap extends SortedMapFactory.Delegate[SortedMap](TreeMap) { override def empty: WithDefault[K, V] = new WithDefault[K, V](underlying.empty, defaultValue) - override def concat[V2 >: V](suffix: collection.IterableOnce[(K, V2)]): SortedMap[K, V2] = + override def concat[V2 >: V](suffix: collection.IterableOnce[(K, V2)]^): SortedMap[K, V2] = underlying.concat(suffix).withDefault(defaultValue) override protected def fromSpecific(coll: scala.collection.IterableOnce[(K, V)]^): WithDefault[K, V] = From 766b02051881addf71301c46bc99356c2c25432b Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 21:46:24 +0100 Subject: [PATCH 61/89] Add more Ops classes to stdlib --- .../stdlib/collection/SortedOps.scala | 91 +++++++++++++++++++ .../StrictOptimizedSortedMapOps.scala | 47 ++++++++++ .../StrictOptimizedSortedSetOps.scala | 42 +++++++++ 3 files changed, 180 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/SortedOps.scala create mode 100644 tests/pos-special/stdlib/collection/StrictOptimizedSortedMapOps.scala create mode 100644 tests/pos-special/stdlib/collection/StrictOptimizedSortedSetOps.scala diff --git a/tests/pos-special/stdlib/collection/SortedOps.scala b/tests/pos-special/stdlib/collection/SortedOps.scala new file mode 100644 index 000000000000..16751d86d9d5 --- /dev/null +++ b/tests/pos-special/stdlib/collection/SortedOps.scala @@ -0,0 +1,91 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import language.experimental.captureChecking + +/** Base trait for sorted collections */ +trait SortedOps[A, +C] { + + def ordering: Ordering[A] + + /** Returns the first key of the collection. */ + def firstKey: A + + /** Returns the last key of the collection. */ + def lastKey: A + + /** Comparison function that orders keys. */ + @deprecated("Use ordering.compare instead", "2.13.0") + @deprecatedOverriding("Use ordering.compare instead", "2.13.0") + @inline def compare(k0: A, k1: A): Int = ordering.compare(k0, k1) + + /** Creates a ranged projection of this collection. Any mutations in the + * ranged projection will update this collection and vice versa. + * + * Note: keys are not guaranteed to be consistent between this collection + * and the projection. This is the case for buffers where indexing is + * relative to the projection. + * + * @param from The lower-bound (inclusive) of the ranged projection. + * `None` if there is no lower bound. + * @param until The upper-bound (exclusive) of the ranged projection. + * `None` if there is no upper bound. + */ + def rangeImpl(from: Option[A], until: Option[A]): C + + /** Creates a ranged projection of this collection with both a lower-bound + * and an upper-bound. + * + * @param from The lower-bound (inclusive) of the ranged projection. + * @param until The upper-bound (exclusive) of the ranged projection. + */ + def range(from: A, until: A): C = rangeImpl(Some(from), Some(until)) + + /** Creates a ranged projection of this collection with no upper-bound. + * + * @param from The lower-bound (inclusive) of the ranged projection. + */ + @deprecated("Use rangeFrom", "2.13.0") + final def from(from: A): C = rangeFrom(from) + + /** Creates a ranged projection of this collection with no upper-bound. + * + * @param from The lower-bound (inclusive) of the ranged projection. + */ + def rangeFrom(from: A): C = rangeImpl(Some(from), None) + + /** Creates a ranged projection of this collection with no lower-bound. + * + * @param until The upper-bound (exclusive) of the ranged projection. + */ + @deprecated("Use rangeUntil", "2.13.0") + final def until(until: A): C = rangeUntil(until) + + /** Creates a ranged projection of this collection with no lower-bound. + * + * @param until The upper-bound (exclusive) of the ranged projection. + */ + def rangeUntil(until: A): C = rangeImpl(None, Some(until)) + + /** Create a range projection of this collection with no lower-bound. + * @param to The upper-bound (inclusive) of the ranged projection. + */ + @deprecated("Use rangeTo", "2.13.0") + final def to(to: A): C = rangeTo(to) + + /** Create a range projection of this collection with no lower-bound. + * @param to The upper-bound (inclusive) of the ranged projection. + */ + def rangeTo(to: A): C +} diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedSortedMapOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedSortedMapOps.scala new file mode 100644 index 000000000000..9a9e6e367922 --- /dev/null +++ b/tests/pos-special/stdlib/collection/StrictOptimizedSortedMapOps.scala @@ -0,0 +1,47 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection + +import scala.annotation.implicitNotFound +import language.experimental.captureChecking + +/** + * Trait that overrides sorted map operations to take advantage of strict builders. + * + * @tparam K Type of keys + * @tparam V Type of values + * @tparam CC Collection type constructor + * @tparam C Collection type + */ +trait StrictOptimizedSortedMapOps[K, +V, +CC[X, Y] <: Map[X, Y] with SortedMapOps[X, Y, CC, _], +C <: SortedMapOps[K, V, CC, C]] + extends SortedMapOps[K, V, CC, C] + with StrictOptimizedMapOps[K, V, Map, C] { + + override def map[K2, V2](f: ((K, V)) => (K2, V2))(implicit @implicitNotFound(SortedMapOps.ordMsg) ordering: Ordering[K2]): CC[K2, V2] = + strictOptimizedMap(sortedMapFactory.newBuilder, f) + + override def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)])(implicit @implicitNotFound(SortedMapOps.ordMsg) ordering: Ordering[K2]): CC[K2, V2] = + strictOptimizedFlatMap(sortedMapFactory.newBuilder, f) + + override def concat[V2 >: V](xs: IterableOnce[(K, V2)]^): CC[K, V2] = + strictOptimizedConcat(xs, sortedMapFactory.newBuilder(ordering)) + + override def collect[K2, V2](pf: PartialFunction[(K, V), (K2, V2)])(implicit @implicitNotFound(SortedMapOps.ordMsg) ordering: Ordering[K2]): CC[K2, V2] = + strictOptimizedCollect(sortedMapFactory.newBuilder, pf) + + @deprecated("Use ++ with an explicit collection argument instead of + with varargs", "2.13.0") + override def + [V1 >: V](elem1: (K, V1), elem2: (K, V1), elems: (K, V1)*): CC[K, V1] = { + val m = ((this + elem1).asInstanceOf[Map[K, V]] + elem2).asInstanceOf[CC[K, V1]] + if(elems.isEmpty) m else m.concat(elems).asInstanceOf[CC[K, V1]] + } +} diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedSortedSetOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedSortedSetOps.scala new file mode 100644 index 000000000000..ded7deabccca --- /dev/null +++ b/tests/pos-special/stdlib/collection/StrictOptimizedSortedSetOps.scala @@ -0,0 +1,42 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.annotation.implicitNotFound +import scala.annotation.unchecked.uncheckedVariance + +/** + * Trait that overrides sorted set operations to take advantage of strict builders. + * + * @tparam A Elements type + * @tparam CC Collection type constructor + * @tparam C Collection type + */ +trait StrictOptimizedSortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]] + extends SortedSetOps[A, CC, C] + with StrictOptimizedSetOps[A, Set, C] { + + override def map[B](f: A => B)(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] = + strictOptimizedMap(sortedIterableFactory.newBuilder, f) + + override def flatMap[B](f: A => IterableOnce[B])(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] = + strictOptimizedFlatMap(sortedIterableFactory.newBuilder, f) + + override def zip[B](that: IterableOnce[B])(implicit @implicitNotFound(SortedSetOps.zipOrdMsg) ev: Ordering[(A @uncheckedVariance, B)]): CC[(A @uncheckedVariance, B)] = + strictOptimizedZip(that, sortedIterableFactory.newBuilder[(A, B)]) + + override def collect[B](pf: PartialFunction[A, B])(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] = + strictOptimizedCollect(sortedIterableFactory.newBuilder, pf) + +} From 36975c108fa46280964c39043380d6a48a8b8c32 Mon Sep 17 00:00:00 2001 From: odersky Date: Wed, 1 Nov 2023 21:51:15 +0100 Subject: [PATCH 62/89] Add remaining collection classes to stdlib --- .../stdlib/collection/StringParsers.scala | 320 ++++++++++++++++++ .../stdlib/collection/package.scala | 81 +++++ 2 files changed, 401 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/StringParsers.scala create mode 100644 tests/pos-special/stdlib/collection/package.scala diff --git a/tests/pos-special/stdlib/collection/StringParsers.scala b/tests/pos-special/stdlib/collection/StringParsers.scala new file mode 100644 index 000000000000..47281815da71 --- /dev/null +++ b/tests/pos-special/stdlib/collection/StringParsers.scala @@ -0,0 +1,320 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection + +import scala.annotation.tailrec +import language.experimental.captureChecking + +/** A module containing the implementations of parsers from strings to numeric types, and boolean + */ +private[scala] object StringParsers { + + //compile-time constant helpers + + //Int.MinValue == -2147483648 + private final val intOverflowBoundary = -214748364 + private final val intOverflowDigit = 9 + //Long.MinValue == -9223372036854775808L + private final val longOverflowBoundary = -922337203685477580L + private final val longOverflowDigit = 9 + + @inline + private[this] final def decValue(ch: Char): Int = java.lang.Character.digit(ch, 10) + + @inline + private[this] final def stepToOverflow(from: String, len: Int, agg: Int, isPositive: Boolean, min: Int): Option[Int] = { + @tailrec + def rec(i: Int, agg: Int): Option[Int] = + if (agg < min) None + else if (i == len) { + if (!isPositive) Some(agg) + else if (agg == min) None + else Some(-agg) + } + else { + val digit = decValue(from.charAt(i)) + if (digit == -1) None + else rec(i + 1, agg * 10 - digit) + } + rec(1, agg) + } + + @inline + private[this] final def isDigit(c: Char): Boolean = c >= '0' && c <= '9' + + //bool + @inline + final def parseBool(from: String): Option[Boolean] = + if (from.equalsIgnoreCase("true")) Some(true) + else if (from.equalsIgnoreCase("false")) Some(false) + else None + + //integral types + final def parseByte(from: String): Option[Byte] = { + val len = from.length() + //empty strings parse to None + if (len == 0) None + else { + val first = from.charAt(0) + val v = decValue(first) + if (len == 1) { + //"+" and "-" parse to None + if (v > -1) Some(v.toByte) + else None + } + else if (v > -1) stepToOverflow(from, len, -v, true, Byte.MinValue).map(_.toByte) + else if (first == '+') stepToOverflow(from, len, 0, true, Byte.MinValue).map(_.toByte) + else if (first == '-') stepToOverflow(from, len, 0, false, Byte.MinValue).map(_.toByte) + else None + } + } + + final def parseShort(from: String): Option[Short] = { + val len = from.length() + //empty strings parse to None + if (len == 0) None + else { + val first = from.charAt(0) + val v = decValue(first) + if (len == 1) { + //"+" and "-" parse to None + if (v > -1) Some(v.toShort) + else None + } + else if (v > -1) stepToOverflow(from, len, -v, true, Short.MinValue).map(_.toShort) + else if (first == '+') stepToOverflow(from, len, 0, true, Short.MinValue).map(_.toShort) + else if (first == '-') stepToOverflow(from, len, 0, false, Short.MinValue).map(_.toShort) + else None + } + } + + final def parseInt(from: String): Option[Int] = { + val len = from.length() + + @tailrec + def step(i: Int, agg: Int, isPositive: Boolean): Option[Int] = { + if (i == len) { + if (!isPositive) Some(agg) + else if (agg == Int.MinValue) None + else Some(-agg) + } + else if (agg < intOverflowBoundary) None + else { + val digit = decValue(from.charAt(i)) + if (digit == -1 || (agg == intOverflowBoundary && digit == intOverflowDigit)) None + else step(i + 1, (agg * 10) - digit, isPositive) + } + } + //empty strings parse to None + if (len == 0) None + else { + val first = from.charAt(0) + val v = decValue(first) + if (len == 1) { + //"+" and "-" parse to None + if (v > -1) Some(v) + else None + } + else if (v > -1) step(1, -v, true) + else if (first == '+') step(1, 0, true) + else if (first == '-') step(1, 0, false) + else None + } + } + + final def parseLong(from: String): Option[Long] = { + //like parseInt, but Longer + val len = from.length() + + @tailrec + def step(i: Int, agg: Long, isPositive: Boolean): Option[Long] = { + if (i == len) { + if (isPositive && agg == Long.MinValue) None + else if (isPositive) Some(-agg) + else Some(agg) + } + else if (agg < longOverflowBoundary) None + else { + val digit = decValue(from.charAt(i)) + if (digit == -1 || (agg == longOverflowBoundary && digit == longOverflowDigit)) None + else step(i + 1, agg * 10 - digit, isPositive) + } + } + //empty strings parse to None + if (len == 0) None + else { + val first = from.charAt(0) + val v = decValue(first).toLong + if (len == 1) { + //"+" and "-" parse to None + if (v > -1) Some(v) + else None + } + else if (v > -1) step(1, -v, true) + else if (first == '+') step(1, 0, true) + else if (first == '-') step(1, 0, false) + else None + } + } + + //floating point + final def checkFloatFormat(format: String): Boolean = { + //indices are tracked with a start index which points *at* the first index + //and an end index which points *after* the last index + //so that slice length === end - start + //thus start == end <=> empty slice + //and format.substring(start, end) is equivalent to the slice + + //some utilities for working with index bounds into the original string + @inline + def forAllBetween(start: Int, end: Int, pred: Char => Boolean): Boolean = { + @tailrec + def rec(i: Int): Boolean = i >= end || pred(format.charAt(i)) && rec(i + 1) + rec(start) + } + + //one after last index for the predicate to hold, or `from` if none hold + //may point after the end of the string + @inline + def skipIndexWhile(predicate: Char => Boolean, from: Int, until: Int): Int = { + @tailrec @inline + def rec(i: Int): Int = if ((i < until) && predicate(format.charAt(i))) rec(i + 1) + else i + rec(from) + } + + + def isHexFloatLiteral(startIndex: Int, endIndex: Int): Boolean = { + def isHexDigit(ch: Char) = ((ch >= '0' && ch <= '9') || + (ch >= 'a' && ch <= 'f') || + (ch >= 'A' && ch <= 'F')) + + def prefixOK(startIndex: Int, endIndex: Int): Boolean = { + val len = endIndex - startIndex + (len > 0) && { + //the prefix part is + //hexDigits + //hexDigits. + //hexDigits.hexDigits + //.hexDigits + //but not . + if (format.charAt(startIndex) == '.') { + (len > 1) && forAllBetween(startIndex + 1, endIndex, isHexDigit) + } else { + val noLeading = skipIndexWhile(isHexDigit, startIndex, endIndex) + (noLeading >= endIndex) || + ((format.charAt(noLeading) == '.') && forAllBetween(noLeading + 1, endIndex, isHexDigit)) + } + } + } + + def postfixOK(startIndex: Int, endIndex: Int): Boolean = + (startIndex < endIndex) && { + (forAllBetween(startIndex, endIndex, isDigit)) || { + val startchar = format.charAt(startIndex) + (startchar == '+' || startchar == '-') && + (endIndex - startIndex > 1) && + forAllBetween(startIndex + 1, endIndex, isDigit) + } + } + // prefix [pP] postfix + val pIndex = format.indexWhere(ch => ch == 'p' || ch == 'P', startIndex) + (pIndex <= endIndex) && prefixOK(startIndex, pIndex) && postfixOK(pIndex + 1, endIndex) + } + + def isDecFloatLiteral(startIndex: Int, endIndex: Int): Boolean = { + //invariant: endIndex > startIndex + + def isExp(c: Char): Boolean = c == 'e' || c == 'E' + + def expOK(startIndex: Int, endIndex: Int): Boolean = + (startIndex < endIndex) && { + val startChar = format.charAt(startIndex) + if (startChar == '+' || startChar == '-') + (endIndex > (startIndex + 1)) && + skipIndexWhile(isDigit, startIndex + 1, endIndex) == endIndex + else skipIndexWhile(isDigit, startIndex, endIndex) == endIndex + } + + //significant can be one of + //* digits.digits + //* .digits + //* digits. + //but not just . + val startChar = format.charAt(startIndex) + if (startChar == '.') { + val noSignificant = skipIndexWhile(isDigit, startIndex + 1, endIndex) + // a digit is required followed by optional exp + (noSignificant > startIndex + 1) && (noSignificant >= endIndex || + isExp(format.charAt(noSignificant)) && expOK(noSignificant + 1, endIndex) + ) + } + else if (isDigit(startChar)) { + // one set of digits, then optionally a period, then optionally another set of digits, then optionally an exponent + val noInt = skipIndexWhile(isDigit, startIndex, endIndex) + // just the digits + (noInt == endIndex) || { + if (format.charAt(noInt) == '.') { + val noSignificant = skipIndexWhile(isDigit, noInt + 1, endIndex) + (noSignificant >= endIndex) || //no exponent + isExp(format.charAt(noSignificant)) && expOK(noSignificant + 1, endIndex) + } else + isExp(format.charAt(noInt)) && expOK(noInt + 1, endIndex) + } + } + else false + } + + //count 0x00 to 0x20 as "whitespace", and nothing else + val unspacedStart = format.indexWhere(ch => ch.toInt > 0x20) + val unspacedEnd = format.lastIndexWhere(ch => ch.toInt > 0x20) + 1 + + if (unspacedStart == -1 || unspacedStart >= unspacedEnd || unspacedEnd <= 0) false + else { + //all formats can have a sign + val unsigned = { + val startchar = format.charAt(unspacedStart) + if (startchar == '-' || startchar == '+') unspacedStart + 1 else unspacedStart + } + if (unsigned >= unspacedEnd) false + //that's it for NaN and Infinity + else if (format.charAt(unsigned) == 'N') format.substring(unsigned, unspacedEnd) == "NaN" + else if (format.charAt(unsigned) == 'I') format.substring(unsigned, unspacedEnd) == "Infinity" + else { + //all other formats can have a format suffix + val desuffixed = { + val endchar = format.charAt(unspacedEnd - 1) + if (endchar == 'f' || endchar == 'F' || endchar == 'd' || endchar == 'D') unspacedEnd - 1 + else unspacedEnd + } + val len = desuffixed - unsigned + if (len <= 0) false + else if (len >= 2 && (format.charAt(unsigned + 1) == 'x' || format.charAt(unsigned + 1) == 'X')) + format.charAt(unsigned) == '0' && isHexFloatLiteral(unsigned + 2, desuffixed) + else isDecFloatLiteral(unsigned, desuffixed) + } + } + } + + @inline + def parseFloat(from: String): Option[Float] = + if (checkFloatFormat(from)) Some(java.lang.Float.parseFloat(from)) + else None + + @inline + def parseDouble(from: String): Option[Double] = + if (checkFloatFormat(from)) Some(java.lang.Double.parseDouble(from)) + else None + +} diff --git a/tests/pos-special/stdlib/collection/package.scala b/tests/pos-special/stdlib/collection/package.scala new file mode 100644 index 000000000000..ad4686be1fb2 --- /dev/null +++ b/tests/pos-special/stdlib/collection/package.scala @@ -0,0 +1,81 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +import language.experimental.captureChecking + +package object collection { + @deprecated("Use Iterable instead of Traversable", "2.13.0") + type Traversable[+X] = Iterable[X] + @deprecated("Use Iterable instead of Traversable", "2.13.0") + val Traversable = Iterable + @deprecated("Use IterableOnce instead of TraversableOnce", "2.13.0") + type TraversableOnce[+X] = IterableOnce[X] + @deprecated("Use IterableOnce instead of TraversableOnce", "2.13.0") + val TraversableOnce = IterableOnce + @deprecated("Use SeqOps instead of SeqLike", "2.13.0") + type SeqLike[A, T] = SeqOps[A, Seq, T] + @deprecated("Use SeqOps (for the methods) or IndexedSeqOps (for fast indexed access) instead of ArrayLike", "2.13.0") + type ArrayLike[A] = SeqOps[A, Seq, Seq[A]] + + @deprecated("Gen* collection types have been removed", "2.13.0") + type GenTraversableOnce[+X] = IterableOnce[X] + @deprecated("Gen* collection types have been removed", "2.13.0") + val GenTraversableOnce = IterableOnce + @deprecated("Gen* collection types have been removed", "2.13.0") + type GenTraversable[+X] = Iterable[X] + @deprecated("Gen* collection types have been removed", "2.13.0") + val GenTraversable = Iterable + @deprecated("Gen* collection types have been removed", "2.13.0") + type GenIterable[+X] = Iterable[X] + @deprecated("Gen* collection types have been removed", "2.13.0") + val GenIterable = Iterable + @deprecated("Gen* collection types have been removed", "2.13.0") + type GenSeq[+X] = Seq[X] + @deprecated("Gen* collection types have been removed", "2.13.0") + val GenSeq = Seq + @deprecated("Gen* collection types have been removed", "2.13.0") + type GenSet[X] = Set[X] + @deprecated("Gen* collection types have been removed", "2.13.0") + val GenSet = Set + @deprecated("Gen* collection types have been removed", "2.13.0") + type GenMap[K, +V] = Map[K, V] + @deprecated("Gen* collection types have been removed", "2.13.0") + val GenMap = Map + + /** Needed to circumvent a difficulty between dotty and scalac concerning + * the right top type for a type parameter of kind * -> *. + * In Scalac, we can provide `Any`, as `Any` is kind-polymorphic. In dotty this is not allowed. + * In dotty, we can provide `[X] => Any`. But Scalac does not know lambda syntax. + */ + private[scala] type AnyConstr[X] = Any + + /** An extractor used to head/tail deconstruct sequences. */ + object +: { + /** Splits a sequence into head +: tail. + * @return Some((head, tail)) if sequence is non-empty. None otherwise. + */ + def unapply[A, CC[_] <: Seq[_], C <: SeqOps[A, CC, C]](t: C with SeqOps[A, CC, C]): Option[(A, C)] = + if(t.isEmpty) None + else Some(t.head -> t.tail) + } + + /** An extractor used to init/last deconstruct sequences. */ + object :+ { + /** Splits a sequence into init :+ last. + * @return Some((init, last)) if sequence is non-empty. None otherwise. + */ + def unapply[A, CC[_] <: Seq[_], C <: SeqOps[A, CC, C]](t: C with SeqOps[A, CC, C]): Option[(C, A)] = + if(t.isEmpty) None + else Some(t.init -> t.last) + } +} From b899f8db9e8bb9d2f924ba95310ec959d32b0f08 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 10:11:31 +0100 Subject: [PATCH 63/89] Add immutable ArraySeq to stdlib --- .../collection/immutable/ArraySeq.scala | 692 ++++++++++++++++++ 1 file changed, 692 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/ArraySeq.scala diff --git a/tests/pos-special/stdlib/collection/immutable/ArraySeq.scala b/tests/pos-special/stdlib/collection/immutable/ArraySeq.scala new file mode 100644 index 000000000000..3a221fc76b6c --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/ArraySeq.scala @@ -0,0 +1,692 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package immutable + +import java.util.Arrays + +import scala.annotation.unchecked.uncheckedVariance +import scala.collection.Stepper.EfficientSplit +import scala.collection.mutable.{ArrayBuffer, ArrayBuilder, Builder, ArraySeq => MutableArraySeq} +import scala.collection.convert.impl._ +import scala.reflect.ClassTag +import scala.runtime.ScalaRunTime +import scala.util.Sorting +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** + * An immutable array. + * + * Supports efficient indexed access and has a small memory footprint. + * + * @define coll immutable array + * @define Coll `ArraySeq` + */ +sealed abstract class ArraySeq[+A] + extends AbstractSeq[A] + with IndexedSeq[A] + with IndexedSeqOps[A, ArraySeq, ArraySeq[A]] + with StrictOptimizedSeqOps[A, ArraySeq, ArraySeq[A]] + with EvidenceIterableFactoryDefaults[A, ArraySeq, ClassTag] + with Serializable + with Pure { + + /** The tag of the element type. This does not have to be equal to the element type of this ArraySeq. A primitive + * ArraySeq can be backed by an array of boxed values and a reference ArraySeq can be backed by an array of a supertype + * or subtype of the element type. */ + protected def elemTag: ClassTag[_] + + override def iterableFactory: SeqFactory[ArraySeq] = ArraySeq.untagged + + /** The wrapped mutable `Array` that backs this `ArraySeq`. Any changes to this array will break + * the expected immutability. Its element type does not have to be equal to the element type of this ArraySeq. + * A primitive ArraySeq can be backed by an array of boxed values and a reference ArraySeq can be backed by an + * array of a supertype or subtype of the element type. */ + def unsafeArray: Array[_] + + def unsafeArrayAsAnyArray = unsafeArray.asInstanceOf[Array[Any]] + + protected def evidenceIterableFactory: ArraySeq.type = ArraySeq + protected def iterableEvidence: ClassTag[A @uncheckedVariance @uncheckedCaptures] = elemTag.asInstanceOf[ClassTag[A]] + + def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit + + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): A + + override def updated[B >: A](index: Int, elem: B): ArraySeq[B] = { + val dest = new Array[Any](length) + Array.copy(unsafeArray, 0, dest, 0, length) + dest(index) = elem + ArraySeq.unsafeWrapArray(dest).asInstanceOf[ArraySeq[B]] + } + + override def map[B](f: A => B): ArraySeq[B] = { + val a = new Array[Any](size) + var i = 0 + while (i < a.length){ + a(i) = f(apply(i)) + i += 1 + } + ArraySeq.unsafeWrapArray(a).asInstanceOf[ArraySeq[B]] + } + + override def prepended[B >: A](elem: B): ArraySeq[B] = + ArraySeq.unsafeWrapArray(unsafeArrayAsAnyArray.prepended(elem)).asInstanceOf[ArraySeq[B]] + + override def appended[B >: A](elem: B): ArraySeq[B] = + ArraySeq.unsafeWrapArray(unsafeArrayAsAnyArray.appended[Any](elem)).asInstanceOf[ArraySeq[B]] + + /** Fast concatenation of two [[ArraySeq]]s. + * + * @return null if optimisation not possible. + */ + private def appendedAllArraySeq[B >: A](that: ArraySeq[B]): ArraySeq[B] = { + // Optimise concatenation of two ArraySeqs + // For ArraySeqs with sizes of [100, 1000, 10000] this is [3.5, 4.1, 5.2]x as fast + if (isEmpty) + that + else if (that.isEmpty) + this + else { + val thisIsObj = this.unsafeArray.isInstanceOf[Array[AnyRef]] + val thatIsObj = that.unsafeArray.isInstanceOf[Array[AnyRef]] + val mismatch = thisIsObj != thatIsObj + if (mismatch) + // Combining primatives and objects: abort + null + else if (thisIsObj) { + // A and B are objects + val ax = this.unsafeArray.asInstanceOf[Array[A @uncheckedCaptures]] + val ay = that.unsafeArray.asInstanceOf[Array[B @uncheckedCaptures]] + val len = ax.length + ay.length + val a = new Array[AnyRef](len) + System.arraycopy(ax, 0, a, 0, ax.length) + System.arraycopy(ay, 0, a, ax.length, ay.length) + ArraySeq.unsafeWrapArray(a).asInstanceOf[ArraySeq[B]] + } else { + // A is a primative and B = A. Use this instance's protected ClassTag. + val ax = this.unsafeArray.asInstanceOf[Array[A @uncheckedCaptures]] + val ay = that.unsafeArray.asInstanceOf[Array[A @uncheckedCaptures]] + val len = ax.length + ay.length + val a = iterableEvidence.newArray(len) + System.arraycopy(ax, 0, a, 0, ax.length) + System.arraycopy(ay, 0, a, ax.length, ay.length) + ArraySeq.unsafeWrapArray(a).asInstanceOf[ArraySeq[B]] + } + } + } + + override def appendedAll[B >: A](suffix: collection.IterableOnce[B]^): ArraySeq[B] = { + def genericResult = { + val k = suffix.knownSize + if (k == 0) this + else { + val b = ArrayBuilder.make[Any] + if(k >= 0) b.sizeHint(k + unsafeArray.length) + b.addAll(unsafeArray) + b.addAll(suffix) + ArraySeq.unsafeWrapArray(b.result()).asInstanceOf[ArraySeq[B]] + } + } + + suffix match { + case that: ArraySeq[_] => + val result = appendedAllArraySeq(that.asInstanceOf[ArraySeq[B]]) + if (result == null) genericResult + else result + case _ => + genericResult + } + } + + override def prependedAll[B >: A](prefix: collection.IterableOnce[B]^): ArraySeq[B] = { + def genericResult = { + val k = prefix.knownSize + if (k == 0) this + else { + val b = ArrayBuilder.make[Any] + if(k >= 0) b.sizeHint(k + unsafeArray.length) + b.addAll(prefix) + if(k < 0) b.sizeHint(b.length + unsafeArray.length) + b.addAll(unsafeArray) + ArraySeq.unsafeWrapArray(b.result()).asInstanceOf[ArraySeq[B]] + } + } + + prefix match { + case that: ArraySeq[_] => + val result = that.asInstanceOf[ArraySeq[B]].appendedAllArraySeq(this) + if (result == null) genericResult + else result + case _ => + genericResult + } + } + + override def zip[B](that: collection.IterableOnce[B]^): ArraySeq[(A, B)] = + that match { + case bs: ArraySeq[B] => + ArraySeq.tabulate(length min bs.length) { i => + (apply(i), bs(i)) + } + case _ => + strictOptimizedZip[B, ArraySeq[(A, B)]](that, iterableFactory.newBuilder) + } + + private inline def ops[A](xs: Array[A @uncheckedCaptures]): ArrayOps[A] = new ArrayOps[A @uncheckedCaptures](xs) + + override def take(n: Int): ArraySeq[A] = + if (unsafeArray.length <= n) + this + else + ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).take(n)).asInstanceOf[ArraySeq[A]] + + override def takeRight(n: Int): ArraySeq[A] = + if (unsafeArray.length <= n) + this + else + ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).takeRight(n)).asInstanceOf[ArraySeq[A]] + + override def drop(n: Int): ArraySeq[A] = + if (n <= 0) + this + else + ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).drop(n)).asInstanceOf[ArraySeq[A]] + + override def dropRight(n: Int): ArraySeq[A] = + if (n <= 0) + this + else + ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).dropRight(n)).asInstanceOf[ArraySeq[A]] + + override def slice(from: Int, until: Int): ArraySeq[A] = + if (from <= 0 && unsafeArray.length <= until) + this + else + ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).slice(from, until)).asInstanceOf[ArraySeq[A]] + + override def foldLeft[B](z: B)(f: (B, A) => B): B = { + // For ArraySeqs with sizes of [100, 1000, 10000] this is [1.3, 1.8, 1.8]x as fast + // as the same while-loop over this instead of unsafeArray. + val array = unsafeArray + var b = z + var i = 0 + while (i < array.length) { + val a = array(i).asInstanceOf[A] + b = f(b, a) + i += 1 + } + b + } + + override def foldRight[B](z: B)(f: (A, B) => B): B = { + // For ArraySeqs with sizes of [100, 1000, 10000] this is [1.6, 1.8, 2.7]x as fast + // as the same while-loop over this instead of unsafeArray. + val array = unsafeArray + var b = z + var i = array.length + while (i > 0) { + i -= 1 + val a = array(i).asInstanceOf[A] + b = f(a, b) + } + b + } + + override def tail: ArraySeq[A] = ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).tail).asInstanceOf[ArraySeq[A]] + + override def reverse: ArraySeq[A] = ArraySeq.unsafeWrapArray(ops(unsafeArrayAsAnyArray).reverse).asInstanceOf[ArraySeq[A]] + + override protected[this] def className = "ArraySeq" + + override def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = { + val copied = IterableOnce.elemsToCopyToArray(length, xs.length, start, len) + if(copied > 0) { + Array.copy(unsafeArray, 0, xs, start, copied) + } + copied + } + + override protected final def applyPreferredMaxLength: Int = Int.MaxValue + + override def sorted[B >: A](implicit ord: Ordering[B]): ArraySeq[A] = + if(unsafeArray.length <= 1) this + else { + val a = Array.copyAs[AnyRef](unsafeArray, length)(ClassTag.AnyRef) + Arrays.sort(a, ord.asInstanceOf[Ordering[AnyRef]]) + new ArraySeq.ofRef[AnyRef](a).asInstanceOf[ArraySeq[A]] + } +} + +/** + * $factoryInfo + * @define coll immutable array + * @define Coll `ArraySeq` + */ +@SerialVersionUID(3L) +object ArraySeq extends StrictOptimizedClassTagSeqFactory[ArraySeq] { self => + val untagged: SeqFactory[ArraySeq] = new ClassTagSeqFactory.AnySeqDelegate(self) + + private[this] lazy val emptyImpl = new ArraySeq.ofRef[Nothing](new Array[Nothing](0)) + + def empty[A : ClassTag]: ArraySeq[A] = emptyImpl + + def from[A](it: scala.collection.IterableOnce[A]^)(implicit tag: ClassTag[A]): ArraySeq[A] = it match { + case as: ArraySeq[A] => as + case _ => unsafeWrapArray(Array.from[A](it)) + } + + def newBuilder[A : ClassTag]: Builder[A, ArraySeq[A]] = + ArrayBuffer.newBuilder[A @uncheckedCaptures].mapResult(b => unsafeWrapArray[A](b.toArray)) + + override def fill[A : ClassTag](n: Int)(elem: => A): ArraySeq[A] = tabulate(n)(_ => elem) + + override def tabulate[A : ClassTag](n: Int)(f: Int => A): ArraySeq[A] = { + val elements = Array.ofDim[A @uncheckedCaptures](scala.math.max(n, 0)) + var i = 0 + while (i < n) { + ScalaRunTime.array_update(elements, i, f(i)) + i = i + 1 + } + ArraySeq.unsafeWrapArray(elements) + } + + /** + * Wrap an existing `Array` into an `ArraySeq` of the proper primitive specialization type + * without copying. Any changes to wrapped array will break the expected immutability. + * + * Note that an array containing boxed primitives can be wrapped in an `ArraySeq` without + * copying. For example, `val a: Array[Any] = Array(1)` is an array of `Object` at runtime, + * containing `Integer`s. An `ArraySeq[Int]` can be obtained with a cast: + * `ArraySeq.unsafeWrapArray(a).asInstanceOf[ArraySeq[Int]]`. The values are still + * boxed, the resulting instance is an [[ArraySeq.ofRef]]. Writing + * `ArraySeq.unsafeWrapArray(a.asInstanceOf[Array[Int]])` does not work, it throws a + * `ClassCastException` at runtime. + */ + def unsafeWrapArray[T](x: Array[T @uncheckedCaptures]): ArraySeq[T] = ((x: @unchecked) match { + case null => null + case x: Array[AnyRef] => new ofRef[AnyRef](x) + case x: Array[Int] => new ofInt(x) + case x: Array[Double] => new ofDouble(x) + case x: Array[Long] => new ofLong(x) + case x: Array[Float] => new ofFloat(x) + case x: Array[Char] => new ofChar(x) + case x: Array[Byte] => new ofByte(x) + case x: Array[Short] => new ofShort(x) + case x: Array[Boolean] => new ofBoolean(x) + case x: Array[Unit] => new ofUnit(x) + }).asInstanceOf[ArraySeq[T]] + + @SerialVersionUID(3L) + final class ofRef[T <: AnyRef](val unsafeArray: Array[T]) extends ArraySeq[T] { + def elemTag = ClassTag[T](unsafeArray.getClass.getComponentType) + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): T = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any): Boolean = that match { + case that: ofRef[_] => + Array.equals( + this.unsafeArray.asInstanceOf[Array[AnyRef]], + that.unsafeArray.asInstanceOf[Array[AnyRef]]) + case _ => super.equals(that) + } + override def sorted[B >: T](implicit ord: Ordering[B]): ArraySeq.ofRef[T] = { + if(unsafeArray.length <= 1) this + else { + val a = unsafeArray.clone() + Arrays.sort(a, ord.asInstanceOf[Ordering[T]]) + new ArraySeq.ofRef(a) + } + } + override def iterator: Iterator[T] = new ArrayOps.ArrayIterator[T](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[T, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + new ObjectArrayStepper(unsafeArray, 0, unsafeArray.length) + else shape.parUnbox(new ObjectArrayStepper(unsafeArray, 0, unsafeArray.length).asInstanceOf[AnyStepper[T] with EfficientSplit]) + ).asInstanceOf[S with EfficientSplit] + } + + @SerialVersionUID(3L) + final class ofByte(val unsafeArray: Array[Byte]) extends ArraySeq[Byte] { + protected def elemTag = ClassTag.Byte + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Byte = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofByte => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def sorted[B >: Byte](implicit ord: Ordering[B]): ArraySeq[Byte] = + if(length <= 1) this + else if(ord eq Ordering.Byte) { + val a = unsafeArray.clone() + Arrays.sort(a) + new ArraySeq.ofByte(a) + } else super.sorted[B] + override def iterator: Iterator[Byte] = new ArrayOps.ArrayIterator[Byte](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Byte, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new WidenedByteArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new WidenedByteArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Byte](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Byte => new ArraySeq.ofByte(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Byte](elem: B): ArraySeq[B] = + elem match { + case b: Byte => new ArraySeq.ofByte(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Byte](elem: B): ArraySeq[B] = + elem match { + case b: Byte => new ArraySeq.ofByte(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofShort(val unsafeArray: Array[Short]) extends ArraySeq[Short] { + protected def elemTag = ClassTag.Short + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Short = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofShort => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def sorted[B >: Short](implicit ord: Ordering[B]): ArraySeq[Short] = + if(length <= 1) this + else if(ord eq Ordering.Short) { + val a = unsafeArray.clone() + Arrays.sort(a) + new ArraySeq.ofShort(a) + } else super.sorted[B] + override def iterator: Iterator[Short] = new ArrayOps.ArrayIterator[Short](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Short, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new WidenedShortArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new WidenedShortArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Short](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Short => new ArraySeq.ofShort(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Short](elem: B): ArraySeq[B] = + elem match { + case b: Short => new ArraySeq.ofShort(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Short](elem: B): ArraySeq[B] = + elem match { + case b: Short => new ArraySeq.ofShort(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofChar(val unsafeArray: Array[Char]) extends ArraySeq[Char] { + protected def elemTag = ClassTag.Char + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Char = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofChar => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def sorted[B >: Char](implicit ord: Ordering[B]): ArraySeq[Char] = + if(length <= 1) this + else if(ord eq Ordering.Char) { + val a = unsafeArray.clone() + Arrays.sort(a) + new ArraySeq.ofChar(a) + } else super.sorted[B] + override def iterator: Iterator[Char] = new ArrayOps.ArrayIterator[Char](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Char, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new WidenedCharArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new WidenedCharArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Char](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Char => new ArraySeq.ofChar(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Char](elem: B): ArraySeq[B] = + elem match { + case b: Char => new ArraySeq.ofChar(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Char](elem: B): ArraySeq[B] = + elem match { + case b: Char => new ArraySeq.ofChar(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + + override def addString(sb: StringBuilder, start: String, sep: String, end: String): sb.type = + (new MutableArraySeq.ofChar(unsafeArray)).addString(sb, start, sep, end) + } + + @SerialVersionUID(3L) + final class ofInt(val unsafeArray: Array[Int]) extends ArraySeq[Int] { + protected def elemTag = ClassTag.Int + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Int = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofInt => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def sorted[B >: Int](implicit ord: Ordering[B]): ArraySeq[Int] = + if(length <= 1) this + else if(ord eq Ordering.Int) { + val a = unsafeArray.clone() + Arrays.sort(a) + new ArraySeq.ofInt(a) + } else super.sorted[B] + override def iterator: Iterator[Int] = new ArrayOps.ArrayIterator[Int](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Int, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParIntStepper(new IntArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new IntArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Int](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Int => new ArraySeq.ofInt(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Int](elem: B): ArraySeq[B] = + elem match { + case b: Int => new ArraySeq.ofInt(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Int](elem: B): ArraySeq[B] = + elem match { + case b: Int => new ArraySeq.ofInt(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofLong(val unsafeArray: Array[Long]) extends ArraySeq[Long] { + protected def elemTag = ClassTag.Long + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Long = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofLong => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def sorted[B >: Long](implicit ord: Ordering[B]): ArraySeq[Long] = + if(length <= 1) this + else if(ord eq Ordering.Long) { + val a = unsafeArray.clone() + Arrays.sort(a) + new ArraySeq.ofLong(a) + } else super.sorted[B] + override def iterator: Iterator[Long] = new ArrayOps.ArrayIterator[Long](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Long, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParLongStepper(new LongArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new LongArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Long](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Long => new ArraySeq.ofLong(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Long](elem: B): ArraySeq[B] = + elem match { + case b: Long => new ArraySeq.ofLong(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Long](elem: B): ArraySeq[B] = + elem match { + case b: Long => new ArraySeq.ofLong(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofFloat(val unsafeArray: Array[Float]) extends ArraySeq[Float] { + protected def elemTag = ClassTag.Float + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Float = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofFloat => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def iterator: Iterator[Float] = new ArrayOps.ArrayIterator[Float](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Float, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParDoubleStepper(new WidenedFloatArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new WidenedFloatArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Float](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Float => new ArraySeq.ofFloat(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Float](elem: B): ArraySeq[B] = + elem match { + case b: Float => new ArraySeq.ofFloat(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Float](elem: B): ArraySeq[B] = + elem match { + case b: Float => new ArraySeq.ofFloat(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofDouble(val unsafeArray: Array[Double]) extends ArraySeq[Double] { + protected def elemTag = ClassTag.Double + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Double = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofDouble => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def iterator: Iterator[Double] = new ArrayOps.ArrayIterator[Double](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Double, S]): S with EfficientSplit = ( + if(shape.shape == StepperShape.ReferenceShape) + AnyStepper.ofParDoubleStepper(new DoubleArrayStepper(unsafeArray, 0, unsafeArray.length)) + else new DoubleArrayStepper(unsafeArray, 0, unsafeArray.length) + ).asInstanceOf[S with EfficientSplit] + override def updated[B >: Double](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Double => new ArraySeq.ofDouble(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Double](elem: B): ArraySeq[B] = + elem match { + case b: Double => new ArraySeq.ofDouble(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Double](elem: B): ArraySeq[B] = + elem match { + case b: Double => new ArraySeq.ofDouble(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofBoolean(val unsafeArray: Array[Boolean]) extends ArraySeq[Boolean] { + protected def elemTag = ClassTag.Boolean + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Boolean = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofBoolean => Arrays.equals(unsafeArray, that.unsafeArray) + case _ => super.equals(that) + } + override def sorted[B >: Boolean](implicit ord: Ordering[B]): ArraySeq[Boolean] = + if(length <= 1) this + else if(ord eq Ordering.Boolean) { + val a = unsafeArray.clone() + Sorting.stableSort(a) + new ArraySeq.ofBoolean(a) + } else super.sorted[B] + override def iterator: Iterator[Boolean] = new ArrayOps.ArrayIterator[Boolean](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Boolean, S]): S with EfficientSplit = + new BoxedBooleanArrayStepper(unsafeArray, 0, unsafeArray.length).asInstanceOf[S with EfficientSplit] + override def updated[B >: Boolean](index: Int, elem: B): ArraySeq[B] = + elem match { + case b: Boolean => new ArraySeq.ofBoolean(unsafeArray.updated(index, b)) + case _ => super.updated(index, elem) + } + override def appended[B >: Boolean](elem: B): ArraySeq[B] = + elem match { + case b: Boolean => new ArraySeq.ofBoolean(unsafeArray.appended(b)) + case _ => super.appended(elem) + } + override def prepended[B >: Boolean](elem: B): ArraySeq[B] = + elem match { + case b: Boolean => new ArraySeq.ofBoolean(unsafeArray.prepended(b)) + case _ => super.prepended(elem) + } + } + + @SerialVersionUID(3L) + final class ofUnit(val unsafeArray: Array[Unit]) extends ArraySeq[Unit] { + protected def elemTag = ClassTag.Unit + def length: Int = unsafeArray.length + @throws[ArrayIndexOutOfBoundsException] + def apply(i: Int): Unit = unsafeArray(i) + override def hashCode = MurmurHash3.arraySeqHash(unsafeArray) + override def equals(that: Any) = that match { + case that: ofUnit => unsafeArray.length == that.unsafeArray.length + case _ => super.equals(that) + } + override def iterator: Iterator[Unit] = new ArrayOps.ArrayIterator[Unit](unsafeArray) + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Unit, S]): S with EfficientSplit = + new ObjectArrayStepper[AnyRef](unsafeArray.asInstanceOf[Array[AnyRef]], 0, unsafeArray.length).asInstanceOf[S with EfficientSplit] + } +} From 1f3fe9eb930f53f01c818b1bfe2ab02dcb0ed554 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 10:32:23 +0100 Subject: [PATCH 64/89] Add immutable HashSet and HashMap to stdlib --- .../collection/immutable/ChampCommon.scala | 253 ++ .../stdlib/collection/immutable/HashMap.scala | 2425 +++++++++++++++++ .../stdlib/collection/immutable/HashSet.scala | 2125 +++++++++++++++ 3 files changed, 4803 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/ChampCommon.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/HashMap.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/HashSet.scala diff --git a/tests/pos-special/stdlib/collection/immutable/ChampCommon.scala b/tests/pos-special/stdlib/collection/immutable/ChampCommon.scala new file mode 100644 index 000000000000..fc9bcb022874 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/ChampCommon.scala @@ -0,0 +1,253 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.immutable + + +import java.lang.Integer.bitCount +import java.lang.Math.ceil +import java.lang.System.arraycopy +import language.experimental.captureChecking + +private[collection] object Node { + final val HashCodeLength = 32 + + final val BitPartitionSize = 5 + + final val BitPartitionMask = (1 << BitPartitionSize) - 1 + + final val MaxDepth = ceil(HashCodeLength.toDouble / BitPartitionSize).toInt + + final val BranchingFactor = 1 << BitPartitionSize + + final def maskFrom(hash: Int, shift: Int): Int = (hash >>> shift) & BitPartitionMask + + final def bitposFrom(mask: Int): Int = 1 << mask + + final def indexFrom(bitmap: Int, bitpos: Int): Int = bitCount(bitmap & (bitpos - 1)) + + final def indexFrom(bitmap: Int, mask: Int, bitpos: Int): Int = if (bitmap == -1) mask else indexFrom(bitmap, bitpos) + +} + +private[collection] abstract class Node[T <: Node[T]] { + + def hasNodes: Boolean + + def nodeArity: Int + + def getNode(index: Int): T + + def hasPayload: Boolean + + def payloadArity: Int + + def getPayload(index: Int): Any + + def getHash(index: Int): Int + + def cachedJavaKeySetHashCode: Int + + private final def arrayIndexOutOfBounds(as: Array[_], ix:Int): ArrayIndexOutOfBoundsException = + new ArrayIndexOutOfBoundsException(s"$ix is out of bounds (min 0, max ${as.length-1}") + + protected final def removeElement(as: Array[Int], ix: Int): Array[Int] = { + if (ix < 0) throw arrayIndexOutOfBounds(as, ix) + if (ix > as.length - 1) throw arrayIndexOutOfBounds(as, ix) + val result = new Array[Int](as.length - 1) + arraycopy(as, 0, result, 0, ix) + arraycopy(as, ix + 1, result, ix, as.length - ix - 1) + result + } + + protected final def removeAnyElement(as: Array[Any], ix: Int): Array[Any] = { + if (ix < 0) throw arrayIndexOutOfBounds(as, ix) + if (ix > as.length - 1) throw arrayIndexOutOfBounds(as, ix) + val result = new Array[Any](as.length - 1) + arraycopy(as, 0, result, 0, ix) + arraycopy(as, ix + 1, result, ix, as.length - ix - 1) + result + } + + protected final def insertElement(as: Array[Int], ix: Int, elem: Int): Array[Int] = { + if (ix < 0) throw arrayIndexOutOfBounds(as, ix) + if (ix > as.length) throw arrayIndexOutOfBounds(as, ix) + val result = new Array[Int](as.length + 1) + arraycopy(as, 0, result, 0, ix) + result(ix) = elem + arraycopy(as, ix, result, ix + 1, as.length - ix) + result + } + protected final def insertAnyElement(as: Array[Any], ix: Int, elem: Int): Array[Any] = { + if (ix < 0) throw arrayIndexOutOfBounds(as, ix) + if (ix > as.length) throw arrayIndexOutOfBounds(as, ix) + val result = new Array[Any](as.length + 1) + arraycopy(as, 0, result, 0, ix) + result(ix) = elem + arraycopy(as, ix, result, ix + 1, as.length - ix) + result + } +} + +/** + * Base class for fixed-stack iterators that traverse a hash-trie. The iterator performs a + * depth-first pre-order traversal, which yields first all payload elements of the current + * node before traversing sub-nodes (left to right). + * + * @tparam T the trie node type we are iterating over + */ +private[immutable] abstract class ChampBaseIterator[T <: Node[T]] { + + import Node.MaxDepth + + // Note--this code is duplicated to a large extent both in + // ChampBaseReverseIterator and in convert.impl.ChampStepperBase. + // If you change this code, check those also in case they also + // need to be modified. + + protected var currentValueCursor: Int = 0 + protected var currentValueLength: Int = 0 + protected var currentValueNode: T = _ + + private[this] var currentStackLevel: Int = -1 + private[this] var nodeCursorsAndLengths: Array[Int] = _ + private[this] var nodes: Array[T] = _ + private def initNodes(): Unit = { + if (nodeCursorsAndLengths eq null) { + nodeCursorsAndLengths = new Array[Int](MaxDepth * 2) + nodes = new Array[Node[T]](MaxDepth).asInstanceOf[Array[T]] + } + } + + def this(rootNode: T) = { + this() + if (rootNode.hasNodes) pushNode(rootNode) + if (rootNode.hasPayload) setupPayloadNode(rootNode) + } + + private final def setupPayloadNode(node: T): Unit = { + currentValueNode = node + currentValueCursor = 0 + currentValueLength = node.payloadArity + } + + private final def pushNode(node: T): Unit = { + initNodes() + currentStackLevel = currentStackLevel + 1 + + val cursorIndex = currentStackLevel * 2 + val lengthIndex = currentStackLevel * 2 + 1 + + nodes(currentStackLevel) = node + nodeCursorsAndLengths(cursorIndex) = 0 + nodeCursorsAndLengths(lengthIndex) = node.nodeArity + } + + private final def popNode(): Unit = { + currentStackLevel = currentStackLevel - 1 + } + + /** + * Searches for next node that contains payload values, + * and pushes encountered sub-nodes on a stack for depth-first traversal. + */ + private final def searchNextValueNode(): Boolean = { + while (currentStackLevel >= 0) { + val cursorIndex = currentStackLevel * 2 + val lengthIndex = currentStackLevel * 2 + 1 + + val nodeCursor = nodeCursorsAndLengths(cursorIndex) + val nodeLength = nodeCursorsAndLengths(lengthIndex) + + if (nodeCursor < nodeLength) { + nodeCursorsAndLengths(cursorIndex) += 1 + + val nextNode = nodes(currentStackLevel).getNode(nodeCursor) + + if (nextNode.hasNodes) { pushNode(nextNode) } + if (nextNode.hasPayload) { setupPayloadNode(nextNode) ; return true } + } else { + popNode() + } + } + + return false + } + + final def hasNext = (currentValueCursor < currentValueLength) || searchNextValueNode() + +} + +/** + * Base class for fixed-stack iterators that traverse a hash-trie in reverse order. The base + * iterator performs a depth-first post-order traversal, traversing sub-nodes (right to left). + * + * @tparam T the trie node type we are iterating over + */ +private[immutable] abstract class ChampBaseReverseIterator[T <: Node[T]] { + + import Node.MaxDepth + + protected var currentValueCursor: Int = -1 + protected var currentValueNode: T = _ + + private[this] var currentStackLevel: Int = -1 + private[this] val nodeIndex: Array[Int] = new Array[Int](MaxDepth + 1) + private[this] val nodeStack: Array[T] = new Array[Node[T]](MaxDepth + 1).asInstanceOf[Array[T]] + + def this(rootNode: T) = { + this() + pushNode(rootNode) + searchNextValueNode() + } + + private final def setupPayloadNode(node: T): Unit = { + currentValueNode = node + currentValueCursor = node.payloadArity - 1 + } + + private final def pushNode(node: T): Unit = { + currentStackLevel = currentStackLevel + 1 + + nodeStack(currentStackLevel) = node + nodeIndex(currentStackLevel) = node.nodeArity - 1 + } + + private final def popNode(): Unit = { + currentStackLevel = currentStackLevel - 1 + } + + /** + * Searches for rightmost node that contains payload values, + * and pushes encountered sub-nodes on a stack for depth-first traversal. + */ + private final def searchNextValueNode(): Boolean = { + while (currentStackLevel >= 0) { + val nodeCursor = nodeIndex(currentStackLevel) ; nodeIndex(currentStackLevel) = nodeCursor - 1 + + if (nodeCursor >= 0) { + val nextNode = nodeStack(currentStackLevel).getNode(nodeCursor) + pushNode(nextNode) + } else { + val currNode = nodeStack(currentStackLevel) + popNode() + + if (currNode.hasPayload) { setupPayloadNode(currNode) ; return true } + } + } + + return false + } + + final def hasNext = (currentValueCursor >= 0) || searchNextValueNode() + +} diff --git a/tests/pos-special/stdlib/collection/immutable/HashMap.scala b/tests/pos-special/stdlib/collection/immutable/HashMap.scala new file mode 100644 index 000000000000..d2f144baa934 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/HashMap.scala @@ -0,0 +1,2425 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.immutable + +import java.lang.Integer.bitCount +import java.lang.System.arraycopy + +import scala.annotation.unchecked.{uncheckedVariance => uV} +import scala.collection.Hashing.improve +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.mutable, mutable.ReusableBuilder +import scala.collection.{Iterator, MapFactory, MapFactoryDefaults, Stepper, StepperShape, mutable} +import scala.runtime.AbstractFunction2 +import scala.runtime.Statics.releaseFence +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** This class implements immutable maps using a Compressed Hash-Array Mapped Prefix-tree. + * See paper https://michael.steindorfer.name/publications/oopsla15.pdf for more details. + * + * @tparam K the type of the keys contained in this hash set. + * @tparam V the type of the values associated with the keys in this hash map. + * + * @define Coll `immutable.HashMap` + * @define coll immutable champ hash map + */ + +final class HashMap[K, +V] private[immutable] (private[immutable] val rootNode: BitmapIndexedMapNode[K, V]) + extends AbstractMap[K, V] + with StrictOptimizedMapOps[K, V, HashMap, HashMap[K, V]] + with MapFactoryDefaults[K, V, HashMap, Iterable] + with DefaultSerializable { + + def this() = this(MapNode.empty) + + // This release fence is present because rootNode may have previously been mutated during construction. + releaseFence() + + override def mapFactory: MapFactory[HashMap] = HashMap + + override def knownSize: Int = rootNode.size + + override def size: Int = rootNode.size + + override def isEmpty: Boolean = rootNode.size == 0 + + override def keySet: Set[K] = if (size == 0) Set.empty else new HashKeySet + + private final class HashKeySet extends ImmutableKeySet { + + private[this] def newKeySetOrThis(newHashMap: HashMap[K, _]): Set[K] = + if (newHashMap eq HashMap.this) this else newHashMap.keySet + private[this] def newKeySetOrThis(newRootNode: BitmapIndexedMapNode[K, _]): Set[K] = + if (newRootNode eq rootNode) this else new HashMap(newRootNode).keySet + + override def incl(elem: K): Set[K] = { + val originalHash = elem.## + val improvedHash = improve(originalHash) + val newNode = rootNode.updated(elem, null.asInstanceOf[V], originalHash, improvedHash, 0, replaceValue = false) + newKeySetOrThis(newNode) + } + override def excl(elem: K): Set[K] = newKeySetOrThis(HashMap.this - elem) + override def filter(pred: K => Boolean): Set[K] = newKeySetOrThis(HashMap.this.filter(kv => pred(kv._1))) + override def filterNot(pred: K => Boolean): Set[K] = newKeySetOrThis(HashMap.this.filterNot(kv => pred(kv._1))) + } + + def iterator: Iterator[(K, V)] = { + if (isEmpty) Iterator.empty + else new MapKeyValueTupleIterator[K, V](rootNode) + } + + override def keysIterator: Iterator[K] = { + if (isEmpty) Iterator.empty + else new MapKeyIterator[K, V](rootNode) + } + override def valuesIterator: Iterator[V] = { + if (isEmpty) Iterator.empty + else new MapValueIterator[K, V](rootNode) + } + + protected[immutable] def reverseIterator: Iterator[(K, V)] = { + if (isEmpty) Iterator.empty + else new MapKeyValueTupleReverseIterator[K, V](rootNode) + } + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[(K, V), S]): S with EfficientSplit = + shape. + parUnbox(collection.convert.impl.AnyChampStepper.from[(K, V), MapNode[K, V]](size, rootNode, (node, i) => node.getPayload(i))) + + override def keyStepper[S <: Stepper[_]](implicit shape: StepperShape[K, S]): S with EfficientSplit = { + import collection.convert.impl._ + val s = shape.shape match { + case StepperShape.IntShape => IntChampStepper.from[ MapNode[K, V]](size, rootNode, (node, i) => node.getKey(i).asInstanceOf[Int]) + case StepperShape.LongShape => LongChampStepper.from[ MapNode[K, V]](size, rootNode, (node, i) => node.getKey(i).asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleChampStepper.from[MapNode[K, V]](size, rootNode, (node, i) => node.getKey(i).asInstanceOf[Double]) + case _ => shape.parUnbox(AnyChampStepper.from[K, MapNode[K, V]](size, rootNode, (node, i) => node.getKey(i))) + } + s.asInstanceOf[S with EfficientSplit] + } + + override def valueStepper[S <: Stepper[_]](implicit shape: StepperShape[V, S]): S with EfficientSplit = { + import collection.convert.impl._ + val s = shape.shape match { + case StepperShape.IntShape => IntChampStepper.from[ MapNode[K, V]](size, rootNode, (node, i) => node.getValue(i).asInstanceOf[Int]) + case StepperShape.LongShape => LongChampStepper.from[ MapNode[K, V]](size, rootNode, (node, i) => node.getValue(i).asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleChampStepper.from[MapNode[K, V]](size, rootNode, (node, i) => node.getValue(i).asInstanceOf[Double]) + case _ => shape.parUnbox(AnyChampStepper.from[V, MapNode[K, V]](size, rootNode, (node, i) => node.getValue(i))) + } + s.asInstanceOf[S with EfficientSplit] + } + + override final def contains(key: K): Boolean = { + val keyUnimprovedHash = key.## + val keyHash = improve(keyUnimprovedHash) + rootNode.containsKey(key, keyUnimprovedHash, keyHash, 0) + } + + override def apply(key: K): V = { + val keyUnimprovedHash = key.## + val keyHash = improve(keyUnimprovedHash) + rootNode.apply(key, keyUnimprovedHash, keyHash, 0) + } + + def get(key: K): Option[V] = { + val keyUnimprovedHash = key.## + val keyHash = improve(keyUnimprovedHash) + rootNode.get(key, keyUnimprovedHash, keyHash, 0) + } + + override def getOrElse[V1 >: V](key: K, default: => V1): V1 = { + val keyUnimprovedHash = key.## + val keyHash = improve(keyUnimprovedHash) + rootNode.getOrElse(key, keyUnimprovedHash, keyHash, 0, default) + } + + @`inline` private[this] def newHashMapOrThis[V1 >: V](newRootNode: BitmapIndexedMapNode[K, V1]): HashMap[K, V1] = + if (newRootNode eq rootNode) this else new HashMap(newRootNode) + + def updated[V1 >: V](key: K, value: V1): HashMap[K, V1] = { + val keyUnimprovedHash = key.## + newHashMapOrThis(rootNode.updated(key, value, keyUnimprovedHash, improve(keyUnimprovedHash), 0, replaceValue = true)) + } + + // preemptively overridden in anticipation of performance optimizations + override def updatedWith[V1 >: V](key: K)(remappingFunction: Option[V] => Option[V1]): HashMap[K, V1] = + super.updatedWith[V1](key)(remappingFunction) + + def removed(key: K): HashMap[K, V] = { + val keyUnimprovedHash = key.## + newHashMapOrThis(rootNode.removed(key, keyUnimprovedHash, improve(keyUnimprovedHash), 0)) + } + + override def concat[V1 >: V](that: scala.IterableOnce[(K, V1)]^): HashMap[K, V1] = that match { + case hm: HashMap[K, V1] => + if (isEmpty) hm + else { + val newNode = rootNode.concat(hm.rootNode, 0) + if (newNode eq hm.rootNode) hm + else newHashMapOrThis(rootNode.concat(hm.rootNode, 0)) + } + case hm: mutable.HashMap[K @unchecked, V @unchecked] => + val iter = hm.nodeIterator + var current = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = hm.unimproveHash(next.hash) + val improved = improve(originalHash) + current = current.updated(next.key, next.value, originalHash, improved, 0, replaceValue = true) + + if (current ne rootNode) { + var shallowlyMutableNodeMap = Node.bitposFrom(Node.maskFrom(improved, 0)) + + while (iter.hasNext) { + val next = iter.next() + val originalHash = hm.unimproveHash(next.hash) + shallowlyMutableNodeMap = current.updateWithShallowMutations(next.key, next.value, originalHash, improve(originalHash), 0, shallowlyMutableNodeMap) + } + return new HashMap(current) + } + } + this + case lhm: mutable.LinkedHashMap[K @unchecked, V @unchecked] => + val iter = lhm.entryIterator + var current = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = lhm.unimproveHash(next.hash) + val improved = improve(originalHash) + current = current.updated(next.key, next.value, originalHash, improved, 0, replaceValue = true) + + if (current ne rootNode) { + var shallowlyMutableNodeMap = Node.bitposFrom(Node.maskFrom(improved, 0)) + + while (iter.hasNext) { + val next = iter.next() + val originalHash = lhm.unimproveHash(next.hash) + shallowlyMutableNodeMap = current.updateWithShallowMutations(next.key, next.value, originalHash, improve(originalHash), 0, shallowlyMutableNodeMap) + } + return new HashMap(current) + } + } + this + case _ => + class accum extends AbstractFunction2[K, V1, Unit] with Function1[(K, V1), Unit] { + var changed = false + var shallowlyMutableNodeMap: Int = 0 + var current: BitmapIndexedMapNode[K, V1] = rootNode + def apply(kv: (K, V1)) = apply(kv._1, kv._2) + def apply(key: K, value: V1): Unit = { + val originalHash = key.## + val improved = improve(originalHash) + if (!changed) { + current = current.updated(key, value, originalHash, improved, 0, replaceValue = true) + if (current ne rootNode) { + // Note: We could have started with shallowlyMutableNodeMap = 0, however this way, in the case that + // the first changed key ended up in a subnode beneath root, we mark that root right away as being + // shallowly mutable. + // + // since key->value has just been inserted, and certainly caused a new root node to be created, we can say with + // certainty that it either caused a new subnode to be created underneath `current`, in which case we should + // carry on mutating that subnode, or it ended up as a child data pair of the root, in which case, no harm is + // done by including its bit position in the shallowlyMutableNodeMap anyways. + changed = true + shallowlyMutableNodeMap = Node.bitposFrom(Node.maskFrom(improved, 0)) + } + } else { + shallowlyMutableNodeMap = current.updateWithShallowMutations(key, value, originalHash, improved, 0, shallowlyMutableNodeMap) + } + } + } + that match { + case thatMap: Map[K, V1] => + if (thatMap.isEmpty) this + else { + val accum = new accum + thatMap.foreachEntry(accum) + newHashMapOrThis(accum.current) + } + case _ => + val it = that.iterator + if (it.isEmpty) this + else { + val accum = new accum + it.foreach(accum) + newHashMapOrThis(accum.current) + } + } + } + + override def tail: HashMap[K, V] = this - head._1 + + override def init: HashMap[K, V] = this - last._1 + + override def head: (K, V) = iterator.next() + + override def last: (K, V) = reverseIterator.next() + + override def foreach[U](f: ((K, V)) => U): Unit = rootNode.foreach(f) + + override def foreachEntry[U](f: (K, V) => U): Unit = rootNode.foreachEntry(f) + + /** Applies a function to each key, value, and **original** hash value in this Map */ + @`inline` private[collection] def foreachWithHash(f: (K, V, Int) => Unit): Unit = rootNode.foreachWithHash(f) + + override def equals(that: Any): Boolean = + that match { + case map: HashMap[_, _] => (this eq map) || (this.rootNode == map.rootNode) + case _ => super.equals(that) + } + + override def hashCode(): Int = { + if (isEmpty) MurmurHash3.emptyMapHash + else { + // Optimized to avoid recomputation of key hashcodes as these are cached in the nodes and can be assumed to be + // immutable. + val hashIterator = new MapKeyValueTupleHashIterator(rootNode) + val hash = MurmurHash3.unorderedHash(hashIterator, MurmurHash3.mapSeed) + // assert(hash == super.hashCode()) + hash + } + } + + override protected[this] def className = "HashMap" + + /** Merges this HashMap with an other HashMap by combining all key-value pairs of both maps, and delegating to a merge + * function to resolve any key collisions between the two HashMaps. + * + * @example {{{ + * val left = HashMap(1 -> 1, 2 -> 1) + * val right = HashMap(2 -> 2, 3 -> 2) + * + * val merged = left.merged(right){ case ((k0, v0), (k1, v1)) => (k0 + k1) -> (v0 + v1) } + * // HashMap(1 -> 1, 3 -> 2, 4 -> 3) + * + * }}} + * + * @param that the HashMap to merge this HashMap with + * @param mergef the merge function which resolves collisions between the two HashMaps. If `mergef` is null, then + * keys from `this` will overwrite keys from `that`, making the behaviour equivalent to + * `that.concat(this)` + * + * @note In cases where `mergef` returns keys which themselves collide with other keys returned by `merge`, or + * found in `this` or `that`, it is not defined which value will be chosen. For example: + * + * Colliding multiple results of merging: + * {{{ + * // key `3` collides between a result of merging keys `1` and `2` + * val left = HashMap(1 -> 1, 2 -> 2) + * val right = HashMap(1 -> 1, 2 -> 2) + * + * val merged = left.merged(right){ case (_, (_, v1)) => 3 -> v1 } + * // HashMap(3 -> 2) is returned, but it could also have returned HashMap(3 -> 1) + * }}} + * Colliding results of merging with other keys: + * {{{ + * // key `2` collides between a result of merging `1`, and existing key `2` + * val left = HashMap(1 -> 1, 2 -> 1) + * val right = HashMap(1 -> 2) + * + * val merged = left.merged(right)((_,_) => 2 -> 3) + * // HashMap(2 -> 1) is returned, but it could also have returned HashMap(2 -> 3) + * }}} + * + */ + def merged[V1 >: V](that: HashMap[K, V1])(mergef: ((K, V), (K, V1)) => (K, V1)): HashMap[K, V1] = + if (mergef == null) { + that ++ this + } else { + if (isEmpty) that + else if (that.isEmpty) this + else if (size == 1) { + val payload@(k, v) = rootNode.getPayload(0) + val originalHash = rootNode.getHash(0) + val improved = improve(originalHash) + + if (that.rootNode.containsKey(k, originalHash, improved, 0)) { + val thatPayload = that.rootNode.getTuple(k, originalHash, improved, 0) + val (mergedK, mergedV) = mergef(payload, thatPayload) + val mergedOriginalHash = mergedK.## + val mergedImprovedHash = improve(mergedOriginalHash) + new HashMap(that.rootNode.removed(thatPayload._1, originalHash, improved, 0).updated(mergedK, mergedV, mergedOriginalHash, mergedImprovedHash, 0, replaceValue = true)) + } else { + new HashMap(that.rootNode.updated(k, v, originalHash, improved, 0, replaceValue = true)) + } + } else if (that.size == 0) { + val thatPayload@(k, v) = rootNode.getPayload(0) + val thatOriginalHash = rootNode.getHash(0) + val thatImproved = improve(thatOriginalHash) + + if (rootNode.containsKey(k, thatOriginalHash, thatImproved, 0)) { + val payload = rootNode.getTuple(k, thatOriginalHash, thatImproved, 0) + val (mergedK, mergedV) = mergef(payload, thatPayload) + val mergedOriginalHash = mergedK.## + val mergedImprovedHash = improve(mergedOriginalHash) + new HashMap(rootNode.updated(mergedK, mergedV, mergedOriginalHash, mergedImprovedHash, 0, replaceValue = true)) + } else { + new HashMap(rootNode.updated(k, v, thatOriginalHash, thatImproved, 0, replaceValue = true)) + } + } else { + val builder = new HashMapBuilder[K, V1] + rootNode.mergeInto(that.rootNode, builder, 0)(mergef) + builder.result() + } + } + + override def transform[W](f: (K, V) => W): HashMap[K, W] = + newHashMapOrThis(rootNode.transform[Any](f)).asInstanceOf[HashMap[K, W]] + + override protected[collection] def filterImpl(pred: ((K, V)) => Boolean, isFlipped: Boolean): HashMap[K, V] = { + val newRootNode = rootNode.filterImpl(pred, isFlipped) + if (newRootNode eq rootNode) this + else if (newRootNode.size == 0) HashMap.empty + else new HashMap(newRootNode) + } + + override def removedAll(keys: IterableOnce[K]): HashMap[K, V] = { + if (isEmpty) { + this + } else { + keys match { + case hashSet: HashSet[K] => + if (hashSet.isEmpty) { + this + } else { + // TODO: Remove all keys from the hashSet in a sub-linear fashion by only visiting the nodes in the tree + // This can be a direct port of the implementation of `SetNode[A]#diff(SetNode[A])` + val newRootNode = new MapNodeRemoveAllSetNodeIterator(hashSet.rootNode).removeAll(rootNode) + if (newRootNode eq rootNode) this + else if (newRootNode.size <= 0) HashMap.empty + else new HashMap(newRootNode) + } + case hashSet: collection.mutable.HashSet[K] => + if (hashSet.isEmpty) { + this + } else { + val iter = hashSet.nodeIterator + var curr = rootNode + + while (iter.hasNext) { + val next = iter.next() + val originalHash = hashSet.unimproveHash(next.hash) + val improved = improve(originalHash) + curr = curr.removed(next.key, originalHash, improved, 0) + if (curr.size == 0) { + return HashMap.empty + } + } + newHashMapOrThis(curr) + } + case lhashSet: collection.mutable.LinkedHashSet[K] => + if (lhashSet.isEmpty) { + this + } else { + val iter = lhashSet.entryIterator + var curr = rootNode + + while (iter.hasNext) { + val next = iter.next() + val originalHash = lhashSet.unimproveHash(next.hash) + val improved = improve(originalHash) + curr = curr.removed(next.key, originalHash, improved, 0) + if (curr.size == 0) { + return HashMap.empty + } + } + newHashMapOrThis(curr) + } + case _ => + val iter = keys.iterator + var curr = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = next.## + val improved = improve(originalHash) + curr = curr.removed(next, originalHash, improved, 0) + if (curr.size == 0) { + return HashMap.empty + } + } + newHashMapOrThis(curr) + } + } + } + + override def partition(p: ((K, V)) => Boolean): (HashMap[K, V], HashMap[K, V]) = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `partition` could be optimized to traverse the trie node-by-node, splitting each node into two, + // based on the result of applying `p` to its elements and subnodes. + super.partition(p) + } + + override def take(n: Int): HashMap[K, V] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `take` could be optimized to construct a new trie structure by visiting each node, and including + // those nodes in the resulting trie, until `n` total elements have been included. + super.take(n) + } + + override def takeRight(n: Int): HashMap[K, V] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `take` could be optimized to construct a new trie structure by visiting each node in reverse, and + // and including those nodes in the resulting trie, until `n` total elements have been included. + super.takeRight(n) + } + + override def takeWhile(p: ((K, V)) => Boolean): HashMap[K, V] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `takeWhile` could be optimized to construct a new trie structure by visiting each node, and + // including those nodes in the resulting trie, until `p` returns `false` + super.takeWhile(p) + } + + override def dropWhile(p: ((K, V)) => Boolean): HashMap[K, V] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `dropWhile` could be optimized to construct a new trie structure by visiting each node, and + // dropping those nodes in the resulting trie, until `p` returns `true` + super.dropWhile(p) + } + + override def dropRight(n: Int): HashMap[K, V] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `dropRight` could be optimized to construct a new trie structure by visiting each node, in reverse + // order, and dropping all nodes until `n` elements have been dropped + super.dropRight(n) + } + + override def drop(n: Int): HashMap[K, V] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `dropRight` could be optimized to construct a new trie structure by visiting each node, and + // dropping all nodes until `n` elements have been dropped + super.drop(n) + } + + override def span(p: ((K, V)) => Boolean): (HashMap[K, V], HashMap[K, V]) = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + // + // In particular, `scan` could be optimized to construct a new trie structure by visiting each node, and + // keeping each node and element until `p` returns false, then including the remaining nodes in the second result. + // This would avoid having to rebuild most of the trie, and would eliminate the need to perform hashing and equality + // checks. + super.span(p) + } + +} + +private[immutable] object MapNode { + + private final val EmptyMapNode = new BitmapIndexedMapNode(0, 0, Array.empty, Array.empty, 0, 0) + + def empty[K, V]: BitmapIndexedMapNode[K, V] = EmptyMapNode.asInstanceOf[BitmapIndexedMapNode[K, V]] + + final val TupleLength = 2 + +} + + +private[immutable] sealed abstract class MapNode[K, +V] extends Node[MapNode[K, V @uV]] { + def apply(key: K, originalHash: Int, hash: Int, shift: Int): V + + def get(key: K, originalHash: Int, hash: Int, shift: Int): Option[V] + + def getOrElse[V1 >: V](key: K, originalHash: Int, hash: Int, shift: Int, f: => V1): V1 + + def containsKey(key: K, originalHash: Int, hash: Int, shift: Int): Boolean + + /** Returns a MapNode with the passed key-value assignment added + * + * @param key the key to add to the MapNode + * @param value the value to associate with `key` + * @param originalHash the original hash of `key` + * @param hash the improved hash of `key` + * @param shift the shift of the node (distanceFromRoot * BitPartitionSize) + * @param replaceValue if true, then the value currently associated to `key` will be replaced with the passed value + * argument. + * if false, then the key will be inserted if not already present, however if the key is present + * then the passed value will not replace the current value. That is, if `false`, then this + * method has `update if not exists` semantics. + */ + def updated[V1 >: V](key: K, value: V1, originalHash: Int, hash: Int, shift: Int, replaceValue: Boolean): MapNode[K, V1] + + def removed[V1 >: V](key: K, originalHash: Int, hash: Int, shift: Int): MapNode[K, V1] + + def hasNodes: Boolean + + def nodeArity: Int + + def getNode(index: Int): MapNode[K, V] + + def hasPayload: Boolean + + def payloadArity: Int + + def getKey(index: Int): K + + def getValue(index: Int): V + + def getPayload(index: Int): (K, V) + + def size: Int + + def foreach[U](f: ((K, V)) => U): Unit + + def foreachEntry[U](f: (K, V) => U): Unit + + def foreachWithHash(f: (K, V, Int) => Unit): Unit + + def transform[W](f: (K, V) => W): MapNode[K, W] + + def copy(): MapNode[K, V] + + def concat[V1 >: V](that: MapNode[K, V1], shift: Int): MapNode[K, V1] + + def filterImpl(pred: ((K, V)) => Boolean, isFlipped: Boolean): MapNode[K, V] + + /** Merges this node with that node, adding each resulting tuple to `builder` + * + * `this` should be a node from `left` hashmap in `left.merged(right)(mergef)` + * + * @param that node from the "right" HashMap. Must also be at the same "path" or "position" within the right tree, + * as `this` is, within the left tree + */ + def mergeInto[V1 >: V](that: MapNode[K, V1], builder: HashMapBuilder[K, V1], shift: Int)(mergef: ((K, V), (K, V1)) => (K, V1)): Unit + + /** Returns the exact (equal by reference) key, and value, associated to a given key. + * If the key is not bound to a value, then an exception is thrown + */ + def getTuple(key: K, originalHash: Int, hash: Int, shift: Int): (K, V) + + /** Adds all key-value pairs to a builder */ + def buildTo[V1 >: V](builder: HashMapBuilder[K, V1]): Unit +} + +private final class BitmapIndexedMapNode[K, +V]( + var dataMap: Int, + var nodeMap: Int, + var content: Array[Any], + var originalHashes: Array[Int], + var size: Int, + var cachedJavaKeySetHashCode: Int) extends MapNode[K, V] { + + releaseFence() + + import MapNode._ + import Node._ + + /* + assert(checkInvariantContentIsWellTyped()) + assert(checkInvariantSubNodesAreCompacted()) + + private final def checkInvariantSubNodesAreCompacted(): Boolean = + new MapKeyValueTupleIterator[K, V](this).size - payloadArity >= 2 * nodeArity + + private final def checkInvariantContentIsWellTyped(): Boolean = { + val predicate1 = TupleLength * payloadArity + nodeArity == content.length + + val predicate2 = Range(0, TupleLength * payloadArity) + .forall(i => content(i).isInstanceOf[MapNode[_, _]] == false) + + val predicate3 = Range(TupleLength * payloadArity, content.length) + .forall(i => content(i).isInstanceOf[MapNode[_, _]] == true) + + predicate1 && predicate2 && predicate3 + } + */ + + def getKey(index: Int): K = content(TupleLength * index).asInstanceOf[K] + def getValue(index: Int): V = content(TupleLength * index + 1).asInstanceOf[V] + + def getPayload(index: Int) = Tuple2( + content(TupleLength * index).asInstanceOf[K], + content(TupleLength * index + 1).asInstanceOf[V]) + + override def getHash(index: Int): Int = originalHashes(index) + + def getNode(index: Int): MapNode[K, V] = + content(content.length - 1 - index).asInstanceOf[MapNode[K, V]] + + def apply(key: K, originalHash: Int, keyHash: Int, shift: Int): V = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + if (key == getKey(index)) getValue(index) else throw new NoSuchElementException(s"key not found: $key") + } else if ((nodeMap & bitpos) != 0) { + getNode(indexFrom(nodeMap, mask, bitpos)).apply(key, originalHash, keyHash, shift + BitPartitionSize) + } else { + throw new NoSuchElementException(s"key not found: $key") + } + } + + def get(key: K, originalHash: Int, keyHash: Int, shift: Int): Option[V] = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val key0 = this.getKey(index) + if (key == key0) Some(this.getValue(index)) else None + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + this.getNode(index).get(key, originalHash, keyHash, shift + BitPartitionSize) + } else { + None + } + } + + override def getTuple(key: K, originalHash: Int, hash: Int, shift: Int): (K, V) = { + val mask = maskFrom(hash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val payload = getPayload(index) + if (key == payload._1) payload else throw new NoSuchElementException + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + getNode(index).getTuple(key, originalHash, hash, shift + BitPartitionSize) + } else { + throw new NoSuchElementException + } + } + + def getOrElse[V1 >: V](key: K, originalHash: Int, keyHash: Int, shift: Int, f: => V1): V1 = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val key0 = this.getKey(index) + if (key == key0) getValue(index) else f + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + this.getNode(index).getOrElse(key, originalHash, keyHash, shift + BitPartitionSize, f) + } else { + f + } + } + + override def containsKey(key: K, originalHash: Int, keyHash: Int, shift: Int): Boolean = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + // assert(hashes(index) == computeHash(this.getKey(index)), (hashes.toSeq, content.toSeq, index, key, keyHash, shift)) + (originalHashes(index) == originalHash) && key == getKey(index) + } else if ((nodeMap & bitpos) != 0) { + getNode(indexFrom(nodeMap, mask, bitpos)).containsKey(key, originalHash, keyHash, shift + BitPartitionSize) + } else { + false + } + } + + + def updated[V1 >: V](key: K, value: V1, originalHash: Int, keyHash: Int, shift: Int, replaceValue: Boolean): BitmapIndexedMapNode[K, V1] = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val key0 = getKey(index) + val key0UnimprovedHash = getHash(index) + if (key0UnimprovedHash == originalHash && key0 == key) { + if (replaceValue) { + val value0 = this.getValue(index) + if ((key0.asInstanceOf[AnyRef] eq key.asInstanceOf[AnyRef]) && (value0.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef])) + this + else copyAndSetValue(bitpos, key, value) + } else this + } else { + val value0 = this.getValue(index) + val key0Hash = improve(key0UnimprovedHash) + val subNodeNew = mergeTwoKeyValPairs(key0, value0, key0UnimprovedHash, key0Hash, key, value, originalHash, keyHash, shift + BitPartitionSize) + + copyAndMigrateFromInlineToNode(bitpos, key0Hash, subNodeNew) + } + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + val subNodeNew = subNode.updated(key, value, originalHash, keyHash, shift + BitPartitionSize, replaceValue) + + if (subNodeNew eq subNode) this else copyAndSetNode(bitpos, subNode, subNodeNew) + } else copyAndInsertValue(bitpos, key, originalHash, keyHash, value) + } + + /** A variant of `updated` which performs shallow mutations on the root (`this`), and if possible, on immediately + * descendant child nodes (only one level beneath `this`) + * + * The caller should pass a bitmap of child nodes of this node, which this method may mutate. + * If this method may mutate a child node, then if the updated key-value belongs in that child node, it will + * be shallowly mutated (its children will not be mutated). + * + * If instead this method may not mutate the child node in which the to-be-updated key-value pair belongs, then + * that child will be updated immutably, but the result will be mutably re-inserted as a child of this node. + * + * @param key the key to update + * @param value the value to set `key` to + * @param originalHash key.## + * @param keyHash the improved hash + * @param shallowlyMutableNodeMap bitmap of child nodes of this node, which can be shallowly mutated + * during the call to this method + * + * @return Int which is the bitwise OR of shallowlyMutableNodeMap and any freshly created nodes, which will be + * available for mutations in subsequent calls. + */ + def updateWithShallowMutations[V1 >: V](key: K, value: V1, originalHash: Int, keyHash: Int, shift: Int, shallowlyMutableNodeMap: Int): Int = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val key0 = getKey(index) + val key0UnimprovedHash = getHash(index) + if (key0UnimprovedHash == originalHash && key0 == key) { + val value0 = this.getValue(index) + if (!((key0.asInstanceOf[AnyRef] eq key.asInstanceOf[AnyRef]) && (value0.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef]))) { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + content(idx + 1) = value + } + shallowlyMutableNodeMap + } else { + val value0 = this.getValue(index) + val key0Hash = improve(key0UnimprovedHash) + + val subNodeNew = mergeTwoKeyValPairs(key0, value0, key0UnimprovedHash, key0Hash, key, value, originalHash, keyHash, shift + BitPartitionSize) + migrateFromInlineToNodeInPlace(bitpos, key0Hash, subNodeNew) + shallowlyMutableNodeMap | bitpos + } + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + val subNodeSize = subNode.size + val subNodeHashCode = subNode.cachedJavaKeySetHashCode + + var returnMutableNodeMap = shallowlyMutableNodeMap + + val subNodeNew: MapNode[K, V1] = subNode match { + case subNodeBm: BitmapIndexedMapNode[K, V] if (bitpos & shallowlyMutableNodeMap) != 0 => + subNodeBm.updateWithShallowMutations(key, value, originalHash, keyHash, shift + BitPartitionSize, 0) + subNodeBm + case _ => + val result = subNode.updated(key, value, originalHash, keyHash, shift + BitPartitionSize, replaceValue = true) + if (result ne subNode) { + returnMutableNodeMap |= bitpos + } + result + } + + this.content(this.content.length - 1 - this.nodeIndex(bitpos)) = subNodeNew + this.size = this.size - subNodeSize + subNodeNew.size + this.cachedJavaKeySetHashCode = this.cachedJavaKeySetHashCode - subNodeHashCode + subNodeNew.cachedJavaKeySetHashCode + returnMutableNodeMap + } else { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length + TupleLength) + + // copy 'src' and insert 2 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + dst(idx) = key + dst(idx + 1) = value + arraycopy(src, idx, dst, idx + TupleLength, src.length - idx) + + this.dataMap |= bitpos + this.content = dst + this.originalHashes = insertElement(originalHashes, dataIx, originalHash) + this.size += 1 + this.cachedJavaKeySetHashCode += keyHash + shallowlyMutableNodeMap + } + } + + def removed[V1 >: V](key: K, originalHash: Int, keyHash: Int, shift: Int): BitmapIndexedMapNode[K, V1] = { + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val key0 = this.getKey(index) + + if (key0 == key) { + if (this.payloadArity == 2 && this.nodeArity == 0) { + /* + * Create new node with remaining pair. The new node will a) either become the new root + * returned, or b) unwrapped and inlined during returning. + */ + val newDataMap = if (shift == 0) (dataMap ^ bitpos) else bitposFrom(maskFrom(keyHash, 0)) + if (index == 0) + new BitmapIndexedMapNode[K, V1](newDataMap, 0, Array(getKey(1), getValue(1)), Array(originalHashes(1)), 1, improve(getHash(1))) + else + new BitmapIndexedMapNode[K, V1](newDataMap, 0, Array(getKey(0), getValue(0)), Array(originalHashes(0)), 1, improve(getHash(0))) + } else copyAndRemoveValue(bitpos, keyHash) + } else this + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + + val subNodeNew = subNode.removed(key, originalHash, keyHash, shift + BitPartitionSize) + // assert(subNodeNew.size != 0, "Sub-node must have at least one element.") + + if (subNodeNew eq subNode) return this + + // cache just in case subNodeNew is a hashCollision node, in which in which case a little arithmetic is avoided + // in Vector#length + val subNodeNewSize = subNodeNew.size + + if (subNodeNewSize == 1) { + if (this.size == subNode.size) { + // subNode is the only child (no other data or node children of `this` exist) + // escalate (singleton or empty) result + subNodeNew.asInstanceOf[BitmapIndexedMapNode[K, V]] + } else { + // inline value (move to front) + copyAndMigrateFromNodeToInline(bitpos, subNode, subNodeNew) + } + } else if (subNodeNewSize > 1) { + // modify current node (set replacement node) + copyAndSetNode(bitpos, subNode, subNodeNew) + } else this + } else this + } + + def mergeTwoKeyValPairs[V1 >: V](key0: K, value0: V1, originalHash0: Int, keyHash0: Int, key1: K, value1: V1, originalHash1: Int, keyHash1: Int, shift: Int): MapNode[K, V1] = { + // assert(key0 != key1) + + if (shift >= HashCodeLength) { + new HashCollisionMapNode[K, V1](originalHash0, keyHash0, Vector((key0, value0), (key1, value1))) + } else { + val mask0 = maskFrom(keyHash0, shift) + val mask1 = maskFrom(keyHash1, shift) + val newCachedHash = keyHash0 + keyHash1 + + if (mask0 != mask1) { + // unique prefixes, payload fits on same level + val dataMap = bitposFrom(mask0) | bitposFrom(mask1) + + if (mask0 < mask1) { + new BitmapIndexedMapNode[K, V1](dataMap, 0, Array(key0, value0, key1, value1), Array(originalHash0, originalHash1), 2, newCachedHash) + } else { + new BitmapIndexedMapNode[K, V1](dataMap, 0, Array(key1, value1, key0, value0), Array(originalHash1, originalHash0), 2, newCachedHash) + } + } else { + // identical prefixes, payload must be disambiguated deeper in the trie + val nodeMap = bitposFrom(mask0) + val node = mergeTwoKeyValPairs(key0, value0, originalHash0, keyHash0, key1, value1, originalHash1, keyHash1, shift + BitPartitionSize) + new BitmapIndexedMapNode[K, V1](0, nodeMap, Array(node), Array.emptyIntArray, node.size, node.cachedJavaKeySetHashCode) + } + } + } + + def hasNodes: Boolean = nodeMap != 0 + + def nodeArity: Int = bitCount(nodeMap) + + def hasPayload: Boolean = dataMap != 0 + + def payloadArity: Int = bitCount(dataMap) + + def dataIndex(bitpos: Int) = bitCount(dataMap & (bitpos - 1)) + + def nodeIndex(bitpos: Int) = bitCount(nodeMap & (bitpos - 1)) + + def copyAndSetValue[V1 >: V](bitpos: Int, newKey: K, newValue: V1): BitmapIndexedMapNode[K, V1] = { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length) + + // copy 'src' and set 1 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, src.length) + //dst(idx) = newKey + dst(idx + 1) = newValue + new BitmapIndexedMapNode[K, V1](dataMap, nodeMap, dst, originalHashes, size, cachedJavaKeySetHashCode) + } + + def copyAndSetNode[V1 >: V](bitpos: Int, oldNode: MapNode[K, V1], newNode: MapNode[K, V1]): BitmapIndexedMapNode[K, V1] = { + val idx = this.content.length - 1 - this.nodeIndex(bitpos) + + val src = this.content + val dst = new Array[Any](src.length) + + // copy 'src' and set 1 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, src.length) + dst(idx) = newNode + new BitmapIndexedMapNode[K, V1]( + dataMap, + nodeMap, + dst, + originalHashes, + size - oldNode.size + newNode.size, + cachedJavaKeySetHashCode - oldNode.cachedJavaKeySetHashCode + newNode.cachedJavaKeySetHashCode + ) + } + + def copyAndInsertValue[V1 >: V](bitpos: Int, key: K, originalHash: Int, keyHash: Int, value: V1): BitmapIndexedMapNode[K, V1] = { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length + TupleLength) + + // copy 'src' and insert 2 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + dst(idx) = key + dst(idx + 1) = value + arraycopy(src, idx, dst, idx + TupleLength, src.length - idx) + + val dstHashes = insertElement(originalHashes, dataIx, originalHash) + + new BitmapIndexedMapNode[K, V1](dataMap | bitpos, nodeMap, dst, dstHashes, size + 1, cachedJavaKeySetHashCode + keyHash) + } + + def copyAndRemoveValue(bitpos: Int, keyHash: Int): BitmapIndexedMapNode[K, V] = { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length - TupleLength) + + // copy 'src' and remove 2 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + arraycopy(src, idx + TupleLength, dst, idx, src.length - idx - TupleLength) + + val dstHashes = removeElement(originalHashes, dataIx) + + new BitmapIndexedMapNode[K, V](dataMap ^ bitpos, nodeMap, dst, dstHashes, size - 1, cachedJavaKeySetHashCode - keyHash) + } + + /** Variant of `copyAndMigrateFromInlineToNode` which mutates `this` rather than returning a new node. + * + * @param bitpos the bit position of the data to migrate to node + * @param keyHash the improved hash of the key currently at `bitpos` + * @param node the node to place at `bitpos` beneath `this` + */ + def migrateFromInlineToNodeInPlace[V1 >: V](bitpos: Int, keyHash: Int, node: MapNode[K, V1]): this.type = { + val dataIx = dataIndex(bitpos) + val idxOld = TupleLength * dataIx + val idxNew = this.content.length - TupleLength - nodeIndex(bitpos) + + val src = this.content + val dst = new Array[Any](src.length - TupleLength + 1) + + // copy 'src' and remove 2 element(s) at position 'idxOld' and + // insert 1 element(s) at position 'idxNew' + // assert(idxOld <= idxNew) + arraycopy(src, 0, dst, 0, idxOld) + arraycopy(src, idxOld + TupleLength, dst, idxOld, idxNew - idxOld) + dst(idxNew) = node + arraycopy(src, idxNew + TupleLength, dst, idxNew + 1, src.length - idxNew - TupleLength) + + val dstHashes = removeElement(originalHashes, dataIx) + + this.dataMap = dataMap ^ bitpos + this.nodeMap = nodeMap | bitpos + this.content = dst + this.originalHashes = dstHashes + this.size = size - 1 + node.size + this.cachedJavaKeySetHashCode = cachedJavaKeySetHashCode - keyHash + node.cachedJavaKeySetHashCode + this + } + + def copyAndMigrateFromInlineToNode[V1 >: V](bitpos: Int, keyHash: Int, node: MapNode[K, V1]): BitmapIndexedMapNode[K, V1] = { + val dataIx = dataIndex(bitpos) + val idxOld = TupleLength * dataIx + val idxNew = this.content.length - TupleLength - nodeIndex(bitpos) + + val src = this.content + val dst = new Array[Any](src.length - TupleLength + 1) + + // copy 'src' and remove 2 element(s) at position 'idxOld' and + // insert 1 element(s) at position 'idxNew' + // assert(idxOld <= idxNew) + arraycopy(src, 0, dst, 0, idxOld) + arraycopy(src, idxOld + TupleLength, dst, idxOld, idxNew - idxOld) + dst(idxNew) = node + arraycopy(src, idxNew + TupleLength, dst, idxNew + 1, src.length - idxNew - TupleLength) + + val dstHashes = removeElement(originalHashes, dataIx) + + new BitmapIndexedMapNode[K, V1]( + dataMap = dataMap ^ bitpos, + nodeMap = nodeMap | bitpos, + content = dst, + originalHashes = dstHashes, + size = size - 1 + node.size, + cachedJavaKeySetHashCode = cachedJavaKeySetHashCode - keyHash + node.cachedJavaKeySetHashCode + ) + } + + def copyAndMigrateFromNodeToInline[V1 >: V](bitpos: Int, oldNode: MapNode[K, V1], node: MapNode[K, V1]): BitmapIndexedMapNode[K, V1] = { + val idxOld = this.content.length - 1 - nodeIndex(bitpos) + val dataIxNew = dataIndex(bitpos) + val idxNew = TupleLength * dataIxNew + + val key = node.getKey(0) + val value = node.getValue(0) + val src = this.content + val dst = new Array[Any](src.length - 1 + TupleLength) + + // copy 'src' and remove 1 element(s) at position 'idxOld' and + // insert 2 element(s) at position 'idxNew' + // assert(idxOld >= idxNew) + arraycopy(src, 0, dst, 0, idxNew) + dst(idxNew) = key + dst(idxNew + 1) = value + arraycopy(src, idxNew, dst, idxNew + TupleLength, idxOld - idxNew) + arraycopy(src, idxOld + 1, dst, idxOld + TupleLength, src.length - idxOld - 1) + val hash = node.getHash(0) + val dstHashes = insertElement(originalHashes, dataIxNew, hash) + new BitmapIndexedMapNode[K, V1]( + dataMap = dataMap | bitpos, + nodeMap = nodeMap ^ bitpos, + content = dst, + originalHashes = dstHashes, + size = size - oldNode.size + 1, + cachedJavaKeySetHashCode = cachedJavaKeySetHashCode - oldNode.cachedJavaKeySetHashCode + node.cachedJavaKeySetHashCode + ) + } + + override def foreach[U](f: ((K, V)) => U): Unit = { + val iN = payloadArity // arity doesn't change during this operation + var i = 0 + while (i < iN) { + f(getPayload(i)) + i += 1 + } + + val jN = nodeArity // arity doesn't change during this operation + var j = 0 + while (j < jN) { + getNode(j).foreach(f) + j += 1 + } + } + + override def foreachEntry[U](f: (K, V) => U): Unit = { + val iN = payloadArity // arity doesn't change during this operation + var i = 0 + while (i < iN) { + f(getKey(i), getValue(i)) + i += 1 + } + + val jN = nodeArity // arity doesn't change during this operation + var j = 0 + while (j < jN) { + getNode(j).foreachEntry(f) + j += 1 + } + } + + override def foreachWithHash(f: (K, V, Int) => Unit): Unit = { + var i = 0 + val iN = payloadArity // arity doesn't change during this operation + while (i < iN) { + f(getKey(i), getValue(i), getHash(i)) + i += 1 + } + + val jN = nodeArity // arity doesn't change during this operation + var j = 0 + while (j < jN) { + getNode(j).foreachWithHash(f) + j += 1 + } + } + override def buildTo[V1 >: V](builder: HashMapBuilder[K, V1]): Unit = { + var i = 0 + val iN = payloadArity + val jN = nodeArity + while (i < iN) { + builder.addOne(getKey(i), getValue(i), getHash(i)) + i += 1 + } + + var j = 0 + while (j < jN) { + getNode(j).buildTo(builder) + j += 1 + } + } + + override def transform[W](f: (K, V) => W): BitmapIndexedMapNode[K, W] = { + var newContent: Array[Any] = null + val iN = payloadArity // arity doesn't change during this operation + val jN = nodeArity // arity doesn't change during this operation + val newContentLength = content.length + var i = 0 + while (i < iN) { + val key = getKey(i) + val value = getValue(i) + val newValue = f(key, value) + if (newContent eq null) { + if (newValue.asInstanceOf[AnyRef] ne value.asInstanceOf[AnyRef]) { + newContent = content.clone() + newContent(TupleLength * i + 1) = newValue + } + } else { + newContent(TupleLength * i + 1) = newValue + } + i += 1 + } + + var j = 0 + while (j < jN) { + val node = getNode(j) + val newNode = node.transform(f) + if (newContent eq null) { + if (newNode ne node) { + newContent = content.clone() + newContent(newContentLength - j - 1) = newNode + } + } else + newContent(newContentLength - j - 1) = newNode + j += 1 + } + if (newContent eq null) this.asInstanceOf[BitmapIndexedMapNode[K, W]] + else new BitmapIndexedMapNode[K, W](dataMap, nodeMap, newContent, originalHashes, size, cachedJavaKeySetHashCode) + } + + override def mergeInto[V1 >: V](that: MapNode[K, V1], builder: HashMapBuilder[K, V1], shift: Int)(mergef: ((K, V), (K, V1)) => (K, V1)): Unit = that match { + case bm: BitmapIndexedMapNode[K, V] @unchecked => + if (size == 0) { + that.buildTo(builder) + return + } else if (bm.size == 0) { + buildTo(builder) + return + } + + val allMap = dataMap | bm.dataMap | nodeMap | bm.nodeMap + + val minIndex: Int = Integer.numberOfTrailingZeros(allMap) + val maxIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(allMap) + + { + var index = minIndex + var leftIdx = 0 + var rightIdx = 0 + + while (index < maxIndex) { + val bitpos = bitposFrom(index) + + if ((bitpos & dataMap) != 0) { + val leftKey = getKey(leftIdx) + val leftValue = getValue(leftIdx) + val leftOriginalHash = getHash(leftIdx) + if ((bitpos & bm.dataMap) != 0) { + // left data and right data + val rightKey = bm.getKey(rightIdx) + val rightValue = bm.getValue(rightIdx) + val rightOriginalHash = bm.getHash(rightIdx) + if (leftOriginalHash == rightOriginalHash && leftKey == rightKey) { + builder.addOne(mergef((leftKey, leftValue), (rightKey, rightValue))) + } else { + builder.addOne(leftKey, leftValue, leftOriginalHash) + builder.addOne(rightKey, rightValue, rightOriginalHash) + } + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + // left data and right node + val subNode = bm.getNode(bm.nodeIndex(bitpos)) + val leftImprovedHash = improve(leftOriginalHash) + val removed = subNode.removed(leftKey, leftOriginalHash, leftImprovedHash, shift + BitPartitionSize) + if (removed eq subNode) { + // no overlap in leftData and rightNode, just build both children to builder + subNode.buildTo(builder) + builder.addOne(leftKey, leftValue, leftOriginalHash, leftImprovedHash) + } else { + // there is collision, so special treatment for that key + removed.buildTo(builder) + builder.addOne(mergef((leftKey, leftValue), subNode.getTuple(leftKey, leftOriginalHash, leftImprovedHash, shift + BitPartitionSize))) + } + } else { + // left data and nothing on right + builder.addOne(leftKey, leftValue, leftOriginalHash) + } + leftIdx += 1 + } else if ((bitpos & nodeMap) != 0) { + if ((bitpos & bm.dataMap) != 0) { + // left node and right data + val rightKey = bm.getKey(rightIdx) + val rightValue = bm.getValue(rightIdx) + val rightOriginalHash = bm.getHash(rightIdx) + val rightImprovedHash = improve(rightOriginalHash) + + val subNode = getNode(nodeIndex(bitpos)) + val removed = subNode.removed(rightKey, rightOriginalHash, rightImprovedHash, shift + BitPartitionSize) + if (removed eq subNode) { + // no overlap in leftNode and rightData, just build both children to builder + subNode.buildTo(builder) + builder.addOne(rightKey, rightValue, rightOriginalHash, rightImprovedHash) + } else { + // there is collision, so special treatment for that key + removed.buildTo(builder) + builder.addOne(mergef(subNode.getTuple(rightKey, rightOriginalHash, rightImprovedHash, shift + BitPartitionSize), (rightKey, rightValue))) + } + rightIdx += 1 + + } else if ((bitpos & bm.nodeMap) != 0) { + // left node and right node + getNode(nodeIndex(bitpos)).mergeInto(bm.getNode(bm.nodeIndex(bitpos)), builder, shift + BitPartitionSize)(mergef) + } else { + // left node and nothing on right + getNode(nodeIndex(bitpos)).buildTo(builder) + } + } else if ((bitpos & bm.dataMap) != 0) { + // nothing on left, right data + val dataIndex = bm.dataIndex(bitpos) + builder.addOne(bm.getKey(dataIndex),bm.getValue(dataIndex), bm.getHash(dataIndex)) + rightIdx += 1 + + } else if ((bitpos & bm.nodeMap) != 0) { + // nothing on left, right node + bm.getNode(bm.nodeIndex(bitpos)).buildTo(builder) + } + + index += 1 + } + } + case _: HashCollisionMapNode[_, _] => + throw new Exception("Cannot merge BitmapIndexedMapNode with HashCollisionMapNode") + } + + override def equals(that: Any): Boolean = + that match { + case node: BitmapIndexedMapNode[_, _] => + (this eq node) || + (this.cachedJavaKeySetHashCode == node.cachedJavaKeySetHashCode) && + (this.nodeMap == node.nodeMap) && + (this.dataMap == node.dataMap) && + (this.size == node.size) && + java.util.Arrays.equals(this.originalHashes, node.originalHashes) && + deepContentEquality(this.content, node.content, content.length) + case _ => false + } + + @`inline` private def deepContentEquality(a1: Array[Any], a2: Array[Any], length: Int): Boolean = { + if (a1 eq a2) + true + else { + var isEqual = true + var i = 0 + + while (isEqual && i < length) { + isEqual = a1(i) == a2(i) + i += 1 + } + + isEqual + } + } + + override def hashCode(): Int = + throw new UnsupportedOperationException("Trie nodes do not support hashing.") + + override def concat[V1 >: V](that: MapNode[K, V1], shift: Int): BitmapIndexedMapNode[K, V1] = that match { + case bm: BitmapIndexedMapNode[K, V] @unchecked => + if (size == 0) return bm + else if (bm.size == 0 || (bm eq this)) return this + else if (bm.size == 1) { + val originalHash = bm.getHash(0) + return this.updated(bm.getKey(0), bm.getValue(0), originalHash, improve(originalHash), shift, replaceValue = true) + } + // if we go through the merge and the result does not differ from `bm`, we can just return `bm`, to improve sharing + // So, `anyChangesMadeSoFar` will be set to `true` as soon as we encounter a difference between the + // currently-being-computed result, and `bm` + var anyChangesMadeSoFar = false + + val allMap = dataMap | bm.dataMap | nodeMap | bm.nodeMap + + // minimumIndex is inclusive -- it is the first index for which there is data or nodes + val minimumBitPos: Int = Node.bitposFrom(Integer.numberOfTrailingZeros(allMap)) + // maximumIndex is inclusive -- it is the last index for which there is data or nodes + // it could not be exclusive, because then upper bound in worst case (Node.BranchingFactor) would be out-of-bound + // of int bitposition representation + val maximumBitPos: Int = Node.bitposFrom(Node.BranchingFactor - Integer.numberOfLeadingZeros(allMap) - 1) + + var leftNodeRightNode = 0 + var leftDataRightNode = 0 + var leftNodeRightData = 0 + var leftDataOnly = 0 + var rightDataOnly = 0 + var leftNodeOnly = 0 + var rightNodeOnly = 0 + var leftDataRightDataMigrateToNode = 0 + var leftDataRightDataRightOverwrites = 0 + + var dataToNodeMigrationTargets = 0 + + { + var bitpos = minimumBitPos + var leftIdx = 0 + var rightIdx = 0 + var finished = false + + while (!finished) { + + if ((bitpos & dataMap) != 0) { + if ((bitpos & bm.dataMap) != 0) { + val leftOriginalHash = getHash(leftIdx) + if (leftOriginalHash == bm.getHash(rightIdx) && getKey(leftIdx) == bm.getKey(rightIdx)) { + leftDataRightDataRightOverwrites |= bitpos + } else { + leftDataRightDataMigrateToNode |= bitpos + dataToNodeMigrationTargets |= Node.bitposFrom(Node.maskFrom(improve(leftOriginalHash), shift)) + } + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + leftDataRightNode |= bitpos + } else { + leftDataOnly |= bitpos + } + leftIdx += 1 + } else if ((bitpos & nodeMap) != 0) { + if ((bitpos & bm.dataMap) != 0) { + leftNodeRightData |= bitpos + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + leftNodeRightNode |= bitpos + } else { + leftNodeOnly |= bitpos + } + } else if ((bitpos & bm.dataMap) != 0) { + rightDataOnly |= bitpos + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + rightNodeOnly |= bitpos + } + + if (bitpos == maximumBitPos) { + finished = true + } else { + bitpos = bitpos << 1 + } + } + } + + + val newDataMap = leftDataOnly | rightDataOnly | leftDataRightDataRightOverwrites + + val newNodeMap = + leftNodeRightNode | + leftDataRightNode | + leftNodeRightData | + leftNodeOnly | + rightNodeOnly | + dataToNodeMigrationTargets + + + if ((newDataMap == (rightDataOnly | leftDataRightDataRightOverwrites)) && (newNodeMap == rightNodeOnly)) { + // nothing from `this` will make it into the result -- return early + return bm + } + + val newDataSize = bitCount(newDataMap) + val newContentSize = (MapNode.TupleLength * newDataSize) + bitCount(newNodeMap) + + val newContent = new Array[Any](newContentSize) + val newOriginalHashes = new Array[Int](newDataSize) + var newSize = 0 + var newCachedHashCode = 0 + + { + var leftDataIdx = 0 + var rightDataIdx = 0 + var leftNodeIdx = 0 + var rightNodeIdx = 0 + + val nextShift = shift + Node.BitPartitionSize + + var compressedDataIdx = 0 + var compressedNodeIdx = 0 + + var bitpos = minimumBitPos + var finished = false + + while (!finished) { + + if ((bitpos & leftNodeRightNode) != 0) { + val rightNode = bm.getNode(rightNodeIdx) + val newNode = getNode(leftNodeIdx).concat(rightNode, nextShift) + if (rightNode ne newNode) { + anyChangesMadeSoFar = true + } + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + rightNodeIdx += 1 + leftNodeIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + + } else if ((bitpos & leftDataRightNode) != 0) { + val newNode = { + val n = bm.getNode(rightNodeIdx) + val leftKey = getKey(leftDataIdx) + val leftValue = getValue(leftDataIdx) + val leftOriginalHash = getHash(leftDataIdx) + val leftImproved = improve(leftOriginalHash) + + val updated = n.updated(leftKey, leftValue, leftOriginalHash, leftImproved, nextShift, replaceValue = false) + + if (updated ne n) { + anyChangesMadeSoFar = true + } + + updated + } + + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + rightNodeIdx += 1 + leftDataIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } + else if ((bitpos & leftNodeRightData) != 0) { + anyChangesMadeSoFar = true + val newNode = { + val rightOriginalHash = bm.getHash(rightDataIdx) + getNode(leftNodeIdx).updated( + key = bm.getKey(rightDataIdx), + value = bm.getValue(rightDataIdx), + originalHash = bm.getHash(rightDataIdx), + hash = improve(rightOriginalHash), + shift = nextShift, + replaceValue = true + ) + } + + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + leftNodeIdx += 1 + rightDataIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + + } else if ((bitpos & leftDataOnly) != 0) { + anyChangesMadeSoFar = true + val originalHash = originalHashes(leftDataIdx) + newContent(MapNode.TupleLength * compressedDataIdx) = getKey(leftDataIdx).asInstanceOf[AnyRef] + newContent(MapNode.TupleLength * compressedDataIdx + 1) = getValue(leftDataIdx).asInstanceOf[AnyRef] + newOriginalHashes(compressedDataIdx) = originalHash + + compressedDataIdx += 1 + leftDataIdx += 1 + newSize += 1 + newCachedHashCode += improve(originalHash) + } else if ((bitpos & rightDataOnly) != 0) { + val originalHash = bm.originalHashes(rightDataIdx) + newContent(MapNode.TupleLength * compressedDataIdx) = bm.getKey(rightDataIdx).asInstanceOf[AnyRef] + newContent(MapNode.TupleLength * compressedDataIdx + 1) = bm.getValue(rightDataIdx).asInstanceOf[AnyRef] + newOriginalHashes(compressedDataIdx) = originalHash + + compressedDataIdx += 1 + rightDataIdx += 1 + newSize += 1 + newCachedHashCode += improve(originalHash) + } else if ((bitpos & leftNodeOnly) != 0) { + anyChangesMadeSoFar = true + val newNode = getNode(leftNodeIdx) + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + leftNodeIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } else if ((bitpos & rightNodeOnly) != 0) { + val newNode = bm.getNode(rightNodeIdx) + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + rightNodeIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } else if ((bitpos & leftDataRightDataMigrateToNode) != 0) { + anyChangesMadeSoFar = true + val newNode = { + val leftOriginalHash = getHash(leftDataIdx) + val rightOriginalHash = bm.getHash(rightDataIdx) + + bm.mergeTwoKeyValPairs( + getKey(leftDataIdx), getValue(leftDataIdx), leftOriginalHash, improve(leftOriginalHash), + bm.getKey(rightDataIdx), bm.getValue(rightDataIdx), rightOriginalHash, improve(rightOriginalHash), + nextShift + ) + } + + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + leftDataIdx += 1 + rightDataIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } else if ((bitpos & leftDataRightDataRightOverwrites) != 0) { + val originalHash = bm.originalHashes(rightDataIdx) + newContent(MapNode.TupleLength * compressedDataIdx) = bm.getKey(rightDataIdx).asInstanceOf[AnyRef] + newContent(MapNode.TupleLength * compressedDataIdx + 1) = bm.getValue(rightDataIdx).asInstanceOf[AnyRef] + newOriginalHashes(compressedDataIdx) = originalHash + + compressedDataIdx += 1 + rightDataIdx += 1 + newSize += 1 + newCachedHashCode += improve(originalHash) + leftDataIdx += 1 + } + + if (bitpos == maximumBitPos) { + finished = true + } else { + bitpos = bitpos << 1 + } + } + } + + if (anyChangesMadeSoFar) + new BitmapIndexedMapNode( + dataMap = newDataMap, + nodeMap = newNodeMap, + content = newContent, + originalHashes = newOriginalHashes, + size = newSize, + cachedJavaKeySetHashCode = newCachedHashCode + ) + else bm + + case _ => + // should never happen -- hash collisions are never at the same level as bitmapIndexedMapNodes + throw new UnsupportedOperationException("Cannot concatenate a HashCollisionMapNode with a BitmapIndexedMapNode") + } + + override def copy(): BitmapIndexedMapNode[K, V] = { + val contentClone = content.clone() + val contentLength = contentClone.length + var i = bitCount(dataMap) * TupleLength + while (i < contentLength) { + contentClone(i) = contentClone(i).asInstanceOf[MapNode[K, V]].copy() + i += 1 + } + new BitmapIndexedMapNode[K, V](dataMap, nodeMap, contentClone, originalHashes.clone(), size, cachedJavaKeySetHashCode) + } + + override def filterImpl(pred: ((K, V)) => Boolean, flipped: Boolean): BitmapIndexedMapNode[K, V] = { + if (size == 0) this + else if (size == 1) { + if (pred(getPayload(0)) != flipped) this else MapNode.empty + } else if (nodeMap == 0) { + // Performance optimization for nodes of depth 1: + // + // this node has no "node" children, all children are inlined data elems, therefor logic is significantly simpler + // approach: + // * traverse the content array, accumulating in `newDataMap: Int` any bit positions of keys which pass the filter + // * (bitCount(newDataMap) * TupleLength) tells us the new content array and originalHashes array size, so now perform allocations + // * traverse the content array once more, placing each passing element (according to `newDatamap`) in the new content and originalHashes arrays + // + // note: + // * this optimization significantly improves performance of not only small trees, but also larger trees, since + // even non-root nodes are affected by this improvement, and large trees will consist of many nodes as + // descendants + // + val minimumIndex: Int = Integer.numberOfTrailingZeros(dataMap) + val maximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(dataMap) + + var newDataMap = 0 + var newCachedHashCode = 0 + var dataIndex = 0 + + var i = minimumIndex + + while(i < maximumIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & dataMap) != 0) { + val payload = getPayload(dataIndex) + val passed = pred(payload) != flipped + + if (passed) { + newDataMap |= bitpos + newCachedHashCode += improve(getHash(dataIndex)) + } + + dataIndex += 1 + } + + i += 1 + } + + if (newDataMap == 0) { + MapNode.empty + } else if (newDataMap == dataMap) { + this + } else { + val newSize = Integer.bitCount(newDataMap) + val newContent = new Array[Any](newSize * TupleLength) + val newOriginalHashCodes = new Array[Int](newSize) + val newMaximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(newDataMap) + + var j = Integer.numberOfTrailingZeros(newDataMap) + + var newDataIndex = 0 + + + while (j < newMaximumIndex) { + val bitpos = bitposFrom(j) + if ((bitpos & newDataMap) != 0) { + val oldIndex = indexFrom(dataMap, bitpos) + newContent(newDataIndex * TupleLength) = content(oldIndex * TupleLength) + newContent(newDataIndex * TupleLength + 1) = content(oldIndex * TupleLength + 1) + newOriginalHashCodes(newDataIndex) = originalHashes(oldIndex) + newDataIndex += 1 + } + j += 1 + } + + new BitmapIndexedMapNode(newDataMap, 0, newContent, newOriginalHashCodes, newSize, newCachedHashCode) + } + + + } else { + val allMap = dataMap | nodeMap + val minimumIndex: Int = Integer.numberOfTrailingZeros(allMap) + val maximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(allMap) + + var oldDataPassThrough = 0 + + // bitmap of nodes which, when filtered, returned a single-element node. These must be migrated to data + var nodeMigrateToDataTargetMap = 0 + // the queue of single-element, post-filter nodes + var nodesToMigrateToData: mutable.Queue[MapNode[K, V]] = null + + // bitmap of all nodes which, when filtered, returned themselves. They are passed forward to the returned node + var nodesToPassThroughMap = 0 + + // bitmap of any nodes which, after being filtered, returned a node that is not empty, but also not `eq` itself + // These are stored for later inclusion into the final `content` array + // not named `newNodesMap` (plural) to avoid confusion with `newNodeMap` (singular) + var mapOfNewNodes = 0 + // each bit in `mapOfNewNodes` corresponds to one element in this queue + var newNodes: mutable.Queue[MapNode[K, V]] = null + + var newDataMap = 0 + var newNodeMap = 0 + var newSize = 0 + var newCachedHashCode = 0 + + var dataIndex = 0 + var nodeIndex = 0 + + var i = minimumIndex + while (i < maximumIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & dataMap) != 0) { + val payload = getPayload(dataIndex) + val passed = pred(payload) != flipped + + if (passed) { + newDataMap |= bitpos + oldDataPassThrough |= bitpos + newSize += 1 + newCachedHashCode += improve(getHash(dataIndex)) + } + + dataIndex += 1 + } else if ((bitpos & nodeMap) != 0) { + val oldSubNode = getNode(nodeIndex) + val newSubNode = oldSubNode.filterImpl(pred, flipped) + + newSize += newSubNode.size + newCachedHashCode += newSubNode.cachedJavaKeySetHashCode + + // if (newSubNode.size == 0) do nothing (drop it) + if (newSubNode.size > 1) { + newNodeMap |= bitpos + if (oldSubNode eq newSubNode) { + nodesToPassThroughMap |= bitpos + } else { + mapOfNewNodes |= bitpos + if (newNodes eq null) { + newNodes = mutable.Queue.empty[MapNode[K, V] @uncheckedCaptures] + } + newNodes += newSubNode + } + } else if (newSubNode.size == 1) { + newDataMap |= bitpos + nodeMigrateToDataTargetMap |= bitpos + if (nodesToMigrateToData eq null) { + nodesToMigrateToData = mutable.Queue() + } + nodesToMigrateToData += newSubNode + } + + nodeIndex += 1 + } + + i += 1 + } + + if (newSize == 0) { + MapNode.empty + } else if (newSize == size) { + this + } else { + val newDataSize = bitCount(newDataMap) + val newContentSize = (MapNode.TupleLength * newDataSize) + bitCount(newNodeMap) + val newContent = new Array[Any](newContentSize) + val newOriginalHashes = new Array[Int](newDataSize) + + val newAllMap = newDataMap | newNodeMap + val maxIndex = Node.BranchingFactor - Integer.numberOfLeadingZeros(newAllMap) + + // note: We MUST start from the minimum index in the old (`this`) node, otherwise `old{Node,Data}Index` will + // not be incremented properly. Otherwise we could have started at Integer.numberOfTrailingZeroes(newAllMap) + var i = minimumIndex + + var oldDataIndex = 0 + var oldNodeIndex = 0 + + var newDataIndex = 0 + var newNodeIndex = 0 + + while (i < maxIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & oldDataPassThrough) != 0) { + newContent(newDataIndex * TupleLength) = getKey(oldDataIndex) + newContent(newDataIndex * TupleLength + 1) = getValue(oldDataIndex) + newOriginalHashes(newDataIndex) = getHash(oldDataIndex) + newDataIndex += 1 + oldDataIndex += 1 + } else if ((bitpos & nodesToPassThroughMap) != 0) { + newContent(newContentSize - newNodeIndex - 1) = getNode(oldNodeIndex) + newNodeIndex += 1 + oldNodeIndex += 1 + } else if ((bitpos & nodeMigrateToDataTargetMap) != 0) { + // we need not check for null here. If nodeMigrateToDataTargetMap != 0, then nodesMigrateToData must not be null + val node = nodesToMigrateToData.dequeue() + newContent(TupleLength * newDataIndex) = node.getKey(0) + newContent(TupleLength * newDataIndex + 1) = node.getValue(0) + newOriginalHashes(newDataIndex) = node.getHash(0) + newDataIndex += 1 + oldNodeIndex += 1 + } else if ((bitpos & mapOfNewNodes) != 0) { + newContent(newContentSize - newNodeIndex - 1) = newNodes.dequeue() + newNodeIndex += 1 + oldNodeIndex += 1 + } else if ((bitpos & dataMap) != 0) { + oldDataIndex += 1 + } else if ((bitpos & nodeMap) != 0) { + oldNodeIndex += 1 + } + + i += 1 + } + + new BitmapIndexedMapNode[K, V](newDataMap, newNodeMap, newContent, newOriginalHashes, newSize, newCachedHashCode) + } + } + } +} + +private final class HashCollisionMapNode[K, +V ]( + val originalHash: Int, + val hash: Int, + var content: Vector[(K, V @uV) @uncheckedCaptures] + ) extends MapNode[K, V] { + + import Node._ + + require(content.length >= 2) + + releaseFence() + + private[immutable] def indexOf(key: Any): Int = { + val iter = content.iterator + var i = 0 + while (iter.hasNext) { + if (iter.next()._1 == key) return i + i += 1 + } + -1 + } + + def size: Int = content.length + + def apply(key: K, originalHash: Int, hash: Int, shift: Int): V = get(key, originalHash, hash, shift).getOrElse(throw new NoSuchElementException) + + def get(key: K, originalHash: Int, hash: Int, shift: Int): Option[V] = + if (this.hash == hash) { + val index = indexOf(key) + if (index >= 0) Some(content(index)._2) else None + } else None + + override def getTuple(key: K, originalHash: Int, hash: Int, shift: Int): (K, V) = { + val index = indexOf(key) + if (index >= 0) content(index) else throw new NoSuchElementException + } + + def getOrElse[V1 >: V](key: K, originalHash: Int, hash: Int, shift: Int, f: => V1): V1 = { + if (this.hash == hash) { + indexOf(key) match { + case -1 => f + case other => content(other)._2 + } + } else f + } + + override def containsKey(key: K, originalHash: Int, hash: Int, shift: Int): Boolean = + this.hash == hash && indexOf(key) >= 0 + + def contains[V1 >: V](key: K, value: V1, hash: Int, shift: Int): Boolean = + this.hash == hash && { + val index = indexOf(key) + index >= 0 && (content(index)._2.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef]) + } + + def updated[V1 >: V](key: K, value: V1, originalHash: Int, hash: Int, shift: Int, replaceValue: Boolean): MapNode[K, V1] = { + val index = indexOf(key) + if (index >= 0) { + if (replaceValue) { + if (content(index)._2.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef]) { + this + } else { + new HashCollisionMapNode[K, V1](originalHash, hash, content.updated[(K, V1)](index, (key, value))) + } + } else { + this + } + } else { + new HashCollisionMapNode[K, V1](originalHash, hash, content.appended[(K, V1)]((key, value))) + } + } + + def removed[V1 >: V](key: K, originalHash: Int, hash: Int, shift: Int): MapNode[K, V1] = { + if (!this.containsKey(key, originalHash, hash, shift)) { + this + } else { + val updatedContent = content.filterNot(keyValuePair => keyValuePair._1 == key) + // assert(updatedContent.size == content.size - 1) + + updatedContent.size match { + case 1 => + val (k, v) = updatedContent(0) + new BitmapIndexedMapNode[K, V1](bitposFrom(maskFrom(hash, 0)), 0, Array(k, v), Array(originalHash), 1, hash) + case _ => new HashCollisionMapNode[K, V1](originalHash, hash, updatedContent) + } + } + } + + def hasNodes: Boolean = false + + def nodeArity: Int = 0 + + def getNode(index: Int): MapNode[K, V] = + throw new IndexOutOfBoundsException("No sub-nodes present in hash-collision leaf node.") + + def hasPayload: Boolean = true + + def payloadArity: Int = content.length + + def getKey(index: Int): K = getPayload(index)._1 + def getValue(index: Int): V = getPayload(index)._2 + + def getPayload(index: Int): (K, V) = content(index) + + override def getHash(index: Int): Int = originalHash + + def foreach[U](f: ((K, V)) => U): Unit = content.foreach(f) + + def foreachEntry[U](f: (K, V) => U): Unit = content.foreach { case (k, v) => f(k, v)} + + override def foreachWithHash(f: (K, V, Int) => Unit): Unit = { + val iter = content.iterator + while (iter.hasNext) { + val next = iter.next() + f(next._1, next._2, originalHash) + } + } + + override def transform[W](f: (K, V) => W): HashCollisionMapNode[K, W] = { + val newContent = Vector.newBuilder[(K, W)] + val contentIter = content.iterator + // true if any values have been transformed to a different value via `f` + var anyChanges = false + while(contentIter.hasNext) { + val (k, v) = contentIter.next() + val newValue = f(k, v) + newContent.addOne((k, newValue)) + anyChanges ||= (v.asInstanceOf[AnyRef] ne newValue.asInstanceOf[AnyRef]) + } + if (anyChanges) new HashCollisionMapNode(originalHash, hash, newContent.result()) + else this.asInstanceOf[HashCollisionMapNode[K, W]] + } + + override def equals(that: Any): Boolean = + that match { + case node: HashCollisionMapNode[_, _] => + (this eq node) || + (this.hash == node.hash) && + (this.content.length == node.content.length) && { + val iter = content.iterator + while (iter.hasNext) { + val (key, value) = iter.next() + val index = node.indexOf(key) + if (index < 0 || value != node.content(index)._2) { + return false + } + } + true + } + case _ => false + } + + override def concat[V1 >: V](that: MapNode[K, V1], shift: Int): HashCollisionMapNode[K, V1] = that match { + case hc: HashCollisionMapNode[K, V1] => + if (hc eq this) { + this + } else { + var newContent: VectorBuilder[(K, V1)] = null + val iter = content.iterator + while (iter.hasNext) { + val nextPayload = iter.next() + if (hc.indexOf(nextPayload._1) < 0) { + if (newContent eq null) { + newContent = new VectorBuilder[(K, V1)]() + newContent.addAll(hc.content) + } + newContent.addOne(nextPayload) + } + } + if (newContent eq null) hc else new HashCollisionMapNode(originalHash, hash, newContent.result()) + } + case _: BitmapIndexedMapNode[K, V1] => + // should never happen -- hash collisions are never at the same level as bitmapIndexedMapNodes + throw new UnsupportedOperationException("Cannot concatenate a HashCollisionMapNode with a BitmapIndexedMapNode") + } + + + override def mergeInto[V1 >: V](that: MapNode[K, V1], builder: HashMapBuilder[K, V1], shift: Int)(mergef: ((K, V), (K, V1)) => (K, V1)): Unit = that match { + case hc: HashCollisionMapNode[K, V1] => + val iter = content.iterator + val rightArray = hc.content.toArray[AnyRef] // really Array[(K, V1)] + + def rightIndexOf(key: K): Int = { + var i = 0 + while (i < rightArray.length) { + val elem = rightArray(i) + if ((elem ne null) && (elem.asInstanceOf[(K, V1)])._1 == key) return i + i += 1 + } + -1 + } + + while (iter.hasNext) { + val nextPayload = iter.next() + val index = rightIndexOf(nextPayload._1) + + if (index == -1) { + builder.addOne(nextPayload) + } else { + val rightPayload = rightArray(index).asInstanceOf[(K, V1)] + rightArray(index) = null + + builder.addOne(mergef(nextPayload, rightPayload)) + } + } + + var i = 0 + while (i < rightArray.length) { + val elem = rightArray(i) + if (elem ne null) builder.addOne(elem.asInstanceOf[(K, V1)]) + i += 1 + } + case _: BitmapIndexedMapNode[K, V1] => + throw new Exception("Cannot merge HashCollisionMapNode with BitmapIndexedMapNode") + + } + + override def buildTo[V1 >: V](builder: HashMapBuilder[K, V1]): Unit = { + val iter = content.iterator + while (iter.hasNext) { + val (k, v) = iter.next() + builder.addOne(k, v, originalHash, hash) + } + } + + override def filterImpl(pred: ((K, V)) => Boolean, flipped: Boolean): MapNode[K, V] = { + val newContent = content.filterImpl(pred, flipped) + val newContentLength = newContent.length + if (newContentLength == 0) { + MapNode.empty + } else if (newContentLength == 1) { + val (k, v) = newContent.head + new BitmapIndexedMapNode[K, V](bitposFrom(maskFrom(hash, 0)), 0, Array(k, v), Array(originalHash), 1, hash) + } else if (newContentLength == content.length) this + else new HashCollisionMapNode(originalHash, hash, newContent) + } + + override def copy(): HashCollisionMapNode[K, V] = new HashCollisionMapNode[K, V](originalHash, hash, content) + + override def hashCode(): Int = + throw new UnsupportedOperationException("Trie nodes do not support hashing.") + + override def cachedJavaKeySetHashCode: Int = size * hash + +} + +private final class MapKeyIterator[K, V](rootNode: MapNode[K, V]) + extends ChampBaseIterator[MapNode[K, V]](rootNode) with Iterator[K] { + + def next() = { + if (!hasNext) + throw new NoSuchElementException + + val key = currentValueNode.getKey(currentValueCursor) + currentValueCursor += 1 + + key + } + +} + +private final class MapValueIterator[K, V](rootNode: MapNode[K, V]) + extends ChampBaseIterator[MapNode[K, V]](rootNode) with Iterator[V] { + + def next() = { + if (!hasNext) + throw new NoSuchElementException + + val value = currentValueNode.getValue(currentValueCursor) + currentValueCursor += 1 + + value + } +} + +private final class MapKeyValueTupleIterator[K, V](rootNode: MapNode[K, V]) + extends ChampBaseIterator[MapNode[K, V]](rootNode) with Iterator[(K, V)] { + + def next() = { + if (!hasNext) + throw new NoSuchElementException + + val payload = currentValueNode.getPayload(currentValueCursor) + currentValueCursor += 1 + + payload + } + +} + +private final class MapKeyValueTupleReverseIterator[K, V](rootNode: MapNode[K, V]) + extends ChampBaseReverseIterator[MapNode[K, V]](rootNode) with Iterator[(K, V)] { + + def next() = { + if (!hasNext) + throw new NoSuchElementException + + val payload = currentValueNode.getPayload(currentValueCursor) + currentValueCursor -= 1 + + payload + } +} + +private final class MapKeyValueTupleHashIterator[K, V](rootNode: MapNode[K, V]) + extends ChampBaseReverseIterator[MapNode[K, V]](rootNode) with Iterator[Any] { + private[this] var hash = 0 + private[this] var value: V @uncheckedCaptures = _ + override def hashCode(): Int = MurmurHash3.tuple2Hash(hash, value.##, MurmurHash3.productSeed) + def next() = { + if (!hasNext) + throw new NoSuchElementException + + hash = currentValueNode.getHash(currentValueCursor) + value = currentValueNode.getValue(currentValueCursor) + currentValueCursor -= 1 + this + } +} + +/** Used in HashMap[K, V]#removeAll(HashSet[K]) */ +private final class MapNodeRemoveAllSetNodeIterator[K](rootSetNode: SetNode[K]) extends ChampBaseIterator(rootSetNode) { + /** Returns the result of immutably removing all keys in `rootSetNode` from `rootMapNode` */ + def removeAll[V](rootMapNode: BitmapIndexedMapNode[K, V]): BitmapIndexedMapNode[K, V] = { + var curr = rootMapNode + while (curr.size > 0 && hasNext) { + val originalHash = currentValueNode.getHash(currentValueCursor) + curr = curr.removed( + key = currentValueNode.getPayload(currentValueCursor), + keyHash = improve(originalHash), + originalHash = originalHash, + shift = 0 + ) + currentValueCursor += 1 + } + curr + } +} + +/** + * $factoryInfo + * + * @define Coll `immutable.HashMap` + * @define coll immutable champ hash map + */ +@SerialVersionUID(3L) +object HashMap extends MapFactory[HashMap] { + + @transient + private final val EmptyMap = new HashMap(MapNode.empty) + + def empty[K, V]: HashMap[K, V] = + EmptyMap.asInstanceOf[HashMap[K, V]] + + def from[K, V](source: collection.IterableOnce[(K, V)]^): HashMap[K, V] = + source match { + case hs: HashMap[K, V] => hs + case _ => (newBuilder[K, V] ++= source).result() + } + + /** Create a new Builder which can be reused after calling `result()` without an + * intermediate call to `clear()` in order to build multiple related results. + */ + def newBuilder[K, V]: ReusableBuilder[(K, V), HashMap[K, V]] = new HashMapBuilder[K, V] +} + + +/** A Builder for a HashMap. + * $multipleResults + */ +private[immutable] final class HashMapBuilder[K, V] extends ReusableBuilder[(K, V), HashMap[K, V]] { + import MapNode._ + import Node._ + + private def newEmptyRootNode = new BitmapIndexedMapNode[K, V](0, 0, Array.emptyObjectArray.asInstanceOf[Array[Any]], Array.emptyIntArray, 0, 0) + + /** The last given out HashMap as a return value of `result()`, if any, otherwise null. + * Indicates that on next add, the elements should be copied to an identical structure, before continuing + * mutations. */ + private var aliased: HashMap[K, V] @uncheckedCaptures = _ + + private def isAliased: Boolean = aliased != null + + /** The root node of the partially build hashmap */ + private var rootNode: BitmapIndexedMapNode[K, V] @uncheckedCaptures = newEmptyRootNode + + private[immutable] def getOrElse[V0 >: V](key: K, value: V0): V0 = + if (rootNode.size == 0) value + else { + val originalHash = key.## + rootNode.getOrElse(key, originalHash, improve(originalHash), 0, value) + } + + /** Inserts element `elem` into array `as` at index `ix`, shifting right the trailing elems */ + private[this] def insertElement(as: Array[Int], ix: Int, elem: Int): Array[Int] = { + if (ix < 0) throw new ArrayIndexOutOfBoundsException + if (ix > as.length) throw new ArrayIndexOutOfBoundsException + val result = new Array[Int](as.length + 1) + arraycopy(as, 0, result, 0, ix) + result(ix) = elem + arraycopy(as, ix, result, ix + 1, as.length - ix) + result + } + + /** Inserts key-value into the bitmapIndexMapNode. Requires that this is a new key-value pair */ + private[this] def insertValue[V1 >: V](bm: BitmapIndexedMapNode[K, V],bitpos: Int, key: K, originalHash: Int, keyHash: Int, value: V1): Unit = { + val dataIx = bm.dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = bm.content + val dst = new Array[Any](src.length + TupleLength) + + // copy 'src' and insert 2 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + dst(idx) = key + dst(idx + 1) = value + arraycopy(src, idx, dst, idx + TupleLength, src.length - idx) + + val dstHashes = insertElement(bm.originalHashes, dataIx, originalHash) + + bm.dataMap |= bitpos + bm.content = dst + bm.originalHashes = dstHashes + bm.size += 1 + bm.cachedJavaKeySetHashCode += keyHash + } + + /** Upserts a key/value pair into mapNode, mutably */ + private[immutable] def update(mapNode: MapNode[K, V], key: K, value: V, originalHash: Int, keyHash: Int, shift: Int): Unit = { + mapNode match { + case bm: BitmapIndexedMapNode[K, V] => + val mask = maskFrom(keyHash, shift) + val bitpos = bitposFrom(mask) + if ((bm.dataMap & bitpos) != 0) { + val index = indexFrom(bm.dataMap, mask, bitpos) + val key0 = bm.getKey(index) + val key0UnimprovedHash = bm.getHash(index) + + if (key0UnimprovedHash == originalHash && key0 == key) { + bm.content(TupleLength * index + 1) = value + } else { + val value0 = bm.getValue(index) + val key0Hash = improve(key0UnimprovedHash) + + val subNodeNew: MapNode[K, V] = + bm.mergeTwoKeyValPairs(key0, value0, key0UnimprovedHash, key0Hash, key, value, originalHash, keyHash, shift + BitPartitionSize) + + bm.migrateFromInlineToNodeInPlace(bitpos, key0Hash, subNodeNew) + } + + } else if ((bm.nodeMap & bitpos) != 0) { + val index = indexFrom(bm.nodeMap, mask, bitpos) + val subNode = bm.getNode(index) + val beforeSize = subNode.size + val beforeHash = subNode.cachedJavaKeySetHashCode + update(subNode, key, value, originalHash, keyHash, shift + BitPartitionSize) + bm.size += subNode.size - beforeSize + bm.cachedJavaKeySetHashCode += subNode.cachedJavaKeySetHashCode - beforeHash + } else { + insertValue(bm, bitpos, key, originalHash, keyHash, value) + } + case hc: HashCollisionMapNode[K, V] => + val index = hc.indexOf(key) + if (index < 0) { + hc.content = hc.content.appended((key, value)) + } else { + hc.content = hc.content.updated(index, (key, value)) + } + } + } + + /** If currently referencing aliased structure, copy elements to new mutable structure */ + private[this] def ensureUnaliased() = { + if (isAliased) copyElems() + aliased = null + } + + /** Copy elements to new mutable structure */ + private[this] def copyElems(): Unit = { + rootNode = rootNode.copy() + } + + override def result(): HashMap[K, V] = + if (rootNode.size == 0) { + HashMap.empty + } else if (aliased != null) { + aliased + } else { + aliased = new HashMap(rootNode) + releaseFence() + aliased + } + + override def addOne(elem: (K, V)): this.type = { + ensureUnaliased() + val h = elem._1.## + val im = improve(h) + update(rootNode, elem._1, elem._2, h, im, 0) + this + } + + def addOne(key: K, value: V): this.type = { + ensureUnaliased() + val originalHash = key.## + update(rootNode, key, value, originalHash, improve(originalHash), 0) + this + } + def addOne(key: K, value: V, originalHash: Int): this.type = { + ensureUnaliased() + update(rootNode, key, value, originalHash, improve(originalHash), 0) + this + } + def addOne(key: K, value: V, originalHash: Int, hash: Int): this.type = { + ensureUnaliased() + update(rootNode, key, value, originalHash, hash, 0) + this + } + + override def addAll(xs: IterableOnce[(K, V)]^): this.type = { + ensureUnaliased() + xs match { + case hm: HashMap[K, V] => + new ChampBaseIterator[MapNode[K, V]](hm.rootNode) { + while(hasNext) { + val originalHash = currentValueNode.getHash(currentValueCursor) + update( + mapNode = rootNode, + key = currentValueNode.getKey(currentValueCursor), + value = currentValueNode.getValue(currentValueCursor), + originalHash = originalHash, + keyHash = improve(originalHash), + shift = 0 + ) + currentValueCursor += 1 + } + }.asInstanceOf // !!! cc gets confused with representation of capture sets in invariant position + case hm: collection.mutable.HashMap[K, V] => + val iter = hm.nodeIterator + while (iter.hasNext) { + val next = iter.next() + val originalHash = hm.unimproveHash(next.hash) + val hash = improve(originalHash) + update(rootNode, next.key, next.value, originalHash, hash, 0) + } + case lhm: collection.mutable.LinkedHashMap[K, V] => + val iter = lhm.entryIterator + while (iter.hasNext) { + val next = iter.next() + val originalHash = lhm.unimproveHash(next.hash) + val hash = improve(originalHash) + update(rootNode, next.key, next.value, originalHash, hash, 0) + } + case thatMap: Map[K, V] => + thatMap.foreachEntry((key, value) => addOne(key, value)) + case other => + val it = other.iterator + while(it.hasNext) addOne(it.next()) + } + + this + } + + override def clear(): Unit = { + aliased = null + if (rootNode.size > 0) { + rootNode = newEmptyRootNode + } + } + + private[collection] def size: Int = rootNode.size + + override def knownSize: Int = rootNode.size +} diff --git a/tests/pos-special/stdlib/collection/immutable/HashSet.scala b/tests/pos-special/stdlib/collection/immutable/HashSet.scala new file mode 100644 index 000000000000..38f394a7005f --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/HashSet.scala @@ -0,0 +1,2125 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import java.lang.Integer.{bitCount, numberOfTrailingZeros} +import java.lang.System.arraycopy + +import scala.collection.Hashing.improve +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.mutable.ReusableBuilder +import scala.runtime.Statics.releaseFence +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** This class implements immutable sets using a Compressed Hash-Array Mapped Prefix-tree. + * See paper https://michael.steindorfer.name/publications/oopsla15.pdf for more details. + * + * @tparam A the type of the elements contained in this hash set. + * @define Coll `immutable.HashSet` + * @define coll immutable champ hash set + */ +final class HashSet[A] private[immutable](private[immutable] val rootNode: BitmapIndexedSetNode[A]) + extends AbstractSet[A] + with StrictOptimizedSetOps[A, HashSet, HashSet[A]] + with IterableFactoryDefaults[A, HashSet] + with DefaultSerializable { + + def this() = this(SetNode.empty) + + // This release fence is present because rootNode may have previously been mutated during construction. + releaseFence() + + private[this] def newHashSetOrThis(newRootNode: BitmapIndexedSetNode[A]): HashSet[A] = + if (rootNode eq newRootNode) this else new HashSet(newRootNode) + + override def iterableFactory: IterableFactory[HashSet] = HashSet + + override def knownSize: Int = rootNode.size + + override def size: Int = rootNode.size + + override def isEmpty: Boolean = rootNode.size == 0 + + def iterator: Iterator[A] = { + if (isEmpty) Iterator.empty + else new SetIterator[A](rootNode) + } + + protected[immutable] def reverseIterator: Iterator[A] = new SetReverseIterator[A](rootNode) + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + import convert.impl._ + val s = shape.shape match { + case StepperShape.IntShape => IntChampStepper.from[ SetNode[A]](size, rootNode, (node, i) => node.getPayload(i).asInstanceOf[Int]) + case StepperShape.LongShape => LongChampStepper.from[ SetNode[A]](size, rootNode, (node, i) => node.getPayload(i).asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleChampStepper.from[SetNode[A]](size, rootNode, (node, i) => node.getPayload(i).asInstanceOf[Double]) + case _ => shape.parUnbox(AnyChampStepper.from[A, SetNode[A]](size, rootNode, (node, i) => node.getPayload(i))) + } + s.asInstanceOf[S with EfficientSplit] + } + + def contains(element: A): Boolean = { + val elementUnimprovedHash = element.## + val elementHash = improve(elementUnimprovedHash) + rootNode.contains(element, elementUnimprovedHash, elementHash, 0) + } + + def incl(element: A): HashSet[A] = { + val elementUnimprovedHash = element.## + val elementHash = improve(elementUnimprovedHash) + val newRootNode = rootNode.updated(element, elementUnimprovedHash, elementHash, 0) + newHashSetOrThis(newRootNode) + } + + def excl(element: A): HashSet[A] = { + val elementUnimprovedHash = element.## + val elementHash = improve(elementUnimprovedHash) + val newRootNode = rootNode.removed(element, elementUnimprovedHash, elementHash, 0) + newHashSetOrThis(newRootNode) + } + + override def concat(that: IterableOnce[A]): HashSet[A] = + that match { + case hs: HashSet[A] => + if (isEmpty) hs + else { + val newNode = rootNode.concat(hs.rootNode, 0) + if (newNode eq hs.rootNode) hs + else newHashSetOrThis(newNode) + } + case hs: collection.mutable.HashSet[A] => + val iter = hs.nodeIterator + var current = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = hs.unimproveHash(next.hash) + val improved = improve(originalHash) + current = current.updated(next.key, originalHash, improved, 0) + + if (current ne rootNode) { + var shallowlyMutableNodeMap = Node.bitposFrom(Node.maskFrom(improved, 0)) + while (iter.hasNext) { + val next = iter.next() + val originalHash = hs.unimproveHash(next.hash) + val improved = improve(originalHash) + shallowlyMutableNodeMap = current.updateWithShallowMutations(next.key, originalHash, improved, 0, shallowlyMutableNodeMap) + } + return new HashSet(current) + } + } + this + case lhs: collection.mutable.LinkedHashSet[A] => + val iter = lhs.entryIterator + var current = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = lhs.unimproveHash(next.hash) + val improved = improve(originalHash) + current = current.updated(next.key, originalHash, improved, 0) + + if (current ne rootNode) { + var shallowlyMutableNodeMap = Node.bitposFrom(Node.maskFrom(improved, 0)) + while (iter.hasNext) { + val next = iter.next() + val originalHash = lhs.unimproveHash(next.hash) + val improved = improve(originalHash) + shallowlyMutableNodeMap = current.updateWithShallowMutations(next.key, originalHash, improved, 0, shallowlyMutableNodeMap) + } + return new HashSet(current) + } + } + this + case _ => + val iter = that.iterator + var current = rootNode + while (iter.hasNext) { + val element = iter.next() + val originalHash = element.## + val improved = improve(originalHash) + current = current.updated(element, originalHash, improved, 0) + + if (current ne rootNode) { + // Note: We could have started with shallowlyMutableNodeMap = 0, however this way, in the case that + // the first changed key ended up in a subnode beneath root, we mark that root right away as being + // shallowly mutable. + // + // since `element` has just been inserted, and certainly caused a new root node to be created, we can say with + // certainty that it either caused a new subnode to be created underneath `current`, in which case we should + // carry on mutating that subnode, or it ended up as a child data pair of the root, in which case, no harm is + // done by including its bit position in the shallowlyMutableNodeMap anyways. + var shallowlyMutableNodeMap = Node.bitposFrom(Node.maskFrom(improved, 0)) + while (iter.hasNext) { + val element = iter.next() + val originalHash = element.## + val improved = improve(originalHash) + shallowlyMutableNodeMap = current.updateWithShallowMutations(element, originalHash, improved, 0, shallowlyMutableNodeMap) + } + return new HashSet(current) + } + } + this + } + + override def tail: HashSet[A] = this - head + + override def init: HashSet[A] = this - last + + override def head: A = iterator.next() + + override def last: A = reverseIterator.next() + + override def foreach[U](f: A => U): Unit = rootNode.foreach(f) + + /** Applies a function f to each element, and its corresponding **original** hash, in this Set */ + @`inline` private[collection] def foreachWithHash(f: (A, Int) => Unit): Unit = rootNode.foreachWithHash(f) + + /** Applies a function f to each element, and its corresponding **original** hash, in this Set + * Stops iterating the first time that f returns `false`.*/ + @`inline` private[collection] def foreachWithHashWhile(f: (A, Int) => Boolean): Unit = rootNode.foreachWithHashWhile(f) + + def subsetOf(that: Set[A]): Boolean = if (that.isEmpty) true else that match { + case set: HashSet[A] => rootNode.subsetOf(set.rootNode, 0) + case _ => super.subsetOf(that) + } + + override def equals(that: Any): Boolean = + that match { + case set: HashSet[_] => (this eq set) || (this.rootNode == set.rootNode) + case _ => super.equals(that) + } + + override protected[this] def className = "HashSet" + + override def hashCode(): Int = { + val it = new SetHashIterator(rootNode) + val hash = MurmurHash3.unorderedHash(it, MurmurHash3.setSeed) + //assert(hash == super.hashCode()) + hash + } + + override def diff(that: collection.Set[A]): HashSet[A] = { + if (isEmpty) { + this + } else { + that match { + case hashSet: HashSet[A] => + if (hashSet.isEmpty) this else { + val newRootNode = rootNode.diff(hashSet.rootNode, 0) + if (newRootNode.size == 0) HashSet.empty else newHashSetOrThis(rootNode.diff(hashSet.rootNode, 0)) + } + case hashSet: collection.mutable.HashSet[A] => + val iter = hashSet.nodeIterator + var curr = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = hashSet.unimproveHash(next.hash) + val improved = improve(originalHash) + curr = curr.removed(next.key, originalHash, improved, 0) + if (curr ne rootNode) { + if (curr.size == 0) { + return HashSet.empty + } + while (iter.hasNext) { + val next = iter.next() + val originalHash = hashSet.unimproveHash(next.hash) + val improved = improve(originalHash) + + curr.removeWithShallowMutations(next.key, originalHash, improved) + + if (curr.size == 0) { + return HashSet.empty + } + } + return new HashSet(curr) + } + } + this + + case other => + val thatKnownSize = other.knownSize + + if (thatKnownSize == 0) { + this + } else if (thatKnownSize <= size) { + /* this branch intentionally includes the case of thatKnownSize == -1. We know that HashSets are quite fast at look-up, so + we're likely to be the faster of the two at that. */ + removedAllWithShallowMutations(other) + } else { + // TODO: Develop more sophisticated heuristic for which branch to take + filterNot(other.contains) + } + } + + } + } + + /** Immutably removes all elements of `that` from this HashSet + * + * Mutation is used internally, but only on root SetNodes which this method itself creates. + * + * That is, this method is safe to call on published sets because it does not mutate `this` + */ + private[this] def removedAllWithShallowMutations(that: IterableOnce[A]): HashSet[A] = { + val iter = that.iterator + var curr = rootNode + while (iter.hasNext) { + val next = iter.next() + val originalHash = next.## + val improved = improve(originalHash) + curr = curr.removed(next, originalHash, improved, 0) + if (curr ne rootNode) { + if (curr.size == 0) { + return HashSet.empty + } + while (iter.hasNext) { + val next = iter.next() + val originalHash = next.## + val improved = improve(originalHash) + + curr.removeWithShallowMutations(next, originalHash, improved) + + if (curr.size == 0) { + return HashSet.empty + } + } + return new HashSet(curr) + } + } + this + } + + override def removedAll(that: IterableOnce[A]): HashSet[A] = that match { + case set: scala.collection.Set[A] => diff(set) + case range: Range if range.length > size => + filter { + case i: Int => !range.contains(i) + case _ => true + } + + case _ => + removedAllWithShallowMutations(that) + } + + override def partition(p: A => Boolean): (HashSet[A], HashSet[A]) = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.partition(p) + } + + override def span(p: A => Boolean): (HashSet[A], HashSet[A]) = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.span(p) + } + + override protected[collection] def filterImpl(pred: A => Boolean, isFlipped: Boolean): HashSet[A] = { + val newRootNode = rootNode.filterImpl(pred, isFlipped) + if (newRootNode eq rootNode) this + else if (newRootNode.size == 0) HashSet.empty + else new HashSet(newRootNode) + } + + override def intersect(that: collection.Set[A]): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.intersect(that) + } + + override def take(n: Int): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.take(n) + } + + override def takeRight(n: Int): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.takeRight(n) + } + + override def takeWhile(p: A => Boolean): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.takeWhile(p) + } + + override def drop(n: Int): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.drop(n) + } + + override def dropRight(n: Int): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.dropRight(n) + } + + override def dropWhile(p: A => Boolean): HashSet[A] = { + // This method has been preemptively overridden in order to ensure that an optimizing implementation may be included + // in a minor release without breaking binary compatibility. + super.dropWhile(p) + } +} + +private[immutable] object SetNode { + + private final val EmptySetNode = new BitmapIndexedSetNode(0, 0, Array.empty, Array.empty, 0, 0) + + def empty[A]: BitmapIndexedSetNode[A] = EmptySetNode.asInstanceOf[BitmapIndexedSetNode[A]] + + final val TupleLength = 1 + +} + +private[immutable] sealed abstract class SetNode[A] extends Node[SetNode[A]] { + + def contains(element: A, originalHash: Int, hash: Int, shift: Int): Boolean + + def updated(element: A, originalHash: Int, hash: Int, shift: Int): SetNode[A] + + def removed(element: A, originalHash: Int, hash: Int, shift: Int): SetNode[A] + + def hasNodes: Boolean + + def nodeArity: Int + + def getNode(index: Int): SetNode[A] + + def hasPayload: Boolean + + def payloadArity: Int + + def getPayload(index: Int): A + + def size: Int + + def foreach[U](f: A => U): Unit + + def subsetOf(that: SetNode[A], shift: Int): Boolean + + def copy(): SetNode[A] + + def filterImpl(pred: A => Boolean, flipped: Boolean): SetNode[A] + + def diff(that: SetNode[A], shift: Int): SetNode[A] + + def concat(that: SetNode[A], shift: Int): SetNode[A] + + def foreachWithHash(f: (A, Int) => Unit): Unit + + def foreachWithHashWhile(f: (A, Int) => Boolean): Boolean +} + +private final class BitmapIndexedSetNode[A]( + var dataMap: Int, + var nodeMap: Int, + var content: Array[Any], + var originalHashes: Array[Int], + var size: Int, + var cachedJavaKeySetHashCode: Int) extends SetNode[A] { + + import Node._ + import SetNode._ + + /* + assert(checkInvariantContentIsWellTyped()) + assert(checkInvariantSubNodesAreCompacted()) + + private final def checkInvariantSubNodesAreCompacted(): Boolean = + new SetIterator[A](this).size - payloadArity >= 2 * nodeArity + + private final def checkInvariantContentIsWellTyped(): Boolean = { + val predicate1 = TupleLength * payloadArity + nodeArity == content.length + + val predicate2 = Range(0, TupleLength * payloadArity) + .forall(i => content(i).isInstanceOf[SetNode[_]] == false) + + val predicate3 = Range(TupleLength * payloadArity, content.length) + .forall(i => content(i).isInstanceOf[SetNode[_]] == true) + + predicate1 && predicate2 && predicate3 + } + */ + + def getPayload(index: Int): A = content(index).asInstanceOf[A] + + override def getHash(index: Int): Int = originalHashes(index) + + def getNode(index: Int): SetNode[A] = content(content.length - 1 - index).asInstanceOf[SetNode[A]] + + def contains(element: A, originalHash: Int, elementHash: Int, shift: Int): Boolean = { + val mask = maskFrom(elementHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + return originalHashes(index) == originalHash && element == this.getPayload(index) + } + + if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + return this.getNode(index).contains(element, originalHash, elementHash, shift + BitPartitionSize) + } + + false + } + + def updated(element: A, originalHash: Int, elementHash: Int, shift: Int): BitmapIndexedSetNode[A] = { + val mask = maskFrom(elementHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val element0 = this.getPayload(index) + + if (element0.asInstanceOf[AnyRef] eq element.asInstanceOf[AnyRef]) { + return this + } else { + val element0UnimprovedHash = getHash(index) + val element0Hash = improve(element0UnimprovedHash) + if (originalHash == element0UnimprovedHash && element0 == element) { + return this + } else { + val subNodeNew = mergeTwoKeyValPairs(element0, element0UnimprovedHash, element0Hash, element, originalHash, elementHash, shift + BitPartitionSize) + return copyAndMigrateFromInlineToNode(bitpos, element0Hash, subNodeNew) + } + } + } + if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + + val subNodeNew = subNode.updated(element, originalHash, elementHash, shift + BitPartitionSize) + if (subNode eq subNodeNew) { + return this + } else { + return copyAndSetNode(bitpos, subNode, subNodeNew) + } + } + + copyAndInsertValue(bitpos, element, originalHash, elementHash) + } + /** A variant of `updated` which performs shallow mutations on the root (`this`), and if possible, on immediately + * descendant child nodes (only one level beneath `this`) + * + * The caller should pass a bitmap of child nodes of this node, which this method may mutate. + * If this method may mutate a child node, then if the updated value is located in that child node, it will + * be shallowly mutated (its children will not be mutated). + * + * If instead this method may not mutate the child node in which the to-be-updated value is located, then + * that child will be updated immutably, but the result will be mutably re-inserted as a child of this node. + * + * @param key the key to update + * @param originalHash key.## + * @param keyHash the improved hash + * @param shallowlyMutableNodeMap bitmap of child nodes of this node, which can be shallowly mutated + * during the call to this method + * + * @return Int which is the bitwise OR of shallowlyMutableNodeMap and any freshly created nodes, which will be + * available for mutations in subsequent calls. + */ + def updateWithShallowMutations(element: A, originalHash: Int, elementHash: Int, shift: Int, shallowlyMutableNodeMap: Int): Int = { + val mask = maskFrom(elementHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val element0 = getPayload(index) + val element0UnimprovedHash = getHash(index) + if (element0UnimprovedHash == originalHash && element0 == element) { + shallowlyMutableNodeMap + } else { + val element0Hash = improve(element0UnimprovedHash) + val subNodeNew = mergeTwoKeyValPairs(element0, element0UnimprovedHash, element0Hash, element, originalHash, elementHash, shift + BitPartitionSize) + migrateFromInlineToNodeInPlace(bitpos, element0Hash, subNodeNew) + shallowlyMutableNodeMap | bitpos + } + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + val subNodeSize = subNode.size + val subNodeCachedJavaKeySetHashCode = subNode.cachedJavaKeySetHashCode + + var returnNodeMap = shallowlyMutableNodeMap + + val subNodeNew: SetNode[A] = subNode match { + case subNodeBm: BitmapIndexedSetNode[A] if (bitpos & shallowlyMutableNodeMap) != 0 => + subNodeBm.updateWithShallowMutations(element, originalHash, elementHash, shift + BitPartitionSize, 0) + subNodeBm + case _ => + val subNodeNew = subNode.updated(element, originalHash, elementHash, shift + BitPartitionSize) + if (subNodeNew ne subNode) { + returnNodeMap |= bitpos + } + subNodeNew + } + + this.content(this.content.length - 1 - this.nodeIndex(bitpos)) = subNodeNew + this.size = this.size - subNodeSize + subNodeNew.size + this.cachedJavaKeySetHashCode = this.cachedJavaKeySetHashCode - subNodeCachedJavaKeySetHashCode + subNodeNew.cachedJavaKeySetHashCode + returnNodeMap + } else { + val dataIx = dataIndex(bitpos) + val idx = dataIx + + val src = this.content + val dst = new Array[Any](src.length + TupleLength) + + // copy 'src' and insert 2 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + dst(idx) = element + arraycopy(src, idx, dst, idx + TupleLength, src.length - idx) + + val dstHashes = insertElement(originalHashes, dataIx, originalHash) + + this.dataMap |= bitpos + this.content = dst + this.originalHashes = dstHashes + this.size += 1 + this.cachedJavaKeySetHashCode += elementHash + shallowlyMutableNodeMap + } + } + + + def removed(element: A, originalHash: Int, elementHash: Int, shift: Int): BitmapIndexedSetNode[A] = { + val mask = maskFrom(elementHash, shift) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val element0 = this.getPayload(index) + + if (element0 == element) { + if (this.payloadArity == 2 && this.nodeArity == 0) { + /* + * Create new node with remaining pair. The new node will a) either become the new root + * returned, or b) unwrapped and inlined during returning. + */ + val newDataMap = if (shift == 0) (dataMap ^ bitpos) else bitposFrom(maskFrom(elementHash, 0)) + if (index == 0) + return new BitmapIndexedSetNode[A](newDataMap, 0, Array(getPayload(1)), Array(originalHashes(1)), size - 1, improve(originalHashes(1))) + else + return new BitmapIndexedSetNode[A](newDataMap, 0, Array(getPayload(0)), Array(originalHashes(0)), size - 1, improve(originalHashes(0))) + } + else return copyAndRemoveValue(bitpos, elementHash) + } else return this + } + + if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + + val subNodeNew = subNode.removed(element, originalHash, elementHash, shift + BitPartitionSize) + + if (subNodeNew eq subNode) return this + + // cache just in case subNodeNew is a hashCollision node, in which in which case a little arithmetic is avoided + // in Vector#length + val subNodeNewSize = subNodeNew.size + + if (subNodeNewSize == 1) { + if (this.size == subNode.size) { + // subNode is the only child (no other data or node children of `this` exist) + // escalate (singleton or empty) result + return subNodeNew.asInstanceOf[BitmapIndexedSetNode[A]] + } else { + // inline value (move to front) + return copyAndMigrateFromNodeToInline(bitpos, elementHash, subNode, subNodeNew) + } + } else if (subNodeNewSize > 1) { + // modify current node (set replacement node) + return copyAndSetNode(bitpos, subNode, subNodeNew) + } + } + + this + } + /** Variant of `removed` which will perform mutation on only the top-level node (`this`), rather than return a new + * node + * + * Should only be called on root nodes, because shift is assumed to be 0 + * + * @param element the element to remove + * @param originalHash the original hash of `element` + * @param elementHash the improved hash of `element` + */ + def removeWithShallowMutations(element: A, originalHash: Int, elementHash: Int): this.type = { + val mask = maskFrom(elementHash, 0) + val bitpos = bitposFrom(mask) + + if ((dataMap & bitpos) != 0) { + val index = indexFrom(dataMap, mask, bitpos) + val element0 = this.getPayload(index) + + if (element0 == element) { + if (this.payloadArity == 2 && this.nodeArity == 0) { + val newDataMap = dataMap ^ bitpos + if (index == 0) { + val newContent = Array[Any](getPayload(1)) + val newOriginalHashes = Array(originalHashes(1)) + val newCachedJavaKeySetHashCode = improve(getHash(1)) + this.content = newContent + this.originalHashes = newOriginalHashes + this.cachedJavaKeySetHashCode = newCachedJavaKeySetHashCode + } else { + val newContent = Array[Any](getPayload(0)) + val newOriginalHashes = Array(originalHashes(0)) + val newCachedJavaKeySetHashCode = improve(getHash(0)) + this.content = newContent + this.originalHashes = newOriginalHashes + this.cachedJavaKeySetHashCode = newCachedJavaKeySetHashCode + } + this.dataMap = newDataMap + this.nodeMap = 0 + this.size = 1 + this + } + else { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length - TupleLength) + + arraycopy(src, 0, dst, 0, idx) + arraycopy(src, idx + TupleLength, dst, idx, src.length - idx - TupleLength) + + val dstHashes = removeElement(originalHashes, dataIx) + + this.dataMap = this.dataMap ^ bitpos + this.content = dst + this.originalHashes = dstHashes + this.size -= 1 + this.cachedJavaKeySetHashCode -= elementHash + this + } + } else this + } else if ((nodeMap & bitpos) != 0) { + val index = indexFrom(nodeMap, mask, bitpos) + val subNode = this.getNode(index) + + val subNodeNew = subNode.removed(element, originalHash, elementHash, BitPartitionSize).asInstanceOf[BitmapIndexedSetNode[A]] + + if (subNodeNew eq subNode) return this + + if (subNodeNew.size == 1) { + if (this.payloadArity == 0 && this.nodeArity == 1) { + this.dataMap = subNodeNew.dataMap + this.nodeMap = subNodeNew.nodeMap + this.content = subNodeNew.content + this.originalHashes = subNodeNew.originalHashes + this.size = subNodeNew.size + this.cachedJavaKeySetHashCode = subNodeNew.cachedJavaKeySetHashCode + this + } else { + migrateFromNodeToInlineInPlace(bitpos, originalHash, elementHash, subNode, subNodeNew) + this + } + } else { + // size must be > 1 + this.content(this.content.length - 1 - this.nodeIndex(bitpos)) = subNodeNew + this.size -= 1 + this.cachedJavaKeySetHashCode = this.cachedJavaKeySetHashCode - subNode.cachedJavaKeySetHashCode + subNodeNew.cachedJavaKeySetHashCode + this + } + } else this + } + + def mergeTwoKeyValPairs(key0: A, originalKeyHash0: Int, keyHash0: Int, key1: A, originalKeyHash1: Int, keyHash1: Int, shift: Int): SetNode[A] = { + // assert(key0 != key1) + + if (shift >= HashCodeLength) { + new HashCollisionSetNode[A](originalKeyHash0, keyHash0, Vector(key0, key1)) + } else { + val mask0 = maskFrom(keyHash0, shift) + val mask1 = maskFrom(keyHash1, shift) + + if (mask0 != mask1) { + // unique prefixes, payload fits on same level + val dataMap = bitposFrom(mask0) | bitposFrom(mask1) + val newCachedHashCode = keyHash0 + keyHash1 + + if (mask0 < mask1) { + new BitmapIndexedSetNode[A](dataMap, 0, Array(key0, key1), Array(originalKeyHash0, originalKeyHash1), 2, newCachedHashCode) + } else { + new BitmapIndexedSetNode[A](dataMap, 0, Array(key1, key0), Array(originalKeyHash1, originalKeyHash0), 2, newCachedHashCode) + } + } else { + // identical prefixes, payload must be disambiguated deeper in the trie + val nodeMap = bitposFrom(mask0) + val node = mergeTwoKeyValPairs(key0, originalKeyHash0, keyHash0, key1, originalKeyHash1, keyHash1, shift + BitPartitionSize) + + new BitmapIndexedSetNode[A](0, nodeMap, Array(node), Array.emptyIntArray, node.size, node.cachedJavaKeySetHashCode) + } + } + } + + def hasPayload: Boolean = dataMap != 0 + + def payloadArity: Int = bitCount(dataMap) + + def hasNodes: Boolean = nodeMap != 0 + + def nodeArity: Int = bitCount(nodeMap) + + def dataIndex(bitpos: Int) = bitCount(dataMap & (bitpos - 1)) + + def nodeIndex(bitpos: Int) = bitCount(nodeMap & (bitpos - 1)) + + def copyAndSetNode(bitpos: Int, oldNode: SetNode[A], newNode: SetNode[A]) = { + val idx = this.content.length - 1 - this.nodeIndex(bitpos) + + val src = this.content + val dst = new Array[Any](src.length) + + // copy 'src' and set 1 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, src.length) + dst(idx) = newNode + new BitmapIndexedSetNode[A]( + dataMap = dataMap, + nodeMap = nodeMap, + content = dst, + originalHashes = originalHashes, + size = size - oldNode.size + newNode.size, + cachedJavaKeySetHashCode = cachedJavaKeySetHashCode - oldNode.cachedJavaKeySetHashCode + newNode.cachedJavaKeySetHashCode + ) + } + + def copyAndInsertValue(bitpos: Int, key: A, originalHash: Int, elementHash: Int) = { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length + 1) + + // copy 'src' and insert 1 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + dst(idx) = key + arraycopy(src, idx, dst, idx + 1, src.length - idx) + val dstHashes = insertElement(originalHashes, dataIx, originalHash) + + new BitmapIndexedSetNode[A](dataMap | bitpos, nodeMap, dst, dstHashes, size + 1, cachedJavaKeySetHashCode + elementHash) + } + + def copyAndSetValue(bitpos: Int, key: A, originalHash: Int, elementHash: Int) = { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length) + + // copy 'src' and set 1 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, src.length) + dst(idx) = key + + new BitmapIndexedSetNode[A](dataMap | bitpos, nodeMap, dst, originalHashes, size, cachedJavaKeySetHashCode) + } + + def copyAndRemoveValue(bitpos: Int, elementHash: Int) = { + val dataIx = dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = this.content + val dst = new Array[Any](src.length - 1) + + // copy 'src' and remove 1 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + arraycopy(src, idx + 1, dst, idx, src.length - idx - 1) + val dstHashes = removeElement(originalHashes, dataIx) + new BitmapIndexedSetNode[A](dataMap ^ bitpos, nodeMap, dst, dstHashes, size - 1, cachedJavaKeySetHashCode - elementHash) + } + + def copyAndMigrateFromInlineToNode(bitpos: Int, elementHash: Int, node: SetNode[A]) = { + val dataIx = dataIndex(bitpos) + val idxOld = TupleLength * dataIx + val idxNew = this.content.length - TupleLength - nodeIndex(bitpos) + + val src = this.content + val dst = new Array[Any](src.length - 1 + 1) + + // copy 'src' and remove 1 element(s) at position 'idxOld' and + // insert 1 element(s) at position 'idxNew' + // assert(idxOld <= idxNew) + arraycopy(src, 0, dst, 0, idxOld) + arraycopy(src, idxOld + 1, dst, idxOld, idxNew - idxOld) + dst(idxNew) = node + arraycopy(src, idxNew + 1, dst, idxNew + 1, src.length - idxNew - 1) + val dstHashes = removeElement(originalHashes, dataIx) + new BitmapIndexedSetNode[A]( + dataMap = dataMap ^ bitpos, + nodeMap = nodeMap | bitpos, + content = dst, originalHashes = dstHashes, + size = size - 1 + node.size, + cachedJavaKeySetHashCode = cachedJavaKeySetHashCode - elementHash + node.cachedJavaKeySetHashCode + ) + } + /** Variant of `copyAndMigrateFromInlineToNode` which mutates `this` rather than returning a new node. + * + * Note: This method will mutate `this`, and will mutate `this.content` + * + * Mutation of `this.content` will occur as an optimization not possible in maps. Since TupleLength == 1 for sets, + * content array size does not change during inline <-> node migrations. Therefor, since we are updating in-place, + * we reuse this.content by shifting data/nodes around, rather than allocating a new array. + * + * @param bitpos the bit position of the data to migrate to node + * @param keyHash the improved hash of the element currently at `bitpos` + * @param node the node to place at `bitpos` + */ + def migrateFromInlineToNodeInPlace(bitpos: Int, keyHash: Int, node: SetNode[A]): this.type = { + val dataIx = dataIndex(bitpos) + val idxOld = TupleLength * dataIx + val idxNew = this.content.length - TupleLength - nodeIndex(bitpos) + + arraycopy(content, idxOld + TupleLength, content, idxOld, idxNew - idxOld) + content(idxNew) = node + + this.dataMap = this.dataMap ^ bitpos + this.nodeMap = this.nodeMap | bitpos + this.originalHashes = removeElement(originalHashes, dataIx) + this.size = this.size - 1 + node.size + this.cachedJavaKeySetHashCode = this.cachedJavaKeySetHashCode - keyHash + node.cachedJavaKeySetHashCode + this + } + + def copyAndMigrateFromNodeToInline(bitpos: Int, elementHash: Int, oldNode: SetNode[A], node: SetNode[A]) = { + val idxOld = this.content.length - 1 - nodeIndex(bitpos) + val dataIxNew = dataIndex(bitpos) + val idxNew = TupleLength * dataIxNew + + val src = this.content + val dst = new Array[Any](src.length - 1 + 1) + + // copy 'src' and remove 1 element(s) at position 'idxOld' and + // insert 1 element(s) at position 'idxNew' + // assert(idxOld >= idxNew) + arraycopy(src, 0, dst, 0, idxNew) + dst(idxNew) = node.getPayload(0) + arraycopy(src, idxNew, dst, idxNew + 1, idxOld - idxNew) + arraycopy(src, idxOld + 1, dst, idxOld + 1, src.length - idxOld - 1) + val hash = node.getHash(0) + val dstHashes = insertElement(originalHashes, dataIxNew, hash) + new BitmapIndexedSetNode[A]( + dataMap = dataMap | bitpos, + nodeMap = nodeMap ^ bitpos, + content = dst, + originalHashes = dstHashes, + size = size - oldNode.size + 1, + cachedJavaKeySetHashCode = cachedJavaKeySetHashCode - oldNode.cachedJavaKeySetHashCode + node.cachedJavaKeySetHashCode + ) + } + + /** Variant of `copyAndMigrateFromNodeToInline` which mutates `this` rather than returning a new node. + * + * Note: This method will mutate `this`, and will mutate `this.content` + * + * Mutation of `this.content` will occur as an optimization not possible in maps. Since TupleLength == 1 for sets, + * content array size does not change during inline <-> node migrations. Therefor, since we are updating in-place, + * we reuse this.content by shifting data/nodes around, rather than allocating a new array. + * + * @param bitpos the bit position of the node to migrate inline + * @param oldNode the node currently stored at position `bitpos` + * @param node the node containing the single element to migrate inline + */ + def migrateFromNodeToInlineInPlace(bitpos: Int, originalHash: Int, elementHash: Int, oldNode: SetNode[A], node: SetNode[A]): Unit = { + val idxOld = this.content.length - 1 - nodeIndex(bitpos) + val dataIxNew = dataIndex(bitpos) + val element = node.getPayload(0) + arraycopy(content, dataIxNew, content, dataIxNew + 1, idxOld - dataIxNew) + content(dataIxNew) = element + val hash = node.getHash(0) + val dstHashes = insertElement(originalHashes, dataIxNew, hash) + + this.dataMap = this.dataMap | bitpos + this.nodeMap = this.nodeMap ^ bitpos + this.originalHashes = dstHashes + this.size = this.size - oldNode.size + 1 + this.cachedJavaKeySetHashCode = this.cachedJavaKeySetHashCode - oldNode.cachedJavaKeySetHashCode + node.cachedJavaKeySetHashCode + } + + def foreach[U](f: A => U): Unit = { + val thisPayloadArity = payloadArity + var i = 0 + while (i < thisPayloadArity) { + f(getPayload(i)) + i += 1 + } + + val thisNodeArity = nodeArity + var j = 0 + while (j < thisNodeArity) { + getNode(j).foreach(f) + j += 1 + } + } + + def subsetOf(that: SetNode[A], shift: Int): Boolean = if (this eq that) true else that match { + case _: HashCollisionSetNode[A] => false + case node: BitmapIndexedSetNode[A] => + val thisBitmap = this.dataMap | this.nodeMap + val nodeBitmap = node.dataMap | node.nodeMap + + if ((thisBitmap | nodeBitmap) != nodeBitmap) + return false + + var bitmap = thisBitmap & nodeBitmap + var bitsToSkip = numberOfTrailingZeros(bitmap) + + var isValidSubset = true + while (isValidSubset && bitsToSkip < HashCodeLength) { + val bitpos = bitposFrom(bitsToSkip) + + isValidSubset = + if ((this.dataMap & bitpos) != 0) { + if ((node.dataMap & bitpos) != 0) { + // Data x Data + val payload0 = this.getPayload(indexFrom(this.dataMap, bitpos)) + val payload1 = node.getPayload(indexFrom(node.dataMap, bitpos)) + payload0 == payload1 + } else { + // Data x Node + val thisDataIndex = indexFrom(this.dataMap, bitpos) + val payload = this.getPayload(thisDataIndex) + val subNode = that.getNode(indexFrom(node.nodeMap, bitpos)) + val elementUnimprovedHash = getHash(thisDataIndex) + val elementHash = improve(elementUnimprovedHash) + subNode.contains(payload, elementUnimprovedHash, elementHash, shift + BitPartitionSize) + } + } else { + // Node x Node + val subNode0 = this.getNode(indexFrom(this.nodeMap, bitpos)) + val subNode1 = node.getNode(indexFrom(node.nodeMap, bitpos)) + subNode0.subsetOf(subNode1, shift + BitPartitionSize) + } + + val newBitmap = bitmap ^ bitpos + bitmap = newBitmap + bitsToSkip = numberOfTrailingZeros(newBitmap) + } + isValidSubset + } + + override def filterImpl(pred: A => Boolean, flipped: Boolean): BitmapIndexedSetNode[A] = { + if (size == 0) this + else if (size == 1) { + if (pred(getPayload(0)) != flipped) this else SetNode.empty + } else if (nodeMap == 0) { + // Performance optimization for nodes of depth 1: + // + // this node has no "node" children, all children are inlined data elems, therefor logic is significantly simpler + // approach: + // * traverse the content array, accumulating in `newDataMap: Int` any bit positions of keys which pass the filter + // * (bitCount(newDataMap) * TupleLength) tells us the new content array and originalHashes array size, so now perform allocations + // * traverse the content array once more, placing each passing element (according to `newDatamap`) in the new content and originalHashes arrays + // + // note: + // * this optimization significantly improves performance of not only small trees, but also larger trees, since + // even non-root nodes are affected by this improvement, and large trees will consist of many nodes as + // descendants + // + val minimumIndex: Int = Integer.numberOfTrailingZeros(dataMap) + val maximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(dataMap) + + var newDataMap = 0 + var newCachedHashCode = 0 + var dataIndex = 0 + + var i = minimumIndex + + while(i < maximumIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & dataMap) != 0) { + val payload = getPayload(dataIndex) + val passed = pred(payload) != flipped + + if (passed) { + newDataMap |= bitpos + newCachedHashCode += improve(getHash(dataIndex)) + } + + dataIndex += 1 + } + + i += 1 + } + + if (newDataMap == 0) { + SetNode.empty + } else if (newDataMap == dataMap) { + this + } else { + val newSize = Integer.bitCount(newDataMap) + val newContent = new Array[Any](newSize) + val newOriginalHashCodes = new Array[Int](newSize) + val newMaximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(newDataMap) + + var j = Integer.numberOfTrailingZeros(newDataMap) + + var newDataIndex = 0 + + while (j < newMaximumIndex) { + val bitpos = bitposFrom(j) + if ((bitpos & newDataMap) != 0) { + val oldIndex = indexFrom(dataMap, bitpos) + newContent(newDataIndex) = content(oldIndex) + newOriginalHashCodes(newDataIndex) = originalHashes(oldIndex) + newDataIndex += 1 + } + j += 1 + } + + new BitmapIndexedSetNode(newDataMap, 0, newContent, newOriginalHashCodes, newSize, newCachedHashCode) + } + } else { + val allMap = dataMap | nodeMap + val minimumIndex: Int = Integer.numberOfTrailingZeros(allMap) + val maximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(allMap) + + var oldDataPassThrough = 0 + + // bitmap of nodes which, when filtered, returned a single-element node. These must be migrated to data + var nodeMigrateToDataTargetMap = 0 + + // TODO: When filtering results in a single-elem node, simply `(A, originalHash, improvedHash)` could be returned, + // rather than a singleton node (to avoid pointlessly allocating arrays, nodes, which would just be inlined in + // the parent anyways). This would probably involve changing the return type of filterImpl to `AnyRef` which may + // return at runtime a SetNode[A], or a tuple of (A, Int, Int) + + // the queue of single-element, post-filter nodes + var nodesToMigrateToData: mutable.Queue[SetNode[A]] = null + + // bitmap of all nodes which, when filtered, returned themselves. They are passed forward to the returned node + var nodesToPassThroughMap = 0 + + // bitmap of any nodes which, after being filtered, returned a node that is not empty, but also not `eq` itself + // These are stored for later inclusion into the final `content` array + // not named `newNodesMap` (plural) to avoid confusion with `newNodeMap` (singular) + var mapOfNewNodes = 0 + // each bit in `mapOfNewNodes` corresponds to one element in this queue + var newNodes: mutable.Queue[SetNode[A]] = null + + var newDataMap = 0 + var newNodeMap = 0 + var newSize = 0 + var newCachedHashCode = 0 + + var dataIndex = 0 + var nodeIndex = 0 + + var i = minimumIndex + while (i < maximumIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & dataMap) != 0) { + val payload = getPayload(dataIndex) + val passed = pred(payload) != flipped + + if (passed) { + newDataMap |= bitpos + oldDataPassThrough |= bitpos + newSize += 1 + newCachedHashCode += improve(getHash(dataIndex)) + } + + dataIndex += 1 + } else if ((bitpos & nodeMap) != 0) { + val oldSubNode = getNode(nodeIndex) + val newSubNode = oldSubNode.filterImpl(pred, flipped) + + newSize += newSubNode.size + newCachedHashCode += newSubNode.cachedJavaKeySetHashCode + + // if (newSubNode.size == 0) do nothing (drop it) + if (newSubNode.size > 1) { + newNodeMap |= bitpos + if (oldSubNode eq newSubNode) { + nodesToPassThroughMap |= bitpos + } else { + mapOfNewNodes |= bitpos + if (newNodes eq null) { + newNodes = mutable.Queue.empty[SetNode[A] @uncheckedCaptures] + } + newNodes += newSubNode + } + } else if (newSubNode.size == 1) { + newDataMap |= bitpos + nodeMigrateToDataTargetMap |= bitpos + if (nodesToMigrateToData eq null) { + nodesToMigrateToData = mutable.Queue.empty[SetNode[A] @uncheckedCaptures] + } + nodesToMigrateToData += newSubNode + } + + nodeIndex += 1 + } + + i += 1 + } + + this.newNodeFrom( + newSize = newSize, + newDataMap = newDataMap, + newNodeMap = newNodeMap, + minimumIndex = minimumIndex, + oldDataPassThrough = oldDataPassThrough, + nodesToPassThroughMap = nodesToPassThroughMap, + nodeMigrateToDataTargetMap = nodeMigrateToDataTargetMap, + nodesToMigrateToData = nodesToMigrateToData, + mapOfNewNodes = mapOfNewNodes, + newNodes = newNodes, + newCachedHashCode = newCachedHashCode + ) + } + } + + override def diff(that: SetNode[A], shift: Int): BitmapIndexedSetNode[A] = that match { + case bm: BitmapIndexedSetNode[A] => + if (size == 0) this + else if (size == 1) { + val h = getHash(0) + if (that.contains(getPayload(0), h, improve(h), shift)) SetNode.empty else this + } else { + val allMap = dataMap | nodeMap + val minimumIndex: Int = Integer.numberOfTrailingZeros(allMap) + val maximumIndex: Int = Node.BranchingFactor - Integer.numberOfLeadingZeros(allMap) + + var oldDataPassThrough = 0 + + // bitmap of nodes which, when filtered, returned a single-element node. These must be migrated to data + var nodeMigrateToDataTargetMap = 0 + // the queue of single-element, post-filter nodes + var nodesToMigrateToData: mutable.Queue[SetNode[A]] = null + + // bitmap of all nodes which, when filtered, returned themselves. They are passed forward to the returned node + var nodesToPassThroughMap = 0 + + // bitmap of any nodes which, after being filtered, returned a node that is not empty, but also not `eq` itself + // These are stored for later inclusion into the final `content` array + // not named `newNodesMap` (plural) to avoid confusion with `newNodeMap` (singular) + var mapOfNewNodes = 0 + // each bit in `mapOfNewNodes` corresponds to one element in this queue + var newNodes: mutable.Queue[SetNode[A]] = null + + var newDataMap = 0 + var newNodeMap = 0 + var newSize = 0 + var newCachedHashCode = 0 + + var dataIndex = 0 + var nodeIndex = 0 + + var i = minimumIndex + while (i < maximumIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & dataMap) != 0) { + val payload = getPayload(dataIndex) + val originalHash = getHash(dataIndex) + val hash = improve(originalHash) + + if (!bm.contains(payload, originalHash, hash, shift)) { + newDataMap |= bitpos + oldDataPassThrough |= bitpos + newSize += 1 + newCachedHashCode += hash + } + + dataIndex += 1 + } else if ((bitpos & nodeMap) != 0) { + val oldSubNode = getNode(nodeIndex) + + val newSubNode: SetNode[A] = + if ((bitpos & bm.dataMap) != 0) { + val thatDataIndex = indexFrom(bm.dataMap, bitpos) + val thatPayload = bm.getPayload(thatDataIndex) + val thatOriginalHash = bm.getHash(thatDataIndex) + val thatHash = improve(thatOriginalHash) + oldSubNode.removed(thatPayload, thatOriginalHash, thatHash, shift + BitPartitionSize) + } else if ((bitpos & bm.nodeMap) != 0) { + oldSubNode.diff(bm.getNode(indexFrom(bm.nodeMap, bitpos)), shift + BitPartitionSize) + } else { + oldSubNode + } + + newSize += newSubNode.size + newCachedHashCode += newSubNode.cachedJavaKeySetHashCode + + // if (newSubNode.size == 0) do nothing (drop it) + if (newSubNode.size > 1) { + newNodeMap |= bitpos + if (oldSubNode eq newSubNode) { + nodesToPassThroughMap |= bitpos + } else { + mapOfNewNodes |= bitpos + if (newNodes eq null) { + newNodes = mutable.Queue.empty[SetNode[A] @uncheckedCaptures] + } + newNodes += newSubNode + } + } else if (newSubNode.size == 1) { + newDataMap |= bitpos + nodeMigrateToDataTargetMap |= bitpos + if (nodesToMigrateToData eq null) { + nodesToMigrateToData = mutable.Queue.empty[SetNode[A] @uncheckedCaptures] + } + nodesToMigrateToData += newSubNode + } + + nodeIndex += 1 + } + + i += 1 + } + this.newNodeFrom( + newSize = newSize, + newDataMap = newDataMap, + newNodeMap = newNodeMap, + minimumIndex = minimumIndex, + oldDataPassThrough = oldDataPassThrough, + nodesToPassThroughMap = nodesToPassThroughMap, + nodeMigrateToDataTargetMap = nodeMigrateToDataTargetMap, + nodesToMigrateToData = nodesToMigrateToData, + mapOfNewNodes = mapOfNewNodes, + newNodes = newNodes, + newCachedHashCode = newCachedHashCode + ) + } + case _: HashCollisionSetNode[A] => + // this branch should never happen, because HashCollisionSetNodes and BitMapIndexedSetNodes do not occur at the + // same depth + throw new RuntimeException("BitmapIndexedSetNode diff HashCollisionSetNode") + } + + /** Utility method only for use in `diff` and `filterImpl` + * + * @param newSize the size of the new SetNode + * @param newDataMap the dataMap of the new SetNode + * @param newNodeMap the nodeMap of the new SetNode + * @param minimumIndex the minimum index (in range of [0, 31]) for which there are sub-nodes or data beneath the new + * SetNode + * @param oldDataPassThrough bitmap representing all the data that are just passed from `this` to the new + * SetNode + * @param nodesToPassThroughMap bitmap representing all nodes that are just passed from `this` to the new SetNode + * @param nodeMigrateToDataTargetMap bitmap representing all positions which will now be data in the new SetNode, + * but which were nodes in `this` + * @param nodesToMigrateToData a queue (in order of child position) of single-element nodes, which will be migrated + * to data, in positions in the `nodeMigrateToDataTargetMap` + * @param mapOfNewNodes bitmap of positions of new nodes to include in the new SetNode + * @param newNodes queue in order of child position, of all new nodes to include in the new SetNode + * @param newCachedHashCode the cached java keyset hashcode of the new SetNode + */ + private[this] def newNodeFrom( + newSize: Int, + newDataMap: Int, + newNodeMap: Int, + minimumIndex: Int, + oldDataPassThrough: Int, + nodesToPassThroughMap: Int, + nodeMigrateToDataTargetMap: Int, + nodesToMigrateToData: mutable.Queue[SetNode[A]], + mapOfNewNodes: Int, + newNodes: mutable.Queue[SetNode[A]], + newCachedHashCode: Int): BitmapIndexedSetNode[A] = { + if (newSize == 0) { + SetNode.empty + } else if (newSize == size) { + this + } else { + val newDataSize = bitCount(newDataMap) + val newContentSize = newDataSize + bitCount(newNodeMap) + val newContent = new Array[Any](newContentSize) + val newOriginalHashes = new Array[Int](newDataSize) + + val newAllMap = newDataMap | newNodeMap + val maxIndex = Node.BranchingFactor - Integer.numberOfLeadingZeros(newAllMap) + + // note: We MUST start from the minimum index in the old (`this`) node, otherwise `old{Node,Data}Index` will + // not be incremented properly. Otherwise we could have started at Integer.numberOfTrailingZeroes(newAllMap) + var i = minimumIndex + + var oldDataIndex = 0 + var oldNodeIndex = 0 + + var newDataIndex = 0 + var newNodeIndex = 0 + + while (i < maxIndex) { + val bitpos = bitposFrom(i) + + if ((bitpos & oldDataPassThrough) != 0) { + newContent(newDataIndex) = getPayload(oldDataIndex) + newOriginalHashes(newDataIndex) = getHash(oldDataIndex) + newDataIndex += 1 + oldDataIndex += 1 + } else if ((bitpos & nodesToPassThroughMap) != 0) { + newContent(newContentSize - newNodeIndex - 1) = getNode(oldNodeIndex) + newNodeIndex += 1 + oldNodeIndex += 1 + } else if ((bitpos & nodeMigrateToDataTargetMap) != 0) { + // we need not check for null here. If nodeMigrateToDataTargetMap != 0, then nodesMigrateToData must not be null + val node = nodesToMigrateToData.dequeue() + newContent(newDataIndex) = node.getPayload(0) + newOriginalHashes(newDataIndex) = node.getHash(0) + newDataIndex += 1 + oldNodeIndex += 1 + } else if ((bitpos & mapOfNewNodes) != 0) { + // we need not check for null here. If mapOfNewNodes != 0, then newNodes must not be null + newContent(newContentSize - newNodeIndex - 1) = newNodes.dequeue() + newNodeIndex += 1 + oldNodeIndex += 1 + } else if ((bitpos & dataMap) != 0) { + oldDataIndex += 1 + } else if ((bitpos & nodeMap) != 0) { + oldNodeIndex += 1 + } + + i += 1 + } + + new BitmapIndexedSetNode[A](newDataMap, newNodeMap, newContent, newOriginalHashes, newSize, newCachedHashCode) + } + } + + + override def equals(that: Any): Boolean = + that match { + case node: BitmapIndexedSetNode[_] => + (this eq node) || + (this.cachedJavaKeySetHashCode == node.cachedJavaKeySetHashCode) && + (this.nodeMap == node.nodeMap) && + (this.dataMap == node.dataMap) && + (this.size == node.size) && + java.util.Arrays.equals(this.originalHashes, node.originalHashes) && + deepContentEquality(this.content, node.content, content.length) + case _ => false + } + + @`inline` private def deepContentEquality(a1: Array[Any], a2: Array[Any], length: Int): Boolean = { + if (a1 eq a2) + true + else { + var isEqual = true + var i = 0 + + while (isEqual && i < length) { + isEqual = a1(i) == a2(i) + i += 1 + } + + isEqual + } + } + + override def hashCode(): Int = + throw new UnsupportedOperationException("Trie nodes do not support hashing.") + + override def copy(): BitmapIndexedSetNode[A] = { + val contentClone = content.clone() + val contentLength = contentClone.length + var i = bitCount(dataMap) + while (i < contentLength) { + contentClone(i) = contentClone(i).asInstanceOf[SetNode[A]].copy() + i += 1 + } + new BitmapIndexedSetNode[A](dataMap, nodeMap, contentClone, originalHashes.clone(), size, cachedJavaKeySetHashCode) + } + + override def concat(that: SetNode[A], shift: Int): BitmapIndexedSetNode[A] = that match { + case bm: BitmapIndexedSetNode[A] => + if (size == 0) return bm + else if (bm.size == 0 || (bm eq this)) return this + else if (bm.size == 1) { + val originalHash = bm.getHash(0) + return this.updated(bm.getPayload(0), originalHash, improve(originalHash), shift) + } + + // if we go through the merge and the result does not differ from `this`, we can just return `this`, to improve sharing + // So, `anyChangesMadeSoFar` will be set to `true` as soon as we encounter a difference between the + // currently-being-computed result, and `this` + var anyChangesMadeSoFar = false + + // bitmap containing `1` in any position that has any descendant in either left or right, either data or node + val allMap = dataMap | bm.dataMap | nodeMap | bm.nodeMap + + // minimumIndex is inclusive -- it is the first index for which there is data or nodes + val minimumBitPos: Int = Node.bitposFrom(Integer.numberOfTrailingZeros(allMap)) + // maximumIndex is inclusive -- it is the last index for which there is data or nodes + // it could not be exclusive, because then upper bound in worst case (Node.BranchingFactor) would be out-of-bound + // of int bitposition representation + val maximumBitPos: Int = Node.bitposFrom(Node.BranchingFactor - Integer.numberOfLeadingZeros(allMap) - 1) + + var leftNodeRightNode = 0 + var leftDataRightNode = 0 + var leftNodeRightData = 0 + var leftDataOnly = 0 + var rightDataOnly = 0 + var leftNodeOnly = 0 + var rightNodeOnly = 0 + var leftDataRightDataMigrateToNode = 0 + var leftDataRightDataLeftOverwrites = 0 + + var dataToNodeMigrationTargets = 0 + + { + var bitpos = minimumBitPos + var leftIdx = 0 + var rightIdx = 0 + var finished = false + + while (!finished) { + + if ((bitpos & dataMap) != 0) { + if ((bitpos & bm.dataMap) != 0) { + if (getHash(leftIdx) == bm.getHash(rightIdx) && getPayload(leftIdx) == bm.getPayload(rightIdx)) { + leftDataRightDataLeftOverwrites |= bitpos + } else { + leftDataRightDataMigrateToNode |= bitpos + dataToNodeMigrationTargets |= Node.bitposFrom(Node.maskFrom(improve(getHash(leftIdx)), shift)) + } + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + leftDataRightNode |= bitpos + } else { + leftDataOnly |= bitpos + } + leftIdx += 1 + } else if ((bitpos & nodeMap) != 0) { + if ((bitpos & bm.dataMap) != 0) { + leftNodeRightData |= bitpos + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + leftNodeRightNode |= bitpos + } else { + leftNodeOnly |= bitpos + } + } else if ((bitpos & bm.dataMap) != 0) { + rightDataOnly |= bitpos + rightIdx += 1 + } else if ((bitpos & bm.nodeMap) != 0) { + rightNodeOnly |= bitpos + } + + if (bitpos == maximumBitPos) { + finished = true + } else { + bitpos = bitpos << 1 + } + } + } + + + val newDataMap = leftDataOnly | rightDataOnly | leftDataRightDataLeftOverwrites + + val newNodeMap = + leftNodeRightNode | + leftDataRightNode | + leftNodeRightData | + leftNodeOnly | + rightNodeOnly | + dataToNodeMigrationTargets + + + if ((newDataMap == (leftDataOnly | leftDataRightDataLeftOverwrites)) && (newNodeMap == leftNodeOnly)) { + // nothing from `bm` will make it into the result -- return early + return this + } + + val newDataSize = bitCount(newDataMap) + val newContentSize = newDataSize + bitCount(newNodeMap) + + val newContent = new Array[Any](newContentSize) + val newOriginalHashes = new Array[Int](newDataSize) + var newSize = 0 + var newCachedHashCode = 0 + + { + var leftDataIdx = 0 + var rightDataIdx = 0 + var leftNodeIdx = 0 + var rightNodeIdx = 0 + + val nextShift = shift + Node.BitPartitionSize + + var compressedDataIdx = 0 + var compressedNodeIdx = 0 + + var bitpos = minimumBitPos + var finished = false + + while (!finished) { + + if ((bitpos & leftNodeRightNode) != 0) { + val leftNode = getNode(leftNodeIdx) + val newNode = leftNode.concat(bm.getNode(rightNodeIdx), nextShift) + if (leftNode ne newNode) { + anyChangesMadeSoFar = true + } + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + rightNodeIdx += 1 + leftNodeIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + + } else if ((bitpos & leftDataRightNode) != 0) { + anyChangesMadeSoFar = true + val newNode = { + val n = bm.getNode(rightNodeIdx) + val leftPayload = getPayload(leftDataIdx) + val leftOriginalHash = getHash(leftDataIdx) + val leftImproved = improve(leftOriginalHash) + n.updated(leftPayload, leftOriginalHash, leftImproved, nextShift) + } + + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + rightNodeIdx += 1 + leftDataIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } + else if ((bitpos & leftNodeRightData) != 0) { + val newNode = { + val rightOriginalHash = bm.getHash(rightDataIdx) + val leftNode = getNode(leftNodeIdx) + val updated = leftNode.updated( + element = bm.getPayload(rightDataIdx), + originalHash = bm.getHash(rightDataIdx), + hash = improve(rightOriginalHash), + shift = nextShift + ) + if (updated ne leftNode) { + anyChangesMadeSoFar = true + } + updated + } + + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + leftNodeIdx += 1 + rightDataIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + + } else if ((bitpos & leftDataOnly) != 0) { + val originalHash = originalHashes(leftDataIdx) + newContent(compressedDataIdx) = getPayload(leftDataIdx).asInstanceOf[AnyRef] + newOriginalHashes(compressedDataIdx) = originalHash + + compressedDataIdx += 1 + leftDataIdx += 1 + newSize += 1 + newCachedHashCode += improve(originalHash) + } else if ((bitpos & rightDataOnly) != 0) { + anyChangesMadeSoFar = true + val originalHash = bm.originalHashes(rightDataIdx) + newContent(compressedDataIdx) = bm.getPayload(rightDataIdx).asInstanceOf[AnyRef] + newOriginalHashes(compressedDataIdx) = originalHash + + compressedDataIdx += 1 + rightDataIdx += 1 + newSize += 1 + newCachedHashCode += improve(originalHash) + } else if ((bitpos & leftNodeOnly) != 0) { + val newNode = getNode(leftNodeIdx) + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + leftNodeIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } else if ((bitpos & rightNodeOnly) != 0) { + anyChangesMadeSoFar = true + val newNode = bm.getNode(rightNodeIdx) + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + rightNodeIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } else if ((bitpos & leftDataRightDataMigrateToNode) != 0) { + anyChangesMadeSoFar = true + val newNode = { + val leftOriginalHash = getHash(leftDataIdx) + val rightOriginalHash = bm.getHash(rightDataIdx) + + bm.mergeTwoKeyValPairs( + getPayload(leftDataIdx), leftOriginalHash, improve(leftOriginalHash), + bm.getPayload(rightDataIdx), rightOriginalHash, improve(rightOriginalHash), + nextShift + ) + } + + newContent(newContentSize - compressedNodeIdx - 1) = newNode + compressedNodeIdx += 1 + leftDataIdx += 1 + rightDataIdx += 1 + newSize += newNode.size + newCachedHashCode += newNode.cachedJavaKeySetHashCode + } else if ((bitpos & leftDataRightDataLeftOverwrites) != 0) { + val originalHash = bm.originalHashes(rightDataIdx) + newContent(compressedDataIdx) = bm.getPayload(rightDataIdx).asInstanceOf[AnyRef] + newOriginalHashes(compressedDataIdx) = originalHash + + compressedDataIdx += 1 + rightDataIdx += 1 + newSize += 1 + newCachedHashCode += improve(originalHash) + leftDataIdx += 1 + } + + if (bitpos == maximumBitPos) { + finished = true + } else { + bitpos = bitpos << 1 + } + } + } + + if (anyChangesMadeSoFar) + new BitmapIndexedSetNode( + dataMap = newDataMap, + nodeMap = newNodeMap, + content = newContent, + originalHashes = newOriginalHashes, + size = newSize, + cachedJavaKeySetHashCode = newCachedHashCode + ) + else this + + case _ => + // should never happen -- hash collisions are never at the same level as bitmapIndexedSetNodes + throw new UnsupportedOperationException("Cannot concatenate a HashCollisionSetNode with a BitmapIndexedSetNode") + } + + override def foreachWithHash(f: (A, Int) => Unit): Unit = { + val iN = payloadArity // arity doesn't change during this operation + var i = 0 + while (i < iN) { + f(getPayload(i), getHash(i)) + i += 1 + } + + val jN = nodeArity // arity doesn't change during this operation + var j = 0 + while (j < jN) { + getNode(j).foreachWithHash(f) + j += 1 + } + } + + override def foreachWithHashWhile(f: (A, Int) => Boolean): Boolean = { + val thisPayloadArity = payloadArity + var pass = true + var i = 0 + while (i < thisPayloadArity && pass) { + pass &&= f(getPayload(i), getHash(i)) + i += 1 + } + + val thisNodeArity = nodeArity + var j = 0 + while (j < thisNodeArity && pass) { + pass &&= getNode(j).foreachWithHashWhile(f) + j += 1 + } + pass + } +} + +private final class HashCollisionSetNode[A](val originalHash: Int, val hash: Int, var content: Vector[A] @uncheckedCaptures) extends SetNode[A] { + + import Node._ + + require(content.length >= 2) + + def contains(element: A, originalHash: Int, hash: Int, shift: Int): Boolean = + this.hash == hash && content.contains(element) + + def updated(element: A, originalHash: Int, hash: Int, shift: Int): SetNode[A] = + if (this.contains(element, originalHash, hash, shift)) { + this + } else { + new HashCollisionSetNode[A](originalHash, hash, content.appended(element)) + } + + /** + * Remove an element from the hash collision node. + * + * When after deletion only one element remains, we return a bit-mapped indexed node with a + * singleton element and a hash-prefix for trie level 0. This node will be then a) either become + * the new root, or b) unwrapped and inlined deeper in the trie. + */ + def removed(element: A, originalHash: Int, hash: Int, shift: Int): SetNode[A] = + if (!this.contains(element, originalHash, hash, shift)) { + this + } else { + val updatedContent = content.filterNot(element0 => element0 == element) + // assert(updatedContent.size == content.size - 1) + + updatedContent.size match { + case 1 => new BitmapIndexedSetNode[A](bitposFrom(maskFrom(hash, 0)), 0, Array(updatedContent(0)), Array(originalHash), 1, hash) + case _ => new HashCollisionSetNode[A](originalHash, hash, updatedContent) + } + } + + def hasNodes: Boolean = false + + def nodeArity: Int = 0 + + def getNode(index: Int): SetNode[A] = + throw new IndexOutOfBoundsException("No sub-nodes present in hash-collision leaf node.") + + def hasPayload: Boolean = true + + def payloadArity: Int = content.length + + def getPayload(index: Int): A = content(index) + + override def getHash(index: Int): Int = originalHash + + def size: Int = content.length + + def foreach[U](f: A => U): Unit = { + val iter = content.iterator + while (iter.hasNext) { + f(iter.next()) + } + } + + + override def cachedJavaKeySetHashCode: Int = size * hash + + def subsetOf(that: SetNode[A], shift: Int): Boolean = if (this eq that) true else that match { + case node: HashCollisionSetNode[A] => + this.payloadArity <= node.payloadArity && this.content.forall(node.content.contains) + case _ => + false + } + + override def filterImpl(pred: A => Boolean, flipped: Boolean): SetNode[A] = { + val newContent = content.filterImpl(pred, flipped) + val newContentLength = newContent.length + if (newContentLength == 0) { + SetNode.empty + } else if (newContentLength == 1) { + new BitmapIndexedSetNode[A](bitposFrom(maskFrom(hash, 0)), 0, Array(newContent.head), Array(originalHash), 1, hash) + } else if (newContent.length == content.length) this + else new HashCollisionSetNode(originalHash, hash, newContent) + } + + override def diff(that: SetNode[A], shift: Int): SetNode[A] = + filterImpl(that.contains(_, originalHash, hash, shift), true) + + override def equals(that: Any): Boolean = + that match { + case node: HashCollisionSetNode[_] => + (this eq node) || + (this.hash == node.hash) && + (this.content.size == node.content.size) && + this.content.forall(node.content.contains) + case _ => false + } + + override def hashCode(): Int = + throw new UnsupportedOperationException("Trie nodes do not support hashing.") + + override def copy() = new HashCollisionSetNode[A](originalHash, hash, content) + + override def concat(that: SetNode[A], shift: Int): SetNode[A] = that match { + case hc: HashCollisionSetNode[A] => + if (hc eq this) { + this + } else { + var newContent: VectorBuilder[A] = null + val iter = hc.content.iterator + while (iter.hasNext) { + val nextPayload = iter.next() + if (!content.contains(nextPayload)) { + if (newContent eq null) { + newContent = new VectorBuilder() + newContent.addAll(this.content) + } + newContent.addOne(nextPayload) + } + } + if (newContent eq null) this else new HashCollisionSetNode(originalHash, hash, newContent.result()) + } + case _: BitmapIndexedSetNode[A] => + // should never happen -- hash collisions are never at the same level as bitmapIndexedSetNodes + throw new UnsupportedOperationException("Cannot concatenate a HashCollisionSetNode with a BitmapIndexedSetNode") + } + + override def foreachWithHash(f: (A, Int) => Unit): Unit = { + val iter = content.iterator + while (iter.hasNext) { + val next = iter.next() + f(next.asInstanceOf[A], originalHash) + } + } + + override def foreachWithHashWhile(f: (A, Int) => Boolean): Boolean = { + var stillGoing = true + val iter = content.iterator + while (iter.hasNext && stillGoing) { + val next = iter.next() + stillGoing &&= f(next.asInstanceOf[A], originalHash) + } + stillGoing + } +} + +private final class SetIterator[A](rootNode: SetNode[A]) + extends ChampBaseIterator[SetNode[A]](rootNode) with Iterator[A] { + + def next() = { + if (!hasNext) + throw new NoSuchElementException + + val payload = currentValueNode.getPayload(currentValueCursor) + currentValueCursor += 1 + + payload + } + +} + +private final class SetReverseIterator[A](rootNode: SetNode[A]) + extends ChampBaseReverseIterator[SetNode[A]](rootNode) with Iterator[A] { + + def next(): A = { + if (!hasNext) + throw new NoSuchElementException + + val payload = currentValueNode.getPayload(currentValueCursor) + currentValueCursor -= 1 + + payload + } + +} + +private final class SetHashIterator[A](rootNode: SetNode[A]) + extends ChampBaseIterator[SetNode[A]](rootNode) with Iterator[AnyRef] { + private[this] var hash = 0 + override def hashCode(): Int = hash + + def next(): AnyRef = { + if (!hasNext) + throw new NoSuchElementException + + hash = currentValueNode.getHash(currentValueCursor) + currentValueCursor += 1 + this + } + +} + + +/** + * $factoryInfo + * + * @define Coll `immutable.HashSet` + * @define coll immutable champ hash set + */ +@SerialVersionUID(3L) +object HashSet extends IterableFactory[HashSet] { + + @transient + private final val EmptySet = new HashSet(SetNode.empty) + + def empty[A]: HashSet[A] = + EmptySet.asInstanceOf[HashSet[A]] + + def from[A](source: collection.IterableOnce[A]^): HashSet[A] = + source match { + case hs: HashSet[A] => hs + case _ if source.knownSize == 0 => empty[A] + case _ => (newBuilder[A] ++= source).result() + } + + /** Create a new Builder which can be reused after calling `result()` without an + * intermediate call to `clear()` in order to build multiple related results. + */ + def newBuilder[A]: ReusableBuilder[A, HashSet[A]] = new HashSetBuilder +} + +/** Builder for HashSet. + * $multipleResults + */ +private[collection] final class HashSetBuilder[A] extends ReusableBuilder[A, HashSet[A]] { + import Node._ + import SetNode._ + + private def newEmptyRootNode = new BitmapIndexedSetNode[A](0, 0, Array.emptyObjectArray.asInstanceOf[Array[Any]], Array.emptyIntArray, 0, 0) + + /** The last given out HashSet as a return value of `result()`, if any, otherwise null. + * Indicates that on next add, the elements should be copied to an identical structure, before continuing + * mutations. */ + private var aliased: HashSet[A] @uncheckedCaptures = _ + + private def isAliased: Boolean = aliased != null + + /** The root node of the partially build hashmap */ + private var rootNode: BitmapIndexedSetNode[A] @uncheckedCaptures = newEmptyRootNode + + /** Inserts element `elem` into array `as` at index `ix`, shifting right the trailing elems */ + private def insertElement(as: Array[Int], ix: Int, elem: Int): Array[Int] = { + if (ix < 0) throw new ArrayIndexOutOfBoundsException + if (ix > as.length) throw new ArrayIndexOutOfBoundsException + val result = new Array[Int](as.length + 1) + arraycopy(as, 0, result, 0, ix) + result(ix) = elem + arraycopy(as, ix, result, ix + 1, as.length - ix) + result + } + + /** Inserts key-value into the bitmapIndexMapNode. Requires that this is a new key-value pair */ + private def insertValue[A1 >: A](bm: BitmapIndexedSetNode[A], bitpos: Int, key: A, originalHash: Int, keyHash: Int): Unit = { + val dataIx = bm.dataIndex(bitpos) + val idx = TupleLength * dataIx + + val src = bm.content + val dst = new Array[Any](src.length + TupleLength) + + // copy 'src' and insert 2 element(s) at position 'idx' + arraycopy(src, 0, dst, 0, idx) + dst(idx) = key + arraycopy(src, idx, dst, idx + TupleLength, src.length - idx) + + val dstHashes = insertElement(bm.originalHashes, dataIx, originalHash) + + bm.dataMap = bm.dataMap | bitpos + bm.content = dst + bm.originalHashes = dstHashes + bm.size += 1 + bm.cachedJavaKeySetHashCode += keyHash + } + + /** Mutates `bm` to replace inline data at bit position `bitpos` with updated key/value */ + private def setValue[A1 >: A](bm: BitmapIndexedSetNode[A], bitpos: Int, elem: A): Unit = { + val dataIx = bm.dataIndex(bitpos) + val idx = TupleLength * dataIx + bm.content(idx) = elem + } + + def update(setNode: SetNode[A], element: A, originalHash: Int, elementHash: Int, shift: Int): Unit = + setNode match { + case bm: BitmapIndexedSetNode[A] => + val mask = maskFrom(elementHash, shift) + val bitpos = bitposFrom(mask) + + if ((bm.dataMap & bitpos) != 0) { + val index = indexFrom(bm.dataMap, mask, bitpos) + val element0 = bm.getPayload(index) + val element0UnimprovedHash = bm.getHash(index) + + if (element0UnimprovedHash == originalHash && element0 == element) { + setValue(bm, bitpos, element0) + } else { + val element0Hash = improve(element0UnimprovedHash) + val subNodeNew = bm.mergeTwoKeyValPairs(element0, element0UnimprovedHash, element0Hash, element, originalHash, elementHash, shift + BitPartitionSize) + bm.migrateFromInlineToNodeInPlace(bitpos, element0Hash, subNodeNew) + } + } else if ((bm.nodeMap & bitpos) != 0) { + val index = indexFrom(bm.nodeMap, mask, bitpos) + val subNode = bm.getNode(index) + val beforeSize = subNode.size + val beforeHashCode = subNode.cachedJavaKeySetHashCode + update(subNode, element, originalHash, elementHash, shift + BitPartitionSize) + bm.size += subNode.size - beforeSize + bm.cachedJavaKeySetHashCode += subNode.cachedJavaKeySetHashCode - beforeHashCode + } else { + insertValue(bm, bitpos, element, originalHash, elementHash) + } + case hc: HashCollisionSetNode[A] => + val index = hc.content.indexOf(element) + if (index < 0) { + hc.content = hc.content.appended(element) + } else { + hc.content = hc.content.updated(index, element) + } + } + + /** If currently referencing aliased structure, copy elements to new mutable structure */ + private def ensureUnaliased():Unit = { + if (isAliased) copyElems() + aliased = null + } + + /** Copy elements to new mutable structure */ + private def copyElems(): Unit = { + rootNode = rootNode.copy() + } + + override def result(): HashSet[A] = + if (rootNode.size == 0) { + HashSet.empty + } else if (aliased != null) { + aliased + } else { + aliased = new HashSet(rootNode) + releaseFence() + aliased + } + + override def addOne(elem: A): this.type = { + ensureUnaliased() + val h = elem.## + val im = improve(h) + update(rootNode, elem, h, im, 0) + this + } + + override def addAll(xs: IterableOnce[A]^) = { + ensureUnaliased() + xs match { + case hm: HashSet[A] => + new ChampBaseIterator[SetNode[A]](hm.rootNode) { + while(hasNext) { + val originalHash = currentValueNode.getHash(currentValueCursor) + update( + setNode = rootNode, + element = currentValueNode.getPayload(currentValueCursor), + originalHash = originalHash, + elementHash = improve(originalHash), + shift = 0 + ) + currentValueCursor += 1 + } + }.asInstanceOf // !!! cc gets confused with representation of capture sets in invariant position + case other => + val it = other.iterator + while(it.hasNext) addOne(it.next()) + } + + this + } + + override def clear(): Unit = { + aliased = null + if (rootNode.size > 0) { + // if rootNode is empty, we will not have given it away anyways, we instead give out the reused Set.empty + rootNode = newEmptyRootNode + } + } + + private[collection] def size: Int = rootNode.size + + override def knownSize: Int = rootNode.size +} From 528c24999addbfe07461380295cbc3dc83116213 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 10:41:32 +0100 Subject: [PATCH 65/89] Add immutable IntMap and LongMap to stdlib --- .../stdlib/collection/immutable/IntMap.scala | 504 ++++++++++++++++++ .../stdlib/collection/immutable/LongMap.scala | 492 +++++++++++++++++ 2 files changed, 996 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/IntMap.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/LongMap.scala diff --git a/tests/pos-special/stdlib/collection/immutable/IntMap.scala b/tests/pos-special/stdlib/collection/immutable/IntMap.scala new file mode 100644 index 000000000000..d7077845b845 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/IntMap.scala @@ -0,0 +1,504 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package immutable + +import scala.collection.generic.{BitOperations, DefaultSerializationProxy} +import scala.collection.mutable.{Builder, ImmutableBuilder} +import scala.annotation.tailrec +import scala.annotation.unchecked.uncheckedVariance +import scala.language.implicitConversions +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** Utility class for integer maps. + */ +private[immutable] object IntMapUtils extends BitOperations.Int { + def branchMask(i: Int, j: Int) = highestOneBit(i ^ j) + + def join[T](p1: Int, t1: IntMap[T], p2: Int, t2: IntMap[T]): IntMap[T] = { + val m = branchMask(p1, p2) + val p = mask(p1, m) + if (zero(p1, m)) IntMap.Bin(p, m, t1, t2) + else IntMap.Bin(p, m, t2, t1) + } + + def bin[T](prefix: Int, mask: Int, left: IntMap[T], right: IntMap[T]): IntMap[T] = (left, right) match { + case (left, IntMap.Nil) => left + case (IntMap.Nil, right) => right + case (left, right) => IntMap.Bin(prefix, mask, left, right) + } +} + +import IntMapUtils._ + +/** A companion object for integer maps. + * + * @define Coll `IntMap` + */ +object IntMap { + def empty[T] : IntMap[T] = IntMap.Nil + + def singleton[T](key: Int, value: T): IntMap[T] = IntMap.Tip(key, value) + + def apply[T](elems: (Int, T)*): IntMap[T] = + elems.foldLeft(empty[T])((x, y) => x.updated(y._1, y._2)) + + def from[V](coll: IterableOnce[(Int, V)]^): IntMap[V] = + newBuilder[V].addAll(coll).result() + + private[immutable] case object Nil extends IntMap[Nothing] { + // Important! Without this equals method in place, an infinite + // loop from Map.equals => size => pattern-match-on-Nil => equals + // develops. Case objects and custom equality don't mix without + // careful handling. + override def equals(that : Any) = that match { + case _: this.type => true + case _: IntMap[_] => false // The only empty IntMaps are eq Nil + case _ => super.equals(that) + } + } + + private[immutable] case class Tip[+T](key: Int, value: T) extends IntMap[T]{ + def withValue[S](s: S) = + if (s.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef]) this.asInstanceOf[IntMap.Tip[S]] + else IntMap.Tip(key, s) + } + + private[immutable] case class Bin[+T](prefix: Int, mask: Int, left: IntMap[T], right: IntMap[T]) extends IntMap[T] { + def bin[S](left: IntMap[S], right: IntMap[S]): IntMap[S] = { + if ((this.left eq left) && (this.right eq right)) this.asInstanceOf[IntMap.Bin[S]] + else IntMap.Bin[S](prefix, mask, left, right) + } + } + + def newBuilder[V]: Builder[(Int, V), IntMap[V]] = + new ImmutableBuilder[(Int, V), IntMap[V]](empty) { + def addOne(elem: (Int, V)): this.type = { elems = elems + elem; this } + } + + implicit def toFactory[V](dummy: IntMap.type): Factory[(Int, V), IntMap[V]] = ToFactory.asInstanceOf[Factory[(Int, V), IntMap[V]]] + + @SerialVersionUID(3L) + private[this] object ToFactory extends Factory[(Int, AnyRef), IntMap[AnyRef]] with Serializable { + def fromSpecific(it: IterableOnce[(Int, AnyRef)]^): IntMap[AnyRef] = IntMap.from[AnyRef](it) + def newBuilder: Builder[(Int, AnyRef), IntMap[AnyRef]] = IntMap.newBuilder[AnyRef] + } + + implicit def toBuildFrom[V](factory: IntMap.type): BuildFrom[Any, (Int, V), IntMap[V]] = ToBuildFrom.asInstanceOf[BuildFrom[Any, (Int, V), IntMap[V]]] + private[this] object ToBuildFrom extends BuildFrom[Any, (Int, AnyRef), IntMap[AnyRef]] { + def fromSpecific(from: Any)(it: IterableOnce[(Int, AnyRef)]^) = IntMap.from(it) + def newBuilder(from: Any) = IntMap.newBuilder[AnyRef] + } + + implicit def iterableFactory[V]: Factory[(Int, V), IntMap[V]] = toFactory(this) + implicit def buildFromIntMap[V]: BuildFrom[IntMap[_], (Int, V), IntMap[V]] = toBuildFrom(this) +} + +// Iterator over a non-empty IntMap. +private[immutable] abstract class IntMapIterator[V, T](it: IntMap[V]) extends AbstractIterator[T] { + + // Basically this uses a simple stack to emulate conversion over the tree. However + // because we know that Ints are at least 32 bits we can have at most 32 IntMap.Bins and + // one IntMap.Tip sitting on the tree at any point. Therefore we know the maximum stack + // depth is 33 and + var index = 0 + var buffer = new Array[AnyRef](33) + + def pop = { + index -= 1 + buffer(index).asInstanceOf[IntMap[V]] + } + + def push(x: IntMap[V]): Unit = { + buffer(index) = x.asInstanceOf[AnyRef] + index += 1 + } + push(it) + + /** + * What value do we assign to a tip? + */ + def valueOf(tip: IntMap.Tip[V]): T + + def hasNext = index != 0 + @tailrec + final def next(): T = + pop match { + case IntMap.Bin(_,_, t@IntMap.Tip(_, _), right) => { + push(right) + valueOf(t) + } + case IntMap.Bin(_, _, left, right) => { + push(right) + push(left) + next() + } + case t@IntMap.Tip(_, _) => valueOf(t) + // This should never happen. We don't allow IntMap.Nil in subtrees of the IntMap + // and don't return an IntMapIterator for IntMap.Nil. + case IntMap.Nil => throw new IllegalStateException("Empty maps not allowed as subtrees") + } +} + +private[immutable] class IntMapEntryIterator[V](it: IntMap[V]) extends IntMapIterator[V, (Int, V)](it) { + def valueOf(tip: IntMap.Tip[V]) = (tip.key, tip.value) +} + +private[immutable] class IntMapValueIterator[V](it: IntMap[V]) extends IntMapIterator[V, V](it) { + def valueOf(tip: IntMap.Tip[V]) = tip.value +} + +private[immutable] class IntMapKeyIterator[V](it: IntMap[V]) extends IntMapIterator[V, Int](it) { + def valueOf(tip: IntMap.Tip[V]) = tip.key +} + +import IntMap._ + +/** Specialised immutable map structure for integer keys, based on + * [[https://ittc.ku.edu/~andygill/papers/IntMap98.pdf Fast Mergeable Integer Maps]] + * by Okasaki and Gill. Essentially a trie based on binary digits of the integers. + * + * '''Note:''' This class is as of 2.8 largely superseded by HashMap. + * + * @tparam T type of the values associated with integer keys. + * + * @define Coll `immutable.IntMap` + * @define coll immutable integer map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +sealed abstract class IntMap[+T] extends AbstractMap[Int, T] + with StrictOptimizedMapOps[Int, T, Map, IntMap[T]] + with Serializable { + + override protected def fromSpecific(coll: scala.collection.IterableOnce[(Int, T) @uncheckedVariance]^): IntMap[T] = + intMapFrom[T](coll) + protected def intMapFrom[V2](coll: scala.collection.IterableOnce[(Int, V2)]^): IntMap[V2] = { + val b = IntMap.newBuilder[V2] + b.sizeHint(coll) + b.addAll(coll) + b.result() + } + override protected def newSpecificBuilder: Builder[(Int, T), IntMap[T]] @uncheckedVariance = + new ImmutableBuilder[(Int, T), IntMap[T]](empty) { + def addOne(elem: (Int, T)): this.type = { elems = elems + elem; this } + } + + override def empty: IntMap[T] = IntMap.Nil + + override def toList = { + val buffer = new scala.collection.mutable.ListBuffer[(Int, T) @uncheckedCaptures] + foreach(buffer += _) + buffer.toList + } + + /** + * Iterator over key, value pairs of the map in unsigned order of the keys. + * + * @return an iterator over pairs of integer keys and corresponding values. + */ + def iterator: Iterator[(Int, T)] = this match { + case IntMap.Nil => Iterator.empty + case _ => new IntMapEntryIterator(this) + } + + /** + * Loops over the key, value pairs of the map in unsigned order of the keys. + */ + override final def foreach[U](f: ((Int, T)) => U): Unit = this match { + case IntMap.Bin(_, _, left, right) => { left.foreach(f); right.foreach(f) } + case IntMap.Tip(key, value) => f((key, value)) + case IntMap.Nil => + } + + override def foreachEntry[U](f: (IntMapUtils.Int, T) => U): Unit = this match { + case IntMap.Bin(_, _, left, right) => { left.foreachEntry(f); right.foreachEntry(f) } + case IntMap.Tip(key, value) => f(key, value) + case IntMap.Nil => + } + + override def keysIterator: Iterator[Int] = this match { + case IntMap.Nil => Iterator.empty + case _ => new IntMapKeyIterator(this) + } + + /** + * Loop over the keys of the map. The same as `keys.foreach(f)`, but may + * be more efficient. + * + * @param f The loop body + */ + final def foreachKey[U](f: Int => U): Unit = this match { + case IntMap.Bin(_, _, left, right) => { left.foreachKey(f); right.foreachKey(f) } + case IntMap.Tip(key, _) => f(key) + case IntMap.Nil => + } + + override def valuesIterator: Iterator[T] = this match { + case IntMap.Nil => Iterator.empty + case _ => new IntMapValueIterator(this) + } + + /** + * Loop over the values of the map. The same as `values.foreach(f)`, but may + * be more efficient. + * + * @param f The loop body + */ + final def foreachValue[U](f: T => U): Unit = this match { + case IntMap.Bin(_, _, left, right) => { left.foreachValue(f); right.foreachValue(f) } + case IntMap.Tip(_, value) => f(value) + case IntMap.Nil => + } + + override protected[this] def className = "IntMap" + + override def isEmpty = this eq IntMap.Nil + override def knownSize: Int = if (isEmpty) 0 else super.knownSize + override def filter(f: ((Int, T)) => Boolean): IntMap[T] = this match { + case IntMap.Bin(prefix, mask, left, right) => { + val (newleft, newright) = (left.filter(f), right.filter(f)) + if ((left eq newleft) && (right eq newright)) this + else bin(prefix, mask, newleft, newright) + } + case IntMap.Tip(key, value) => + if (f((key, value))) this + else IntMap.Nil + case IntMap.Nil => IntMap.Nil + } + + override def transform[S](f: (Int, T) => S): IntMap[S] = this match { + case b@IntMap.Bin(prefix, mask, left, right) => b.bin(left.transform(f), right.transform(f)) + case t@IntMap.Tip(key, value) => t.withValue(f(key, value)) + case IntMap.Nil => IntMap.Nil + } + + final override def size: Int = this match { + case IntMap.Nil => 0 + case IntMap.Tip(_, _) => 1 + case IntMap.Bin(_, _, left, right) => left.size + right.size + } + + @tailrec + final def get(key: Int): Option[T] = this match { + case IntMap.Bin(prefix, mask, left, right) => if (zero(key, mask)) left.get(key) else right.get(key) + case IntMap.Tip(key2, value) => if (key == key2) Some(value) else None + case IntMap.Nil => None + } + + @tailrec + final override def getOrElse[S >: T](key: Int, default: => S): S = this match { + case IntMap.Nil => default + case IntMap.Tip(key2, value) => if (key == key2) value else default + case IntMap.Bin(prefix, mask, left, right) => + if (zero(key, mask)) left.getOrElse(key, default) else right.getOrElse(key, default) + } + + @tailrec + final override def apply(key: Int): T = this match { + case IntMap.Bin(prefix, mask, left, right) => if (zero(key, mask)) left(key) else right(key) + case IntMap.Tip(key2, value) => if (key == key2) value else throw new IllegalArgumentException("Key not found") + case IntMap.Nil => throw new IllegalArgumentException("key not found") + } + + override def + [S >: T] (kv: (Int, S)): IntMap[S] = updated(kv._1, kv._2) + + override def updated[S >: T](key: Int, value: S): IntMap[S] = this match { + case IntMap.Bin(prefix, mask, left, right) => + if (!hasMatch(key, prefix, mask)) join(key, IntMap.Tip(key, value), prefix, this) + else if (zero(key, mask)) IntMap.Bin(prefix, mask, left.updated(key, value), right) + else IntMap.Bin(prefix, mask, left, right.updated(key, value)) + case IntMap.Tip(key2, value2) => + if (key == key2) IntMap.Tip(key, value) + else join(key, IntMap.Tip(key, value), key2, this) + case IntMap.Nil => IntMap.Tip(key, value) + } + + def map[V2](f: ((Int, T)) => (Int, V2)): IntMap[V2] = intMapFrom(new View.Map(this, f)) + + def flatMap[V2](f: ((Int, T)) => IterableOnce[(Int, V2)]): IntMap[V2] = intMapFrom(new View.FlatMap(this, f)) + + override def concat[V1 >: T](that: collection.IterableOnce[(Int, V1)]^): IntMap[V1] = + super.concat(that).asInstanceOf[IntMap[V1]] // Already has correct type but not declared as such + + override def ++ [V1 >: T](that: collection.IterableOnce[(Int, V1)]^): IntMap[V1] = concat(that) + + def collect[V2](pf: PartialFunction[(Int, T), (Int, V2)]): IntMap[V2] = + strictOptimizedCollect(IntMap.newBuilder[V2], pf) + + /** + * Updates the map, using the provided function to resolve conflicts if the key is already present. + * + * Equivalent to: + * {{{ + * this.get(key) match { + * case None => this.update(key, value) + * case Some(oldvalue) => this.update(key, f(oldvalue, value) + * } + * }}} + * + * @tparam S The supertype of values in this `LongMap`. + * @param key The key to update + * @param value The value to use if there is no conflict + * @param f The function used to resolve conflicts. + * @return The updated map. + */ + def updateWith[S >: T](key: Int, value: S, f: (T, S) => S): IntMap[S] = this match { + case IntMap.Bin(prefix, mask, left, right) => + if (!hasMatch(key, prefix, mask)) join(key, IntMap.Tip(key, value), prefix, this) + else if (zero(key, mask)) IntMap.Bin(prefix, mask, left.updateWith(key, value, f), right) + else IntMap.Bin(prefix, mask, left, right.updateWith(key, value, f)) + case IntMap.Tip(key2, value2) => + if (key == key2) IntMap.Tip(key, f(value2, value)) + else join(key, IntMap.Tip(key, value), key2, this) + case IntMap.Nil => IntMap.Tip(key, value) + } + + def removed (key: Int): IntMap[T] = this match { + case IntMap.Bin(prefix, mask, left, right) => + if (!hasMatch(key, prefix, mask)) this + else if (zero(key, mask)) bin(prefix, mask, left - key, right) + else bin(prefix, mask, left, right - key) + case IntMap.Tip(key2, _) => + if (key == key2) IntMap.Nil + else this + case IntMap.Nil => IntMap.Nil + } + + /** + * A combined transform and filter function. Returns an `IntMap` such that + * for each `(key, value)` mapping in this map, if `f(key, value) == None` + * the map contains no mapping for key, and if `f(key, value)`. + * + * @tparam S The type of the values in the resulting `LongMap`. + * @param f The transforming function. + * @return The modified map. + */ + def modifyOrRemove[S](f: (Int, T) => Option[S]): IntMap[S] = this match { + case IntMap.Bin(prefix, mask, left, right) => + val newleft = left.modifyOrRemove(f) + val newright = right.modifyOrRemove(f) + if ((left eq newleft) && (right eq newright)) this.asInstanceOf[IntMap[S]] + else bin(prefix, mask, newleft, newright) + case IntMap.Tip(key, value) => f(key, value) match { + case None => + IntMap.Nil + case Some(value2) => + //hack to preserve sharing + if (value.asInstanceOf[AnyRef] eq value2.asInstanceOf[AnyRef]) this.asInstanceOf[IntMap[S]] + else IntMap.Tip(key, value2) + } + case IntMap.Nil => + IntMap.Nil + } + + /** + * Forms a union map with that map, using the combining function to resolve conflicts. + * + * @tparam S The type of values in `that`, a supertype of values in `this`. + * @param that The map to form a union with. + * @param f The function used to resolve conflicts between two mappings. + * @return Union of `this` and `that`, with identical key conflicts resolved using the function `f`. + */ + def unionWith[S >: T](that: IntMap[S], f: (Int, S, S) => S): IntMap[S] = (this, that) match{ + case (IntMap.Bin(p1, m1, l1, r1), that@(IntMap.Bin(p2, m2, l2, r2))) => + if (shorter(m1, m2)) { + if (!hasMatch(p2, p1, m1)) join(p1, this, p2, that) + else if (zero(p2, m1)) IntMap.Bin(p1, m1, l1.unionWith(that, f), r1) + else IntMap.Bin(p1, m1, l1, r1.unionWith(that, f)) + } else if (shorter(m2, m1)){ + if (!hasMatch(p1, p2, m2)) join(p1, this, p2, that) + else if (zero(p1, m2)) IntMap.Bin(p2, m2, this.unionWith(l2, f), r2) + else IntMap.Bin(p2, m2, l2, this.unionWith(r2, f)) + } + else { + if (p1 == p2) IntMap.Bin(p1, m1, l1.unionWith(l2,f), r1.unionWith(r2, f)) + else join(p1, this, p2, that) + } + case (IntMap.Tip(key, value), x) => x.updateWith[S](key, value, (x, y) => f(key, y, x)) + case (x, IntMap.Tip(key, value)) => x.updateWith[S](key, value, (x, y) => f(key, x, y)) + case (IntMap.Nil, x) => x + case (x, IntMap.Nil) => x + } + + /** + * Forms the intersection of these two maps with a combining function. The + * resulting map is a map that has only keys present in both maps and has + * values produced from the original mappings by combining them with `f`. + * + * @tparam S The type of values in `that`. + * @tparam R The type of values in the resulting `LongMap`. + * @param that The map to intersect with. + * @param f The combining function. + * @return Intersection of `this` and `that`, with values for identical keys produced by function `f`. + */ + def intersectionWith[S, R](that: IntMap[S], f: (Int, T, S) => R): IntMap[R] = (this, that) match { + case (IntMap.Bin(p1, m1, l1, r1), that@IntMap.Bin(p2, m2, l2, r2)) => + if (shorter(m1, m2)) { + if (!hasMatch(p2, p1, m1)) IntMap.Nil + else if (zero(p2, m1)) l1.intersectionWith(that, f) + else r1.intersectionWith(that, f) + } else if (m1 == m2) bin(p1, m1, l1.intersectionWith(l2, f), r1.intersectionWith(r2, f)) + else { + if (!hasMatch(p1, p2, m2)) IntMap.Nil + else if (zero(p1, m2)) this.intersectionWith(l2, f) + else this.intersectionWith(r2, f) + } + case (IntMap.Tip(key, value), that) => that.get(key) match { + case None => IntMap.Nil + case Some(value2) => IntMap.Tip(key, f(key, value, value2)) + } + case (_, IntMap.Tip(key, value)) => this.get(key) match { + case None => IntMap.Nil + case Some(value2) => IntMap.Tip(key, f(key, value2, value)) + } + case (_, _) => IntMap.Nil + } + + /** + * Left biased intersection. Returns the map that has all the same mappings + * as this but only for keys which are present in the other map. + * + * @tparam R The type of values in `that`. + * @param that The map to intersect with. + * @return A map with all the keys both in `this` and `that`, mapped to corresponding values from `this`. + */ + def intersection[R](that: IntMap[R]): IntMap[T] = + this.intersectionWith(that, (key: Int, value: T, value2: R) => value) + + def ++[S >: T](that: IntMap[S]) = + this.unionWith[S](that, (key, x, y) => y) + + /** + * The entry with the lowest key value considered in unsigned order. + */ + @tailrec + final def firstKey: Int = this match { + case Bin(_, _, l, r) => l.firstKey + case Tip(k, v) => k + case IntMap.Nil => throw new IllegalStateException("Empty set") + } + + /** + * The entry with the highest key value considered in unsigned order. + */ + @tailrec + final def lastKey: Int = this match { + case Bin(_, _, l, r) => r.lastKey + case Tip(k, v) => k + case IntMap.Nil => throw new IllegalStateException("Empty set") + } + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(IntMap.toFactory[T](IntMap), this) +} diff --git a/tests/pos-special/stdlib/collection/immutable/LongMap.scala b/tests/pos-special/stdlib/collection/immutable/LongMap.scala new file mode 100644 index 000000000000..4abf433273f2 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/LongMap.scala @@ -0,0 +1,492 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package immutable + +import java.lang.IllegalStateException + +import scala.collection.generic.{BitOperations, DefaultSerializationProxy} +import scala.collection.mutable.{Builder, ImmutableBuilder, ListBuffer} +import scala.annotation.tailrec +import scala.annotation.unchecked.uncheckedVariance +import scala.language.implicitConversions +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** Utility class for long maps. + */ +private[immutable] object LongMapUtils extends BitOperations.Long { + def branchMask(i: Long, j: Long) = highestOneBit(i ^ j) + + def join[T](p1: Long, t1: LongMap[T], p2: Long, t2: LongMap[T]): LongMap[T] = { + val m = branchMask(p1, p2) + val p = mask(p1, m) + if (zero(p1, m)) LongMap.Bin(p, m, t1, t2) + else LongMap.Bin(p, m, t2, t1) + } + + def bin[T](prefix: Long, mask: Long, left: LongMap[T], right: LongMap[T]): LongMap[T] = (left, right) match { + case (left, LongMap.Nil) => left + case (LongMap.Nil, right) => right + case (left, right) => LongMap.Bin(prefix, mask, left, right) + } +} + +import LongMapUtils._ + +/** A companion object for long maps. + * + * @define Coll `LongMap` + */ +object LongMap { + def empty[T]: LongMap[T] = LongMap.Nil + def singleton[T](key: Long, value: T): LongMap[T] = LongMap.Tip(key, value) + def apply[T](elems: (Long, T)*): LongMap[T] = + elems.foldLeft(empty[T])((x, y) => x.updated(y._1, y._2)) + + def from[V](coll: IterableOnce[(Long, V)]^): LongMap[V] = + newBuilder[V].addAll(coll).result() + + def newBuilder[V]: Builder[(Long, V), LongMap[V]] = + new ImmutableBuilder[(Long, V), LongMap[V]](empty) { + def addOne(elem: (Long, V)): this.type = { elems = elems + elem; this } + } + + private[immutable] case object Nil extends LongMap[Nothing] { + // Important, don't remove this! See IntMap for explanation. + override def equals(that : Any) = that match { + case _: this.type => true + case _: LongMap[_] => false // The only empty LongMaps are eq Nil + case _ => super.equals(that) + } + } + + private[immutable] case class Tip[+T](key: Long, value: T) extends LongMap[T] { + def withValue[S](s: S) = + if (s.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef]) this.asInstanceOf[LongMap.Tip[S]] + else LongMap.Tip(key, s) + } + + private[immutable] case class Bin[+T](prefix: Long, mask: Long, left: LongMap[T], right: LongMap[T]) extends LongMap[T] { + def bin[S](left: LongMap[S], right: LongMap[S]): LongMap[S] = { + if ((this.left eq left) && (this.right eq right)) this.asInstanceOf[LongMap.Bin[S]] + else LongMap.Bin[S](prefix, mask, left, right) + } + } + + implicit def toFactory[V](dummy: LongMap.type): Factory[(Long, V), LongMap[V]] = ToFactory.asInstanceOf[Factory[(Long, V), LongMap[V]]] + + @SerialVersionUID(3L) + private[this] object ToFactory extends Factory[(Long, AnyRef), LongMap[AnyRef]] with Serializable { + def fromSpecific(it: IterableOnce[(Long, AnyRef)]^): LongMap[AnyRef] = LongMap.from[AnyRef](it) + def newBuilder: Builder[(Long, AnyRef), LongMap[AnyRef]] = LongMap.newBuilder[AnyRef] + } + + implicit def toBuildFrom[V](factory: LongMap.type): BuildFrom[Any, (Long, V), LongMap[V]] = ToBuildFrom.asInstanceOf[BuildFrom[Any, (Long, V), LongMap[V]]] + private[this] object ToBuildFrom extends BuildFrom[Any, (Long, AnyRef), LongMap[AnyRef]] { + def fromSpecific(from: Any)(it: IterableOnce[(Long, AnyRef)]^) = LongMap.from(it) + def newBuilder(from: Any) = LongMap.newBuilder[AnyRef] + } + + implicit def iterableFactory[V]: Factory[(Long, V), LongMap[V]] = toFactory(this) + implicit def buildFromLongMap[V]: BuildFrom[LongMap[_], (Long, V), LongMap[V]] = toBuildFrom(this) +} + +// Iterator over a non-empty LongMap. +private[immutable] abstract class LongMapIterator[V, T](it: LongMap[V]) extends AbstractIterator[T] { + + // Basically this uses a simple stack to emulate conversion over the tree. However + // because we know that Longs are only 64 bits we can have at most 64 LongMap.Bins and + // one LongMap.Tip sitting on the tree at any point. Therefore we know the maximum stack + // depth is 65 + var index = 0 + var buffer = new Array[AnyRef](65) + + def pop() = { + index -= 1 + buffer(index).asInstanceOf[LongMap[V]] + } + + def push(x: LongMap[V]): Unit = { + buffer(index) = x.asInstanceOf[AnyRef] + index += 1 + } + push(it) + + /** + * What value do we assign to a tip? + */ + def valueOf(tip: LongMap.Tip[V]): T + + def hasNext = index != 0 + @tailrec + final def next(): T = + pop() match { + case LongMap.Bin(_,_, t@LongMap.Tip(_, _), right) => { + push(right) + valueOf(t) + } + case LongMap.Bin(_, _, left, right) => { + push(right) + push(left) + next() + } + case t@LongMap.Tip(_, _) => valueOf(t) + // This should never happen. We don't allow LongMap.Nil in subtrees of the LongMap + // and don't return an LongMapIterator for LongMap.Nil. + case LongMap.Nil => throw new IllegalStateException("Empty maps not allowed as subtrees") + } +} + +private[immutable] class LongMapEntryIterator[V](it: LongMap[V]) extends LongMapIterator[V, (Long, V)](it){ + def valueOf(tip: LongMap.Tip[V]) = (tip.key, tip.value) +} + +private[immutable] class LongMapValueIterator[V](it: LongMap[V]) extends LongMapIterator[V, V](it){ + def valueOf(tip: LongMap.Tip[V]) = tip.value +} + +private[immutable] class LongMapKeyIterator[V](it: LongMap[V]) extends LongMapIterator[V, Long](it){ + def valueOf(tip: LongMap.Tip[V]) = tip.key +} + +/** + * Specialised immutable map structure for long keys, based on + * [[https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.37.5452 Fast Mergeable Long Maps]] + * by Okasaki and Gill. Essentially a trie based on binary digits of the integers. + * + * Note: This class is as of 2.8 largely superseded by HashMap. + * + * @tparam T type of the values associated with the long keys. + * + * @define Coll `immutable.LongMap` + * @define coll immutable long integer map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +sealed abstract class LongMap[+T] extends AbstractMap[Long, T] + with StrictOptimizedMapOps[Long, T, Map, LongMap[T]] + with Serializable { + + override protected def fromSpecific(coll: scala.collection.IterableOnce[(Long, T) @uncheckedVariance]^): LongMap[T] = { + //TODO should this be the default implementation of this method in StrictOptimizedIterableOps? + val b = newSpecificBuilder + b.sizeHint(coll) + b.addAll(coll) + b.result() + } + override protected def newSpecificBuilder: Builder[(Long, T), LongMap[T]] @uncheckedVariance = + new ImmutableBuilder[(Long, T), LongMap[T]](empty) { + def addOne(elem: (Long, T)): this.type = { elems = elems + elem; this } + } + + override def empty: LongMap[T] = LongMap.Nil + + override def toList = { + val buffer = new ListBuffer[(Long, T) @uncheckedCaptures] + foreach(buffer += _) + buffer.toList + } + + /** + * Iterator over key, value pairs of the map in unsigned order of the keys. + * + * @return an iterator over pairs of long keys and corresponding values. + */ + def iterator: Iterator[(Long, T)] = this match { + case LongMap.Nil => Iterator.empty + case _ => new LongMapEntryIterator(this) + } + + /** + * Loops over the key, value pairs of the map in unsigned order of the keys. + */ + override final def foreach[U](f: ((Long, T)) => U): Unit = this match { + case LongMap.Bin(_, _, left, right) => { left.foreach(f); right.foreach(f) } + case LongMap.Tip(key, value) => f((key, value)) + case LongMap.Nil => + } + + override final def foreachEntry[U](f: (Long, T) => U): Unit = this match { + case LongMap.Bin(_, _, left, right) => { left.foreachEntry(f); right.foreachEntry(f) } + case LongMap.Tip(key, value) => f(key, value) + case LongMap.Nil => + } + + override def keysIterator: Iterator[Long] = this match { + case LongMap.Nil => Iterator.empty + case _ => new LongMapKeyIterator(this) + } + + /** + * Loop over the keys of the map. The same as keys.foreach(f), but may + * be more efficient. + * + * @param f The loop body + */ + final def foreachKey[U](f: Long => U): Unit = this match { + case LongMap.Bin(_, _, left, right) => { left.foreachKey(f); right.foreachKey(f) } + case LongMap.Tip(key, _) => f(key) + case LongMap.Nil => + } + + override def valuesIterator: Iterator[T] = this match { + case LongMap.Nil => Iterator.empty + case _ => new LongMapValueIterator(this) + } + + /** + * Loop over the values of the map. The same as values.foreach(f), but may + * be more efficient. + * + * @param f The loop body + */ + final def foreachValue[U](f: T => U): Unit = this match { + case LongMap.Bin(_, _, left, right) => { left.foreachValue(f); right.foreachValue(f) } + case LongMap.Tip(_, value) => f(value) + case LongMap.Nil => + } + + override protected[this] def className = "LongMap" + + override def isEmpty = this eq LongMap.Nil + override def knownSize: Int = if (isEmpty) 0 else super.knownSize + override def filter(f: ((Long, T)) => Boolean): LongMap[T] = this match { + case LongMap.Bin(prefix, mask, left, right) => { + val (newleft, newright) = (left.filter(f), right.filter(f)) + if ((left eq newleft) && (right eq newright)) this + else bin(prefix, mask, newleft, newright) + } + case LongMap.Tip(key, value) => + if (f((key, value))) this + else LongMap.Nil + case LongMap.Nil => LongMap.Nil + } + + override def transform[S](f: (Long, T) => S): LongMap[S] = this match { + case b@LongMap.Bin(prefix, mask, left, right) => b.bin(left.transform(f), right.transform(f)) + case t@LongMap.Tip(key, value) => t.withValue(f(key, value)) + case LongMap.Nil => LongMap.Nil + } + + final override def size: Int = this match { + case LongMap.Nil => 0 + case LongMap.Tip(_, _) => 1 + case LongMap.Bin(_, _, left, right) => left.size + right.size + } + + @tailrec + final def get(key: Long): Option[T] = this match { + case LongMap.Bin(prefix, mask, left, right) => if (zero(key, mask)) left.get(key) else right.get(key) + case LongMap.Tip(key2, value) => if (key == key2) Some(value) else None + case LongMap.Nil => None + } + + @tailrec + final override def getOrElse[S >: T](key: Long, default: => S): S = this match { + case LongMap.Nil => default + case LongMap.Tip(key2, value) => if (key == key2) value else default + case LongMap.Bin(prefix, mask, left, right) => + if (zero(key, mask)) left.getOrElse(key, default) else right.getOrElse(key, default) + } + + @tailrec + final override def apply(key: Long): T = this match { + case LongMap.Bin(prefix, mask, left, right) => if (zero(key, mask)) left(key) else right(key) + case LongMap.Tip(key2, value) => if (key == key2) value else throw new IllegalArgumentException("Key not found") + case LongMap.Nil => throw new IllegalArgumentException("key not found") + } + + override def + [S >: T] (kv: (Long, S)): LongMap[S] = updated(kv._1, kv._2) + + override def updated[S >: T](key: Long, value: S): LongMap[S] = this match { + case LongMap.Bin(prefix, mask, left, right) => + if (!hasMatch(key, prefix, mask)) join(key, LongMap.Tip(key, value), prefix, this) + else if (zero(key, mask)) LongMap.Bin(prefix, mask, left.updated(key, value), right) + else LongMap.Bin(prefix, mask, left, right.updated(key, value)) + case LongMap.Tip(key2, value2) => + if (key == key2) LongMap.Tip(key, value) + else join(key, LongMap.Tip(key, value), key2, this) + case LongMap.Nil => LongMap.Tip(key, value) + } + + /** + * Updates the map, using the provided function to resolve conflicts if the key is already present. + * + * Equivalent to + * {{{ + * this.get(key) match { + * case None => this.update(key, value) + * case Some(oldvalue) => this.update(key, f(oldvalue, value) + * } + * }}} + * + * @tparam S The supertype of values in this `LongMap`. + * @param key The key to update. + * @param value The value to use if there is no conflict. + * @param f The function used to resolve conflicts. + * @return The updated map. + */ + def updateWith[S >: T](key: Long, value: S, f: (T, S) => S): LongMap[S] = this match { + case LongMap.Bin(prefix, mask, left, right) => + if (!hasMatch(key, prefix, mask)) join(key, LongMap.Tip(key, value), prefix, this) + else if (zero(key, mask)) LongMap.Bin(prefix, mask, left.updateWith(key, value, f), right) + else LongMap.Bin(prefix, mask, left, right.updateWith(key, value, f)) + case LongMap.Tip(key2, value2) => + if (key == key2) LongMap.Tip(key, f(value2, value)) + else join(key, LongMap.Tip(key, value), key2, this) + case LongMap.Nil => LongMap.Tip(key, value) + } + + def removed(key: Long): LongMap[T] = this match { + case LongMap.Bin(prefix, mask, left, right) => + if (!hasMatch(key, prefix, mask)) this + else if (zero(key, mask)) bin(prefix, mask, left - key, right) + else bin(prefix, mask, left, right - key) + case LongMap.Tip(key2, _) => + if (key == key2) LongMap.Nil + else this + case LongMap.Nil => LongMap.Nil + } + + /** + * A combined transform and filter function. Returns an `LongMap` such that + * for each `(key, value)` mapping in this map, if `f(key, value) == None` + * the map contains no mapping for key, and if `f(key, value)`. + * + * @tparam S The type of the values in the resulting `LongMap`. + * @param f The transforming function. + * @return The modified map. + */ + def modifyOrRemove[S](f: (Long, T) => Option[S]): LongMap[S] = this match { + case LongMap.Bin(prefix, mask, left, right) => { + val newleft = left.modifyOrRemove(f) + val newright = right.modifyOrRemove(f) + if ((left eq newleft) && (right eq newright)) this.asInstanceOf[LongMap[S]] + else bin(prefix, mask, newleft, newright) + } + case LongMap.Tip(key, value) => f(key, value) match { + case None => LongMap.Nil + case Some(value2) => + //hack to preserve sharing + if (value.asInstanceOf[AnyRef] eq value2.asInstanceOf[AnyRef]) this.asInstanceOf[LongMap[S]] + else LongMap.Tip(key, value2) + } + case LongMap.Nil => LongMap.Nil + } + + /** + * Forms a union map with that map, using the combining function to resolve conflicts. + * + * @tparam S The type of values in `that`, a supertype of values in `this`. + * @param that The map to form a union with. + * @param f The function used to resolve conflicts between two mappings. + * @return Union of `this` and `that`, with identical key conflicts resolved using the function `f`. + */ + def unionWith[S >: T](that: LongMap[S], f: (Long, S, S) => S): LongMap[S] = (this, that) match{ + case (LongMap.Bin(p1, m1, l1, r1), that@(LongMap.Bin(p2, m2, l2, r2))) => + if (shorter(m1, m2)) { + if (!hasMatch(p2, p1, m1)) join(p1, this, p2, that) + else if (zero(p2, m1)) LongMap.Bin(p1, m1, l1.unionWith(that, f), r1) + else LongMap.Bin(p1, m1, l1, r1.unionWith(that, f)) + } else if (shorter(m2, m1)){ + if (!hasMatch(p1, p2, m2)) join(p1, this, p2, that) + else if (zero(p1, m2)) LongMap.Bin(p2, m2, this.unionWith(l2, f), r2) + else LongMap.Bin(p2, m2, l2, this.unionWith(r2, f)) + } + else { + if (p1 == p2) LongMap.Bin(p1, m1, l1.unionWith(l2,f), r1.unionWith(r2, f)) + else join(p1, this, p2, that) + } + case (LongMap.Tip(key, value), x) => x.updateWith(key, value, (x, y) => f(key, y, x)) + case (x, LongMap.Tip(key, value)) => x.updateWith[S](key, value, (x, y) => f(key, x, y)) + case (LongMap.Nil, x) => x + case (x, LongMap.Nil) => x + } + + /** + * Forms the intersection of these two maps with a combining function. The + * resulting map is a map that has only keys present in both maps and has + * values produced from the original mappings by combining them with `f`. + * + * @tparam S The type of values in `that`. + * @tparam R The type of values in the resulting `LongMap`. + * @param that The map to intersect with. + * @param f The combining function. + * @return Intersection of `this` and `that`, with values for identical keys produced by function `f`. + */ + def intersectionWith[S, R](that: LongMap[S], f: (Long, T, S) => R): LongMap[R] = (this, that) match { + case (LongMap.Bin(p1, m1, l1, r1), that@LongMap.Bin(p2, m2, l2, r2)) => + if (shorter(m1, m2)) { + if (!hasMatch(p2, p1, m1)) LongMap.Nil + else if (zero(p2, m1)) l1.intersectionWith(that, f) + else r1.intersectionWith(that, f) + } else if (m1 == m2) bin(p1, m1, l1.intersectionWith(l2, f), r1.intersectionWith(r2, f)) + else { + if (!hasMatch(p1, p2, m2)) LongMap.Nil + else if (zero(p1, m2)) this.intersectionWith(l2, f) + else this.intersectionWith(r2, f) + } + case (LongMap.Tip(key, value), that) => that.get(key) match { + case None => LongMap.Nil + case Some(value2) => LongMap.Tip(key, f(key, value, value2)) + } + case (_, LongMap.Tip(key, value)) => this.get(key) match { + case None => LongMap.Nil + case Some(value2) => LongMap.Tip(key, f(key, value2, value)) + } + case (_, _) => LongMap.Nil + } + + /** + * Left biased intersection. Returns the map that has all the same mappings as this but only for keys + * which are present in the other map. + * + * @tparam R The type of values in `that`. + * @param that The map to intersect with. + * @return A map with all the keys both in `this` and `that`, mapped to corresponding values from `this`. + */ + def intersection[R](that: LongMap[R]): LongMap[T] = + this.intersectionWith(that, (key: Long, value: T, value2: R) => value) + + def ++[S >: T](that: LongMap[S]) = + this.unionWith[S](that, (key, x, y) => y) + + @tailrec + final def firstKey: Long = this match { + case LongMap.Bin(_, _, l, r) => l.firstKey + case LongMap.Tip(k, v) => k + case LongMap.Nil => throw new IllegalStateException("Empty set") + } + + @tailrec + final def lastKey: Long = this match { + case LongMap.Bin(_, _, l, r) => r.lastKey + case LongMap.Tip(k , v) => k + case LongMap.Nil => throw new IllegalStateException("Empty set") + } + + def map[V2](f: ((Long, T)) => (Long, V2)): LongMap[V2] = LongMap.from(new View.Map(coll, f)) + + def flatMap[V2](f: ((Long, T)) => IterableOnce[(Long, V2)]): LongMap[V2] = LongMap.from(new View.FlatMap(coll, f)) + + override def concat[V1 >: T](that: scala.collection.IterableOnce[(Long, V1)]^): LongMap[V1] = + super.concat(that).asInstanceOf[LongMap[V1]] // Already has correct type but not declared as such + + override def ++ [V1 >: T](that: scala.collection.IterableOnce[(Long, V1)]^): LongMap[V1] = concat(that) + + def collect[V2](pf: PartialFunction[(Long, T), (Long, V2)]): LongMap[V2] = + strictOptimizedCollect(LongMap.newBuilder[V2], pf) + + protected[this] def writeReplace(): AnyRef = new DefaultSerializationProxy(LongMap.toFactory[T](LongMap), this) +} From 02c62814dc7f13c683f42a8eb26aed687ef132c2 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 10:47:00 +0100 Subject: [PATCH 66/89] Add immutable ListSet and ListMap to stdlib --- .../stdlib/collection/immutable/ListMap.scala | 373 ++++++++++++++++++ .../stdlib/collection/immutable/ListSet.scala | 140 +++++++ 2 files changed, 513 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/ListMap.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/ListSet.scala diff --git a/tests/pos-special/stdlib/collection/immutable/ListMap.scala b/tests/pos-special/stdlib/collection/immutable/ListMap.scala new file mode 100644 index 000000000000..c5000d785144 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/ListMap.scala @@ -0,0 +1,373 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.tailrec +import scala.collection.mutable.ReusableBuilder +import scala.collection.generic.DefaultSerializable +import scala.runtime.Statics.releaseFence +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** + * This class implements immutable maps using a list-based data structure. List map iterators and + * traversal methods visit key-value pairs in the order they were first inserted. + * + * Entries are stored internally in reversed insertion order, which means the newest key is at the + * head of the list. As such, methods such as `head` and `tail` are O(n), while `last` and `init` + * are O(1). Other operations, such as inserting or removing entries, are also O(n), which makes + * this collection suitable only for a small number of elements. + * + * Instances of `ListMap` represent empty maps; they can be either created by calling the + * constructor directly, or by applying the function `ListMap.empty`. + * + * @tparam K the type of the keys contained in this list map + * @tparam V the type of the values associated with the keys + * + * @define Coll ListMap + * @define coll list map + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +sealed class ListMap[K, +V] + extends AbstractMap[K, V] + with SeqMap[K, V] + with StrictOptimizedMapOps[K, V, ListMap, ListMap[K, V]] + with MapFactoryDefaults[K, V, ListMap, Iterable] + with DefaultSerializable { + + override def mapFactory: MapFactory[ListMap] = ListMap + + override def size: Int = 0 + + override def isEmpty: Boolean = true + + override def knownSize: Int = 0 + def get(key: K): Option[V] = None + + def updated[V1 >: V](key: K, value: V1): ListMap[K, V1] = new ListMap.Node[K, V1](key, value, this) + + def removed(key: K): ListMap[K, V] = this + + def iterator: Iterator[(K, V)] = { + var curr: ListMap[K, V] = this + var res: List[(K, V)] = Nil + while (curr.nonEmpty) { + res = (curr.key, curr.value) :: res + curr = curr.next + } + res.iterator + } + + override def keys: Iterable[K] = { + var curr: ListMap[K, V] = this + var res: List[K] = Nil + while (curr.nonEmpty) { + res = curr.key :: res + curr = curr.next + } + res + } + + override def hashCode(): Int = { + if (isEmpty) MurmurHash3.emptyMapHash + else { + // Can't efficiently override foreachEntry directly in ListMap because it would need to preserve iteration + // order be reversing the list first. But mapHash is symmetric so the reversed order is fine here. + val _reversed = new immutable.AbstractMap[K, V] { + override def isEmpty: Boolean = ListMap.this.isEmpty + override def removed(key: K): Map[K, V] = ListMap.this.removed(key) + override def updated[V1 >: V](key: K, value: V1): Map[K, V1] = ListMap.this.updated(key, value) + override def get(key: K): Option[V] = ListMap.this.get(key) + override def iterator: Iterator[(K, V)] = ListMap.this.iterator + override def foreachEntry[U](f: (K, V) => U): Unit = { + var curr: ListMap[K, V] = ListMap.this + while (curr.nonEmpty) { + f(curr.key, curr.value) + curr = curr.next + } + } + } + MurmurHash3.mapHash(_reversed) + } + } + + private[immutable] def key: K = throw new NoSuchElementException("key of empty map") + private[immutable] def value: V = throw new NoSuchElementException("value of empty map") + private[immutable] def next: ListMap[K, V] = throw new NoSuchElementException("next of empty map") + + override def foldRight[Z](z: Z)(op: ((K, V), Z) => Z): Z = ListMap.foldRightInternal(this, z, op) + override protected[this] def className = "ListMap" + +} + +/** + * $factoryInfo + * + * Note that each element insertion takes O(n) time, which means that creating a list map with + * n elements will take O(n^2^) time. This makes the builder suitable only for a small number of + * elements. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#list-maps "Scala's Collection Library overview"]] + * section on `List Maps` for more information. + * @define Coll ListMap + * @define coll list map + */ +@SerialVersionUID(3L) +object ListMap extends MapFactory[ListMap] { + /** + * Represents an entry in the `ListMap`. + */ + private[immutable] final class Node[K, V]( + override private[immutable] val key: K, + private[immutable] var _value: V @uncheckedCaptures, + private[immutable] var _init: ListMap[K, V] @uncheckedCaptures + ) extends ListMap[K, V] { + releaseFence() + + override private[immutable] def value: V = _value + + override def size: Int = sizeInternal(this, 0) + + @tailrec private[this] def sizeInternal(cur: ListMap[K, V], acc: Int): Int = + if (cur.isEmpty) acc + else sizeInternal(cur.next, acc + 1) + + override def isEmpty: Boolean = false + + override def knownSize: Int = -1 + + @throws[NoSuchElementException] + override def apply(k: K): V = applyInternal(this, k) + + @tailrec private[this] def applyInternal(cur: ListMap[K, V], k: K): V = + if (cur.isEmpty) throw new NoSuchElementException("key not found: " + k) + else if (k == cur.key) cur.value + else applyInternal(cur.next, k) + + override def get(k: K): Option[V] = getInternal(this, k) + + @tailrec private[this] def getInternal(cur: ListMap[K, V], k: K): Option[V] = + if (cur.isEmpty) None + else if (k == cur.key) Some(cur.value) + else getInternal(cur.next, k) + + override def contains(k: K): Boolean = containsInternal(this, k) + + @tailrec private[this] def containsInternal(cur: ListMap[K, V], k: K): Boolean = + if (cur.isEmpty) false + else if (k == cur.key) true + else containsInternal(cur.next, k) + + override def updated[V1 >: V](k: K, v: V1): ListMap[K, V1] = { + + var index = -1 // the index (in reverse) where the key to update exists, if it is found + var found = false // true if the key is found int he map + var isDifferent = false // true if the key was found and the values are different + + { + var curr: ListMap[K, V] = this + + while (curr.nonEmpty && !found) { + if (k == curr.key) { + found = true + isDifferent = v.asInstanceOf[AnyRef] ne curr.value.asInstanceOf[AnyRef] + } + index += 1 + curr = curr.init + } + } + + if (found) { + if (isDifferent) { + var newHead: ListMap.Node[K, V1] = null + var prev: ListMap.Node[K, V1] = null + var curr: ListMap[K, V1] = this + var i = 0 + while (i < index) { + val temp = new ListMap.Node(curr.key, curr.value, null) + if (prev ne null) { + prev._init = temp + } + prev = temp + curr = curr.init + if (newHead eq null) { + newHead = prev + } + i += 1 + } + val newNode = new ListMap.Node(curr.key, v, curr.init) + if (prev ne null) { + prev._init = newNode + } + releaseFence() + if (newHead eq null) newNode else newHead + } else { + this + } + } else { + new ListMap.Node(k, v, this) + } + } + + @tailrec private[this] def removeInternal(k: K, cur: ListMap[K, V], acc: List[ListMap[K, V]]): ListMap[K, V] = + if (cur.isEmpty) acc.last + else if (k == cur.key) acc.foldLeft(cur.next) { (t, h) => new Node(h.key, h.value, t) } + else removeInternal(k, cur.next, cur :: acc) + + override def removed(k: K): ListMap[K, V] = removeInternal(k, this, Nil) + + override private[immutable] def next: ListMap[K, V] = _init + + override def last: (K, V) = (key, value) + override def init: ListMap[K, V] = next + + } + + def empty[K, V]: ListMap[K, V] = EmptyListMap.asInstanceOf[ListMap[K, V]] + + private object EmptyListMap extends ListMap[Any, Nothing] + + def from[K, V](it: collection.IterableOnce[(K, V)]^): ListMap[K, V] = + it match { + case lm: ListMap[K, V] => lm + case lhm: collection.mutable.LinkedHashMap[K, V] => + // by directly iterating through LinkedHashMap entries, we save creating intermediate tuples for each + // key-value pair + var current: ListMap[K, V] = empty[K, V] + var firstEntry = lhm._firstEntry + while (firstEntry ne null) { + current = new Node(firstEntry.key, firstEntry.value, current) + firstEntry = firstEntry.later + } + current + case _: collection.Map[K, V] | _: collection.MapView[K, V] => + // when creating from a map, we need not handle duplicate keys, so we can just append each key-value to the end + var current: ListMap[K, V] = empty[K, V] + val iter = it.iterator + while (iter.hasNext) { + val (k, v) = iter.next() + current = new Node(k, v, current) + } + current + + case _ => (newBuilder[K, V] ++= it).result() + } + + /** Returns a new ListMap builder + * + * The implementation safely handles additions after `result()` without calling `clear()` + * + * @tparam K the map key type + * @tparam V the map value type + */ + def newBuilder[K, V]: ReusableBuilder[(K, V), ListMap[K, V]] = new ListMapBuilder[K, V] + + @tailrec private def foldRightInternal[K, V, Z](map: ListMap[K, V], prevValue: Z, op: ((K, V), Z) => Z): Z = { + if (map.isEmpty) prevValue + else foldRightInternal(map.init, op(map.last, prevValue), op) + } +} + +/** Builder for ListMap. + * $multipleResults + */ +private[immutable] final class ListMapBuilder[K, V] extends mutable.ReusableBuilder[(K, V), ListMap[K, V]] { + private[this] var isAliased: Boolean = false + private[this] var underlying: ListMap[K, V] @uncheckedCaptures = ListMap.empty + + override def clear(): Unit = { + underlying = ListMap.empty + isAliased = false + } + + override def result(): ListMap[K, V] = { + isAliased = true + releaseFence() + underlying + } + + override def addOne(elem: (K, V)): this.type = addOne(elem._1, elem._2) + + @tailrec + private[this] def insertValueAtKeyReturnFound(m: ListMap[K, V], key: K, value: V): Boolean = m match { + case n: ListMap.Node[K, V] => + if (n.key == key) { + n._value = value + true + } else { + insertValueAtKeyReturnFound(n.init, key, value) + } + case _ => false + } + + def addOne(key: K, value: V): this.type = { + if (isAliased) { + underlying = underlying.updated(key, value) + } else { + if (!insertValueAtKeyReturnFound(underlying, key, value)) { + underlying = new ListMap.Node(key, value, underlying) + } + } + this + } + override def addAll(xs: IterableOnce[(K, V)]^): this.type = { + if (isAliased) { + super.addAll(xs) + } else if (underlying.nonEmpty) { + xs match { + case m: collection.Map[K, V] => + // if it is a map, then its keys will not collide with themselves. + // therefor we only need to check the already-existing elements for collisions. + // No need to check the entire list + + val iter = m.iterator + var newUnderlying = underlying + while (iter.hasNext) { + val next = iter.next() + if (!insertValueAtKeyReturnFound(underlying, next._1, next._2)) { + newUnderlying = new ListMap.Node[K, V](next._1, next._2, newUnderlying) + } + } + underlying = newUnderlying + this + + case _ => + super.addAll(xs) + } + } else xs match { + case lhm: collection.mutable.LinkedHashMap[K, V] => + // special-casing LinkedHashMap avoids creating of Iterator and tuples for each key-value + var firstEntry = lhm._firstEntry + while (firstEntry ne null) { + underlying = new ListMap.Node(firstEntry.key, firstEntry.value, underlying) + firstEntry = firstEntry.later + } + this + + case _: collection.Map[K, V] | _: collection.MapView[K, V] => + val iter = xs.iterator + while (iter.hasNext) { + val (k, v) = iter.next() + underlying = new ListMap.Node(k, v, underlying) + } + + this + case _ => + super.addAll(xs) + } + } +} diff --git a/tests/pos-special/stdlib/collection/immutable/ListSet.scala b/tests/pos-special/stdlib/collection/immutable/ListSet.scala new file mode 100644 index 000000000000..719abd78e1e6 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/ListSet.scala @@ -0,0 +1,140 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import mutable.{Builder, ImmutableBuilder} +import scala.annotation.tailrec +import scala.collection.generic.DefaultSerializable +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** + * This class implements immutable sets using a list-based data structure. List set iterators and + * traversal methods visit elements in the order they were first inserted. + * + * Elements are stored internally in reversed insertion order, which means the newest element is at + * the head of the list. As such, methods such as `head` and `tail` are O(n), while `last` and + * `init` are O(1). Other operations, such as inserting or removing entries, are also O(n), which + * makes this collection suitable only for a small number of elements. + * + * Instances of `ListSet` represent empty sets; they can be either created by calling the + * constructor directly, or by applying the function `ListSet.empty`. + * + * @tparam A the type of the elements contained in this list set + * + * @define Coll ListSet + * @define coll list set + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +sealed class ListSet[A] + extends AbstractSet[A] + with StrictOptimizedSetOps[A, ListSet, ListSet[A]] + with IterableFactoryDefaults[A, ListSet] + with DefaultSerializable { + + override protected[this] def className: String = "ListSet" + + override def size: Int = 0 + override def knownSize: Int = 0 + override def isEmpty: Boolean = true + + def contains(elem: A): Boolean = false + + def incl(elem: A): ListSet[A] = new Node(elem) + def excl(elem: A): ListSet[A] = this + + def iterator: scala.collection.Iterator[A] = { + var curr: ListSet[A] = this + var res: List[A] = Nil + while (!curr.isEmpty) { + res = curr.elem :: res + curr = curr.next + } + res.iterator + } + + protected def elem: A = throw new NoSuchElementException("elem of empty set") + protected def next: ListSet[A] = throw new NoSuchElementException("next of empty set") + + override def iterableFactory: IterableFactory[ListSet] = ListSet + + /** + * Represents an entry in the `ListSet`. + */ + protected class Node(override protected val elem: A) extends ListSet[A] { + + override def size = sizeInternal(this, 0) + override def knownSize: Int = -1 + @tailrec private[this] def sizeInternal(n: ListSet[A], acc: Int): Int = + if (n.isEmpty) acc + else sizeInternal(n.next, acc + 1) + + override def isEmpty: Boolean = false + + override def contains(e: A): Boolean = containsInternal(this, e) + + @tailrec private[this] def containsInternal(n: ListSet[A], e: A): Boolean = + !n.isEmpty && (n.elem == e || containsInternal(n.next, e)) + + override def incl(e: A): ListSet[A] = if (contains(e)) this else new Node(e) + + override def excl(e: A): ListSet[A] = removeInternal(e, this, Nil) + + @tailrec private[this] def removeInternal(k: A, cur: ListSet[A], acc: List[ListSet[A]]): ListSet[A] = + if (cur.isEmpty) acc.last + else if (k == cur.elem) acc.foldLeft(cur.next)((t, h) => new t.Node(h.elem)) + else removeInternal(k, cur.next, cur :: acc) + + override protected def next: ListSet[A] = ListSet.this + + override def last: A = elem + + override def init: ListSet[A] = next + } +} + +/** + * $factoryInfo + * + * Note that each element insertion takes O(n) time, which means that creating a list set with + * n elements will take O(n^2^) time. This makes the builder suitable only for a small number of + * elements. + * + * @define Coll ListSet + * @define coll list set + */ +@SerialVersionUID(3L) +object ListSet extends IterableFactory[ListSet] { + + def from[E](it: scala.collection.IterableOnce[E]^): ListSet[E] = + it match { + case ls: ListSet[E] => ls + case _ if it.knownSize == 0 => empty[E] + case _ => (newBuilder[E] ++= it).result() + } + + private object EmptyListSet extends ListSet[Any] { + override def knownSize: Int = 0 + } + private[collection] def emptyInstance: ListSet[Any] = EmptyListSet + + def empty[A]: ListSet[A] = EmptyListSet.asInstanceOf[ListSet[A]] + + def newBuilder[A]: Builder[A, ListSet[A]] = + new ImmutableBuilder[A, ListSet[A]](empty) { + def addOne(elem: A): this.type = { elems = elems + elem; this } + } +} From 2cb34e54f15ae01bcfc11fef5a89d848c3fa2c49 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 10:53:40 +0100 Subject: [PATCH 67/89] Add immutable Map to stdlib --- .../stdlib/collection/immutable/HashMap.scala | 2 +- .../stdlib/collection/immutable/Map.scala | 694 ++++++++++++++++++ 2 files changed, 695 insertions(+), 1 deletion(-) create mode 100644 tests/pos-special/stdlib/collection/immutable/Map.scala diff --git a/tests/pos-special/stdlib/collection/immutable/HashMap.scala b/tests/pos-special/stdlib/collection/immutable/HashMap.scala index d2f144baa934..c364924db3a3 100644 --- a/tests/pos-special/stdlib/collection/immutable/HashMap.scala +++ b/tests/pos-special/stdlib/collection/immutable/HashMap.scala @@ -386,7 +386,7 @@ final class HashMap[K, +V] private[immutable] (private[immutable] val rootNode: else new HashMap(newRootNode) } - override def removedAll(keys: IterableOnce[K]): HashMap[K, V] = { + override def removedAll(keys: IterableOnce[K]^): HashMap[K, V] = { if (isEmpty) { this } else { diff --git a/tests/pos-special/stdlib/collection/immutable/Map.scala b/tests/pos-special/stdlib/collection/immutable/Map.scala new file mode 100644 index 000000000000..6daad829bf55 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/Map.scala @@ -0,0 +1,694 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.unchecked.uncheckedVariance +import scala.collection.generic.DefaultSerializable +import scala.collection.immutable.Map.Map4 +import scala.collection.mutable.{Builder, ReusableBuilder} +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** Base type of immutable Maps */ +trait Map[K, +V] + extends Iterable[(K, V)] + with collection.Map[K, V] + with MapOps[K, V, Map, Map[K, V]] + with MapFactoryDefaults[K, V, Map, Iterable] { + + override def mapFactory: scala.collection.MapFactory[Map] = Map + + override final def toMap[K2, V2](implicit ev: (K, V) <:< (K2, V2)): Map[K2, V2] = this.asInstanceOf[Map[K2, V2]] + + /** The same map with a given default function. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefault`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d the function mapping keys to values, used for non-present keys + * @return a wrapper of the map with a default value + */ + def withDefault[V1 >: V](d: K -> V1): Map[K, V1] = new Map.WithDefault[K, V1](this, d) + + /** The same map with a given default value. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefaultValue`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d default value used for non-present keys + * @return a wrapper of the map with a default value + */ + def withDefaultValue[V1 >: V](d: V1): Map[K, V1] = new Map.WithDefault[K, V1](this, _ => d) +} + +/** Base trait of immutable Maps implementations + * + * @define coll immutable map + * @define Coll `immutable.Map` + */ +trait MapOps[K, +V, +CC[X, +Y] <: MapOps[X, Y, CC, _], +C <: MapOps[K, V, CC, C]] + extends IterableOps[(K, V), Iterable, C] + with collection.MapOps[K, V, CC, C] { + + protected def coll: C with CC[K, V] + + /** Removes a key from this map, returning a new map. + * + * @param key the key to be removed + * @return a new map without a binding for ''key'' + */ + def removed(key: K): C + + /** Alias for `removed` */ + @`inline` final def - (key: K): C = removed(key) + + @deprecated("Use -- with an explicit collection", "2.13.0") + def - (key1: K, key2: K, keys: K*): C = removed(key1).removed(key2).removedAll(keys) + + /** Creates a new $coll from this $coll by removing all elements of another + * collection. + * + * $willForceEvaluation + * + * @param keys the collection containing the removed elements. + * @return a new $coll that contains all elements of the current $coll + * except one less occurrence of each of the elements of `elems`. + */ + def removedAll(keys: IterableOnce[K]^): C = keys.iterator.foldLeft[C](coll)(_ - _) + + /** Alias for `removedAll` */ + @`inline` final override def -- (keys: IterableOnce[K]^): C = removedAll(keys) + + /** Creates a new map obtained by updating this map with a given key/value pair. + * @param key the key + * @param value the value + * @tparam V1 the type of the added value + * @return A new map with the new key/value mapping added to this map. + */ + def updated[V1 >: V](key: K, value: V1): CC[K, V1] + + /** + * Update a mapping for the specified key and its current optionally-mapped value + * (`Some` if there is current mapping, `None` if not). + * + * If the remapping function returns `Some(v)`, the mapping is updated with the new value `v`. + * If the remapping function returns `None`, the mapping is removed (or remains absent if initially absent). + * If the function itself throws an exception, the exception is rethrown, and the current mapping is left unchanged. + * + * @param key the key value + * @param remappingFunction a partial function that receives current optionally-mapped value and return a new mapping + * @return A new map with the updated mapping with the key + */ + def updatedWith[V1 >: V](key: K)(remappingFunction: Option[V] => Option[V1]): CC[K,V1] = { + val previousValue = this.get(key) + remappingFunction(previousValue) match { + case None => previousValue.fold(coll)(_ => this.removed(key).coll) + case Some(nextValue) => + if (previousValue.exists(_.asInstanceOf[AnyRef] eq nextValue.asInstanceOf[AnyRef])) coll + else coll.updated(key, nextValue) + } + } + + /** + * Alias for `updated` + * + * @param kv the key/value pair. + * @tparam V1 the type of the value in the key/value pair. + * @return A new map with the new binding added to this map. + */ + override def + [V1 >: V](kv: (K, V1)): CC[K, V1] = updated(kv._1, kv._2) + + /** This function transforms all the values of mappings contained + * in this map with function `f`. + * + * @param f A function over keys and values + * @return the updated map + */ + def transform[W](f: (K, V) => W): CC[K, W] = map { case (k, v) => (k, f(k, v)) } + + override def keySet: Set[K] = new ImmutableKeySet + + /** The implementation class of the set returned by `keySet` */ + protected class ImmutableKeySet extends AbstractSet[K] with GenKeySet with DefaultSerializable { + def incl(elem: K): Set[K] = if (this(elem)) this else empty ++ this + elem + def excl(elem: K): Set[K] = if (this(elem)) empty ++ this - elem else this + } + +} + +trait StrictOptimizedMapOps[K, +V, +CC[X, +Y] <: MapOps[X, Y, CC, _], +C <: MapOps[K, V, CC, C]] + extends MapOps[K, V, CC, C] + with collection.StrictOptimizedMapOps[K, V, CC, C] + with StrictOptimizedIterableOps[(K, V), Iterable, C] { + + override def concat [V1 >: V](that: collection.IterableOnce[(K, V1)]^): CC[K, V1] = { + var result: CC[K, V1] = coll + val it = that.iterator + while (it.hasNext) result = result + it.next() + result + } +} + + +/** + * $factoryInfo + * @define coll immutable map + * @define Coll `immutable.Map` + */ +@SerialVersionUID(3L) +object Map extends MapFactory[Map] { + + @SerialVersionUID(3L) + class WithDefault[K, +V](val underlying: Map[K, V], val defaultValue: K -> V) + extends AbstractMap[K, V] + with MapOps[K, V, Map, WithDefault[K, V]] with Serializable { + + def get(key: K): Option[V] = underlying.get(key) + + override def default(key: K): V = defaultValue(key) + + override def iterableFactory: IterableFactory[Iterable] = underlying.iterableFactory + + def iterator: Iterator[(K, V)] = underlying.iterator + + override def isEmpty: Boolean = underlying.isEmpty + + override def mapFactory: MapFactory[Map] = underlying.mapFactory + + override def concat [V2 >: V](xs: collection.IterableOnce[(K, V2)]^): WithDefault[K, V2] = + new WithDefault(underlying.concat(xs), defaultValue) + + def removed(key: K): WithDefault[K, V] = new WithDefault[K, V](underlying.removed(key), defaultValue) + + def updated[V1 >: V](key: K, value: V1): WithDefault[K, V1] = + new WithDefault[K, V1](underlying.updated(key, value), defaultValue) + + override def empty: WithDefault[K, V] = new WithDefault[K, V](underlying.empty, defaultValue) + + override protected def fromSpecific(coll: collection.IterableOnce[(K, V) @uncheckedVariance]^): WithDefault[K, V] = + new WithDefault[K, V](mapFactory.from(coll), defaultValue) + + override protected def newSpecificBuilder: Builder[(K, V), WithDefault[K, V]] @uncheckedVariance = + Map.newBuilder.mapResult((p: Map[K, V]) => new WithDefault[K, V](p, defaultValue)) + } + + def empty[K, V]: Map[K, V] = EmptyMap.asInstanceOf[Map[K, V]] + + def from[K, V](it: collection.IterableOnce[(K, V)]^): Map[K, V] = + it match { + case it: Iterable[_] if it.isEmpty => empty[K, V] + case m: Map[K, V] => m + case _ => (newBuilder[K, V] ++= it).result() + } + + def newBuilder[K, V]: Builder[(K, V), Map[K, V]] = new MapBuilderImpl + + @SerialVersionUID(3L) + private object EmptyMap extends AbstractMap[Any, Nothing] with Serializable { + override def size: Int = 0 + override def knownSize: Int = 0 + override def isEmpty: Boolean = true + override def apply(key: Any) = throw new NoSuchElementException("key not found: " + key) + override def contains(key: Any) = false + def get(key: Any): Option[Nothing] = None + override def getOrElse [V1](key: Any, default: => V1): V1 = default + def iterator: Iterator[(Any, Nothing)] = Iterator.empty + override def keysIterator: Iterator[Any] = Iterator.empty + override def valuesIterator: Iterator[Nothing] = Iterator.empty + def updated [V1] (key: Any, value: V1): Map[Any, V1] = new Map1(key, value) + def removed(key: Any): Map[Any, Nothing] = this + override def concat[V2 >: Nothing](suffix: IterableOnce[(Any, V2)]^): Map[Any, V2] = suffix match { + case m: immutable.Map[Any, V2] => m + case _ => super.concat(suffix) + } + } + + @SerialVersionUID(3L) + final class Map1[K, +V](key1: K, value1: V) extends AbstractMap[K, V] with StrictOptimizedIterableOps[(K, V), Iterable, Map[K, V]] with Serializable { + override def size: Int = 1 + override def knownSize: Int = 1 + override def isEmpty: Boolean = false + override def apply(key: K): V = if (key == key1) value1 else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K): Boolean = key == key1 + def get(key: K): Option[V] = + if (key == key1) Some(value1) else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 else default + def iterator: Iterator[(K, V)] = Iterator.single((key1, value1)) + override def keysIterator: Iterator[K] = Iterator.single(key1) + override def valuesIterator: Iterator[V] = Iterator.single(value1) + def updated[V1 >: V](key: K, value: V1): Map[K, V1] = + if (key == key1) new Map1(key1, value) + else new Map2(key1, value1, key, value) + def removed(key: K): Map[K, V] = + if (key == key1) Map.empty else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)) + } + override def exists(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) + override def forall(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) + override protected[collection] def filterImpl(pred: ((K, V)) => Boolean, isFlipped: Boolean): Map[K, V] = + if (pred((key1, value1)) != isFlipped) this else Map.empty + override def transform[W](f: (K, V) => W): Map[K, W] = { + val walue1 = f(key1, value1) + if (walue1.asInstanceOf[AnyRef] eq value1.asInstanceOf[AnyRef]) this.asInstanceOf[Map[K, W]] + else new Map1(key1, walue1) + } + override def hashCode(): Int = { + import scala.util.hashing.MurmurHash3 + var a, b = 0 + val N = 1 + var c = 1 + + var h = MurmurHash3.tuple2Hash(key1, value1) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.mapSeed + h = MurmurHash3.mix(h, a) + h = MurmurHash3.mix(h, b) + h = MurmurHash3.mixLast(h, c) + MurmurHash3.finalizeHash(h, N) + } + } + + @SerialVersionUID(3L) + final class Map2[K, +V](key1: K, value1: V, key2: K, value2: V) extends AbstractMap[K, V] with StrictOptimizedIterableOps[(K, V), Iterable, Map[K, V]] with Serializable { + override def size: Int = 2 + override def knownSize: Int = 2 + override def isEmpty: Boolean = false + override def apply(key: K): V = + if (key == key1) value1 + else if (key == key2) value2 + else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K): Boolean = (key == key1) || (key == key2) + def get(key: K): Option[V] = + if (key == key1) Some(value1) + else if (key == key2) Some(value2) + else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 + else if (key == key2) value2 + else default + def iterator: Iterator[(K, V)] = new Map2Iterator[(K, V)] { + override protected def nextResult(k: K, v: V): (K, V) = (k, v) + } + override def keysIterator: Iterator[K] = new Map2Iterator[K] { + override protected def nextResult(k: K, v: V): K = k + } + override def valuesIterator: Iterator[V] = new Map2Iterator[V] { + override protected def nextResult(k: K, v: V): V = v + } + + private abstract class Map2Iterator[A] extends AbstractIterator[A], Pure { + private[this] var i = 0 + override def hasNext: Boolean = i < 2 + override def next(): A = { + val result = i match { + case 0 => nextResult(key1, value1) + case 1 => nextResult(key2, value2) + case _ => Iterator.empty.next() + } + i += 1 + result + } + override def drop(n: Int): Iterator[A] = { i += n; this } + protected def nextResult(k: K, v: V @uncheckedVariance): A + } + def updated[V1 >: V](key: K, value: V1): Map[K, V1] = + if (key == key1) new Map2(key1, value, key2, value2) + else if (key == key2) new Map2(key1, value1, key2, value) + else new Map3(key1, value1, key2, value2, key, value) + def removed(key: K): Map[K, V] = + if (key == key1) new Map1(key2, value2) + else if (key == key2) new Map1(key1, value1) + else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)); f((key2, value2)) + } + override def exists(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) || p((key2, value2)) + override def forall(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) && p((key2, value2)) + override protected[collection] def filterImpl(pred: ((K, V)) => Boolean, isFlipped: Boolean): Map[K, V] = { + var k1 = null.asInstanceOf[K] + var v1 = null.asInstanceOf[V] + var n = 0 + if (pred((key1, value1)) != isFlipped) { {k1 = key1; v1 = value1}; n += 1} + if (pred((key2, value2)) != isFlipped) { if (n == 0) {k1 = key2; v1 = value2}; n += 1} + + n match { + case 0 => Map.empty + case 1 => new Map1(k1, v1) + case 2 => this + } + } + override def transform[W](f: (K, V) => W): Map[K, W] = { + val walue1 = f(key1, value1) + val walue2 = f(key2, value2) + if ((walue1.asInstanceOf[AnyRef] eq value1.asInstanceOf[AnyRef]) && + (walue2.asInstanceOf[AnyRef] eq value2.asInstanceOf[AnyRef])) this.asInstanceOf[Map[K, W]] + else new Map2(key1, walue1, key2, walue2) + } + override def hashCode(): Int = { + import scala.util.hashing.MurmurHash3 + var a, b = 0 + val N = 2 + var c = 1 + + var h = MurmurHash3.tuple2Hash(key1, value1) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.tuple2Hash(key2, value2) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.mapSeed + h = MurmurHash3.mix(h, a) + h = MurmurHash3.mix(h, b) + h = MurmurHash3.mixLast(h, c) + MurmurHash3.finalizeHash(h, N) + } + } + + @SerialVersionUID(3L) + class Map3[K, +V](key1: K, value1: V, key2: K, value2: V, key3: K, value3: V) extends AbstractMap[K, V] with StrictOptimizedIterableOps[(K, V), Iterable, Map[K, V]] with Serializable { + override def size: Int = 3 + override def knownSize: Int = 3 + override def isEmpty: Boolean = false + override def apply(key: K): V = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K): Boolean = (key == key1) || (key == key2) || (key == key3) + def get(key: K): Option[V] = + if (key == key1) Some(value1) + else if (key == key2) Some(value2) + else if (key == key3) Some(value3) + else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else default + def iterator: Iterator[(K, V)] = new Map3Iterator[(K, V)] { + override protected def nextResult(k: K, v: V): (K, V) = (k, v) + } + override def keysIterator: Iterator[K] = new Map3Iterator[K] { + override protected def nextResult(k: K, v: V): K = k + } + override def valuesIterator: Iterator[V] = new Map3Iterator[V] { + override protected def nextResult(k: K, v: V): V = v + } + + private abstract class Map3Iterator[A] extends AbstractIterator[A], Pure { + private[this] var i = 0 + override def hasNext: Boolean = i < 3 + override def next(): A = { + val result = i match { + case 0 => nextResult(key1, value1) + case 1 => nextResult(key2, value2) + case 2 => nextResult(key3, value3) + case _ => Iterator.empty.next() + } + i += 1 + result + } + override def drop(n: Int): Iterator[A] = { i += n; this } + protected def nextResult(k: K, v: V @uncheckedVariance): A + } + def updated[V1 >: V](key: K, value: V1): Map[K, V1] = + if (key == key1) new Map3(key1, value, key2, value2, key3, value3) + else if (key == key2) new Map3(key1, value1, key2, value, key3, value3) + else if (key == key3) new Map3(key1, value1, key2, value2, key3, value) + else new Map4(key1, value1, key2, value2, key3, value3, key, value) + def removed(key: K): Map[K, V] = + if (key == key1) new Map2(key2, value2, key3, value3) + else if (key == key2) new Map2(key1, value1, key3, value3) + else if (key == key3) new Map2(key1, value1, key2, value2) + else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)); f((key2, value2)); f((key3, value3)) + } + override def exists(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) || p((key2, value2)) || p((key3, value3)) + override def forall(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) && p((key2, value2)) && p((key3, value3)) + override protected[collection] def filterImpl(pred: ((K, V)) => Boolean, isFlipped: Boolean): Map[K, V] = { + var k1, k2 = null.asInstanceOf[K] + var v1, v2 = null.asInstanceOf[V] + var n = 0 + if (pred((key1, value1)) != isFlipped) { { k1 = key1; v1 = value1 }; n += 1} + if (pred((key2, value2)) != isFlipped) { if (n == 0) { k1 = key2; v1 = value2 } else { k2 = key2; v2 = value2 }; n += 1} + if (pred((key3, value3)) != isFlipped) { if (n == 0) { k1 = key3; v1 = value3 } else if (n == 1) { k2 = key3; v2 = value3 }; n += 1} + + n match { + case 0 => Map.empty + case 1 => new Map1(k1, v1) + case 2 => new Map2(k1, v1, k2, v2) + case 3 => this + } + } + override def transform[W](f: (K, V) => W): Map[K, W] = { + val walue1 = f(key1, value1) + val walue2 = f(key2, value2) + val walue3 = f(key3, value3) + if ((walue1.asInstanceOf[AnyRef] eq value1.asInstanceOf[AnyRef]) && + (walue2.asInstanceOf[AnyRef] eq value2.asInstanceOf[AnyRef]) && + (walue3.asInstanceOf[AnyRef] eq value3.asInstanceOf[AnyRef])) this.asInstanceOf[Map[K, W]] + else new Map3(key1, walue1, key2, walue2, key3, walue3) + } + override def hashCode(): Int = { + import scala.util.hashing.MurmurHash3 + var a, b = 0 + val N = 3 + var c = 1 + + var h = MurmurHash3.tuple2Hash(key1, value1) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.tuple2Hash(key2, value2) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.tuple2Hash(key3, value3) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.mapSeed + h = MurmurHash3.mix(h, a) + h = MurmurHash3.mix(h, b) + h = MurmurHash3.mixLast(h, c) + MurmurHash3.finalizeHash(h, N) + } + } + + @SerialVersionUID(3L) + final class Map4[K, +V](key1: K, value1: V, key2: K, value2: V, key3: K, value3: V, key4: K, value4: V) + extends AbstractMap[K, V] with StrictOptimizedIterableOps[(K, V), Iterable, Map[K, V]] with Serializable { + + override def size: Int = 4 + override def knownSize: Int = 4 + override def isEmpty: Boolean = false + override def apply(key: K): V = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else if (key == key4) value4 + else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K): Boolean = (key == key1) || (key == key2) || (key == key3) || (key == key4) + def get(key: K): Option[V] = + if (key == key1) Some(value1) + else if (key == key2) Some(value2) + else if (key == key3) Some(value3) + else if (key == key4) Some(value4) + else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else if (key == key4) value4 + else default + def iterator: Iterator[(K, V)] = new Map4Iterator[(K, V)] { + override protected def nextResult(k: K, v: V): (K, V) = (k, v) + } + override def keysIterator: Iterator[K] = new Map4Iterator[K] { + override protected def nextResult(k: K, v: V): K = k + } + override def valuesIterator: Iterator[V] = new Map4Iterator[V] { + override protected def nextResult(k: K, v: V): V = v + } + + private abstract class Map4Iterator[A] extends AbstractIterator[A], Pure { + private[this] var i = 0 + override def hasNext: Boolean = i < 4 + override def next(): A = { + val result = i match { + case 0 => nextResult(key1, value1) + case 1 => nextResult(key2, value2) + case 2 => nextResult(key3, value3) + case 3 => nextResult(key4, value4) + case _ => Iterator.empty.next() + } + i += 1 + result + } + override def drop(n: Int): Iterator[A] = { i += n; this } + protected def nextResult(k: K, v: V @uncheckedVariance): A + } + def updated[V1 >: V](key: K, value: V1): Map[K, V1] = + if (key == key1) new Map4(key1, value, key2, value2, key3, value3, key4, value4) + else if (key == key2) new Map4(key1, value1, key2, value, key3, value3, key4, value4) + else if (key == key3) new Map4(key1, value1, key2, value2, key3, value, key4, value4) + else if (key == key4) new Map4(key1, value1, key2, value2, key3, value3, key4, value) + else HashMap.empty[K, V1].updated(key1,value1).updated(key2, value2).updated(key3, value3).updated(key4, value4).updated(key, value) + def removed(key: K): Map[K, V] = + if (key == key1) new Map3(key2, value2, key3, value3, key4, value4) + else if (key == key2) new Map3(key1, value1, key3, value3, key4, value4) + else if (key == key3) new Map3(key1, value1, key2, value2, key4, value4) + else if (key == key4) new Map3(key1, value1, key2, value2, key3, value3) + else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)); f((key2, value2)); f((key3, value3)); f((key4, value4)) + } + override def exists(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) || p((key2, value2)) || p((key3, value3)) || p((key4, value4)) + override def forall(p: ((K, V)) => Boolean): Boolean = p((key1, value1)) && p((key2, value2)) && p((key3, value3)) && p((key4, value4)) + override protected[collection] def filterImpl(pred: ((K, V)) => Boolean, isFlipped: Boolean): Map[K, V] = { + var k1, k2, k3 = null.asInstanceOf[K] + var v1, v2, v3 = null.asInstanceOf[V] + var n = 0 + if (pred((key1, value1)) != isFlipped) { { k1 = key1; v1 = value1 }; n += 1} + if (pred((key2, value2)) != isFlipped) { if (n == 0) { k1 = key2; v1 = value2 } else { k2 = key2; v2 = value2 }; n += 1} + if (pred((key3, value3)) != isFlipped) { if (n == 0) { k1 = key3; v1 = value3 } else if (n == 1) { k2 = key3; v2 = value3 } else { k3 = key3; v3 = value3}; n += 1} + if (pred((key4, value4)) != isFlipped) { if (n == 0) { k1 = key4; v1 = value4 } else if (n == 1) { k2 = key4; v2 = value4 } else if (n == 2) { k3 = key4; v3 = value4 }; n += 1} + + n match { + case 0 => Map.empty + case 1 => new Map1(k1, v1) + case 2 => new Map2(k1, v1, k2, v2) + case 3 => new Map3(k1, v1, k2, v2, k3, v3) + case 4 => this + } + } + override def transform[W](f: (K, V) => W): Map[K, W] = { + val walue1 = f(key1, value1) + val walue2 = f(key2, value2) + val walue3 = f(key3, value3) + val walue4 = f(key4, value4) + if ((walue1.asInstanceOf[AnyRef] eq value1.asInstanceOf[AnyRef]) && + (walue2.asInstanceOf[AnyRef] eq value2.asInstanceOf[AnyRef]) && + (walue3.asInstanceOf[AnyRef] eq value3.asInstanceOf[AnyRef]) && + (walue4.asInstanceOf[AnyRef] eq value4.asInstanceOf[AnyRef])) this.asInstanceOf[Map[K, W]] + else new Map4(key1, walue1, key2, walue2, key3, walue3, key4, walue4) + } + private[immutable] def buildTo[V1 >: V](builder: HashMapBuilder[K, V1]): builder.type = + builder.addOne(key1, value1).addOne(key2, value2).addOne(key3, value3).addOne(key4, value4) + override def hashCode(): Int = { + import scala.util.hashing.MurmurHash3 + var a, b = 0 + val N = 4 + var c = 1 + + var h = MurmurHash3.tuple2Hash(key1, value1) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.tuple2Hash(key2, value2) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.tuple2Hash(key3, value3) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.tuple2Hash(key4, value4) + a += h + b ^= h + c *= h | 1 + + h = MurmurHash3.mapSeed + h = MurmurHash3.mix(h, a) + h = MurmurHash3.mix(h, b) + h = MurmurHash3.mixLast(h, c) + MurmurHash3.finalizeHash(h, N) + } + } +} + +/** Explicit instantiation of the `Map` trait to reduce class file size in subclasses. */ +abstract class AbstractMap[K, +V] extends scala.collection.AbstractMap[K, V] with Map[K, V] + +private[immutable] final class MapBuilderImpl[K, V] extends ReusableBuilder[(K, V), Map[K, V]] { + private[this] var elems: Map[K, V] @uncheckedCaptures = Map.empty + private[this] var switchedToHashMapBuilder: Boolean = false + private[this] var hashMapBuilder: HashMapBuilder[K, V] @uncheckedCaptures = _ + + private[immutable] def getOrElse[V0 >: V](key: K, value: V0): V0 = + if (hashMapBuilder ne null) hashMapBuilder.getOrElse(key, value) + else elems.getOrElse(key, value) + + override def clear(): Unit = { + elems = Map.empty + if (hashMapBuilder != null) { + hashMapBuilder.clear() + } + switchedToHashMapBuilder = false + } + + override def result(): Map[K, V] = + if (switchedToHashMapBuilder) hashMapBuilder.result() else elems + + def addOne(key: K, value: V): this.type = { + if (switchedToHashMapBuilder) { + hashMapBuilder.addOne(key, value) + } else if (elems.size < 4) { + elems = elems.updated(key, value) + } else { + // assert(elems.size == 4) + if (elems.contains(key)) { + elems = elems.updated(key, value) + } else { + switchedToHashMapBuilder = true + if (hashMapBuilder == null) { + hashMapBuilder = new HashMapBuilder + } + elems.asInstanceOf[Map4[K, V]].buildTo(hashMapBuilder) + hashMapBuilder.addOne(key, value) + } + } + + this + } + + def addOne(elem: (K, V)) = addOne(elem._1, elem._2) + + override def addAll(xs: IterableOnce[(K, V)]^): this.type = + if (switchedToHashMapBuilder) { + hashMapBuilder.addAll(xs) + this + } else { + super.addAll(xs) + } +} From a1fc706f533bad88a5384170f872aad05944fb1a Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 10:59:59 +0100 Subject: [PATCH 68/89] Add Range classes to stdlib --- .../collection/immutable/NumericRange.scala | 509 +++++++++++++ .../stdlib/collection/immutable/Range.scala | 673 ++++++++++++++++++ 2 files changed, 1182 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/NumericRange.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/Range.scala diff --git a/tests/pos-special/stdlib/collection/immutable/NumericRange.scala b/tests/pos-special/stdlib/collection/immutable/NumericRange.scala new file mode 100644 index 000000000000..f26d9728e5ad --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/NumericRange.scala @@ -0,0 +1,509 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.immutable + +import scala.collection.Stepper.EfficientSplit +import scala.collection.{AbstractIterator, AnyStepper, IterableFactoryDefaults, Iterator, Stepper, StepperShape} +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** `NumericRange` is a more generic version of the + * `Range` class which works with arbitrary types. + * It must be supplied with an `Integral` implementation of the + * range type. + * + * Factories for likely types include `Range.BigInt`, `Range.Long`, + * and `Range.BigDecimal`. `Range.Int` exists for completeness, but + * the `Int`-based `scala.Range` should be more performant. + * + * {{{ + * val r1 = Range(0, 100, 1) + * val veryBig = Int.MaxValue.toLong + 1 + * val r2 = Range.Long(veryBig, veryBig + 100, 1) + * assert(r1 sameElements r2.map(_ - veryBig)) + * }}} + * + * @define Coll `NumericRange` + * @define coll numeric range + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +@SerialVersionUID(3L) +sealed class NumericRange[T]( + val start: T, + val end: T, + val step: T, + val isInclusive: Boolean +)(implicit + num: Integral[T] +) + extends AbstractSeq[T] + with IndexedSeq[T] + with IndexedSeqOps[T, IndexedSeq, IndexedSeq[T]] + with StrictOptimizedSeqOps[T, IndexedSeq, IndexedSeq[T]] + with IterableFactoryDefaults[T, IndexedSeq] + with Serializable { self => + + override def iterator: Iterator[T] = new NumericRange.NumericRangeIterator(this, num) + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[T, S]): S with EfficientSplit = { + import scala.collection.convert._ + import impl._ + val s = shape.shape match { + case StepperShape.IntShape => new IntNumericRangeStepper (this.asInstanceOf[NumericRange[Int]], 0, length) + case StepperShape.LongShape => new LongNumericRangeStepper (this.asInstanceOf[NumericRange[Long]], 0, length) + case _ => shape.parUnbox(new AnyNumericRangeStepper[T](this, 0, length).asInstanceOf[AnyStepper[T] with EfficientSplit]) + } + s.asInstanceOf[S with EfficientSplit] + } + + + /** Note that NumericRange must be invariant so that constructs + * such as "1L to 10 by 5" do not infer the range type as AnyVal. + */ + import num._ + + // See comment in Range for why this must be lazy. + override lazy val length: Int = NumericRange.count(start, end, step, isInclusive) + override lazy val isEmpty: Boolean = ( + (num.gt(start, end) && num.gt(step, num.zero)) + || (num.lt(start, end) && num.lt(step, num.zero)) + || (num.equiv(start, end) && !isInclusive) + ) + override def last: T = + if (isEmpty) Nil.head + else locationAfterN(length - 1) + override def init: NumericRange[T] = + if (isEmpty) Nil.init + else new NumericRange(start, end - step, step, isInclusive) + + override def head: T = if (isEmpty) Nil.head else start + override def tail: NumericRange[T] = + if (isEmpty) Nil.tail + else if(isInclusive) new NumericRange.Inclusive(start + step, end, step) + else new NumericRange.Exclusive(start + step, end, step) + + /** Create a new range with the start and end values of this range and + * a new `step`. + */ + def by(newStep: T): NumericRange[T] = copy(start, end, newStep) + + + /** Create a copy of this range. + */ + def copy(start: T, end: T, step: T): NumericRange[T] = + new NumericRange(start, end, step, isInclusive) + + @throws[IndexOutOfBoundsException] + def apply(idx: Int): T = { + if (idx < 0 || idx >= length) throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${length - 1})") + else locationAfterN(idx) + } + + override def foreach[@specialized(Specializable.Unit) U](f: T => U): Unit = { + var count = 0 + var current = start + while (count < length) { + f(current) + current += step + count += 1 + } + } + + // TODO: these private methods are straight copies from Range, duplicated + // to guard against any (most likely illusory) performance drop. They should + // be eliminated one way or another. + + // Tests whether a number is within the endpoints, without testing + // whether it is a member of the sequence (i.e. when step > 1.) + private def isWithinBoundaries(elem: T) = !isEmpty && ( + (step > zero && start <= elem && elem <= last ) || + (step < zero && last <= elem && elem <= start) + ) + // Methods like apply throw exceptions on invalid n, but methods like take/drop + // are forgiving: therefore the checks are with the methods. + private def locationAfterN(n: Int): T = start + (step * fromInt(n)) + + private def crossesTheEndAfterN(n: Int): Boolean = { + // if we're sure that subtraction in the context of T won't overflow, we use this function + // to calculate the length of the range + def unsafeRangeLength(r: NumericRange[T]): T = { + val diff = num.minus(r.end, r.start) + val quotient = num.quot(diff, r.step) + val remainder = num.rem(diff, r.step) + if (!r.isInclusive && num.equiv(remainder, num.zero)) + num.max(quotient, num.zero) + else + num.max(num.plus(quotient, num.one), num.zero) + } + + // detects whether value can survive a bidirectional trip to -and then from- Int. + def fitsInInteger(value: T): Boolean = num.equiv(num.fromInt(num.toInt(value)), value) + + val stepIsInTheSameDirectionAsStartToEndVector = + (num.gt(end, start) && num.gt(step, num.zero)) || (num.lt(end, start) && num.sign(step) == -num.one) + + if (num.equiv(start, end) || n <= 0 || !stepIsInTheSameDirectionAsStartToEndVector) return n >= 1 + + val sameSign = num.equiv(num.sign(start), num.sign(end)) + + if (sameSign) { // subtraction is safe + val len = unsafeRangeLength(this) + if (fitsInInteger(len)) n >= num.toInt(len) else num.gteq(num.fromInt(n), len) + } else { + // split to two ranges, which subtraction is safe in both of them (around zero) + val stepsRemainderToZero = num.rem(start, step) + val walksOnZero = num.equiv(stepsRemainderToZero, num.zero) + val closestToZero = if (walksOnZero) -step else stepsRemainderToZero + + /* + When splitting into two ranges, we should be super-careful about one of the sides hitting MinValue of T, + so we take two steps smaller than zero to ensure unsafeRangeLength won't overflow (taking one step may overflow depending on the step). + Same thing happens for MaxValue from zero, so we take one step further to ensure the safety of unsafeRangeLength. + After performing such operation, there are some elements remaining in between and around zero, + which their length is represented by carry. + */ + val (l: NumericRange[T], r: NumericRange[T], carry: Int) = + if (num.lt(start, num.zero)) { + if (walksOnZero) { + val twoStepsAfterLargestNegativeNumber = num.plus(closestToZero, num.times(step, num.fromInt(2))) + (NumericRange(start, closestToZero, step), copy(twoStepsAfterLargestNegativeNumber, end, step), 2) + } else { + (NumericRange(start, closestToZero, step), copy(num.plus(closestToZero, step), end, step), 1) + } + } else { + if (walksOnZero) { + val twoStepsAfterZero = num.times(step, num.fromInt(2)) + (copy(twoStepsAfterZero, end, step), NumericRange.inclusive(start, -step, step), 2) + } else { + val twoStepsAfterSmallestPositiveNumber = num.plus(closestToZero, num.times(step, num.fromInt(2))) + (copy(twoStepsAfterSmallestPositiveNumber, end, step), NumericRange.inclusive(start, closestToZero, step), 2) + } + } + + val leftLength = unsafeRangeLength(l) + val rightLength = unsafeRangeLength(r) + + // instead of `n >= rightLength + leftLength + curry` which may cause addition overflow, + // this can be used `(n - leftLength - curry) >= rightLength` (Both in Int and T, depends on whether the lengths fit in Int) + if (fitsInInteger(leftLength) && fitsInInteger(rightLength)) + n - num.toInt(leftLength) - carry >= num.toInt(rightLength) + else + num.gteq(num.minus(num.minus(num.fromInt(n), leftLength), num.fromInt(carry)), rightLength) + } + } + + // When one drops everything. Can't ever have unchecked operations + // like "end + 1" or "end - 1" because ranges involving Int.{ MinValue, MaxValue } + // will overflow. This creates an exclusive range where start == end + // based on the given value. + private def newEmptyRange(value: T) = NumericRange(value, value, step) + + override def take(n: Int): NumericRange[T] = { + if (n <= 0 || isEmpty) newEmptyRange(start) + else if (crossesTheEndAfterN(n)) this + else new NumericRange.Inclusive(start, locationAfterN(n - 1), step) + } + + override def drop(n: Int): NumericRange[T] = { + if (n <= 0 || isEmpty) this + else if (crossesTheEndAfterN(n)) newEmptyRange(end) + else copy(locationAfterN(n), end, step) + } + + override def splitAt(n: Int): (NumericRange[T], NumericRange[T]) = (take(n), drop(n)) + + override def reverse: NumericRange[T] = + if (isEmpty) this + else { + val newStep = -step + if (num.sign(newStep) == num.sign(step)) { + throw new ArithmeticException("number type is unsigned, and .reverse requires a negative step") + } else new NumericRange.Inclusive(last, start, newStep) + } + + import NumericRange.defaultOrdering + + override def min[T1 >: T](implicit ord: Ordering[T1]): T = + // We can take the fast path: + // - If the Integral of this NumericRange is also the requested Ordering + // (Integral <: Ordering). This can happen for custom Integral types. + // - The Ordering is the default Ordering of a well-known Integral type. + if ((ord eq num) || defaultOrdering.get(num).exists(ord eq _)) { + if (num.sign(step) > zero) head + else last + } else super.min(ord) + + override def max[T1 >: T](implicit ord: Ordering[T1]): T = + // See comment for fast path in min(). + if ((ord eq num) || defaultOrdering.get(num).exists(ord eq _)) { + if (num.sign(step) > zero) last + else head + } else super.max(ord) + + // a well-typed contains method. + def containsTyped(x: T): Boolean = + isWithinBoundaries(x) && (((x - start) % step) == zero) + + override def contains[A1 >: T](x: A1): Boolean = + try containsTyped(x.asInstanceOf[T]) + catch { case _: ClassCastException => false } + + override def sum[B >: T](implicit num: Numeric[B]): B = { + if (isEmpty) num.zero + else if (size == 1) head + else { + // If there is no overflow, use arithmetic series formula + // a + ... (n terms total) ... + b = n*(a+b)/2 + if ((num eq scala.math.Numeric.IntIsIntegral)|| + (num eq scala.math.Numeric.ShortIsIntegral)|| + (num eq scala.math.Numeric.ByteIsIntegral)|| + (num eq scala.math.Numeric.CharIsIntegral)) { + // We can do math with no overflow in a Long--easy + val exact = (size * ((num toLong head) + (num toInt last))) / 2 + num fromInt exact.toInt + } + else if (num eq scala.math.Numeric.LongIsIntegral) { + // Uh-oh, might be overflow, so we have to divide before we overflow. + // Either numRangeElements or (head + last) must be even, so divide the even one before multiplying + val a = head.toLong + val b = last.toLong + val ans = + if ((size & 1) == 0) (size / 2) * (a + b) + else size * { + // Sum is even, but we might overflow it, so divide in pieces and add back remainder + val ha = a/2 + val hb = b/2 + ha + hb + ((a - 2*ha) + (b - 2*hb)) / 2 + } + ans.asInstanceOf[B] + } + else if ((num eq scala.math.Numeric.BigIntIsIntegral) || + (num eq scala.math.Numeric.BigDecimalAsIfIntegral)) { + // No overflow, so we can use arithmetic series formula directly + // (not going to worry about running out of memory) + val numAsIntegral = num.asInstanceOf[Integral[B]] + import numAsIntegral._ + ((num fromInt size) * (head + last)) / (num fromInt 2) + } + else { + // User provided custom Numeric, so we cannot rely on arithmetic series formula (e.g. won't work on something like Z_6) + if (isEmpty) num.zero + else { + var acc = num.zero + var i = head + var idx = 0 + while(idx < length) { + acc = num.plus(acc, i) + i = i + step + idx = idx + 1 + } + acc + } + } + } + } + + override lazy val hashCode: Int = super.hashCode() + override protected final def applyPreferredMaxLength: Int = Int.MaxValue + + override def equals(other: Any): Boolean = other match { + case x: NumericRange[_] => + (x canEqual this) && (length == x.length) && ( + (isEmpty) || // all empty sequences are equal + (start == x.start && last == x.last) // same length and same endpoints implies equality + ) + case _ => + super.equals(other) + } + + override def toString: String = { + val empty = if (isEmpty) "empty " else "" + val preposition = if (isInclusive) "to" else "until" + val stepped = if (step == 1) "" else s" by $step" + s"${empty}NumericRange $start $preposition $end$stepped" + } + + override protected[this] def className = "NumericRange" +} + +/** A companion object for numeric ranges. + * @define Coll `NumericRange` + * @define coll numeric range + */ +object NumericRange { + private def bigDecimalCheckUnderflow[T](start: T, end: T, step: T)(implicit num: Integral[T]): Unit = { + def FAIL(boundary: T, step: T): Unit = { + val msg = boundary match { + case bd: BigDecimal => s"Precision ${bd.mc.getPrecision}" + case _ => "Precision" + } + throw new IllegalArgumentException( + s"$msg inadequate to represent steps of size $step near $boundary" + ) + } + if (num.minus(num.plus(start, step), start) != step) FAIL(start, step) + if (num.minus(end, num.minus(end, step)) != step) FAIL(end, step) + } + + /** Calculates the number of elements in a range given start, end, step, and + * whether or not it is inclusive. Throws an exception if step == 0 or + * the number of elements exceeds the maximum Int. + */ + def count[T](start: T, end: T, step: T, isInclusive: Boolean)(implicit num: Integral[T]): Int = { + val zero = num.zero + val upward = num.lt(start, end) + val posStep = num.gt(step, zero) + + if (step == zero) throw new IllegalArgumentException("step cannot be 0.") + else if (start == end) if (isInclusive) 1 else 0 + else if (upward != posStep) 0 + else { + /* We have to be frightfully paranoid about running out of range. + * We also can't assume that the numbers will fit in a Long. + * We will assume that if a > 0, -a can be represented, and if + * a < 0, -a+1 can be represented. We also assume that if we + * can't fit in Int, we can represent 2*Int.MaxValue+3 (at least). + * And we assume that numbers wrap rather than cap when they overflow. + */ + // Check whether we can short-circuit by deferring to Int range. + val startint = num.toInt(start) + if (start == num.fromInt(startint)) { + val endint = num.toInt(end) + if (end == num.fromInt(endint)) { + val stepint = num.toInt(step) + if (step == num.fromInt(stepint)) { + return { + if (isInclusive) Range.inclusive(startint, endint, stepint).length + else Range (startint, endint, stepint).length + } + } + } + } + // If we reach this point, deferring to Int failed. + // Numbers may be big. + if (num.isInstanceOf[Numeric.BigDecimalAsIfIntegral]) { + bigDecimalCheckUnderflow(start, end, step) // Throw exception if math is inaccurate (including no progress at all) + } + val one = num.one + val limit = num.fromInt(Int.MaxValue) + def check(t: T): T = + if (num.gt(t, limit)) throw new IllegalArgumentException("More than Int.MaxValue elements.") + else t + // If the range crosses zero, it might overflow when subtracted + val startside = num.sign(start) + val endside = num.sign(end) + num.toInt{ + if (num.gteq(num.times(startside, endside), zero)) { + // We're sure we can subtract these numbers. + // Note that we do not use .rem because of different conventions for Long and BigInt + val diff = num.minus(end, start) + val quotient = check(num.quot(diff, step)) + val remainder = num.minus(diff, num.times(quotient, step)) + if (!isInclusive && zero == remainder) quotient else check(num.plus(quotient, one)) + } + else { + // We might not even be able to subtract these numbers. + // Jump in three pieces: + // * start to -1 or 1, whichever is closer (waypointA) + // * one step, which will take us at least to 0 (ends at waypointB) + // * (except with really small numbers) + // * there to the end + val negone = num.fromInt(-1) + val startlim = if (posStep) negone else one + //Use start value if the start value is closer to zero than startlim + // * e.g. .5 is closer to zero than 1 and -.5 is closer to zero than -1 + val startdiff = { + if ((posStep && num.lt(startlim, start)) || (!posStep && num.gt(startlim, start))) + start + else + num.minus(startlim, start) + } + val startq = check(num.quot(startdiff, step)) + val waypointA = if (startq == zero) start else num.plus(start, num.times(startq, step)) + val waypointB = num.plus(waypointA, step) + check { + if (num.lt(waypointB, end) != upward) { + // No last piece + if (isInclusive && waypointB == end) num.plus(startq, num.fromInt(2)) + else num.plus(startq, one) + } + else { + // There is a last piece + val enddiff = num.minus(end,waypointB) + val endq = check(num.quot(enddiff, step)) + val last = if (endq == zero) waypointB else num.plus(waypointB, num.times(endq, step)) + // Now we have to tally up all the pieces + // 1 for the initial value + // startq steps to waypointA + // 1 step to waypointB + // endq steps to the end (one less if !isInclusive and last==end) + num.plus(startq, num.plus(endq, if (!isInclusive && last==end) one else num.fromInt(2))) + } + } + } + } + } + } + + @SerialVersionUID(3L) + class Inclusive[T](start: T, end: T, step: T)(implicit num: Integral[T]) + extends NumericRange(start, end, step, true) { + override def copy(start: T, end: T, step: T): Inclusive[T] = + NumericRange.inclusive(start, end, step) + + def exclusive: Exclusive[T] = NumericRange(start, end, step) + } + + @SerialVersionUID(3L) + class Exclusive[T](start: T, end: T, step: T)(implicit num: Integral[T]) + extends NumericRange(start, end, step, false) { + override def copy(start: T, end: T, step: T): Exclusive[T] = + NumericRange(start, end, step) + + def inclusive: Inclusive[T] = NumericRange.inclusive(start, end, step) + } + + def apply[T](start: T, end: T, step: T)(implicit num: Integral[T]): Exclusive[T] = + new Exclusive(start, end, step) + def inclusive[T](start: T, end: T, step: T)(implicit num: Integral[T]): Inclusive[T] = + new Inclusive(start, end, step) + + private[collection] val defaultOrdering = Map[Numeric[_], Ordering[_]]( + Numeric.BigIntIsIntegral -> Ordering.BigInt, + Numeric.IntIsIntegral -> Ordering.Int, + Numeric.ShortIsIntegral -> Ordering.Short, + Numeric.ByteIsIntegral -> Ordering.Byte, + Numeric.CharIsIntegral -> Ordering.Char, + Numeric.LongIsIntegral -> Ordering.Long, + Numeric.BigDecimalAsIfIntegral -> Ordering.BigDecimal + ) + + @SerialVersionUID(3L) + private final class NumericRangeIterator[T](self: NumericRange[T], num: Integral[T]) extends AbstractIterator[T] with Serializable { + import num.mkNumericOps + + private[this] var _hasNext = !self.isEmpty + private[this] var _next: T @uncheckedCaptures = self.start + private[this] val lastElement: T = if (_hasNext) self.last else self.start + override def knownSize: Int = if (_hasNext) num.toInt((lastElement - _next) / self.step) + 1 else 0 + def hasNext: Boolean = _hasNext + def next(): T = { + if (!_hasNext) Iterator.empty.next() + val value = _next + _hasNext = value != lastElement + _next = num.plus(value, self.step) + value + } + } +} diff --git a/tests/pos-special/stdlib/collection/immutable/Range.scala b/tests/pos-special/stdlib/collection/immutable/Range.scala new file mode 100644 index 000000000000..459591d1a9cb --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/Range.scala @@ -0,0 +1,673 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection.immutable + +import scala.collection.Stepper.EfficientSplit +import scala.collection.convert.impl.RangeStepper +import scala.collection.{AbstractIterator, AnyStepper, IterableFactoryDefaults, Iterator, Stepper, StepperShape} +import scala.util.hashing.MurmurHash3 +import language.experimental.captureChecking + +/** The `Range` class represents integer values in range + * ''[start;end)'' with non-zero step value `step`. + * It's a special case of an indexed sequence. + * For example: + * + * {{{ + * val r1 = 0 until 10 + * val r2 = r1.start until r1.end by r1.step + 1 + * println(r2.length) // = 5 + * }}} + * + * Ranges that contain more than `Int.MaxValue` elements can be created, but + * these overfull ranges have only limited capabilities. Any method that + * could require a collection of over `Int.MaxValue` length to be created, or + * could be asked to index beyond `Int.MaxValue` elements will throw an + * exception. Overfull ranges can safely be reduced in size by changing + * the step size (e.g. `by 3`) or taking/dropping elements. `contains`, + * `equals`, and access to the ends of the range (`head`, `last`, `tail`, + * `init`) are also permitted on overfull ranges. + * + * @param start the start of this range. + * @param end the end of the range. For exclusive ranges, e.g. + * `Range(0,3)` or `(0 until 3)`, this is one + * step past the last one in the range. For inclusive + * ranges, e.g. `Range.inclusive(0,3)` or `(0 to 3)`, + * it may be in the range if it is not skipped by the step size. + * To find the last element inside a non-empty range, + * use `last` instead. + * @param step the step for the range. + * + * @define coll range + * @define mayNotTerminateInf + * @define willNotTerminateInf + * @define doesNotUseBuilders + * '''Note:''' this method does not use builders to construct a new range, + * and its complexity is O(1). + */ +@SerialVersionUID(3L) +sealed abstract class Range( + val start: Int, + val end: Int, + val step: Int +) + extends AbstractSeq[Int] + with IndexedSeq[Int] + with IndexedSeqOps[Int, IndexedSeq, IndexedSeq[Int]] + with StrictOptimizedSeqOps[Int, IndexedSeq, IndexedSeq[Int]] + with IterableFactoryDefaults[Int, IndexedSeq] + with Serializable { range => + + final override def iterator: Iterator[Int] = new RangeIterator(start, step, lastElement, isEmpty) + + override final def stepper[S <: Stepper[_]](implicit shape: StepperShape[Int, S]): S with EfficientSplit = { + val st = new RangeStepper(start, step, 0, length) + val r = + if (shape.shape == StepperShape.IntShape) st + else { + assert(shape.shape == StepperShape.ReferenceShape, s"unexpected StepperShape: $shape") + AnyStepper.ofParIntStepper(st) + } + r.asInstanceOf[S with EfficientSplit] + } + + private[this] def gap = end.toLong - start.toLong + private[this] def isExact = gap % step == 0 + private[this] def hasStub = isInclusive || !isExact + private[this] def longLength = gap / step + ( if (hasStub) 1 else 0 ) + + def isInclusive: Boolean + + final override val isEmpty: Boolean = ( + (start > end && step > 0) + || (start < end && step < 0) + || (start == end && !isInclusive) + ) + + private[this] val numRangeElements: Int = { + if (step == 0) throw new IllegalArgumentException("step cannot be 0.") + else if (isEmpty) 0 + else { + val len = longLength + if (len > scala.Int.MaxValue) -1 + else len.toInt + } + } + + final def length = if (numRangeElements < 0) fail() else numRangeElements + + // This field has a sensible value only for non-empty ranges + private[this] val lastElement = step match { + case 1 => if (isInclusive) end else end-1 + case -1 => if (isInclusive) end else end+1 + case _ => + val remainder = (gap % step).toInt + if (remainder != 0) end - remainder + else if (isInclusive) end + else end - step + } + + /** The last element of this range. This method will return the correct value + * even if there are too many elements to iterate over. + */ + final override def last: Int = + if (isEmpty) throw Range.emptyRangeError("last") else lastElement + final override def head: Int = + if (isEmpty) throw Range.emptyRangeError("head") else start + + /** Creates a new range containing all the elements of this range except the last one. + * + * $doesNotUseBuilders + * + * @return a new range consisting of all the elements of this range except the last one. + */ + final override def init: Range = + if (isEmpty) throw Range.emptyRangeError("init") else dropRight(1) + + /** Creates a new range containing all the elements of this range except the first one. + * + * $doesNotUseBuilders + * + * @return a new range consisting of all the elements of this range except the first one. + */ + final override def tail: Range = { + if (isEmpty) throw Range.emptyRangeError("tail") + if (numRangeElements == 1) newEmptyRange(end) + else if(isInclusive) new Range.Inclusive(start + step, end, step) + else new Range.Exclusive(start + step, end, step) + } + + override def map[B](f: Int => B): IndexedSeq[B] = { + validateMaxLength() + super.map(f) + } + + final protected def copy(start: Int = start, end: Int = end, step: Int = step, isInclusive: Boolean = isInclusive): Range = + if(isInclusive) new Range.Inclusive(start, end, step) else new Range.Exclusive(start, end, step) + + /** Create a new range with the `start` and `end` values of this range and + * a new `step`. + * + * @return a new range with a different step + */ + final def by(step: Int): Range = copy(start, end, step) + + // Check cannot be evaluated eagerly because we have a pattern where + // ranges are constructed like: "x to y by z" The "x to y" piece + // should not trigger an exception. So the calculation is delayed, + // which means it will not fail fast for those cases where failing was + // correct. + private[this] def validateMaxLength(): Unit = { + if (numRangeElements < 0) + fail() + } + private[this] def description = "%d %s %d by %s".format(start, if (isInclusive) "to" else "until", end, step) + private[this] def fail() = throw new IllegalArgumentException(description + ": seqs cannot contain more than Int.MaxValue elements.") + + @throws[IndexOutOfBoundsException] + final def apply(idx: Int): Int = { + validateMaxLength() + if (idx < 0 || idx >= numRangeElements) throw new IndexOutOfBoundsException(s"$idx is out of bounds (min 0, max ${numRangeElements-1})") + else start + (step * idx) + } + + /*@`inline`*/ final override def foreach[@specialized(Unit) U](f: Int => U): Unit = { + // Implementation chosen on the basis of favorable microbenchmarks + // Note--initialization catches step == 0 so we don't need to here + if (!isEmpty) { + var i = start + while (true) { + f(i) + if (i == lastElement) return + i += step + } + } + } + + override final def indexOf[@specialized(Int) B >: Int](elem: B, from: Int = 0): Int = + elem match { + case i: Int => + val pos = posOf(i) + if (pos >= from) pos else -1 + case _ => super.indexOf(elem, from) + } + + override final def lastIndexOf[@specialized(Int) B >: Int](elem: B, end: Int = length - 1): Int = + elem match { + case i: Int => + val pos = posOf(i) + if (pos <= end) pos else -1 + case _ => super.lastIndexOf(elem, end) + } + + private[this] def posOf(i: Int): Int = + if (contains(i)) (i - start) / step else -1 + + override def sameElements[B >: Int](that: IterableOnce[B]^): Boolean = that match { + case other: Range => + (this.length : @annotation.switch) match { + case 0 => other.isEmpty + case 1 => other.length == 1 && this.start == other.start + case n => other.length == n && ( + (this.start == other.start) + && (this.step == other.step) + ) + } + case _ => super.sameElements(that) + } + + /** Creates a new range containing the first `n` elements of this range. + * + * @param n the number of elements to take. + * @return a new range consisting of `n` first elements. + */ + final override def take(n: Int): Range = + if (n <= 0 || isEmpty) newEmptyRange(start) + else if (n >= numRangeElements && numRangeElements >= 0) this + else { + // May have more than Int.MaxValue elements in range (numRangeElements < 0) + // but the logic is the same either way: take the first n + new Range.Inclusive(start, locationAfterN(n - 1), step) + } + + /** Creates a new range containing all the elements of this range except the first `n` elements. + * + * @param n the number of elements to drop. + * @return a new range consisting of all the elements of this range except `n` first elements. + */ + final override def drop(n: Int): Range = + if (n <= 0 || isEmpty) this + else if (n >= numRangeElements && numRangeElements >= 0) newEmptyRange(end) + else { + // May have more than Int.MaxValue elements (numRangeElements < 0) + // but the logic is the same either way: go forwards n steps, keep the rest + copy(locationAfterN(n), end, step) + } + + /** Creates a new range consisting of the last `n` elements of the range. + * + * $doesNotUseBuilders + */ + final override def takeRight(n: Int): Range = { + if (n <= 0) newEmptyRange(start) + else if (numRangeElements >= 0) drop(numRangeElements - n) + else { + // Need to handle over-full range separately + val y = last + val x = y - step.toLong*(n-1) + if ((step > 0 && x < start) || (step < 0 && x > start)) this + else Range.inclusive(x.toInt, y, step) + } + } + + /** Creates a new range consisting of the initial `length - n` elements of the range. + * + * $doesNotUseBuilders + */ + final override def dropRight(n: Int): Range = { + if (n <= 0) this + else if (numRangeElements >= 0) take(numRangeElements - n) + else { + // Need to handle over-full range separately + val y = last - step.toInt*n + if ((step > 0 && y < start) || (step < 0 && y > start)) newEmptyRange(start) + else Range.inclusive(start, y.toInt, step) + } + } + + // Advance from the start while we meet the given test + private[this] def argTakeWhile(p: Int => Boolean): Long = { + if (isEmpty) start + else { + var current = start + val stop = last + while (current != stop && p(current)) current += step + if (current != stop || !p(current)) current + else current.toLong + step + } + } + + final override def takeWhile(p: Int => Boolean): Range = { + val stop = argTakeWhile(p) + if (stop==start) newEmptyRange(start) + else { + val x = (stop - step).toInt + if (x == last) this + else Range.inclusive(start, x, step) + } + } + + final override def dropWhile(p: Int => Boolean): Range = { + val stop = argTakeWhile(p) + if (stop == start) this + else { + val x = (stop - step).toInt + if (x == last) newEmptyRange(last) + else Range.inclusive(x + step, last, step) + } + } + + final override def span(p: Int => Boolean): (Range, Range) = { + val border = argTakeWhile(p) + if (border == start) (newEmptyRange(start), this) + else { + val x = (border - step).toInt + if (x == last) (this, newEmptyRange(last)) + else (Range.inclusive(start, x, step), Range.inclusive(x+step, last, step)) + } + } + + /** Creates a new range containing the elements starting at `from` up to but not including `until`. + * + * $doesNotUseBuilders + * + * @param from the element at which to start + * @param until the element at which to end (not included in the range) + * @return a new range consisting of a contiguous interval of values in the old range + */ + final override def slice(from: Int, until: Int): Range = + if (from <= 0) take(until) + else if (until >= numRangeElements && numRangeElements >= 0) drop(from) + else { + val fromValue = locationAfterN(from) + if (from >= until) newEmptyRange(fromValue) + else Range.inclusive(fromValue, locationAfterN(until-1), step) + } + + // Overridden only to refine the return type + final override def splitAt(n: Int): (Range, Range) = (take(n), drop(n)) + + // Methods like apply throw exceptions on invalid n, but methods like take/drop + // are forgiving: therefore the checks are with the methods. + private[this] def locationAfterN(n: Int) = start + (step * n) + + // When one drops everything. Can't ever have unchecked operations + // like "end + 1" or "end - 1" because ranges involving Int.{ MinValue, MaxValue } + // will overflow. This creates an exclusive range where start == end + // based on the given value. + private[this] def newEmptyRange(value: Int) = new Range.Exclusive(value, value, step) + + /** Returns the reverse of this range. + */ + final override def reverse: Range = + if (isEmpty) this + else new Range.Inclusive(last, start, -step) + + /** Make range inclusive. + */ + final def inclusive: Range = + if (isInclusive) this + else new Range.Inclusive(start, end, step) + + final def contains(x: Int): Boolean = { + if (x == end && !isInclusive) false + else if (step > 0) { + if (x < start || x > end) false + else (step == 1) || (Integer.remainderUnsigned(x - start, step) == 0) + } + else { + if (x < end || x > start) false + else (step == -1) || (Integer.remainderUnsigned(start - x, -step) == 0) + } + } + /* Seq#contains has a type parameter so the optimised contains above doesn't override it */ + override final def contains[B >: Int](elem: B): Boolean = elem match { + case i: Int => this.contains(i) + case _ => super.contains(elem) + } + + final override def sum[B >: Int](implicit num: Numeric[B]): Int = { + if (num eq scala.math.Numeric.IntIsIntegral) { + // this is normal integer range with usual addition. arithmetic series formula can be used + if (isEmpty) 0 + else if (size == 1) head + else ((size * (head.toLong + last)) / 2).toInt + } else { + // user provided custom Numeric, we cannot rely on arithmetic series formula + if (isEmpty) num.toInt(num.zero) + else { + var acc = num.zero + var i = head + while (true) { + acc = num.plus(acc, i) + if (i == lastElement) return num.toInt(acc) + i = i + step + } + 0 // Never hit this--just to satisfy compiler since it doesn't know while(true) has type Nothing + } + } + } + + final override def min[A1 >: Int](implicit ord: Ordering[A1]): Int = + if (ord eq Ordering.Int) { + if (step > 0) head + else last + } else if (Ordering.Int isReverseOf ord) { + if (step > 0) last + else head + } else super.min(ord) + + final override def max[A1 >: Int](implicit ord: Ordering[A1]): Int = + if (ord eq Ordering.Int) { + if (step > 0) last + else head + } else if (Ordering.Int isReverseOf ord) { + if (step > 0) head + else last + } else super.max(ord) + + override def tails: Iterator[Range] = + new AbstractIterator[Range] { + private[this] var i = 0 + override def hasNext = i <= Range.this.length + override def next() = { + if (hasNext) { + val res = Range.this.drop(i) + i += 1 + res + } else { + Iterator.empty.next() + } + } + } + + override def inits: Iterator[Range] = + new AbstractIterator[Range] { + private[this] var i = 0 + override def hasNext = i <= Range.this.length + override def next() = { + if (hasNext) { + val res = Range.this.dropRight(i) + i += 1 + res + } else { + Iterator.empty.next() + } + } + } + override protected final def applyPreferredMaxLength: Int = Int.MaxValue + + final override def equals(other: Any): Boolean = other match { + case x: Range => + // Note: this must succeed for overfull ranges (length > Int.MaxValue) + if (isEmpty) x.isEmpty // empty sequences are equal + else // this is non-empty... + x.nonEmpty && start == x.start && { // ...so other must contain something and have same start + val l0 = last + (l0 == x.last && ( // And same end + start == l0 || step == x.step // And either the same step, or not take any steps + )) + } + case _ => + super.equals(other) + } + + final override def hashCode: Int = + if(length >= 2) MurmurHash3.rangeHash(start, step, lastElement) + else super.hashCode + + final override def toString: String = { + val preposition = if (isInclusive) "to" else "until" + val stepped = if (step == 1) "" else s" by $step" + val prefix = if (isEmpty) "empty " else if (!isExact) "inexact " else "" + s"${prefix}Range $start $preposition $end$stepped" + } + + override protected[this] def className = "Range" + + override def distinct: Range = this + + override def grouped(size: Int): Iterator[Range] = { + require(size >= 1, f"size=$size%d, but size must be positive") + if (isEmpty) { + Iterator.empty + } else { + val s = size + new AbstractIterator[Range] { + private[this] var i = 0 + override def hasNext = Range.this.length > i + override def next() = + if (hasNext) { + val x = Range.this.slice(i, i + s) + i += s + x + } else { + Iterator.empty.next() + } + } + } + } + + override def sorted[B >: Int](implicit ord: Ordering[B]): IndexedSeq[Int] = + if (ord eq Ordering.Int) { + if (step > 0) { + this + } else { + reverse + } + } else { + super.sorted(ord) + } +} + +/** + * Companion object for ranges. + * @define Coll `Range` + * @define coll range + */ +object Range { + + /** Counts the number of range elements. + * precondition: step != 0 + * If the size of the range exceeds Int.MaxValue, the + * result will be negative. + */ + def count(start: Int, end: Int, step: Int, isInclusive: Boolean): Int = { + if (step == 0) + throw new IllegalArgumentException("step cannot be 0.") + + val isEmpty = + if (start == end) !isInclusive + else if (start < end) step < 0 + else step > 0 + + if (isEmpty) 0 + else { + // Counts with Longs so we can recognize too-large ranges. + val gap: Long = end.toLong - start.toLong + val jumps: Long = gap / step + // Whether the size of this range is one larger than the + // number of full-sized jumps. + val hasStub = isInclusive || (gap % step != 0) + val result: Long = jumps + ( if (hasStub) 1 else 0 ) + + if (result > scala.Int.MaxValue) -1 + else result.toInt + } + } + def count(start: Int, end: Int, step: Int): Int = + count(start, end, step, isInclusive = false) + + /** Make a range from `start` until `end` (exclusive) with given step value. + * @note step != 0 + */ + def apply(start: Int, end: Int, step: Int): Range.Exclusive = new Range.Exclusive(start, end, step) + + /** Make a range from `start` until `end` (exclusive) with step value 1. + */ + def apply(start: Int, end: Int): Range.Exclusive = new Range.Exclusive(start, end, 1) + + /** Make an inclusive range from `start` to `end` with given step value. + * @note step != 0 + */ + def inclusive(start: Int, end: Int, step: Int): Range.Inclusive = new Range.Inclusive(start, end, step) + + /** Make an inclusive range from `start` to `end` with step value 1. + */ + def inclusive(start: Int, end: Int): Range.Inclusive = new Range.Inclusive(start, end, 1) + + @SerialVersionUID(3L) + final class Inclusive(start: Int, end: Int, step: Int) extends Range(start, end, step) { + def isInclusive: Boolean = true + } + + @SerialVersionUID(3L) + final class Exclusive(start: Int, end: Int, step: Int) extends Range(start, end, step) { + def isInclusive: Boolean = false + } + + // BigInt and Long are straightforward generic ranges. + object BigInt { + def apply(start: BigInt, end: BigInt, step: BigInt): NumericRange.Exclusive[BigInt] = NumericRange(start, end, step) + def inclusive(start: BigInt, end: BigInt, step: BigInt): NumericRange.Inclusive[BigInt] = NumericRange.inclusive(start, end, step) + } + + object Long { + def apply(start: Long, end: Long, step: Long): NumericRange.Exclusive[Long] = NumericRange(start, end, step) + def inclusive(start: Long, end: Long, step: Long): NumericRange.Inclusive[Long] = NumericRange.inclusive(start, end, step) + } + + // BigDecimal uses an alternative implementation of Numeric in which + // it pretends to be Integral[T] instead of Fractional[T]. See Numeric for + // details. The intention is for it to throw an exception anytime + // imprecision or surprises might result from anything, although this may + // not yet be fully implemented. + object BigDecimal { + implicit val bigDecAsIntegral: Numeric.BigDecimalAsIfIntegral = Numeric.BigDecimalAsIfIntegral + + def apply(start: BigDecimal, end: BigDecimal, step: BigDecimal): NumericRange.Exclusive[BigDecimal] = + NumericRange(start, end, step) + def inclusive(start: BigDecimal, end: BigDecimal, step: BigDecimal): NumericRange.Inclusive[BigDecimal] = + NumericRange.inclusive(start, end, step) + } + + // As there is no appealing default step size for not-really-integral ranges, + // we offer a partially constructed object. + class Partial[T, U](private val f: T -> U) extends AnyVal { + def by(x: T): U = f(x) + override def toString = "Range requires step" + } + + // Illustrating genericity with Int Range, which should have the same behavior + // as the original Range class. However we leave the original Range + // indefinitely, for performance and because the compiler seems to bootstrap + // off it and won't do so with our parameterized version without modifications. + object Int { + def apply(start: Int, end: Int, step: Int): NumericRange.Exclusive[Int] = NumericRange(start, end, step) + def inclusive(start: Int, end: Int, step: Int): NumericRange.Inclusive[Int] = NumericRange.inclusive(start, end, step) + } + + private def emptyRangeError(what: String): Throwable = + new NoSuchElementException(what + " on empty Range") +} + +/** + * @param lastElement The last element included in the Range + * @param initiallyEmpty Whether the Range was initially empty or not + */ +@SerialVersionUID(3L) +private class RangeIterator( + start: Int, + step: Int, + lastElement: Int, + initiallyEmpty: Boolean +) extends AbstractIterator[Int] with Serializable { + private[this] var _hasNext: Boolean = !initiallyEmpty + private[this] var _next: Int = start + override def knownSize: Int = if (_hasNext) (lastElement - _next) / step + 1 else 0 + def hasNext: Boolean = _hasNext + @throws[NoSuchElementException] + def next(): Int = { + if (!_hasNext) Iterator.empty.next() + val value = _next + _hasNext = value != lastElement + _next = value + step + value + } + + override def drop(n: Int): Iterator[Int] = { + if (n > 0) { + val longPos = _next.toLong + step * n + if (step > 0) { + _next = Math.min(lastElement, longPos).toInt + _hasNext = longPos <= lastElement + } + else if (step < 0) { + _next = Math.max(lastElement, longPos).toInt + _hasNext = longPos >= lastElement + } + } + this + } +} From 5817d400c12c96c8147b2feb1bd57127803e1809 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 11:03:38 +0100 Subject: [PATCH 69/89] Add immutable Queue to stdlib --- .../stdlib/collection/immutable/Queue.scala | 218 ++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/Queue.scala diff --git a/tests/pos-special/stdlib/collection/immutable/Queue.scala b/tests/pos-special/stdlib/collection/immutable/Queue.scala new file mode 100644 index 000000000000..929c79ce588a --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/Queue.scala @@ -0,0 +1,218 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package immutable + +import scala.collection.generic.DefaultSerializable +import scala.collection.mutable.{Builder, ListBuffer} +import language.experimental.captureChecking + +/** `Queue` objects implement data structures that allow to + * insert and retrieve elements in a first-in-first-out (FIFO) manner. + * + * `Queue` is implemented as a pair of `List`s, one containing the ''in'' elements and the other the ''out'' elements. + * Elements are added to the ''in'' list and removed from the ''out'' list. When the ''out'' list runs dry, the + * queue is pivoted by replacing the ''out'' list by ''in.reverse'', and ''in'' by ''Nil''. + * + * Adding items to the queue always has cost `O(1)`. Removing items has cost `O(1)`, except in the case + * where a pivot is required, in which case, a cost of `O(n)` is incurred, where `n` is the number of elements in the queue. When this happens, + * `n` remove operations with `O(1)` cost are guaranteed. Removing an item is on average `O(1)`. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#immutable-queues "Scala's Collection Library overview"]] + * section on `Immutable Queues` for more information. + * + * @define Coll `immutable.Queue` + * @define coll immutable queue + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ + +sealed class Queue[+A] protected(protected val in: List[A], protected val out: List[A]) + extends AbstractSeq[A] + with LinearSeq[A] + with LinearSeqOps[A, Queue, Queue[A]] + with StrictOptimizedLinearSeqOps[A, Queue, Queue[A]] + with StrictOptimizedSeqOps[A, Queue, Queue[A]] + with IterableFactoryDefaults[A, Queue] + with DefaultSerializable { + + override def iterableFactory: SeqFactory[Queue] = Queue + + /** Returns the `n`-th element of this queue. + * The first element is at position `0`. + * + * @param n index of the element to return + * @return the element at position `n` in this queue. + * @throws NoSuchElementException if the queue is too short. + */ + override def apply(n: Int): A = { + def indexOutOfRange(): Nothing = throw new IndexOutOfBoundsException(n.toString) + + var index = 0 + var curr = out + + while (index < n && curr.nonEmpty) { + index += 1 + curr = curr.tail + } + + if (index == n) { + if (curr.nonEmpty) curr.head + else if (in.nonEmpty) in.last + else indexOutOfRange() + } else { + val indexFromBack = n - index + val inLength = in.length + if (indexFromBack >= inLength) indexOutOfRange() + else in(inLength - indexFromBack - 1) + } + } + + /** Returns the elements in the list as an iterator + */ + override def iterator: Iterator[A] = out.iterator.concat(in.reverse) + + /** Checks if the queue is empty. + * + * @return true, iff there is no element in the queue. + */ + override def isEmpty: Boolean = in.isEmpty && out.isEmpty + + override def head: A = + if (out.nonEmpty) out.head + else if (in.nonEmpty) in.last + else throw new NoSuchElementException("head on empty queue") + + override def tail: Queue[A] = + if (out.nonEmpty) new Queue(in, out.tail) + else if (in.nonEmpty) new Queue(Nil, in.reverse.tail) + else throw new NoSuchElementException("tail on empty queue") + + override def last: A = + if (in.nonEmpty) in.head + else if (out.nonEmpty) out.last + else throw new NoSuchElementException("last on empty queue") + + /* This is made to avoid inefficient implementation of iterator. */ + override def forall(p: A => Boolean): Boolean = + in.forall(p) && out.forall(p) + + /* This is made to avoid inefficient implementation of iterator. */ + override def exists(p: A => Boolean): Boolean = + in.exists(p) || out.exists(p) + + override protected[this] def className = "Queue" + + /** Returns the length of the queue. */ + override def length: Int = in.length + out.length + + override def prepended[B >: A](elem: B): Queue[B] = new Queue(in, elem :: out) + + override def appended[B >: A](elem: B): Queue[B] = enqueue(elem) + + override def appendedAll[B >: A](that: scala.collection.IterableOnce[B]^): Queue[B] = { + val newIn = that match { + case that: Queue[B] => that.in ++ (that.out reverse_::: this.in) + case that: List[B] => that reverse_::: this.in + case _ => + var result: List[B] = this.in + val iter = that.iterator + while (iter.hasNext) { + result = iter.next() :: result + } + result + } + if (newIn eq this.in) this else new Queue[B](newIn, this.out) + } + + /** Creates a new queue with element added at the end + * of the old queue. + * + * @param elem the element to insert + */ + def enqueue[B >: A](elem: B): Queue[B] = new Queue(elem :: in, out) + + /** Creates a new queue with all elements provided by an `Iterable` object + * added at the end of the old queue. + * + * The elements are appended in the order they are given out by the + * iterator. + * + * @param iter an iterable object + */ + @deprecated("Use `enqueueAll` instead of `enqueue` to enqueue a collection of elements", "2.13.0") + @`inline` final def enqueue[B >: A](iter: scala.collection.Iterable[B]) = enqueueAll(iter) + + /** Creates a new queue with all elements provided by an `Iterable` object + * added at the end of the old queue. + * + * The elements are appended in the order they are given out by the + * iterator. + * + * @param iter an iterable object + */ + def enqueueAll[B >: A](iter: scala.collection.Iterable[B]): Queue[B] = appendedAll(iter) + + /** Returns a tuple with the first element in the queue, + * and a new queue with this element removed. + * + * @throws NoSuchElementException + * @return the first element of the queue. + */ + def dequeue: (A, Queue[A]) = out match { + case Nil if !in.isEmpty => val rev = in.reverse ; (rev.head, new Queue(Nil, rev.tail)) + case x :: xs => (x, new Queue(in, xs)) + case _ => throw new NoSuchElementException("dequeue on empty queue") + } + + /** Optionally retrieves the first element and a queue of the remaining elements. + * + * @return A tuple of the first element of the queue, and a new queue with this element removed. + * If the queue is empty, `None` is returned. + */ + def dequeueOption: Option[(A, Queue[A])] = if(isEmpty) None else Some(dequeue) + + /** Returns the first element in the queue, or throws an error if there + * is no element contained in the queue. + * + * @throws NoSuchElementException + * @return the first element. + */ + def front: A = head + + /** Returns a string representation of this queue. + */ + override def toString(): String = mkString("Queue(", ", ", ")") +} + +/** $factoryInfo + * @define Coll `immutable.Queue` + * @define coll immutable queue + */ +@SerialVersionUID(3L) +object Queue extends StrictOptimizedSeqFactory[Queue] { + def newBuilder[sealed A]: Builder[A, Queue[A]] = new ListBuffer[A] mapResult (x => new Queue[A](Nil, x)) + + def from[A](source: IterableOnce[A]^): Queue[A] = source match { + case q: Queue[A] => q + case _ => + val list = List.from(source) + if (list.isEmpty) empty + else new Queue(Nil, list) + } + + def empty[A]: Queue[A] = EmptyQueue + override def apply[A](xs: A*): Queue[A] = new Queue[A](Nil, xs.toList) + + private object EmptyQueue extends Queue[Nothing](Nil, Nil) { } +} From c16afe52321a72b385fa5d434570135560f614a7 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 11:43:09 +0100 Subject: [PATCH 70/89] Add immutable RedBlackTree to stdlib --- .../collection/immutable/RedBlackTree.scala | 1234 +++++++++++++++++ 1 file changed, 1234 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/RedBlackTree.scala diff --git a/tests/pos-special/stdlib/collection/immutable/RedBlackTree.scala b/tests/pos-special/stdlib/collection/immutable/RedBlackTree.scala new file mode 100644 index 000000000000..5fbc927d7a21 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/RedBlackTree.scala @@ -0,0 +1,1234 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.meta.{getter, setter} +import scala.annotation.tailrec +import scala.runtime.Statics.releaseFence +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** An object containing the RedBlack tree implementation used by for `TreeMaps` and `TreeSets`. + * + * Implementation note: since efficiency is important for data structures this implementation + * uses `null` to represent empty trees. This also means pattern matching cannot + * easily be used. The API represented by the RedBlackTree object tries to hide these + * optimizations behind a reasonably clean API. + */ +private[collection] object RedBlackTree { + + def isEmpty(tree: Tree[_, _]): Boolean = tree eq null + + def contains[A: Ordering](tree: Tree[A, _], x: A): Boolean = lookup(tree, x) ne null + def get[A: Ordering, B](tree: Tree[A, B], x: A): Option[B] = lookup(tree, x) match { + case null => None + case tree => Some(tree.value) + } + + @tailrec + def lookup[A, B](tree: Tree[A, B], x: A)(implicit ordering: Ordering[A]): Tree[A, B] = if (tree eq null) null else { + val cmp = ordering.compare(x, tree.key) + if (cmp < 0) lookup(tree.left, x) + else if (cmp > 0) lookup(tree.right, x) + else tree + } + private[immutable] abstract class Helper[A](implicit val ordering: Ordering[A]) { + def beforePublish[B](tree: Tree[A, B]): Tree[A, B] = { + if (tree eq null) tree + else if (tree.isMutable) { + val res = tree.mutableBlack.makeImmutable + releaseFence() + res + } else tree.black + } + /** Create a new balanced tree where `newLeft` replaces `tree.left`. + * tree and newLeft are never null */ + protected[this] final def mutableBalanceLeft[A1, B, B1 >: B](tree: Tree[A1, B], newLeft: Tree[A1, B1]): Tree[A1, B1] = { + // Parameter trees + // tree | newLeft + // -- KV R | nl.L nl.KV nl.R + // | nl.R.L nl.R.KV nl.R.R + //Note - unlike the immutable trees we can't consider tree.left eq newLeft + //as the balance operations may mutate the same object + //but that check was mostly to avoid the object creation + if (newLeft.isRed) { + val newLeft_left = newLeft.left + val newLeft_right = newLeft.right + if (isRedTree(newLeft_left)) { + // RED + // black(nl.L) nl.KV black + // nl.R KV R + val resultLeft = newLeft_left.mutableBlack + val resultRight = tree.mutableBlackWithLeft(newLeft_right) + + newLeft.mutableWithLeftRight(resultLeft, resultRight) + } else if (isRedTree(newLeft_right)) { + // RED + // black nl.R.KV black + // nl.L nl.KV nl.R.L nl.R.R KV R + + val newLeft_right_right = newLeft_right.right + + val resultLeft = newLeft.mutableBlackWithRight(newLeft_right.left) + val resultRight = tree.mutableBlackWithLeft(newLeft_right_right) + + newLeft_right.mutableWithLeftRight(resultLeft, resultRight) + } else { + // tree + // newLeft KV R + tree.mutableWithLeft(newLeft) + } + } else { + // tree + // newLeft KV R + tree.mutableWithLeft(newLeft) + } + } + /** Create a new balanced tree where `newRight` replaces `tree.right`. + * tree and newRight are never null */ + protected[this] final def mutableBalanceRight[A1, B, B1 >: B](tree: Tree[A1, B], newRight: Tree[A1, B1]): Tree[A1, B1] = { + // Parameter trees + // tree | newRight + // L KV -- | nr.L nr.KV nr.R + // | nr.L.L nr.L.KV nr.L.R + //Note - unlike the immutable trees we can't consider tree.right eq newRight + //as the balance operations may mutate the same object + //but that check was mostly to avoid the object creation + if (newRight.isRed) { + val newRight_left = newRight.left + if (isRedTree(newRight_left)) { + // RED + // black nr.L.KV black + // L KV nr.L.L nr.L.R nr.KV nr.R + + val resultLeft = tree.mutableBlackWithRight(newRight_left.left) + val resultRight = newRight.mutableBlackWithLeft(newRight_left.right) + + newRight_left.mutableWithLeftRight(resultLeft, resultRight) + + } else { + val newRight_right = newRight.right + if (isRedTree(newRight_right)) { + // RED + // black nr.KV black(nr.R) + // L KV nr.L + + val resultLeft = tree.mutableBlackWithRight(newRight_left) + val resultRight = newRight_right.mutableBlack + + newRight.mutableWithLeftRight(resultLeft, resultRight) + } else { + // tree + // L KV newRight + tree.mutableWithRight(newRight) + } + } + } else { + // tree + // L KV newRight + tree.mutableWithRight(newRight) + } + } + } + private[immutable] class SetHelper[A](implicit ordering: Ordering[A]) extends Helper[A] { + protected[this] final def mutableUpd(tree: Tree[A, Any], k: A): Tree[A, Any] = + if (tree eq null) { + mutableRedTree(k, (), null, null) + } else if (k.asInstanceOf[AnyRef] eq tree.key.asInstanceOf[AnyRef]) { + tree + } else { + val cmp = ordering.compare(k, tree.key) + if (cmp < 0) + mutableBalanceLeft(tree, mutableUpd(tree.left, k)) + else if (cmp > 0) + mutableBalanceRight(tree, mutableUpd(tree.right, k)) + else tree + } + } + private[immutable] class MapHelper[A, B](implicit ordering: Ordering[A]) extends Helper[A] { + protected[this] final def mutableUpd[B1 >: B](tree: Tree[A, B], k: A, v: B1): Tree[A, B1] = + if (tree eq null) { + mutableRedTree(k, v, null, null) + } else if (k.asInstanceOf[AnyRef] eq tree.key.asInstanceOf[AnyRef]) { + tree.mutableWithV(v) + } else { + val cmp = ordering.compare(k, tree.key) + if (cmp < 0) + mutableBalanceLeft(tree, mutableUpd(tree.left, k, v)) + else if (cmp > 0) + mutableBalanceRight(tree, mutableUpd(tree.right, k, v)) + else tree.mutableWithV(v) + } + } + + def count(tree: Tree[_, _]) = if (tree eq null) 0 else tree.count + def update[A: Ordering, B, B1 >: B](tree: Tree[A, B], k: A, v: B1, overwrite: Boolean): Tree[A, B1] = blacken(upd(tree, k, v, overwrite)) + def delete[A: Ordering, B](tree: Tree[A, B], k: A): Tree[A, B] = blacken(del(tree, k)) + def rangeImpl[A: Ordering, B](tree: Tree[A, B], from: Option[A], until: Option[A]): Tree[A, B] = (from, until) match { + case (Some(from), Some(until)) => this.range(tree, from, until) + case (Some(from), None) => this.from(tree, from) + case (None, Some(until)) => this.until(tree, until) + case (None, None) => tree + } + def range[A: Ordering, B](tree: Tree[A, B], from: A, until: A): Tree[A, B] = blacken(doRange(tree, from, until)) + def from[A: Ordering, B](tree: Tree[A, B], from: A): Tree[A, B] = blacken(doFrom(tree, from)) + def to[A: Ordering, B](tree: Tree[A, B], to: A): Tree[A, B] = blacken(doTo(tree, to)) + def until[A: Ordering, B](tree: Tree[A, B], key: A): Tree[A, B] = blacken(doUntil(tree, key)) + + def drop[A: Ordering, B](tree: Tree[A, B], n: Int): Tree[A, B] = blacken(doDrop(tree, n)) + def take[A: Ordering, B](tree: Tree[A, B], n: Int): Tree[A, B] = blacken(doTake(tree, n)) + def slice[A: Ordering, B](tree: Tree[A, B], from: Int, until: Int): Tree[A, B] = blacken(doSlice(tree, from, until)) + + def smallest[A, B](tree: Tree[A, B]): Tree[A, B] = { + if (tree eq null) throw new NoSuchElementException("empty tree") + var result = tree + while (result.left ne null) result = result.left + result + } + def greatest[A, B](tree: Tree[A, B]): Tree[A, B] = { + if (tree eq null) throw new NoSuchElementException("empty tree") + var result = tree + while (result.right ne null) result = result.right + result + } + + def tail[A, B](tree: Tree[A, B]): Tree[A, B] = { + def _tail(tree: Tree[A, B]): Tree[A, B] = + if (tree eq null) throw new NoSuchElementException("empty tree") + else { + val tl = tree.left + if (tl eq null) tree.right + else if (tl.isBlack) balLeft(tree, _tail(tl), tree.right) + else tree.redWithLeft(_tail(tree.left)) + } + blacken(_tail(tree)) + } + + def init[A, B](tree: Tree[A, B]): Tree[A, B] = { + def _init(tree: Tree[A, B]): Tree[A, B] = + if (tree eq null) throw new NoSuchElementException("empty tree") + else { + val tr = tree.right + if (tr eq null) tree.left + else if (tr.isBlack) balRight(tree, tree.left, _init(tr)) + else tree.redWithRight(_init(tr)) + } + blacken(_init(tree)) + } + + /** + * Returns the smallest node with a key larger than or equal to `x`. Returns `null` if there is no such node. + */ + def minAfter[A, B](tree: Tree[A, B], x: A)(implicit ordering: Ordering[A]): Tree[A, B] = if (tree eq null) null else { + val cmp = ordering.compare(x, tree.key) + if (cmp == 0) tree + else if (cmp < 0) { + val l = minAfter(tree.left, x) + if (l != null) l else tree + } else minAfter(tree.right, x) + } + + /** + * Returns the largest node with a key smaller than `x`. Returns `null` if there is no such node. + */ + def maxBefore[A, B](tree: Tree[A, B], x: A)(implicit ordering: Ordering[A]): Tree[A, B] = if (tree eq null) null else { + val cmp = ordering.compare(x, tree.key) + if (cmp <= 0) maxBefore(tree.left, x) + else { + val r = maxBefore(tree.right, x) + if (r != null) r else tree + } + } + + def foreach[A,B,U](tree:Tree[A,B], f:((A,B)) => U):Unit = if (tree ne null) _foreach(tree,f) + + def keysEqual[A: Ordering, X, Y](a: Tree[A, X], b: Tree[A, Y]): Boolean = { + if (a eq b) true + else if (a eq null) false + else if (b eq null) false + else a.count == b.count && (new EqualsIterator(a)).sameKeys(new EqualsIterator(b)) + } + def valuesEqual[A: Ordering, X, Y](a: Tree[A, X], b: Tree[A, Y]): Boolean = { + if (a eq b) true + else if (a eq null) false + else if (b eq null) false + else a.count == b.count && (new EqualsIterator(a)).sameValues(new EqualsIterator(b)) + } + def entriesEqual[A: Ordering, X, Y](a: Tree[A, X], b: Tree[A, Y]): Boolean = { + if (a eq b) true + else if (a eq null) false + else if (b eq null) false + else a.count == b.count && (new EqualsIterator(a)).sameEntries(new EqualsIterator(b)) + } + + private[this] def _foreach[A, B, U](tree: Tree[A, B], f: ((A, B)) => U): Unit = { + if (tree.left ne null) _foreach(tree.left, f) + f((tree.key, tree.value)) + if (tree.right ne null) _foreach(tree.right, f) + } + + def foreachKey[A, U](tree:Tree[A,_], f: A => U):Unit = if (tree ne null) _foreachKey(tree,f) + + private[this] def _foreachKey[A, U](tree: Tree[A, _], f: A => U): Unit = { + if (tree.left ne null) _foreachKey(tree.left, f) + f((tree.key)) + if (tree.right ne null) _foreachKey(tree.right, f) + } + + def foreachEntry[A, B, U](tree:Tree[A,B], f: (A, B) => U):Unit = if (tree ne null) _foreachEntry(tree,f) + + private[this] def _foreachEntry[A, B, U](tree: Tree[A, B], f: (A, B) => U): Unit = { + if (tree.left ne null) _foreachEntry(tree.left, f) + f(tree.key, tree.value) + if (tree.right ne null) _foreachEntry(tree.right, f) + } + + def iterator[A: Ordering, B](tree: Tree[A, B], start: Option[A] = None): Iterator[(A, B)] = new EntriesIterator(tree, start) + def keysIterator[A: Ordering](tree: Tree[A, _], start: Option[A] = None): Iterator[A] = new KeysIterator(tree, start) + def valuesIterator[A: Ordering, B](tree: Tree[A, B], start: Option[A] = None): Iterator[B] = new ValuesIterator(tree, start) + + @tailrec + def nth[A, B](tree: Tree[A, B], n: Int): Tree[A, B] = { + val count = this.count(tree.left) + if (n < count) nth(tree.left, n) + else if (n > count) nth(tree.right, n - count - 1) + else tree + } + + def isBlack(tree: Tree[_, _]) = (tree eq null) || tree.isBlack + + @`inline` private[this] def isRedTree(tree: Tree[_, _]) = (tree ne null) && tree.isRed + @`inline` private[this] def isBlackTree(tree: Tree[_, _]) = (tree ne null) && tree.isBlack + + private[this] def blacken[A, B](t: Tree[A, B]): Tree[A, B] = if (t eq null) null else t.black + + // Blacken if the tree is red and has a red child. This is necessary when using methods such as `upd` or `updNth` + // for building subtrees. Use `blacken` instead when building top-level trees. + private[this] def maybeBlacken[A, B](t: Tree[A, B]): Tree[A, B] = + if(isBlack(t)) t else if(isRedTree(t.left) || isRedTree(t.right)) t.black else t + + private[this] def mkTree[A, B](isBlack: Boolean, key: A, value: B, left: Tree[A, B], right: Tree[A, B]) = { + val sizeAndColour = sizeOf(left) + sizeOf(right) + 1 | (if(isBlack) initialBlackCount else initialRedCount) + new Tree(key, value.asInstanceOf[AnyRef], left, right, sizeAndColour) + } + + /** Create a new balanced tree where `newLeft` replaces `tree.left`. */ + private[this] def balanceLeft[A, B1](tree: Tree[A, B1], newLeft: Tree[A, B1]): Tree[A, B1] = { + // Parameter trees + // tree | newLeft + // -- KV R | nl.L nl.KV nl.R + // | nl.R.L nl.R.KV nl.R.R + if (tree.left eq newLeft) tree + else { + if (newLeft.isRed) { + val newLeft_left = newLeft.left + val newLeft_right = newLeft.right + if (isRedTree(newLeft_left)) { + // RED + // black(nl.L) nl.KV black + // nl.R KV R + val resultLeft = newLeft_left.black + val resultRight = tree.blackWithLeft(newLeft_right) + + newLeft.withLeftRight(resultLeft, resultRight) + } else if (isRedTree(newLeft_right)) { + // RED + // black nl.R.KV black + // nl.L nl.KV nl.R.L nl.R.R KV R + val newLeft_right_right = newLeft_right.right + + val resultLeft = newLeft.blackWithRight(newLeft_right.left) + val resultRight = tree.blackWithLeft(newLeft_right_right) + + newLeft_right.withLeftRight(resultLeft, resultRight) + } else { + // tree + // newLeft KV R + tree.withLeft(newLeft) + } + } else { + // tree + // newLeft KV R + tree.withLeft(newLeft) + } + } + } + /** Create a new balanced tree where `newRight` replaces `tree.right`. */ + private[this] def balanceRight[A, B1](tree: Tree[A, B1], newRight: Tree[A, B1]): Tree[A, B1] = { + // Parameter trees + // tree | newRight + // L KV -- | nr.L nr.KV nr.R + // | nr.L.L nr.L.KV nr.L.R + if (tree.right eq newRight) tree + else { + if (newRight.isRed) { + val newRight_left = newRight.left + if (isRedTree(newRight_left)) { + // RED + // black nr.L.KV black + // L KV nr.L.L nr.L.R nr.KV nr.R + val resultLeft = tree.blackWithRight(newRight_left.left) + val resultRight = newRight.blackWithLeft(newRight_left.right) + + newRight_left.withLeftRight(resultLeft, resultRight) + } else { + val newRight_right = newRight.right + if (isRedTree(newRight_right)) { + // RED + // black nr.KV black(nr.R) + // L KV nr.L + val resultLeft = tree.blackWithRight(newRight_left) + val resultRight = newRight_right.black + + newRight.withLeftRight(resultLeft, resultRight) + } else { + // tree + // L KV newRight + tree.withRight(newRight) + } + } + } else { + // tree + // L KV newRight + tree.withRight(newRight) + } + } + } + + private[this] def upd[A, B, B1 >: B](tree: Tree[A, B], k: A, v: B1, overwrite: Boolean)(implicit ordering: Ordering[A]): Tree[A, B1] = if (tree eq null) { + RedTree(k, v, null, null) + } else if (k.asInstanceOf[AnyRef] eq tree.key.asInstanceOf[AnyRef]) { + if (overwrite) + tree.withV(v) + else tree + } else { + val cmp = ordering.compare(k, tree.key) + if (cmp < 0) + balanceLeft(tree, upd(tree.left, k, v, overwrite)) + else if (cmp > 0) + balanceRight(tree, upd(tree.right, k, v, overwrite)) + else if (overwrite && (v.asInstanceOf[AnyRef] ne tree.value.asInstanceOf[AnyRef])) + tree.withV(v) + else tree + } + private[this] def updNth[A, B, B1 >: B](tree: Tree[A, B], idx: Int, k: A, v: B1): Tree[A, B1] = if (tree eq null) { + RedTree(k, v, null, null) + } else { + val rank = count(tree.left) + 1 + if (idx < rank) + balanceLeft(tree, updNth(tree.left, idx, k, v)) + else if (idx > rank) + balanceRight(tree, updNth(tree.right, idx - rank, k, v)) + else tree + } + + private[this] def doFrom[A, B](tree: Tree[A, B], from: A)(implicit ordering: Ordering[A]): Tree[A, B] = { + if (tree eq null) return null + if (ordering.lt(tree.key, from)) return doFrom(tree.right, from) + val newLeft = doFrom(tree.left, from) + if (newLeft eq tree.left) tree + else if (newLeft eq null) upd(tree.right, tree.key, tree.value, overwrite = false) + else join(newLeft, tree.key, tree.value, tree.right) + } + private[this] def doTo[A, B](tree: Tree[A, B], to: A)(implicit ordering: Ordering[A]): Tree[A, B] = { + if (tree eq null) return null + if (ordering.lt(to, tree.key)) return doTo(tree.left, to) + val newRight = doTo(tree.right, to) + if (newRight eq tree.right) tree + else if (newRight eq null) upd(tree.left, tree.key, tree.value, overwrite = false) + else join (tree.left, tree.key, tree.value, newRight) + } + private[this] def doUntil[A, B](tree: Tree[A, B], until: A)(implicit ordering: Ordering[A]): Tree[A, B] = { + if (tree eq null) return null + if (ordering.lteq(until, tree.key)) return doUntil(tree.left, until) + val newRight = doUntil(tree.right, until) + if (newRight eq tree.right) tree + else if (newRight eq null) upd(tree.left, tree.key, tree.value, overwrite = false) + else join(tree.left, tree.key, tree.value, newRight) + } + + private[this] def doRange[A, B](tree: Tree[A, B], from: A, until: A)(implicit ordering: Ordering[A]): Tree[A, B] = { + if (tree eq null) return null + if (ordering.lt(tree.key, from)) return doRange(tree.right, from, until) + if (ordering.lteq(until, tree.key)) return doRange(tree.left, from, until) + val newLeft = doFrom(tree.left, from) + val newRight = doUntil(tree.right, until) + if ((newLeft eq tree.left) && (newRight eq tree.right)) tree + else if (newLeft eq null) upd(newRight, tree.key, tree.value, overwrite = false) + else if (newRight eq null) upd(newLeft, tree.key, tree.value, overwrite = false) + else join(newLeft, tree.key, tree.value, newRight) + } + + private[this] def doDrop[A, B](tree: Tree[A, B], n: Int): Tree[A, B] = + if((tree eq null) || (n <= 0)) tree + else if(n >= tree.count) null + else { + val l = count(tree.left) + if(n > l) doDrop(tree.right, n-l-1) + else if(n == l) join(null, tree.key, tree.value, tree.right) + else join(doDrop(tree.left, n), tree.key, tree.value, tree.right) + } + + private[this] def doTake[A, B](tree: Tree[A, B], n: Int): Tree[A, B] = + if((tree eq null) || (n <= 0)) null + else if(n >= tree.count) tree + else { + val l = count(tree.left) + if(n <= l) doTake(tree.left, n) + else if(n == l+1) maybeBlacken(updNth(tree.left, n, tree.key, tree.value)) + else join(tree.left, tree.key, tree.value, doTake(tree.right, n-l-1)) + } + + private[this] def doSlice[A, B](tree: Tree[A, B], from: Int, until: Int): Tree[A, B] = + if((tree eq null) || (from >= until) || (from >= tree.count) || (until <= 0)) null + else if((from <= 0) && (until >= tree.count)) tree + else { + val l = count(tree.left) + if(until <= l) doSlice(tree.left, from, until) + else if(from > l) doSlice(tree.right, from-l-1, until-l-1) + else join(doDrop(tree.left, from), tree.key, tree.value, doTake(tree.right, until-l-1)) + } + + /* + * Forcing direct fields access using the @`inline` annotation helps speed up + * various operations (especially smallest/greatest and update/delete). + * + * Unfortunately the direct field access is not guaranteed to work (but + * works on the current implementation of the Scala compiler). + * + * An alternative is to implement the these classes using plain old Java code... + * + * Mutability + * This implementation encodes both mutable and immutable trees. + * Mutable trees are never exposed to the user code but we get significant reductions in both CPU and allocations + * by maintaining a mutable tree during internal operations, e.g. a builder building a Tree, and the other bulk + * API such as filter or ++ + * + * Mutable trees are only used within the confines of this bulk operation and not shared + * Mutable trees may transition to become immutable by calling beforePublish + * Mutable trees may have child nodes (left and right) which are immutable Trees (this promotes structural sharing) + * + * Immutable trees may only child nodes (left and right) which are immutable Trees, and as such the immutable + * trees the entire transitive subtree is immutable + * + * Colour, mutablity and size encoding + * The colour of the Tree, its mutablity and size are all encoded in the _count field + * The colour is encoded in the top bit (31) of the _count. This allows a mutable tree to change colour without + * additional allocation + * The mutable trees always have bits 0 .. 30 (inclusive) set to 0 + * The immutable trees always have bits 0 .. 30 containing the size of the transitive subtree + * + * Naming + * All of the methods that can yield a mutable result have "mutable" on their name, and generally there + * is another method similarly named with doesn't. This is to aid safety and to reduce the cognitive load when + * reviewing changes. e.g. + * def upd(...) will update an immutable Tree, producing an immutable Tree + * def mutableUpd(...) will update a mutable or immutable Tree and may return a mutable or immutable Tree + * a method that has mutable in its name may return a immutable tree if the operation can reuse the existing tree + * + */ + private[immutable] final class Tree[A, +B]( + @(`inline` @getter @setter) private var _key: A, + @(`inline` @getter @setter) private var _value: AnyRef, + @(`inline` @getter @setter) private var _left: Tree[A, _], + @(`inline` @getter @setter) private var _right: Tree[A, _], + @(`inline` @getter @setter) private var _count: Int) + { + @`inline` private[RedBlackTree] def isMutable: Boolean = (_count & colourMask) == 0 + // read only APIs + @`inline` private[RedBlackTree] final def count = { + //devTimeAssert((_count & 0x7FFFFFFF) != 0) + _count & colourMask + } + //retain the colour, and mark as mutable + @`inline` private def mutableRetainingColour = _count & colourBit + + //inlined here to avoid outer object null checks + @`inline` private[RedBlackTree] final def sizeOf(tree:Tree[_,_]) = if (tree eq null) 0 else tree.count + @`inline` private[immutable] final def key = _key + @`inline` private[immutable] final def value = _value.asInstanceOf[B] + @`inline` private[immutable] final def left = _left.asInstanceOf[Tree[A, B]] + @`inline` private[immutable] final def right = _right.asInstanceOf[Tree[A, B]] + //Note - only used in tests outside RedBlackTree + @`inline` private[immutable] final def isBlack = _count < 0 + //Note - only used in tests outside RedBlackTree + @`inline` private[immutable] final def isRed = _count >= 0 + + override def toString: String = s"${if(isRed) "RedTree" else "BlackTree"}($key, $value, $left, $right)" + + //mutable APIs + private[RedBlackTree] def makeImmutable: Tree[A, B] = { + def makeImmutableImpl() = { + if (isMutable) { + var size = 1 + if (_left ne null) { + _left.makeImmutable + size += _left.count + } + if (_right ne null) { + _right.makeImmutable + size += _right.count + } + _count |= size //retains colour + } + this + } + makeImmutableImpl() + this + } + + private[RedBlackTree] def mutableBlack: Tree[A, B] = { + if (isBlack) this + else if (isMutable) { + _count = initialBlackCount + this + } + else new Tree(_key, _value, _left, _right, initialBlackCount) + } +// private[RedBlackTree] def mutableRed: Tree[A, B] = { +// if (isRed) this +// else if (mutable) { +// _count = initialRedCount +// this +// } +// else new Tree(_key, _value, _left, _right, initialRedCount) +// } + + private[RedBlackTree] def mutableWithV[B1 >: B](newValue: B1): Tree[A, B1] = { + if (newValue.asInstanceOf[AnyRef] eq _value.asInstanceOf[AnyRef]) this + else if (isMutable) { + _value = newValue.asInstanceOf[AnyRef] + this + } else new Tree(_key, newValue.asInstanceOf[AnyRef], _left, _right, mutableRetainingColour) + } + + private[RedBlackTree] def mutableWithLeft[B1 >: B](newLeft: Tree[A, B1]): Tree[A, B1] = { + if (_left eq newLeft) this + else if (isMutable) { + _left = newLeft + this + } else new Tree(_key, _value, newLeft, _right, mutableRetainingColour) + } + private[RedBlackTree] def mutableWithRight[B1 >: B](newRight: Tree[A, B1]): Tree[A, B1] = { + if (_right eq newRight) this + else if (isMutable) { + _right = newRight + this + } else new Tree(_key, _value, _left, newRight, mutableRetainingColour) + } + private[RedBlackTree] def mutableWithLeftRight[B1 >: B](newLeft: Tree[A, B1], newRight: Tree[A, B1]): Tree[A, B1] = { + if ((_left eq newLeft) && (_right eq newRight)) this + else if (isMutable) { + _left = newLeft + _right = newRight + this + } else new Tree(_key, _value, newLeft, newRight, mutableRetainingColour) + } + private[RedBlackTree] def mutableBlackWithLeft[B1 >: B](newLeft: Tree[A, B1]): Tree[A, B1] = { + if ((_left eq newLeft) && isBlack) this + else if (isMutable) { + _count = initialBlackCount + _left = newLeft + this + } else new Tree(_key, _value, newLeft, _right, initialBlackCount) + } + private[RedBlackTree] def mutableBlackWithRight[B1 >: B](newRight: Tree[A, B1]): Tree[A, B1] = { + if ((_right eq newRight) && isBlack) this + else if (isMutable) { + _count = initialBlackCount + _right = newRight + this + } else new Tree(_key, _value, _left, newRight, initialBlackCount) + } + + private[RedBlackTree] def black: Tree[A, B] = { + //assertNotMutable(this) + if (isBlack) this + else new Tree(_key, _value, _left, _right, _count ^ colourBit) + } + private[RedBlackTree] def red: Tree[A, B] = { + //assertNotMutable(this) + if (isRed) this + else new Tree(_key, _value, _left, _right, _count ^ colourBit) + } + private[RedBlackTree] def withKV[B1 >: B](newKey: A, newValue: B1): Tree[A, B1] = { + //assertNotMutable(this) + if ((newKey.asInstanceOf[AnyRef] eq _key.asInstanceOf[AnyRef]) && + (newValue.asInstanceOf[AnyRef] eq _value.asInstanceOf[AnyRef])) this + else new Tree(newKey, newValue.asInstanceOf[AnyRef], _left, _right, _count) + } + private[RedBlackTree] def withV[B1 >: B](newValue: B1): Tree[A, B1] = { + //assertNotMutable(this) + if (newValue.asInstanceOf[AnyRef] eq _value.asInstanceOf[AnyRef]) this + else new Tree(_key, newValue.asInstanceOf[AnyRef], _left, _right, _count) + } + + private[RedBlackTree] def withLeft[B1 >: B](newLeft: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + if (newLeft eq _left) this + else { + val size = sizeOf(newLeft) + sizeOf(_right) + 1 + new Tree(key, value.asInstanceOf[AnyRef], newLeft, _right, (_count & colourBit) | size) + } + } + private[RedBlackTree] def withRight[B1 >: B](newRight: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newRight) + if (newRight eq _right) this + else { + val size = sizeOf(_left) + sizeOf(newRight) + 1 + new Tree(key, value.asInstanceOf[AnyRef], _left, newRight, (_count & colourBit) | size) + } + } + private[RedBlackTree] def blackWithLeft[B1 >: B](newLeft: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + if ((newLeft eq _left) && isBlack) this + else { + val size = sizeOf(newLeft) + sizeOf(_right) + 1 + new Tree(key, value.asInstanceOf[AnyRef], newLeft, _right, initialBlackCount | size) + } + } + private[RedBlackTree] def redWithLeft[B1 >: B](newLeft: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + if ((newLeft eq _left) && isRed) this + else { + val size = sizeOf(newLeft) + sizeOf(_right) + 1 + new Tree(key, value.asInstanceOf[AnyRef], newLeft, _right, initialRedCount | size) + } + } + private[RedBlackTree] def blackWithRight[B1 >: B](newRight: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newRight) + if ((newRight eq _right) && isBlack) this + else { + val size = sizeOf(_left) + sizeOf(newRight) + 1 + new Tree(key, value.asInstanceOf[AnyRef], _left, newRight, initialBlackCount | size) + } + } + private[RedBlackTree] def redWithRight[B1 >: B](newRight: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + if ((newRight eq _right) && isRed) this + else { + val size = sizeOf(_left) + sizeOf(newRight) + 1 + new Tree(key, value.asInstanceOf[AnyRef], _left, newRight, initialRedCount | size) + } + } + private[RedBlackTree] def withLeftRight[B1 >: B](newLeft: Tree[A, B1], newRight: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + //assertNotMutable(newRight) + if ((newLeft eq _left) && (newRight eq _right)) this + else { + val size = sizeOf(newLeft) + sizeOf(newRight) + 1 + new Tree(key, value.asInstanceOf[AnyRef], newLeft, newRight, (_count & colourBit) | size) + } + } + private[RedBlackTree] def redWithLeftRight[B1 >: B](newLeft: Tree[A, B1], newRight: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + //assertNotMutable(newRight) + if ((newLeft eq _left) && (newRight eq _right) && isRed) this + else { + val size = sizeOf(newLeft) + sizeOf(newRight) + 1 + new Tree(key, value.asInstanceOf[AnyRef], newLeft, newRight, initialRedCount | size) + } + } + private[RedBlackTree] def blackWithLeftRight[B1 >: B](newLeft: Tree[A, B1], newRight: Tree[A, B1]): Tree[A, B1] = { + //assertNotMutable(this) + //assertNotMutable(newLeft) + //assertNotMutable(newRight) + if ((newLeft eq _left) && (newRight eq _right) && isBlack) this + else { + val size = sizeOf(newLeft) + sizeOf(newRight) + 1 + new Tree(key, value.asInstanceOf[AnyRef], newLeft, newRight, initialBlackCount | size) + } + } + } + //see #Tree docs "Colour, mutablity and size encoding" + //we make these final vals because the optimiser inlines them, without reference to the enclosing module + private[RedBlackTree] final val colourBit = 0x80000000 + //really its ~colourBit but that doesnt get inlined + private[RedBlackTree] final val colourMask = colourBit - 1 + private[RedBlackTree] final val initialBlackCount = colourBit + private[RedBlackTree] final val initialRedCount = 0 + + @`inline` private[RedBlackTree] def mutableRedTree[A, B](key: A, value: B, left: Tree[A, B], right: Tree[A, B]) = new Tree[A,B](key, value.asInstanceOf[AnyRef], left, right, initialRedCount) + @`inline` private[RedBlackTree] def mutableBlackTree[A, B](key: A, value: B, left: Tree[A, B], right: Tree[A, B]) = new Tree[A,B](key, value.asInstanceOf[AnyRef], left, right, initialBlackCount) + + /** create a new immutable red tree. + * left and right may be null + */ + private[immutable] def RedTree[A, B](key: A, value: B, left: Tree[A, B], right: Tree[A, B]): Tree[A, B] = { + //assertNotMutable(left) + //assertNotMutable(right) + val size = sizeOf(left) + sizeOf(right) + 1 + new Tree(key, value.asInstanceOf[AnyRef], left, right, initialRedCount | size) + } + private[immutable] def BlackTree[A, B](key: A, value: B, left: Tree[A, B], right: Tree[A, B]): Tree[A, B] = { + //assertNotMutable(left) + //assertNotMutable(right) + val size = sizeOf(left) + sizeOf(right) + 1 + new Tree(key, value.asInstanceOf[AnyRef], left, right, initialBlackCount | size) + } + @`inline` private def sizeOf(tree:Tree[_,_]) = if (tree eq null) 0 else tree.count + //immutable APIs + //assertions - uncomment decls and callers when changing functionality + // private def devTimeAssert(assertion: Boolean) = { + // //uncomment this during development of the functionality + // assert(assertion) + // } + // private def assertNotMutable(t:Tree[_,_]) = { + // devTimeAssert ((t eq null) || t.count > 0) + // } + private[this] abstract class TreeIterator[A, B, R](root: Tree[A, B], start: Option[A])(protected implicit val ordering: Ordering[A]) extends AbstractIterator[R] { + protected[this] def nextResult(tree: Tree[A, B]): R + + override def hasNext: Boolean = lookahead ne null + + @throws[NoSuchElementException] + override def next(): R = { + val tree = lookahead + if(tree ne null) { + lookahead = findLeftMostOrPopOnEmpty(goRight(tree)) + nextResult(tree) + } else Iterator.empty.next() + } + + @tailrec + protected final def findLeftMostOrPopOnEmpty(tree: Tree[A, B]): Tree[A, B] = + if (tree eq null) popNext() + else if (tree.left eq null) tree + else findLeftMostOrPopOnEmpty(goLeft(tree)) + + @`inline` private[this] def pushNext(tree: Tree[A, B]): Unit = { + stackOfNexts(index) = tree + index += 1 + } + @`inline` protected final def popNext(): Tree[A, B] = if (index == 0) null else { + index -= 1 + stackOfNexts(index) + } + + protected[this] val stackOfNexts = if (root eq null) null else { + /* + * According to "Ralf Hinze. Constructing red-black trees" [https://www.cs.ox.ac.uk/ralf.hinze/publications/#P5] + * the maximum height of a red-black tree is 2*log_2(n + 2) - 2. + * + * According to {@see Integer#numberOfLeadingZeros} ceil(log_2(n)) = (32 - Integer.numberOfLeadingZeros(n - 1)) + * + * Although we don't store the deepest nodes in the path during iteration, + * we potentially do so in `startFrom`. + */ + val maximumHeight = 2 * (32 - Integer.numberOfLeadingZeros(root.count + 2 - 1)) - 2 + new Array[Tree[A, B] @uncheckedCaptures](maximumHeight) + } + private[this] var index = 0 + protected var lookahead: Tree[A, B] @uncheckedCaptures = + if (start.isDefined) startFrom(start.get) else findLeftMostOrPopOnEmpty(root) + + /** + * Find the leftmost subtree whose key is equal to the given key, or if no such thing, + * the leftmost subtree with the key that would be "next" after it according + * to the ordering. Along the way build up the iterator's path stack so that "next" + * functionality works. + */ + private[this] def startFrom(key: A) : Tree[A,B] = if (root eq null) null else { + @tailrec def find(tree: Tree[A, B]): Tree[A, B] = + if (tree eq null) popNext() + else find( + if (ordering.lteq(key, tree.key)) goLeft(tree) + else goRight(tree) + ) + find(root) + } + + @`inline` private[this] def goLeft(tree: Tree[A, B]) = { + pushNext(tree) + tree.left + } + + @`inline` protected final def goRight(tree: Tree[A, B]) = tree.right + } + + private[this] class EqualsIterator[A: Ordering, B](tree: Tree[A, B]) extends TreeIterator[A, B, Unit](tree, None) { + override def nextResult(tree: Tree[A, B]) = ??? + + def sameKeys[X](that:EqualsIterator[A,X]): Boolean = { + var equal = true + while (equal && (this.lookahead ne null) && (that.lookahead ne null)) { + if (this.lookahead eq that.lookahead) { + this.lookahead = this.popNext() + that.lookahead = that.popNext() + } else { + equal = (this.lookahead.key.asInstanceOf[AnyRef] eq that.lookahead.key.asInstanceOf[AnyRef]) || + ordering.equiv(this.lookahead.key, that.lookahead.key) + this.lookahead = this.findLeftMostOrPopOnEmpty(this.goRight(this.lookahead)) + that.lookahead = that.findLeftMostOrPopOnEmpty(that.goRight(that.lookahead)) + } + } + equal && (this.lookahead eq null) && (that.lookahead eq null) + } + def sameValues[X](that:EqualsIterator[A,X]): Boolean = { + var equal = true + while (equal && (this.lookahead ne null) && (that.lookahead ne null)) { + if (this.lookahead eq that.lookahead) { + this.lookahead = this.popNext() + that.lookahead = that.popNext() + } else { + equal = this.lookahead.value == that.lookahead.value + this.lookahead = this.findLeftMostOrPopOnEmpty(this.goRight(this.lookahead)) + that.lookahead = that.findLeftMostOrPopOnEmpty(that.goRight(that.lookahead)) + } + } + equal && (this.lookahead eq null) && (that.lookahead eq null) + } + def sameEntries[X](that:EqualsIterator[A,X]): Boolean = { + var equal = true + while (equal && (this.lookahead ne null) && (that.lookahead ne null)) { + if (this.lookahead eq that.lookahead) { + this.lookahead = this.popNext() + that.lookahead = that.popNext() + } else { + equal = ((this.lookahead.key.asInstanceOf[AnyRef] eq that.lookahead.key.asInstanceOf[AnyRef]) || + ordering.equiv(this.lookahead.key, that.lookahead.key)) && this.lookahead.value == that.lookahead.value + this.lookahead = this.findLeftMostOrPopOnEmpty(this.goRight(this.lookahead)) + that.lookahead = that.findLeftMostOrPopOnEmpty(that.goRight(that.lookahead)) + } + } + equal && (this.lookahead eq null) && (that.lookahead eq null) + } + } + private[this] class EntriesIterator[A: Ordering, B](tree: Tree[A, B], focus: Option[A]) extends TreeIterator[A, B, (A, B)](tree, focus) { + override def nextResult(tree: Tree[A, B]) = (tree.key, tree.value) + } + + private[this] class KeysIterator[A: Ordering, B](tree: Tree[A, B], focus: Option[A]) extends TreeIterator[A, B, A](tree, focus) { + override def nextResult(tree: Tree[A, B]) = tree.key + } + + private[this] class ValuesIterator[A: Ordering, B](tree: Tree[A, B], focus: Option[A]) extends TreeIterator[A, B, B](tree, focus) { + override def nextResult(tree: Tree[A, B]) = tree.value + } + + /** Build a Tree suitable for a TreeSet from an ordered sequence of keys */ + def fromOrderedKeys[A](xs: Iterator[A], size: Int): Tree[A, Null] = { + val maxUsedDepth = 32 - Integer.numberOfLeadingZeros(size) // maximum depth of non-leaf nodes + def f(level: Int, size: Int): Tree[A, Null] = size match { + case 0 => null + case 1 => mkTree(level != maxUsedDepth || level == 1, xs.next(), null, null, null) + case n => + val leftSize = (size-1)/2 + val left = f(level+1, leftSize) + val x = xs.next() + val right = f(level+1, size-1-leftSize) + BlackTree(x, null, left, right) + } + f(1, size) + } + + /** Build a Tree suitable for a TreeMap from an ordered sequence of key/value pairs */ + def fromOrderedEntries[A, B](xs: Iterator[(A, B)], size: Int): Tree[A, B] = { + val maxUsedDepth = 32 - Integer.numberOfLeadingZeros(size) // maximum depth of non-leaf nodes + def f(level: Int, size: Int): Tree[A, B] = size match { + case 0 => null + case 1 => + val (k, v) = xs.next() + mkTree(level != maxUsedDepth || level == 1, k, v, null, null) + case n => + val leftSize = (size-1)/2 + val left = f(level+1, leftSize) + val (k, v) = xs.next() + val right = f(level+1, size-1-leftSize) + BlackTree(k, v, left, right) + } + f(1, size) + } + + def transform[A, B, C](t: Tree[A, B], f: (A, B) => C): Tree[A, C] = + if(t eq null) null + else { + val k = t.key + val v = t.value + val l = t.left + val r = t.right + val l2 = transform(l, f) + val v2 = f(k, v) + val r2 = transform(r, f) + if((v2.asInstanceOf[AnyRef] eq v.asInstanceOf[AnyRef]) + && (l2 eq l) + && (r2 eq r)) t.asInstanceOf[Tree[A, C]] + else mkTree(t.isBlack, k, v2, l2, r2) + } + + def filterEntries[A, B](t: Tree[A, B], f: (A, B) => Boolean): Tree[A, B] = if(t eq null) null else { + def fk(t: Tree[A, B]): Tree[A, B] = { + val k = t.key + val v = t.value + val l = t.left + val r = t.right + val l2 = if(l eq null) null else fk(l) + val keep = f(k, v) + val r2 = if(r eq null) null else fk(r) + if(!keep) join2(l2, r2) + else if((l2 eq l) && (r2 eq r)) t + else join(l2, k, v, r2) + } + blacken(fk(t)) + } + + private[this] val null2 = (null, null) + + def partitionEntries[A, B](t: Tree[A, B], p: (A, B) => Boolean): (Tree[A, B], Tree[A, B]) = if(t eq null) (null, null) else { + if (t eq null) null2 + else { + object partitioner { + var tmpk, tmpd = null: Tree[A, B] // shared vars to avoid returning tuples from fk + def fk(t: Tree[A, B]): Unit = { + val k = t.key + val v = t.value + val l = t.left + val r = t.right + var l2k, l2d, r2k, r2d = null: Tree[A, B] + if (l ne null) { + fk(l) + l2k = tmpk + l2d = tmpd + } + val keep = p(k, v) + if (r ne null) { + fk(r) + r2k = tmpk + r2d = tmpd + } + val jk = + if (!keep) join2(l2k, r2k) + else if ((l2k eq l) && (r2k eq r)) t + else join(l2k, k, v, r2k) + val jd = + if (keep) join2(l2d, r2d) + else if ((l2d eq l) && (r2d eq r)) t + else join(l2d, k, v, r2d) + tmpk = jk + tmpd = jd + } + } + + partitioner.fk(t) + (blacken(partitioner.tmpk), blacken(partitioner.tmpd)) + } + } + + // Based on Stefan Kahrs' Haskell version of Okasaki's Red&Black Trees + // Constructing Red-Black Trees, Ralf Hinze: [[https://www.cs.ox.ac.uk/ralf.hinze/publications/WAAAPL99b.ps.gz]] + // Red-Black Trees in a Functional Setting, Chris Okasaki: [[https://wiki.rice.edu/confluence/download/attachments/2761212/Okasaki-Red-Black.pdf]] */ + + private[this] def del[A, B](tree: Tree[A, B], k: A)(implicit ordering: Ordering[A]): Tree[A, B] = if (tree eq null) null else { + val cmp = ordering.compare(k, tree.key) + if (cmp < 0) { + val newLeft = del(tree.left, k) + if (newLeft eq tree.left) tree + else if (isBlackTree(tree.left)) balLeft(tree, newLeft, tree.right) + else tree.redWithLeft(newLeft) + } else if (cmp > 0) { + val newRight = del(tree.right, k) + if (newRight eq tree.right) tree + else if (isBlackTree(tree.right)) balRight(tree, tree.left, newRight) + else tree.redWithRight(newRight) + } else append(tree.left, tree.right) + } + + private[this] def balance[A, B](tree: Tree[A,B], tl: Tree[A, B], tr: Tree[A, B]): Tree[A, B] = + if (isRedTree(tl)) { + if (isRedTree(tr)) tree.redWithLeftRight(tl.black, tr.black) + else if (isRedTree(tl.left)) tl.withLeftRight(tl.left.black, tree.blackWithLeftRight(tl.right, tr)) + else if (isRedTree(tl.right)) tl.right.withLeftRight(tl.blackWithRight(tl.right.left), tree.blackWithLeftRight(tl.right.right, tr)) + else tree.blackWithLeftRight(tl, tr) + } else if (isRedTree(tr)) { + if (isRedTree(tr.right)) tr.withLeftRight(tree.blackWithLeftRight(tl, tr.left), tr.right.black) + else if (isRedTree(tr.left)) tr.left.withLeftRight(tree.blackWithLeftRight(tl, tr.left.left), tr.blackWithLeftRight(tr.left.right, tr.right)) + else tree.blackWithLeftRight(tl, tr) + } else tree.blackWithLeftRight(tl, tr) + + private[this] def balLeft[A, B](tree: Tree[A,B], tl: Tree[A, B], tr: Tree[A, B]): Tree[A, B] = + if (isRedTree(tl)) tree.redWithLeftRight(tl.black, tr) + else if (isBlackTree(tr)) balance(tree, tl, tr.red) + else if (isRedTree(tr) && isBlackTree(tr.left)) + tr.left.redWithLeftRight(tree.blackWithLeftRight(tl, tr.left.left), balance(tr, tr.left.right, tr.right.red)) + else sys.error("Defect: invariance violation") + + private[this] def balRight[A, B](tree: Tree[A,B], tl: Tree[A, B], tr: Tree[A, B]): Tree[A, B] = + if (isRedTree(tr)) tree.redWithLeftRight(tl, tr.black) + else if (isBlackTree(tl)) balance(tree, tl.red, tr) + else if (isRedTree(tl) && isBlackTree(tl.right)) + tl.right.redWithLeftRight(balance(tl, tl.left.red, tl.right.left), tree.blackWithLeftRight(tl.right.right, tr)) + else sys.error("Defect: invariance violation") + + /** `append` is similar to `join2` but requires that both subtrees have the same black height */ + private[this] def append[A, B](tl: Tree[A, B], tr: Tree[A, B]): Tree[A, B] = { + if (tl eq null) tr + else if (tr eq null) tl + else if (tl.isRed) { + if (tr.isRed) { + //tl is red, tr is red + val bc = append(tl.right, tr.left) + if (isRedTree(bc)) bc.withLeftRight(tl.withRight(bc.left), tr.withLeft(bc.right)) + else tl.withRight(tr.withLeft(bc)) + } else { + //tl is red, tr is black + tl.withRight(append(tl.right, tr)) + } + } else { + if (tr.isBlack) { + //tl is black tr is black + val bc = append(tl.right, tr.left) + if (isRedTree(bc)) bc.withLeftRight(tl.withRight(bc.left), tr.withLeft(bc.right)) + else balLeft(tl, tl.left, tr.withLeft(bc)) + } else { + //tl is black tr is red + tr.withLeft(append(tl, tr.left)) + } + } + } + + + // Bulk operations based on "Just Join for Parallel Ordered Sets" (https://www.cs.cmu.edu/~guyb/papers/BFS16.pdf) + // We don't store the black height in the tree so we pass it down into the join methods and derive the black height + // of child nodes from it. Where possible the black height is used directly instead of deriving the rank from it. + // Our trees are supposed to have a black root so we always blacken as the last step of union/intersect/difference. + + def union[A, B](t1: Tree[A, B], t2: Tree[A, B])(implicit ordering: Ordering[A]): Tree[A, B] = blacken(_union(t1, t2)) + + def intersect[A, B](t1: Tree[A, B], t2: Tree[A, B])(implicit ordering: Ordering[A]): Tree[A, B] = blacken(_intersect(t1, t2)) + + def difference[A, B](t1: Tree[A, B], t2: Tree[A, _])(implicit ordering: Ordering[A]): Tree[A, B] = + blacken(_difference(t1, t2.asInstanceOf[Tree[A, B]])) + + /** Compute the rank from a tree and its black height */ + @`inline` private[this] def rank(t: Tree[_, _], bh: Int): Int = { + if(t eq null) 0 + else if(t.isBlack) 2*(bh-1) + else 2*bh-1 + } + + private[this] def joinRight[A, B](tl: Tree[A, B], k: A, v: B, tr: Tree[A, B], bhtl: Int, rtr: Int): Tree[A, B] = { + val rtl = rank(tl, bhtl) + if(rtl == (rtr/2)*2) RedTree(k, v, tl, tr) + else { + val tlBlack = isBlackTree(tl) + val bhtlr = if(tlBlack) bhtl-1 else bhtl + val ttr = joinRight(tl.right, k, v, tr, bhtlr, rtr) + if(tlBlack && isRedTree(ttr) && isRedTree(ttr.right)) + RedTree(ttr.key, ttr.value, + BlackTree(tl.key, tl.value, tl.left, ttr.left), + ttr.right.black) + else mkTree(tlBlack, tl.key, tl.value, tl.left, ttr) + } + } + + private[this] def joinLeft[A, B](tl: Tree[A, B], k: A, v: B, tr: Tree[A, B], rtl: Int, bhtr: Int): Tree[A, B] = { + val rtr = rank(tr, bhtr) + if(rtr == (rtl/2)*2) RedTree(k, v, tl, tr) + else { + val trBlack = isBlackTree(tr) + val bhtrl = if(trBlack) bhtr-1 else bhtr + val ttl = joinLeft(tl, k, v, tr.left, rtl, bhtrl) + if(trBlack && isRedTree(ttl) && isRedTree(ttl.left)) + RedTree(ttl.key, ttl.value, + ttl.left.black, + BlackTree(tr.key, tr.value, ttl.right, tr.right)) + else mkTree(trBlack, tr.key, tr.value, ttl, tr.right) + } + } + + private[this] def join[A, B](tl: Tree[A, B], k: A, v: B, tr: Tree[A, B]): Tree[A, B] = { + @tailrec def h(t: Tree[_, _], i: Int): Int = + if(t eq null) i+1 else h(t.left, if(t.isBlack) i+1 else i) + val bhtl = h(tl, 0) + val bhtr = h(tr, 0) + if(bhtl > bhtr) { + val tt = joinRight(tl, k, v, tr, bhtl, rank(tr, bhtr)) + if(isRedTree(tt) && isRedTree(tt.right)) tt.black + else tt + } else if(bhtr > bhtl) { + val tt = joinLeft(tl, k, v, tr, rank(tl, bhtl), bhtr) + if(isRedTree(tt) && isRedTree(tt.left)) tt.black + else tt + } else mkTree(isRedTree(tl) || isRedTree(tr), k, v, tl, tr) + } + + private[this] def split[A, B](t: Tree[A, B], k2: A)(implicit ordering: Ordering[A]): (Tree[A, B], Tree[A, B], Tree[A, B], A) = + if(t eq null) (null, null, null, k2) + else { + val cmp = ordering.compare(k2, t.key) + if(cmp == 0) (t.left, t, t.right, t.key) + else if(cmp < 0) { + val (ll, b, lr, k1) = split(t.left, k2) + (ll, b, join(lr, t.key, t.value, t.right), k1) + } else { + val (rl, b, rr, k1) = split(t.right, k2) + (join(t.left, t.key, t.value, rl), b, rr, k1) + } + } + + private[this] def splitLast[A, B](t: Tree[A, B]): (Tree[A, B], A, B) = + if(t.right eq null) (t.left, t.key, t.value) + else { + val (tt, kk, vv) = splitLast(t.right) + (join(t.left, t.key, t.value, tt), kk, vv) + } + + private[this] def join2[A, B](tl: Tree[A, B], tr: Tree[A, B]): Tree[A, B] = + if(tl eq null) tr + else if(tr eq null) tl + else { + val (ttl, k, v) = splitLast(tl) + join(ttl, k, v, tr) + } + + private[this] def _union[A, B](t1: Tree[A, B], t2: Tree[A, B])(implicit ordering: Ordering[A]): Tree[A, B] = + if((t1 eq null) || (t1 eq t2)) t2 + else if(t2 eq null) t1 + else { + val (l1, _, r1, k1) = split(t1, t2.key) + val tl = _union(l1, t2.left) + val tr = _union(r1, t2.right) + join(tl, k1, t2.value, tr) + } + + private[this] def _intersect[A, B](t1: Tree[A, B], t2: Tree[A, B])(implicit ordering: Ordering[A]): Tree[A, B] = + if((t1 eq null) || (t2 eq null)) null + else if (t1 eq t2) t1 + else { + val (l1, b, r1, k1) = split(t1, t2.key) + val tl = _intersect(l1, t2.left) + val tr = _intersect(r1, t2.right) + if(b ne null) join(tl, k1, t2.value, tr) + else join2(tl, tr) + } + + private[this] def _difference[A, B](t1: Tree[A, B], t2: Tree[A, B])(implicit ordering: Ordering[A]): Tree[A, B] = + if((t1 eq null) || (t2 eq null)) t1 + else if (t1 eq t2) null + else { + val (l1, _, r1, k1) = split(t1, t2.key) + val tl = _difference(l1, t2.left) + val tr = _difference(r1, t2.right) + join2(tl, tr) + } +} From d526e10754018f3fb25cf4798e864f9caaf2d05d Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 11:46:11 +0100 Subject: [PATCH 71/89] Add immutable SeqMap to stdlib --- .../stdlib/collection/immutable/SeqMap.scala | 278 ++++++++++++++++++ 1 file changed, 278 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/SeqMap.scala diff --git a/tests/pos-special/stdlib/collection/immutable/SeqMap.scala b/tests/pos-special/stdlib/collection/immutable/SeqMap.scala new file mode 100644 index 000000000000..6c955fd52fc2 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/SeqMap.scala @@ -0,0 +1,278 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.collection.mutable.{Builder, ReusableBuilder} +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** A base trait for ordered, immutable maps. + * + * Note that the [[equals]] method for [[SeqMap]] compares key-value pairs + * without regard to ordering. + * + * All behavior is defined in terms of the abstract methods in `SeqMap`. + * It is sufficient for concrete subclasses to implement those methods. + * Methods that return a new map, in particular [[removed]] and [[updated]], must preserve ordering. + * + * @tparam K the type of the keys contained in this linked map. + * @tparam V the type of the values associated with the keys in this linked map. + * + * @define coll immutable seq map + * @define Coll `immutable.SeqMap` + */ + +trait SeqMap[K, +V] + extends Map[K, V] + with collection.SeqMap[K, V] + with MapOps[K, V, SeqMap, SeqMap[K, V]] + with MapFactoryDefaults[K, V, SeqMap, Iterable] { + override def mapFactory: MapFactory[SeqMap] = SeqMap +} + + +object SeqMap extends MapFactory[SeqMap] { + def empty[K, V]: SeqMap[K, V] = EmptySeqMap.asInstanceOf[SeqMap[K, V]] + + def from[K, V](it: collection.IterableOnce[(K, V)]^): SeqMap[K, V] = + it match { + case sm: SeqMap[K, V] => sm + case _ => (newBuilder[K, V] ++= it).result() + } + + def newBuilder[K, V]: Builder[(K, V), SeqMap[K, V]] = new SeqMapBuilderImpl + + @SerialVersionUID(3L) + private object EmptySeqMap extends SeqMap[Any, Nothing] with Serializable { + override def size: Int = 0 + override def knownSize: Int = 0 + override def apply(key: Any) = throw new NoSuchElementException("key not found: " + key) + override def contains(key: Any) = false + def get(key: Any): Option[Nothing] = None + override def getOrElse [V1](key: Any, default: => V1): V1 = default + def iterator: Iterator[(Any, Nothing)] = Iterator.empty + def updated [V1] (key: Any, value: V1): SeqMap[Any, V1] = new SeqMap1(key, value) + def removed(key: Any): SeqMap[Any, Nothing] = this + } + + @SerialVersionUID(3L) + private final class SeqMap1[K, +V](key1: K, value1: V) extends SeqMap[K,V] with Serializable { + override def size: Int = 1 + override def knownSize: Int = 1 + override def apply(key: K) = if (key == key1) value1 else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K) = key == key1 + def get(key: K): Option[V] = + if (key == key1) Some(value1) else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 else default + def iterator = Iterator.single((key1, value1)) + def updated[V1 >: V](key: K, value: V1): SeqMap[K, V1] = + if (key == key1) new SeqMap1(key1, value) + else new SeqMap2(key1, value1, key, value) + def removed(key: K): SeqMap[K, V] = + if (key == key1) SeqMap.empty else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)) + } + override def foreachEntry[U](f: (K, V) => U): Unit = { + f(key1, value1) + } + } + + @SerialVersionUID(3L) + private final class SeqMap2[K, +V](key1: K, value1: V, key2: K, value2: V) extends SeqMap[K,V] with Serializable { + override def size: Int = 2 + override def knownSize: Int = 2 + override def apply(key: K) = + if (key == key1) value1 + else if (key == key2) value2 + else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K) = (key == key1) || (key == key2) + def get(key: K): Option[V] = + if (key == key1) Some(value1) + else if (key == key2) Some(value2) + else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 + else if (key == key2) value2 + else default + def iterator = ((key1, value1) :: (key2, value2) :: Nil).iterator + def updated[V1 >: V](key: K, value: V1): SeqMap[K, V1] = + if (key == key1) new SeqMap2(key1, value, key2, value2) + else if (key == key2) new SeqMap2(key1, value1, key2, value) + else new SeqMap3(key1, value1, key2, value2, key, value) + def removed(key: K): SeqMap[K, V] = + if (key == key1) new SeqMap1(key2, value2) + else if (key == key2) new SeqMap1(key1, value1) + else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)); f((key2, value2)) + } + override def foreachEntry[U](f: (K, V) => U): Unit = { + f(key1, value1) + f(key2, value2) + } + } + + @SerialVersionUID(3L) + private class SeqMap3[K, +V](key1: K, value1: V, key2: K, value2: V, key3: K, value3: V) extends SeqMap[K,V] with Serializable { + override def size: Int = 3 + override def knownSize: Int = 3 + override def apply(key: K) = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K) = (key == key1) || (key == key2) || (key == key3) + def get(key: K): Option[V] = + if (key == key1) Some(value1) + else if (key == key2) Some(value2) + else if (key == key3) Some(value3) + else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else default + def iterator = ((key1, value1) :: (key2, value2) :: (key3, value3) :: Nil).iterator + def updated[V1 >: V](key: K, value: V1): SeqMap[K, V1] = + if (key == key1) new SeqMap3(key1, value, key2, value2, key3, value3) + else if (key == key2) new SeqMap3(key1, value1, key2, value, key3, value3) + else if (key == key3) new SeqMap3(key1, value1, key2, value2, key3, value) + else new SeqMap4(key1, value1, key2, value2, key3, value3, key, value) + def removed(key: K): SeqMap[K, V] = + if (key == key1) new SeqMap2(key2, value2, key3, value3) + else if (key == key2) new SeqMap2(key1, value1, key3, value3) + else if (key == key3) new SeqMap2(key1, value1, key2, value2) + else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)); f((key2, value2)); f((key3, value3)) + } + override def foreachEntry[U](f: (K, V) => U): Unit = { + f(key1, value1) + f(key2, value2) + f(key3, value3) + } + } + + @SerialVersionUID(3L) + private final class SeqMap4[K, +V](key1: K, value1: V, key2: K, value2: V, key3: K, value3: V, key4: K, value4: V) extends SeqMap[K,V] with Serializable { + override def size: Int = 4 + override def knownSize: Int = 4 + override def apply(key: K) = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else if (key == key4) value4 + else throw new NoSuchElementException("key not found: " + key) + override def contains(key: K) = (key == key1) || (key == key2) || (key == key3) || (key == key4) + def get(key: K): Option[V] = + if (key == key1) Some(value1) + else if (key == key2) Some(value2) + else if (key == key3) Some(value3) + else if (key == key4) Some(value4) + else None + override def getOrElse [V1 >: V](key: K, default: => V1): V1 = + if (key == key1) value1 + else if (key == key2) value2 + else if (key == key3) value3 + else if (key == key4) value4 + else default + def iterator = ((key1, value1) :: (key2, value2) :: (key3, value3) :: (key4, value4) :: Nil).iterator + def updated[V1 >: V](key: K, value: V1): SeqMap[K, V1] = + if (key == key1) new SeqMap4(key1, value, key2, value2, key3, value3, key4, value4) + else if (key == key2) new SeqMap4(key1, value1, key2, value, key3, value3, key4, value4) + else if (key == key3) new SeqMap4(key1, value1, key2, value2, key3, value, key4, value4) + else if (key == key4) new SeqMap4(key1, value1, key2, value2, key3, value3, key4, value) + else { + // Directly create the elements for performance reasons + val fields = Vector(key1, key2, key3, key4, key) + val underlying: Map[K, (Int, V1)] = + HashMap( + (key1, (0, value1)), + (key2, (1, value2)), + (key3, (2, value3)), + (key4, (3, value4)), + (key, (4, value)) + ) + new VectorMap(fields, underlying) + } + def removed(key: K): SeqMap[K, V] = + if (key == key1) new SeqMap3(key2, value2, key3, value3, key4, value4) + else if (key == key2) new SeqMap3(key1, value1, key3, value3, key4, value4) + else if (key == key3) new SeqMap3(key1, value1, key2, value2, key4, value4) + else if (key == key4) new SeqMap3(key1, value1, key2, value2, key3, value3) + else this + override def foreach[U](f: ((K, V)) => U): Unit = { + f((key1, value1)); f((key2, value2)); f((key3, value3)); f((key4, value4)) + } + override def foreachEntry[U](f: (K, V) => U): Unit = { + f(key1, value1) + f(key2, value2) + f(key3, value3) + f(key4, value4) + } + + private[SeqMap] def buildTo[V1 >: V](builder: Builder[(K, V1), SeqMap[K, V1]]): builder.type = + builder.addOne((key1, value1)).addOne((key2, value2)).addOne((key3, value3)).addOne((key4, value4)) + } + + private final class SeqMapBuilderImpl[K, V] extends ReusableBuilder[(K, V), SeqMap[K, V]] { + private[this] var elems: SeqMap[K, V] @uncheckedCaptures = SeqMap.empty + private[this] var switchedToVectorMapBuilder: Boolean = false + private[this] var vectorMapBuilder: VectorMapBuilder[K, V] @uncheckedCaptures = _ + + override def clear(): Unit = { + elems = SeqMap.empty + if (vectorMapBuilder != null) { + vectorMapBuilder.clear() + } + switchedToVectorMapBuilder = false + } + + override def result(): SeqMap[K, V] = + if (switchedToVectorMapBuilder) vectorMapBuilder.result() else elems + + def addOne(elem: (K, V)) = { + if (switchedToVectorMapBuilder) { + vectorMapBuilder.addOne(elem) + } else if (elems.size < 4) { + elems = elems + elem + } else { + // assert(elems.size == 4) + if (elems.contains(elem._1)) { + elems = elems + elem // will not increase the size of the map + } else { + switchedToVectorMapBuilder = true + if (vectorMapBuilder == null) { + vectorMapBuilder = new VectorMapBuilder + } + elems.asInstanceOf[SeqMap4[K, V]].buildTo(vectorMapBuilder) + vectorMapBuilder.addOne(elem) + } + } + + this + } + + override def addAll(xs: IterableOnce[(K, V)]^): this.type = + if (switchedToVectorMapBuilder) { + vectorMapBuilder.addAll(xs) + this + } else { + super.addAll(xs) + } + } +} From 26dde726255cef3d899cabe7508b1aa207d904ef Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 11:48:52 +0100 Subject: [PATCH 72/89] Add immutable SortedMap to stdlib --- .../collection/immutable/SortedMap.scala | 178 ++++++++++++++++++ 1 file changed, 178 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/SortedMap.scala diff --git a/tests/pos-special/stdlib/collection/immutable/SortedMap.scala b/tests/pos-special/stdlib/collection/immutable/SortedMap.scala new file mode 100644 index 000000000000..9587502fd908 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/SortedMap.scala @@ -0,0 +1,178 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.unchecked.uncheckedVariance +import scala.collection.mutable.Builder +import language.experimental.captureChecking + +/** An immutable map whose key-value pairs are sorted according to an [[scala.math.Ordering]] on the keys. + * + * Allows for range queries to be performed on its keys, and implementations must guarantee that traversal happens in + * sorted order, according to the map's [[scala.math.Ordering]]. + * + * @example {{{ + * import scala.collection.immutable.SortedMap + * + * // Make a SortedMap via the companion object factory + * val weekdays = SortedMap( + * 2 -> "Monday", + * 3 -> "Tuesday", + * 4 -> "Wednesday", + * 5 -> "Thursday", + * 6 -> "Friday" + * ) + * // TreeMap(2 -> Monday, 3 -> Tuesday, 4 -> Wednesday, 5 -> Thursday, 6 -> Friday) + * + * val days = weekdays ++ List(1 -> "Sunday", 7 -> "Saturday") + * // TreeMap(1 -> Sunday, 2 -> Monday, 3 -> Tuesday, 4 -> Wednesday, 5 -> Thursday, 6 -> Friday, 7 -> Saturday) + * + * val day3 = days.get(3) // Some("Tuesday") + * + * val rangeOfDays = days.range(2, 5) // TreeMap(2 -> Monday, 3 -> Tuesday, 4 -> Wednesday) + * + * val daysUntil2 = days.rangeUntil(2) // TreeMap(1 -> Sunday) + * val daysTo2 = days.rangeTo(2) // TreeMap(1 -> Sunday, 2 -> Monday) + * val daysAfter5 = days.rangeFrom(5) // TreeMap(5 -> Thursday, 6 -> Friday, 7 -> Saturday) + * }}} + * + * @tparam K the type of the keys contained in this tree map. + * @tparam V the type of the values associated with the keys. + */ +trait SortedMap[K, +V] + extends Map[K, V] + with collection.SortedMap[K, V] + with SortedMapOps[K, V, SortedMap, SortedMap[K, V]] + with SortedMapFactoryDefaults[K, V, SortedMap, Iterable, Map] { + + override def unsorted: Map[K, V] = this + + override def sortedMapFactory: SortedMapFactory[SortedMap] = SortedMap + + /** The same map with a given default function. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefault`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d the function mapping keys to values, used for non-present keys + * @return a wrapper of the map with a default value + */ + override def withDefault[V1 >: V](d: K -> V1): SortedMap[K, V1] = new SortedMap.WithDefault[K, V1](this, d) + + /** The same map with a given default value. + * Note: The default is only used for `apply`. Other methods like `get`, `contains`, `iterator`, `keys`, etc. + * are not affected by `withDefaultValue`. + * + * Invoking transformer methods (e.g. `map`) will not preserve the default value. + * + * @param d default value used for non-present keys + * @return a wrapper of the map with a default value + */ + override def withDefaultValue[V1 >: V](d: V1): SortedMap[K, V1] = new SortedMap.WithDefault[K, V1](this, _ => d) +} + +trait SortedMapOps[K, +V, +CC[X, +Y] <: Map[X, Y] with SortedMapOps[X, Y, CC, _], +C <: SortedMapOps[K, V, CC, C]] + extends MapOps[K, V, Map, C] with collection.SortedMapOps[K, V, CC, C] { self => + + protected def coll: C with CC[K, V] + + def unsorted: Map[K, V] + + override def keySet: SortedSet[K] = new ImmutableKeySortedSet + + /** The implementation class of the set returned by `keySet` */ + protected class ImmutableKeySortedSet extends AbstractSet[K] with SortedSet[K] with GenKeySet with GenKeySortedSet { + def rangeImpl(from: Option[K], until: Option[K]): SortedSet[K] = { + val map = self.rangeImpl(from, until) + new map.ImmutableKeySortedSet + } + def incl(elem: K): SortedSet[K] = fromSpecific(this).incl(elem) + def excl(elem: K): SortedSet[K] = fromSpecific(this).excl(elem) + } + + // We override these methods to fix their return type (which would be `Map` otherwise) + def updated[V1 >: V](key: K, value: V1): CC[K, V1] + @`inline` final override def +[V1 >: V](kv: (K, V1)): CC[K, V1] = updated(kv._1, kv._2) + override def updatedWith[V1 >: V](key: K)(remappingFunction: Option[V] => Option[V1]): CC[K, V1] = { + // Implementation has been copied from `MapOps` + val previousValue = this.get(key) + remappingFunction(previousValue) match { + case None => previousValue.fold(coll)(_ => this.removed(key).coll) + case Some(nextValue) => + if (previousValue.exists(_.asInstanceOf[AnyRef] eq nextValue.asInstanceOf[AnyRef])) coll + else coll.updated(key, nextValue) + } + } + override def transform[W](f: (K, V) => W): CC[K, W] = map({ case (k, v) => (k, f(k, v)) })(ordering) +} + +trait StrictOptimizedSortedMapOps[K, +V, +CC[X, +Y] <: Map[X, Y] with SortedMapOps[X, Y, CC, _], +C <: SortedMapOps[K, V, CC, C]] + extends SortedMapOps[K, V, CC, C] + with collection.StrictOptimizedSortedMapOps[K, V, CC, C] + with StrictOptimizedMapOps[K, V, Map, C] { + + override def concat[V2 >: V](xs: collection.IterableOnce[(K, V2)]^): CC[K, V2] = { + var result: CC[K, V2] = coll + val it = xs.iterator + while (it.hasNext) result = result + it.next() + result + } +} + +@SerialVersionUID(3L) +object SortedMap extends SortedMapFactory.Delegate[SortedMap](TreeMap) { + + override def from[K: Ordering, V](it: IterableOnce[(K, V)]^): SortedMap[K, V] = it match { + case sm: SortedMap[K, V] if Ordering[K] == sm.ordering => sm + case _ => super.from(it) + } + + final class WithDefault[K, +V](underlying: SortedMap[K, V], defaultValue: K -> V) + extends Map.WithDefault[K, V](underlying, defaultValue) + with SortedMap[K, V] + with SortedMapOps[K, V, SortedMap, WithDefault[K, V]] with Serializable { + + implicit def ordering: Ordering[K] = underlying.ordering + + override def sortedMapFactory: SortedMapFactory[SortedMap] = underlying.sortedMapFactory + + def iteratorFrom(start: K): scala.collection.Iterator[(K, V)] = underlying.iteratorFrom(start) + + def keysIteratorFrom(start: K): scala.collection.Iterator[K] = underlying.keysIteratorFrom(start) + + def rangeImpl(from: Option[K], until: Option[K]): WithDefault[K, V] = + new WithDefault[K, V](underlying.rangeImpl(from, until), defaultValue) + + // Need to override following methods to match type signatures of `SortedMap.WithDefault` + // for operations preserving default value + + override def updated[V1 >: V](key: K, value: V1): WithDefault[K, V1] = + new WithDefault[K, V1](underlying.updated(key, value), defaultValue) + + override def concat [V2 >: V](xs: collection.IterableOnce[(K, V2)]^): WithDefault[K, V2] = + new WithDefault( underlying.concat(xs) , defaultValue) + + override def removed(key: K): WithDefault[K, V] = new WithDefault[K, V](underlying.removed(key), defaultValue) + + override def empty: WithDefault[K, V] = new WithDefault[K, V](underlying.empty, defaultValue) + + override protected def fromSpecific(coll: scala.collection.IterableOnce[(K, V) @uncheckedVariance]^): WithDefault[K, V] = + new WithDefault[K, V](sortedMapFactory.from(coll), defaultValue) + + override protected def newSpecificBuilder: Builder[(K, V), WithDefault[K, V]] @uncheckedVariance = + SortedMap.newBuilder.mapResult((p: SortedMap[K, V]) => new WithDefault[K, V](p, defaultValue)) + } +} From a08460ddfe2faab8e3c86776857334e3a63b37be Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 11:57:10 +0100 Subject: [PATCH 73/89] Add immutable StrictOptimizedSeqOps to stdlib --- .../collection/StrictOptimizedSeqOps.scala | 2 +- .../stdlib/collection/immutable/Seq.scala | 2 +- .../immutable/StrictOptimizedSeqOps.scala | 82 +++++++++++++++++++ 3 files changed, 84 insertions(+), 2 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/immutable/StrictOptimizedSeqOps.scala diff --git a/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala b/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala index 7a5c58bf2abf..bfea9eda8bd3 100644 --- a/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala +++ b/tests/pos-special/stdlib/collection/StrictOptimizedSeqOps.scala @@ -19,7 +19,7 @@ import scala.annotation.unchecked.uncheckedCaptures * to take advantage of strict builders. */ trait StrictOptimizedSeqOps [+A, +CC[_], +C] - extends AnyRef + extends Any with SeqOps[A, CC, C] with StrictOptimizedIterableOps[A, CC, C] { diff --git a/tests/pos-special/stdlib/collection/immutable/Seq.scala b/tests/pos-special/stdlib/collection/immutable/Seq.scala index 5184cadaccae..d575c3aaf14a 100644 --- a/tests/pos-special/stdlib/collection/immutable/Seq.scala +++ b/tests/pos-special/stdlib/collection/immutable/Seq.scala @@ -30,7 +30,7 @@ trait Seq[+A] extends Iterable[A] * @define coll immutable sequence * @define Coll `immutable.Seq` */ -trait SeqOps[+A, +CC[_], +C] extends AnyRef with collection.SeqOps[A, CC, C] +trait SeqOps[+A, +CC[_], +C] extends Any with collection.SeqOps[A, CC, C] /** * $factoryInfo diff --git a/tests/pos-special/stdlib/collection/immutable/StrictOptimizedSeqOps.scala b/tests/pos-special/stdlib/collection/immutable/StrictOptimizedSeqOps.scala new file mode 100644 index 000000000000..b1e4622971fb --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/StrictOptimizedSeqOps.scala @@ -0,0 +1,82 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable +import language.experimental.captureChecking +import annotation.unchecked.uncheckedCaptures + +/** + * Trait that overrides operations to take advantage of strict builders. + */ +trait StrictOptimizedSeqOps[+A, +CC[_], +C] + extends Any + with SeqOps[A, CC, C] + with collection.StrictOptimizedSeqOps[A, CC, C] + with StrictOptimizedIterableOps[A, CC, C] { + + override def distinctBy[B](f: A -> B): C = { + if (lengthCompare(1) <= 0) coll + else { + val builder = newSpecificBuilder + val seen = mutable.HashSet.empty[B @uncheckedCaptures] + val it = this.iterator + var different = false + while (it.hasNext) { + val next = it.next() + if (seen.add(f(next))) builder += next else different = true + } + if (different) builder.result() else coll + } + } + + override def updated[B >: A](index: Int, elem: B): CC[B] = { + if (index < 0) throw new IndexOutOfBoundsException(s"$index is out of bounds (min 0, max ${if (knownSize>=0) knownSize else "unknown"})") + val b = iterableFactory.newBuilder[B] + if (knownSize >= 0) { + b.sizeHint(size) + } + var i = 0 + val it = iterator + while (i < index && it.hasNext) { + b += it.next() + i += 1 + } + if (!it.hasNext) throw new IndexOutOfBoundsException(s"$index is out of bounds (min 0, max ${i-1})") + b += elem + it.next() + while (it.hasNext) b += it.next() + b.result() + } + + override def patch[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): CC[B] = { + val b = iterableFactory.newBuilder[B] + var i = 0 + val it = iterator + while (i < from && it.hasNext) { + b += it.next() + i += 1 + } + b ++= other + i = replaced + while (i > 0 && it.hasNext) { + it.next() + i -= 1 + } + while (it.hasNext) b += it.next() + b.result() + } + + override def sorted[B >: A](implicit ord: Ordering[B]): C = super.sorted(ord) + +} From c66c833eb9b4b7a8677d7a437b94e7e395b8989a Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 12:05:57 +0100 Subject: [PATCH 74/89] Add Vector and VectorMap to stdlib --- .../stdlib/collection/immutable/Vector.scala | 2476 +++++++++++++++++ .../collection/immutable/VectorMap.scala | 277 ++ 2 files changed, 2753 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/Vector.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/VectorMap.scala diff --git a/tests/pos-special/stdlib/collection/immutable/Vector.scala b/tests/pos-special/stdlib/collection/immutable/Vector.scala new file mode 100644 index 000000000000..1bde30406fd9 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/Vector.scala @@ -0,0 +1,2476 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package immutable + +import java.lang.Math.{abs, max => mmax, min => mmin} +import java.util.Arrays.{copyOf, copyOfRange} +import java.util.{Arrays, Spliterator} + +import scala.annotation.switch +import scala.annotation.unchecked.uncheckedVariance +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.immutable.VectorInline._ +import scala.collection.immutable.VectorStatics._ +import scala.collection.mutable.ReusableBuilder +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + + +/** $factoryInfo + * @define Coll `Vector` + * @define coll vector + */ +@SerialVersionUID(3L) +object Vector extends StrictOptimizedSeqFactory[Vector] { + + def empty[A]: Vector[A] = Vector0 + + def from[E](it: collection.IterableOnce[E]^): Vector[E] = + it match { + case v: Vector[E] => v + case _ => + val knownSize = it.knownSize + if (knownSize == 0) empty[E] + else if (knownSize > 0 && knownSize <= WIDTH) { + val a1: Arr1 = it match { + case as: ArraySeq.ofRef[_] if as.elemTag.runtimeClass == classOf[AnyRef] => + as.unsafeArray.asInstanceOf[Arr1] + case it: Iterable[E] => + val a1 = new Arr1(knownSize) + it.copyToArray(a1.asInstanceOf[Array[Any]]) + a1 + case _ => + val a1 = new Arr1(knownSize) + it.iterator.copyToArray(a1.asInstanceOf[Array[Any]]) + a1.asInstanceOf[Arr1] + } + new Vector1[E](a1) + } else { + (newBuilder ++= it).result() + } + } + + def newBuilder[A]: ReusableBuilder[A, Vector[A]] = new VectorBuilder[A] + + /** Create a Vector with the same element at each index. + * + * Unlike `fill`, which takes a by-name argument for the value and can thereby + * compute different values for each index, this method guarantees that all + * elements are identical. This allows sparse allocation in O(log n) time and space. + */ + private[collection] def fillSparse[A](n: Int)(elem: A): Vector[A] = { + //TODO Make public; this method is private for now because it is not forward binary compatible + if(n <= 0) Vector0 + else { + val b = new VectorBuilder[A] + b.initSparse(n, elem) + b.result() + } + } + + private val defaultApplyPreferredMaxLength: Int = + try System.getProperty("scala.collection.immutable.Vector.defaultApplyPreferredMaxLength", + "250").toInt + catch { + case _: SecurityException => 250 + } + + private val emptyIterator = new NewVectorIterator(Vector0, 0, 0) +} + + +/** Vector is a general-purpose, immutable data structure. It provides random access and updates + * in O(log n) time, as well as very fast append/prepend/tail/init (amortized O(1), worst case O(log n)). + * Because vectors strike a good balance between fast random selections and fast random functional updates, + * they are currently the default implementation of immutable indexed sequences. + * + * Vectors are implemented by radix-balanced finger trees of width 32. There is a separate subclass + * for each level (0 to 6, with 0 being the empty vector and 6 a tree with a maximum width of 64 at the + * top level). + * + * Tree balancing: + * - Only the first dimension of an array may have a size < WIDTH + * - In a `data` (central) array the first dimension may be up to WIDTH-2 long, in `prefix1` and `suffix1` up + * to WIDTH, and in other `prefix` and `suffix` arrays up to WIDTH-1 + * - `prefix1` and `suffix1` are never empty + * - Balancing does not cross the main data array (i.e. prepending never touches the suffix and appending never touches + * the prefix). The level is increased/decreased when the affected side plus main data is already full/empty + * - All arrays are left-aligned and truncated + * + * In addition to the data slices (`prefix1`, `prefix2`, ..., `dataN`, ..., `suffix2`, `suffix1`) we store a running + * count of elements after each prefix for more efficient indexing without having to dereference all prefix arrays. + */ +sealed abstract class Vector[+A] private[immutable] (private[immutable] final val prefix1: Arr1) + extends AbstractSeq[A] + with IndexedSeq[A] + with IndexedSeqOps[A, Vector, Vector[A]] + with StrictOptimizedSeqOps[A, Vector, Vector[A]] + with IterableFactoryDefaults[A, Vector] + with DefaultSerializable { + + override def iterableFactory: SeqFactory[Vector] = Vector + + override final def length: Int = + if(this.isInstanceOf[BigVector[_]]) this.asInstanceOf[BigVector[_]].length0 + else prefix1.length + + override final def iterator: Iterator[A] = + if(this.isInstanceOf[Vector0.type]) Vector.emptyIterator + else new NewVectorIterator(this, length, vectorSliceCount) + + override final protected[collection] def filterImpl(pred: A => Boolean, isFlipped: Boolean): Vector[A] = { + var i = 0 + val len = prefix1.length + while (i != len) { + if (pred(prefix1(i).asInstanceOf[A]) == isFlipped) { + // each 1 bit indicates that index passes the filter. + // all indices < i are also assumed to pass the filter + var bitmap = 0 + var j = i + 1 + while (j < len) { + if (pred(prefix1(j).asInstanceOf[A]) != isFlipped) { + bitmap |= (1 << j) + } + j += 1 + } + val newLen = i + java.lang.Integer.bitCount(bitmap) + + if(this.isInstanceOf[BigVector[_]]) { + val b = new VectorBuilder[A] + var k = 0 + while(k < i) { + b.addOne(prefix1(k).asInstanceOf[A]) + k += 1 + } + k = i + 1 + while (i != newLen) { + if (((1 << k) & bitmap) != 0) { + b.addOne(prefix1(k).asInstanceOf[A]) + i += 1 + } + k += 1 + } + this.asInstanceOf[BigVector[A]].foreachRest { v => if(pred(v) != isFlipped) b.addOne(v) } + return b.result() + } else { + if (newLen == 0) return Vector0 + val newData = new Array[AnyRef](newLen) + System.arraycopy(prefix1, 0, newData, 0, i) + var k = i + 1 + while (i != newLen) { + if (((1 << k) & bitmap) != 0) { + newData(i) = prefix1(k) + i += 1 + } + k += 1 + } + return new Vector1[A](newData) + } + } + i += 1 + } + if(this.isInstanceOf[BigVector[_]]) { + val b = new VectorBuilder[A] + b.initFrom(prefix1) + this.asInstanceOf[BigVector[A]].foreachRest { v => if(pred(v) != isFlipped) b.addOne(v) } + b.result() + } else this + } + + // Dummy overrides to refine result types for binary compatibility: + override def updated[B >: A](index: Int, elem: B): Vector[B] = super.updated(index, elem) + override def appended[B >: A](elem: B): Vector[B] = super.appended(elem) + override def prepended[B >: A](elem: B): Vector[B] = super.prepended(elem) + override def prependedAll[B >: A](prefix: collection.IterableOnce[B]^): Vector[B] = { + val k = prefix.knownSize + if (k == 0) this + else if (k < 0) super.prependedAll(prefix) + else prependedAll0(prefix, k) + } + + override final def appendedAll[B >: A](suffix: collection.IterableOnce[B]^): Vector[B] = { + val k = suffix.knownSize + if (k == 0) this + else if (k < 0) super.appendedAll(suffix) + else appendedAll0(suffix, k) + } + + protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + // k >= 0, k = prefix.knownSize + val tinyAppendLimit = 4 + vectorSliceCount + if (k < tinyAppendLimit /*|| k < (this.size >>> Log2ConcatFaster)*/) { + var v: Vector[B] = this + val it = IndexedSeq.from(prefix).reverseIterator + while (it.hasNext) v = it.next() +: v + v + } else if (this.size < (k >>> Log2ConcatFaster) && prefix.isInstanceOf[Vector[_]]) { + var v = prefix.asInstanceOf[Vector[B]] + val it = this.iterator + while (it.hasNext) v = v :+ it.next() + v + } else if (k < this.size - AlignToFaster) { + new VectorBuilder[B].alignTo(k, this).addAll(prefix).addAll(this).result() + } else super.prependedAll(prefix) + } + + protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + // k >= 0, k = suffix.knownSize + val tinyAppendLimit = 4 + vectorSliceCount + if (k < tinyAppendLimit) { + var v: Vector[B] = this + suffix match { + case it: Iterable[_] => it.asInstanceOf[Iterable[B]].foreach(x => v = v.appended(x)) + case _ => suffix.iterator.foreach(x => v = v.appended(x)) + } + v + } else if (this.size < (k >>> Log2ConcatFaster) && suffix.isInstanceOf[Vector[_]]) { + var v = suffix.asInstanceOf[Vector[B]] + val ri = this.reverseIterator + while (ri.hasNext) v = v.prepended(ri.next()) + v + } else if (this.size < k - AlignToFaster && suffix.isInstanceOf[Vector[_]]) { + val v = suffix.asInstanceOf[Vector[B]] + new VectorBuilder[B].alignTo(this.size, v).addAll(this).addAll(v).result() + } else new VectorBuilder[B].initFrom(this).addAll(suffix).result() + } + + override def className = "Vector" + + @inline override final def take(n: Int): Vector[A] = slice(0, n) + @inline override final def drop(n: Int): Vector[A] = slice(n, length) + @inline override final def takeRight(n: Int): Vector[A] = slice(length - mmax(n, 0), length) + @inline override final def dropRight(n: Int): Vector[A] = slice(0, length - mmax(n, 0)) + override def tail: Vector[A] = slice(1, length) + override def init: Vector[A] = slice(0, length-1) + + /** Like slice but parameters must be 0 <= lo < hi < length */ + protected[this] def slice0(lo: Int, hi: Int): Vector[A] + + /** Number of slices */ + protected[immutable] def vectorSliceCount: Int + /** Slice at index */ + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] + /** Length of all slices up to and including index */ + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int + + override def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = iterator.copyToArray(xs, start, len) + + override def toVector: Vector[A] = this + + override protected def applyPreferredMaxLength: Int = Vector.defaultApplyPreferredMaxLength + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + val s = shape.shape match { + case StepperShape.IntShape => new IntVectorStepper(iterator.asInstanceOf[NewVectorIterator[Int]]) + case StepperShape.LongShape => new LongVectorStepper(iterator.asInstanceOf[NewVectorIterator[Long]]) + case StepperShape.DoubleShape => new DoubleVectorStepper(iterator.asInstanceOf[NewVectorIterator[Double]]) + case _ => shape.parUnbox(new AnyVectorStepper[A](iterator.asInstanceOf[NewVectorIterator[A]])) + } + s.asInstanceOf[S with EfficientSplit] + } + + protected[this] def ioob(index: Int): IndexOutOfBoundsException = + new IndexOutOfBoundsException(s"$index is out of bounds (min 0, max ${length-1})") + + override final def head: A = + if (prefix1.length == 0) throw new NoSuchElementException("empty.head") + else prefix1(0).asInstanceOf[A] + + override final def last: A = { + if(this.isInstanceOf[BigVector[_]]) { + val suffix = this.asInstanceOf[BigVector[_]].suffix1 + if(suffix.length == 0) throw new NoSuchElementException("empty.tail") + else suffix(suffix.length-1) + } else prefix1(prefix1.length-1) + }.asInstanceOf[A] + + override final def foreach[U](f: A => U): Unit = { + val c = vectorSliceCount + var i = 0 + while (i < c) { + foreachRec(vectorSliceDim(c, i) - 1, vectorSlice(i), f) + i += 1 + } + } + + // The following definitions are needed for binary compatibility with ParVector + private[collection] def startIndex: Int = 0 + private[collection] def endIndex: Int = length + private[collection] def initIterator[B >: A](s: VectorIterator[B]): Unit = + s.it = iterator.asInstanceOf[NewVectorIterator[B]] +} + + +/** This class only exists because we cannot override `slice` in `Vector` in a binary-compatible way */ +private sealed abstract class VectorImpl[+A](_prefix1: Arr1) extends Vector[A](_prefix1) { + + override final def slice(from: Int, until: Int): Vector[A] = { + val lo = mmax(from, 0) + val hi = mmin(until, length) + if (hi <= lo) Vector0 + else if (hi - lo == length) this + else slice0(lo, hi) + } +} + + +/** Vector with suffix and length fields; all Vector subclasses except Vector1 extend this */ +private sealed abstract class BigVector[+A](_prefix1: Arr1, private[immutable] val suffix1: Arr1, private[immutable] val length0: Int) extends VectorImpl[A](_prefix1) { + + protected[immutable] final def foreachRest[U](f: A => U): Unit = { + val c = vectorSliceCount + var i = 1 + while(i < c) { + foreachRec(vectorSliceDim(c, i)-1, vectorSlice(i), f) + i += 1 + } + } +} + + +/** Empty vector */ +private object Vector0 extends BigVector[Nothing](empty1, empty1, 0) { + + def apply(index: Int): Nothing = throw ioob(index) + + override def updated[B >: Nothing](index: Int, elem: B): Vector[B] = throw ioob(index) + + override def appended[B >: Nothing](elem: B): Vector[B] = new Vector1(wrap1(elem)) + + override def prepended[B >: Nothing](elem: B): Vector[B] = new Vector1(wrap1(elem)) + + override def map[B](f: Nothing => B): Vector[B] = this + + override def tail: Vector[Nothing] = throw new UnsupportedOperationException("empty.tail") + + override def init: Vector[Nothing] = throw new UnsupportedOperationException("empty.init") + + protected[this] def slice0(lo: Int, hi: Int): Vector[Nothing] = this + + protected[immutable] def vectorSliceCount: Int = 0 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = null + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = 0 + + override def equals(o: Any): Boolean = { + if(this eq o.asInstanceOf[AnyRef]) true + else o match { + case that: Vector[_] => false + case o => super.equals(o) + } + } + + override protected[this]def prependedAll0[B >: Nothing](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + Vector.from(prefix) + + override protected[this]def appendedAll0[B >: Nothing](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = + Vector.from(suffix) + + override protected[this] def ioob(index: Int): IndexOutOfBoundsException = + new IndexOutOfBoundsException(s"$index is out of bounds (empty vector)") +} + +/** Flat ArraySeq-like structure */ +private final class Vector1[+A](_data1: Arr1) extends VectorImpl[A](_data1) { + + @inline def apply(index: Int): A = { + if(index >= 0 && index < prefix1.length) + prefix1(index).asInstanceOf[A] + else throw ioob(index) + } + + override def updated[B >: A](index: Int, elem: B): Vector[B] = { + if(index >= 0 && index < prefix1.length) + new Vector1(copyUpdate(prefix1, index, elem)) + else throw ioob(index) + } + + override def appended[B >: A](elem: B): Vector[B] = { + val len1 = prefix1.length + if(len1 < WIDTH) new Vector1(copyAppend1(prefix1, elem)) + else new Vector2(prefix1, WIDTH, empty2, wrap1(elem), WIDTH+1) + } + + override def prepended[B >: A](elem: B): Vector[B] = { + val len1 = prefix1.length + if(len1 < WIDTH) new Vector1(copyPrepend1(elem, prefix1)) + else new Vector2(wrap1(elem), 1, empty2, prefix1, len1+1) + } + + override def map[B](f: A => B): Vector[B] = new Vector1(mapElems1(prefix1, f)) + + protected[this] def slice0(lo: Int, hi: Int): Vector[A] = + new Vector1(copyOfRange(prefix1, lo, hi)) + + override def tail: Vector[A] = + if(prefix1.length == 1) Vector0 + else new Vector1(copyTail(prefix1)) + + override def init: Vector[A] = + if(prefix1.length == 1) Vector0 + else new Vector1(copyInit(prefix1)) + + protected[immutable] def vectorSliceCount: Int = 1 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = prefix1 + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = prefix1.length + + override protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + prepend1IfSpace(prefix1, prefix) match { + case null => super.prependedAll0(prefix, k) + case data1b => new Vector1(data1b) + } + + override protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + val data1b = append1IfSpace(prefix1, suffix) + if(data1b ne null) new Vector1(data1b) + else super.appendedAll0(suffix, k) + } +} + + +/** 2-dimensional radix-balanced finger tree */ +private final class Vector2[+A](_prefix1: Arr1, private[immutable] val len1: Int, + private[immutable] val data2: Arr2, + _suffix1: Arr1, + _length0: Int) extends BigVector[A](_prefix1, _suffix1, _length0) { + + @inline private[this] def copy(prefix1: Arr1 = prefix1, len1: Int = len1, + data2: Arr2 = data2, + suffix1: Arr1 = suffix1, + length0: Int = length0) = + new Vector2(prefix1, len1, data2, suffix1, length0) + + @inline def apply(index: Int): A = { + if(index >= 0 && index < length0) { + val io = index - len1 + if(io >= 0) { + val i2 = io >>> BITS + val i1 = io & MASK + if(i2 < data2.length) data2(i2)(i1) + else suffix1(io & MASK) + } else prefix1(index) + }.asInstanceOf[A] else throw ioob(index) + } + + override def updated[B >: A](index: Int, elem: B): Vector[B] = { + if(index >= 0 && index < length0) { + if(index >= len1) { + val io = index - len1 + val i2 = io >>> BITS + val i1 = io & MASK + if(i2 < data2.length) copy(data2 = copyUpdate(data2, i2, i1, elem)) + else copy(suffix1 = copyUpdate(suffix1, i1, elem)) + } else { + copy(prefix1 = copyUpdate(prefix1, index, elem)) + } + } else throw ioob(index) + } + + override def appended[B >: A](elem: B): Vector[B] = { + if (suffix1.length < WIDTH ) copy(suffix1 = copyAppend1(suffix1, elem), length0 = length0+1) + else if(data2.length < WIDTH-2) copy(data2 = copyAppend(data2, suffix1), suffix1 = wrap1(elem), length0 = length0+1) + else new Vector3(prefix1, len1, data2, WIDTH*(WIDTH-2) + len1, empty3, wrap2(suffix1), wrap1(elem), length0+1) + } + + override def prepended[B >: A](elem: B): Vector[B] = { + if (len1 < WIDTH ) copy(copyPrepend1(elem, prefix1), len1+1, length0 = length0+1) + else if(data2.length < WIDTH-2) copy(wrap1(elem), 1, copyPrepend(prefix1, data2), length0 = length0+1) + else new Vector3(wrap1(elem), 1, wrap2(prefix1), len1+1, empty3, data2, suffix1, length0+1) + } + + override def map[B](f: A => B): Vector[B] = + copy(prefix1 = mapElems1(prefix1, f), data2 = mapElems(2, data2, f), suffix1 = mapElems1(suffix1, f)) + + protected[this] def slice0(lo: Int, hi: Int): Vector[A] = { + val b = new VectorSliceBuilder(lo, hi) + b.consider(1, prefix1) + b.consider(2, data2) + b.consider(1, suffix1) + b.result() + } + + override def tail: Vector[A] = + if(len1 > 1) copy(copyTail(prefix1), len1-1, length0 = length0-1) + else slice0(1, length0) + + override def init: Vector[A] = + if(suffix1.length > 1) copy(suffix1 = copyInit(suffix1), length0 = length0-1) + else slice0(0, length0-1) + + protected[immutable] def vectorSliceCount: Int = 3 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = (idx: @switch) match { + case 0 => prefix1 + case 1 => data2 + case 2 => suffix1 + } + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = (idx: @switch) match { + case 0 => len1 + case 1 => length0 - suffix1.length + case 2 => length0 + } + + override protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + prepend1IfSpace(prefix1, prefix) match { + case null => super.prependedAll0(prefix, k) + case prefix1b => + val diff = prefix1b.length - prefix1.length + copy(prefix1 = prefix1b, + len1 = len1 + diff, + length0 = length0 + diff, + ) + } + + override protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + val suffix1b = append1IfSpace(suffix1, suffix) + if(suffix1b ne null) copy(suffix1 = suffix1b, length0 = length0-suffix1.length+suffix1b.length) + else super.appendedAll0(suffix, k) + } +} + + +/** 3-dimensional radix-balanced finger tree */ +private final class Vector3[+A](_prefix1: Arr1, private[immutable] val len1: Int, + private[immutable] val prefix2: Arr2, private[immutable] val len12: Int, + private[immutable] val data3: Arr3, + private[immutable] val suffix2: Arr2, _suffix1: Arr1, + _length0: Int) extends BigVector[A](_prefix1, _suffix1, _length0) { + + @inline private[this] def copy(prefix1: Arr1 = prefix1, len1: Int = len1, + prefix2: Arr2 = prefix2, len12: Int = len12, + data3: Arr3 = data3, + suffix2: Arr2 = suffix2, suffix1: Arr1 = suffix1, + length0: Int = length0) = + new Vector3(prefix1, len1, prefix2, len12, data3, suffix2, suffix1, length0) + + @inline def apply(index: Int): A = { + if(index >= 0 && index < length0) { + val io = index - len12 + if(io >= 0) { + val i3 = io >>> BITS2 + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if(i3 < data3.length) data3(i3)(i2)(i1) + else if(i2 < suffix2.length) suffix2(i2)(i1) + else suffix1(i1) + } else if(index >= len1) { + val io = index - len1 + prefix2(io >>> BITS)(io & MASK) + } else prefix1(index) + }.asInstanceOf[A] else throw ioob(index) + } + + override def updated[B >: A](index: Int, elem: B): Vector[B] = { + if(index >= 0 && index < length0) { + if(index >= len12) { + val io = index - len12 + val i3 = io >>> BITS2 + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if (i3 < data3.length ) copy(data3 = copyUpdate(data3, i3, i2, i1, elem)) + else if(i2 < suffix2.length) copy(suffix2 = copyUpdate(suffix2, i2, i1, elem)) + else copy(suffix1 = copyUpdate(suffix1, i1, elem)) + } else if(index >= len1) { + val io = index - len1 + copy(prefix2 = copyUpdate(prefix2, io >>> BITS, io & MASK, elem)) + } else { + copy(prefix1 = copyUpdate(prefix1, index, elem)) + } + } else throw ioob(index) + } + + override def appended[B >: A](elem: B): Vector[B] = { + if (suffix1.length < WIDTH ) copy(suffix1 = copyAppend1(suffix1, elem), length0 = length0+1) + else if(suffix2.length < WIDTH-1) copy(suffix2 = copyAppend(suffix2, suffix1), suffix1 = wrap1(elem), length0 = length0+1) + else if(data3.length < WIDTH-2) copy(data3 = copyAppend(data3, copyAppend(suffix2, suffix1)), suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else new Vector4(prefix1, len1, prefix2, len12, data3, (WIDTH-2)*WIDTH2 + len12, empty4, wrap3(copyAppend(suffix2, suffix1)), empty2, wrap1(elem), length0+1) + } + + override def prepended[B >: A](elem: B): Vector[B] = { + if (len1 < WIDTH ) copy(prefix1 = copyPrepend1(elem, prefix1), len1 = len1+1, len12 = len12+1, length0 = length0+1) + else if(len12 < WIDTH2 ) copy(prefix1 = wrap1(elem), len1 = 1, prefix2 = copyPrepend(prefix1, prefix2), len12 = len12+1, length0 = length0+1) + else if(data3.length < WIDTH-2) copy(prefix1 = wrap1(elem), len1 = 1, prefix2 = empty2, len12 = 1, data3 = copyPrepend(copyPrepend(prefix1, prefix2), data3), length0 = length0+1) + else new Vector4(wrap1(elem), 1, empty2, 1, wrap3(copyPrepend(prefix1, prefix2)), len12+1, empty4, data3, suffix2, suffix1, length0+1) + } + + override def map[B](f: A => B): Vector[B] = + copy(prefix1 = mapElems1(prefix1, f), prefix2 = mapElems(2, prefix2, f), + data3 = mapElems(3, data3, f), + suffix2 = mapElems(2, suffix2, f), suffix1 = mapElems1(suffix1, f)) + + protected[this] def slice0(lo: Int, hi: Int): Vector[A] = { + val b = new VectorSliceBuilder(lo, hi) + b.consider(1, prefix1) + b.consider(2, prefix2) + b.consider(3, data3) + b.consider(2, suffix2) + b.consider(1, suffix1) + b.result() + } + + override def tail: Vector[A] = + if(len1 > 1) copy(prefix1 = copyTail(prefix1), len1 = len1-1, len12 = len12-1, length0 = length0-1) + else slice0(1, length0) + + override def init: Vector[A] = + if(suffix1.length > 1) copy(suffix1 = copyInit(suffix1), length0 = length0-1) + else slice0(0, length0-1) + + protected[immutable] def vectorSliceCount: Int = 5 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = (idx: @switch) match { + case 0 => prefix1 + case 1 => prefix2 + case 2 => data3 + case 3 => suffix2 + case 4 => suffix1 + } + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = (idx: @switch) match { + case 0 => len1 + case 1 => len12 + case 2 => len12 + data3.length*WIDTH2 + case 3 => length0 - suffix1.length + case 4 => length0 + } + + override protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + prepend1IfSpace(prefix1, prefix) match { + case null => super.prependedAll0(prefix, k) + case prefix1b => + val diff = prefix1b.length - prefix1.length + copy(prefix1 = prefix1b, + len1 = len1 + diff, + len12 = len12 + diff, + length0 = length0 + diff, + ) + } + + override protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + val suffix1b = append1IfSpace(suffix1, suffix) + if(suffix1b ne null) copy(suffix1 = suffix1b, length0 = length0-suffix1.length+suffix1b.length) + else super.appendedAll0(suffix, k) + } +} + + +/** 4-dimensional radix-balanced finger tree */ +private final class Vector4[+A](_prefix1: Arr1, private[immutable] val len1: Int, + private[immutable] val prefix2: Arr2, private[immutable] val len12: Int, + private[immutable] val prefix3: Arr3, private[immutable] val len123: Int, + private[immutable] val data4: Arr4, + private[immutable] val suffix3: Arr3, private[immutable] val suffix2: Arr2, _suffix1: Arr1, + _length0: Int) extends BigVector[A](_prefix1, _suffix1, _length0) { + + @inline private[this] def copy(prefix1: Arr1 = prefix1, len1: Int = len1, + prefix2: Arr2 = prefix2, len12: Int = len12, + prefix3: Arr3 = prefix3, len123: Int = len123, + data4: Arr4 = data4, + suffix3: Arr3 = suffix3, suffix2: Arr2 = suffix2, suffix1: Arr1 = suffix1, + length0: Int = length0) = + new Vector4(prefix1, len1, prefix2, len12, prefix3, len123, data4, suffix3, suffix2, suffix1, length0) + + @inline def apply(index: Int): A = { + if(index >= 0 && index < length0) { + val io = index - len123 + if(io >= 0) { + val i4 = io >>> BITS3 + val i3 = (io >>> BITS2) & MASK + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if(i4 < data4.length) data4(i4)(i3)(i2)(i1) + else if(i3 < suffix3.length) suffix3(i3)(i2)(i1) + else if(i2 < suffix2.length) suffix2(i2)(i1) + else suffix1(i1) + } else if(index >= len12) { + val io = index - len12 + prefix3(io >>> BITS2)((io >>> BITS) & MASK)(io & MASK) + } else if(index >= len1) { + val io = index - len1 + prefix2(io >>> BITS)(io & MASK) + } else prefix1(index) + }.asInstanceOf[A] else throw ioob(index) + } + + override def updated[B >: A](index: Int, elem: B): Vector[B] = { + if(index >= 0 && index < length0) { + if(index >= len123) { + val io = index - len123 + val i4 = io >>> BITS3 + val i3 = (io >>> BITS2) & MASK + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if (i4 < data4.length ) copy(data4 = copyUpdate(data4, i4, i3, i2, i1, elem)) + else if(i3 < suffix3.length) copy(suffix3 = copyUpdate(suffix3, i3, i2, i1, elem)) + else if(i2 < suffix2.length) copy(suffix2 = copyUpdate(suffix2, i2, i1, elem)) + else copy(suffix1 = copyUpdate(suffix1, i1, elem)) + } else if(index >= len12) { + val io = index - len12 + copy(prefix3 = copyUpdate(prefix3, io >>> BITS2, (io >>> BITS) & MASK, io & MASK, elem)) + } else if(index >= len1) { + val io = index - len1 + copy(prefix2 = copyUpdate(prefix2, io >>> BITS, io & MASK, elem)) + } else { + copy(prefix1 = copyUpdate(prefix1, index, elem)) + } + } else throw ioob(index) + } + + override def appended[B >: A](elem: B): Vector[B] = { + if (suffix1.length < WIDTH ) copy(suffix1 = copyAppend1(suffix1, elem), length0 = length0+1) + else if(suffix2.length < WIDTH-1) copy(suffix2 = copyAppend(suffix2, suffix1), suffix1 = wrap1(elem), length0 = length0+1) + else if(suffix3.length < WIDTH-1) copy(suffix3 = copyAppend(suffix3, copyAppend(suffix2, suffix1)), suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else if(data4.length < WIDTH-2) copy(data4 = copyAppend(data4, copyAppend(suffix3, copyAppend(suffix2, suffix1))), suffix3 = empty3, suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else new Vector5(prefix1, len1, prefix2, len12, prefix3, len123, data4, (WIDTH-2)*WIDTH3 + len123, empty5, wrap4(copyAppend(suffix3, copyAppend(suffix2, suffix1))), empty3, empty2, wrap1(elem), length0+1) + } + + override def prepended[B >: A](elem: B): Vector[B] = { + if (len1 < WIDTH ) copy(copyPrepend1(elem, prefix1), len1+1, len12 = len12+1, len123 = len123+1, length0 = length0+1) + else if(len12 < WIDTH2 ) copy(wrap1(elem), 1, copyPrepend(prefix1, prefix2), len12+1, len123 = len123+1, length0 = length0+1) + else if(len123 < WIDTH3 ) copy(wrap1(elem), 1, empty2, 1, copyPrepend(copyPrepend(prefix1, prefix2), prefix3), len123+1, length0 = length0+1) + else if(data4.length < WIDTH-2) copy(wrap1(elem), 1, empty2, 1, empty3, 1, copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), data4), length0 = length0+1) + else new Vector5(wrap1(elem), 1, empty2, 1, empty3, 1, wrap4(copyPrepend(copyPrepend(prefix1, prefix2), prefix3)), len123+1, empty5, data4, suffix3, suffix2, suffix1, length0+1) + } + + override def map[B](f: A => B): Vector[B] = + copy(prefix1 = mapElems1(prefix1, f), prefix2 = mapElems(2, prefix2, f), prefix3 = mapElems(3, prefix3, f), + data4 = mapElems(4, data4, f), + suffix3 = mapElems(3, suffix3, f), suffix2 = mapElems(2, suffix2, f), suffix1 = mapElems1(suffix1, f)) + + protected[this] def slice0(lo: Int, hi: Int): Vector[A] = { + val b = new VectorSliceBuilder(lo, hi) + b.consider(1, prefix1) + b.consider(2, prefix2) + b.consider(3, prefix3) + b.consider(4, data4) + b.consider(3, suffix3) + b.consider(2, suffix2) + b.consider(1, suffix1) + b.result() + } + + override def tail: Vector[A] = + if(len1 > 1) copy(copyTail(prefix1), len1-1, len12 = len12-1, len123 = len123-1, length0 = length0-1) + else slice0(1, length0) + + override def init: Vector[A] = + if(suffix1.length > 1) copy(suffix1 = copyInit(suffix1), length0 = length0-1) + else slice0(0, length0-1) + + protected[immutable] def vectorSliceCount: Int = 7 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = (idx: @switch) match { + case 0 => prefix1 + case 1 => prefix2 + case 2 => prefix3 + case 3 => data4 + case 4 => suffix3 + case 5 => suffix2 + case 6 => suffix1 + } + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = (idx: @switch) match { + case 0 => len1 + case 1 => len12 + case 2 => len123 + case 3 => len123 + data4.length*WIDTH3 + case 4 => len123 + data4.length*WIDTH3 + suffix3.length*WIDTH2 + case 5 => length0 - suffix1.length + case 6 => length0 + } + + override protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + prepend1IfSpace(prefix1, prefix) match { + case null => super.prependedAll0(prefix, k) + case prefix1b => + val diff = prefix1b.length - prefix1.length + copy(prefix1 = prefix1b, + len1 = len1 + diff, + len12 = len12 + diff, + len123 = len123 + diff, + length0 = length0 + diff, + ) + } + + override protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + val suffix1b = append1IfSpace(suffix1, suffix) + if(suffix1b ne null) copy(suffix1 = suffix1b, length0 = length0-suffix1.length+suffix1b.length) + else super.appendedAll0(suffix, k) + } +} + + +/** 5-dimensional radix-balanced finger tree */ +private final class Vector5[+A](_prefix1: Arr1, private[immutable] val len1: Int, + private[immutable] val prefix2: Arr2, private[immutable] val len12: Int, + private[immutable] val prefix3: Arr3, private[immutable] val len123: Int, + private[immutable] val prefix4: Arr4, private[immutable] val len1234: Int, + private[immutable] val data5: Arr5, + private[immutable] val suffix4: Arr4, private[immutable] val suffix3: Arr3, private[immutable] val suffix2: Arr2, _suffix1: Arr1, + _length0: Int) extends BigVector[A](_prefix1, _suffix1, _length0) { + + @inline private[this] def copy(prefix1: Arr1 = prefix1, len1: Int = len1, + prefix2: Arr2 = prefix2, len12: Int = len12, + prefix3: Arr3 = prefix3, len123: Int = len123, + prefix4: Arr4 = prefix4, len1234: Int = len1234, + data5: Arr5 = data5, + suffix4: Arr4 = suffix4, suffix3: Arr3 = suffix3, suffix2: Arr2 = suffix2, suffix1: Arr1 = suffix1, + length0: Int = length0) = + new Vector5(prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, data5, suffix4, suffix3, suffix2, suffix1, length0) + + @inline def apply(index: Int): A = { + if(index >= 0 && index < length0) { + val io = index - len1234 + if(io >= 0) { + val i5 = io >>> BITS4 + val i4 = (io >>> BITS3) & MASK + val i3 = (io >>> BITS2) & MASK + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if(i5 < data5.length) data5(i5)(i4)(i3)(i2)(i1) + else if(i4 < suffix4.length) suffix4(i4)(i3)(i2)(i1) + else if(i3 < suffix3.length) suffix3(i3)(i2)(i1) + else if(i2 < suffix2.length) suffix2(i2)(i1) + else suffix1(i1) + } else if(index >= len123) { + val io = index - len123 + prefix4(io >>> BITS3)((io >>> BITS2) & MASK)((io >>> BITS) & MASK)(io & MASK) + } else if(index >= len12) { + val io = index - len12 + prefix3(io >>> BITS2)((io >>> BITS) & MASK)(io & MASK) + } else if(index >= len1) { + val io = index - len1 + prefix2(io >>> BITS)(io & MASK) + } else prefix1(index) + }.asInstanceOf[A] else throw ioob(index) + } + + override def updated[B >: A](index: Int, elem: B): Vector[B] = { + if(index >= 0 && index < length0) { + if(index >= len1234) { + val io = index - len1234 + val i5 = io >>> BITS4 + val i4 = (io >>> BITS3) & MASK + val i3 = (io >>> BITS2) & MASK + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if (i5 < data5.length ) copy(data5 = copyUpdate(data5, i5, i4, i3, i2, i1, elem)) + else if(i4 < suffix4.length) copy(suffix4 = copyUpdate(suffix4, i4, i3, i2, i1, elem)) + else if(i3 < suffix3.length) copy(suffix3 = copyUpdate(suffix3, i3, i2, i1, elem)) + else if(i2 < suffix2.length) copy(suffix2 = copyUpdate(suffix2, i2, i1, elem)) + else copy(suffix1 = copyUpdate(suffix1, i1, elem)) + } else if(index >= len123) { + val io = index - len123 + copy(prefix4 = copyUpdate(prefix4, io >>> BITS3, (io >>> BITS2) & MASK, (io >>> BITS) & MASK, io & MASK, elem)) + } else if(index >= len12) { + val io = index - len12 + copy(prefix3 = copyUpdate(prefix3, io >>> BITS2, (io >>> BITS) & MASK, io & MASK, elem)) + } else if(index >= len1) { + val io = index - len1 + copy(prefix2 = copyUpdate(prefix2, io >>> BITS, io & MASK, elem)) + } else { + copy(prefix1 = copyUpdate(prefix1, index, elem)) + } + } else throw ioob(index) + } + + override def appended[B >: A](elem: B): Vector[B] = { + if (suffix1.length < WIDTH ) copy(suffix1 = copyAppend1(suffix1, elem), length0 = length0+1) + else if(suffix2.length < WIDTH-1) copy(suffix2 = copyAppend(suffix2, suffix1), suffix1 = wrap1(elem), length0 = length0+1) + else if(suffix3.length < WIDTH-1) copy(suffix3 = copyAppend(suffix3, copyAppend(suffix2, suffix1)), suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else if(suffix4.length < WIDTH-1) copy(suffix4 = copyAppend(suffix4, copyAppend(suffix3, copyAppend(suffix2, suffix1))), suffix3 = empty3, suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else if(data5.length < WIDTH-2) copy(data5 = copyAppend(data5, copyAppend(suffix4, copyAppend(suffix3, copyAppend(suffix2, suffix1)))), suffix4 = empty4, suffix3 = empty3, suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else new Vector6(prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, data5, (WIDTH-2)*WIDTH4 + len1234, empty6, wrap5(copyAppend(suffix4, copyAppend(suffix3, copyAppend(suffix2, suffix1)))), empty4, empty3, empty2, wrap1(elem), length0+1) + } + + override def prepended[B >: A](elem: B): Vector[B] = { + if (len1 < WIDTH ) copy(copyPrepend1(elem, prefix1), len1+1, len12 = len12+1, len123 = len123+1, len1234 = len1234+1, length0 = length0+1) + else if(len12 < WIDTH2 ) copy(wrap1(elem), 1, copyPrepend(prefix1, prefix2), len12+1, len123 = len123+1, len1234 = len1234+1, length0 = length0+1) + else if(len123 < WIDTH3 ) copy(wrap1(elem), 1, empty2, 1, copyPrepend(copyPrepend(prefix1, prefix2), prefix3), len123+1, len1234 = len1234+1, length0 = length0+1) + else if(len1234 < WIDTH4 ) copy(wrap1(elem), 1, empty2, 1, empty3, 1, copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), prefix4), len1234+1, length0 = length0+1) + else if(data5.length < WIDTH-2) copy(wrap1(elem), 1, empty2, 1, empty3, 1, empty4, 1, copyPrepend(copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), prefix4), data5), length0 = length0+1) + else new Vector6(wrap1(elem), 1, empty2, 1, empty3, 1, empty4, 1, wrap5(copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), prefix4)), len1234+1, empty6, data5, suffix4, suffix3, suffix2, suffix1, length0+1) + } + + override def map[B](f: A => B): Vector[B] = + copy(prefix1 = mapElems1(prefix1, f), prefix2 = mapElems(2, prefix2, f), prefix3 = mapElems(3, prefix3, f), prefix4 = mapElems(4, prefix4, f), + data5 = mapElems(5, data5, f), + suffix4 = mapElems(4, suffix4, f), suffix3 = mapElems(3, suffix3, f), suffix2 = mapElems(2, suffix2, f), suffix1 = mapElems1(suffix1, f)) + + protected[this] def slice0(lo: Int, hi: Int): Vector[A] = { + val b = new VectorSliceBuilder(lo, hi) + b.consider(1, prefix1) + b.consider(2, prefix2) + b.consider(3, prefix3) + b.consider(4, prefix4) + b.consider(5, data5) + b.consider(4, suffix4) + b.consider(3, suffix3) + b.consider(2, suffix2) + b.consider(1, suffix1) + b.result() + } + + override def tail: Vector[A] = + if(len1 > 1) copy(copyTail(prefix1), len1-1, len12 = len12-1, len123 = len123-1, len1234 = len1234-1, length0 = length0-1) + else slice0(1, length0) + + override def init: Vector[A] = + if(suffix1.length > 1) copy(suffix1 = copyInit(suffix1), length0 = length0-1) + else slice0(0, length0-1) + + protected[immutable] def vectorSliceCount: Int = 9 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = (idx: @switch) match { + case 0 => prefix1 + case 1 => prefix2 + case 2 => prefix3 + case 3 => prefix4 + case 4 => data5 + case 5 => suffix4 + case 6 => suffix3 + case 7 => suffix2 + case 8 => suffix1 + } + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = (idx: @switch) match { + case 0 => len1 + case 1 => len12 + case 2 => len123 + case 3 => len1234 + case 4 => len1234 + data5.length*WIDTH4 + case 5 => len1234 + data5.length*WIDTH4 + suffix4.length*WIDTH3 + case 6 => len1234 + data5.length*WIDTH4 + suffix4.length*WIDTH3 + suffix3.length*WIDTH2 + case 7 => length0 - suffix1.length + case 8 => length0 + } + + override protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + prepend1IfSpace(prefix1, prefix) match { + case null => super.prependedAll0(prefix, k) + case prefix1b => + val diff = prefix1b.length - prefix1.length + copy(prefix1 = prefix1b, + len1 = len1 + diff, + len12 = len12 + diff, + len123 = len123 + diff, + len1234 = len1234 + diff, + length0 = length0 + diff, + ) + } + + override protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + val suffix1b = append1IfSpace(suffix1, suffix) + if(suffix1b ne null) copy(suffix1 = suffix1b, length0 = length0-suffix1.length+suffix1b.length) + else super.appendedAll0(suffix, k) + } +} + + +/** 6-dimensional radix-balanced finger tree */ +private final class Vector6[+A](_prefix1: Arr1, private[immutable] val len1: Int, + private[immutable] val prefix2: Arr2, private[immutable] val len12: Int, + private[immutable] val prefix3: Arr3, private[immutable] val len123: Int, + private[immutable] val prefix4: Arr4, private[immutable] val len1234: Int, + private[immutable] val prefix5: Arr5, private[immutable] val len12345: Int, + private[immutable] val data6: Arr6, + private[immutable] val suffix5: Arr5, private[immutable] val suffix4: Arr4, private[immutable] val suffix3: Arr3, private[immutable] val suffix2: Arr2, _suffix1: Arr1, + _length0: Int) extends BigVector[A](_prefix1, _suffix1, _length0) { + + @inline private[this] def copy(prefix1: Arr1 = prefix1, len1: Int = len1, + prefix2: Arr2 = prefix2, len12: Int = len12, + prefix3: Arr3 = prefix3, len123: Int = len123, + prefix4: Arr4 = prefix4, len1234: Int = len1234, + prefix5: Arr5 = prefix5, len12345: Int = len12345, + data6: Arr6 = data6, + suffix5: Arr5 = suffix5, suffix4: Arr4 = suffix4, suffix3: Arr3 = suffix3, suffix2: Arr2 = suffix2, suffix1: Arr1 = suffix1, + length0: Int = length0) = + new Vector6(prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, prefix5, len12345, data6, suffix5, suffix4, suffix3, suffix2, suffix1, length0) + + @inline def apply(index: Int): A = { + if(index >= 0 && index < length0) { + val io = index - len12345 + if(io >= 0) { + val i6 = io >>> BITS5 + val i5 = (io >>> BITS4) & MASK + val i4 = (io >>> BITS3) & MASK + val i3 = (io >>> BITS2) & MASK + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if(i6 < data6.length) data6(i6)(i5)(i4)(i3)(i2)(i1) + else if(i5 < suffix5.length) suffix5(i5)(i4)(i3)(i2)(i1) + else if(i4 < suffix4.length) suffix4(i4)(i3)(i2)(i1) + else if(i3 < suffix3.length) suffix3(i3)(i2)(i1) + else if(i2 < suffix2.length) suffix2(i2)(i1) + else suffix1(i1) + } else if(index >= len1234) { + val io = index - len1234 + prefix5(io >>> BITS4)((io >>> BITS3) & MASK)((io >>> BITS2) & MASK)((io >>> BITS) & MASK)(io & MASK) + } else if(index >= len123) { + val io = index - len123 + prefix4(io >>> BITS3)((io >>> BITS2) & MASK)((io >>> BITS) & MASK)(io & MASK) + } else if(index >= len12) { + val io = index - len12 + prefix3(io >>> BITS2)((io >>> BITS) & MASK)(io & MASK) + } else if(index >= len1) { + val io = index - len1 + prefix2(io >>> BITS)(io & MASK) + } else prefix1(index) + }.asInstanceOf[A] else throw ioob(index) + } + + override def updated[B >: A](index: Int, elem: B): Vector[B] = { + if(index >= 0 && index < length0) { + if(index >= len12345) { + val io = index - len12345 + val i6 = io >>> BITS5 + val i5 = (io >>> BITS4) & MASK + val i4 = (io >>> BITS3) & MASK + val i3 = (io >>> BITS2) & MASK + val i2 = (io >>> BITS) & MASK + val i1 = io & MASK + if (i6 < data6.length ) copy(data6 = copyUpdate(data6, i6, i5, i4, i3, i2, i1, elem)) + else if(i5 < suffix5.length) copy(suffix5 = copyUpdate(suffix5, i5, i4, i3, i2, i1, elem)) + else if(i4 < suffix4.length) copy(suffix4 = copyUpdate(suffix4, i4, i3, i2, i1, elem)) + else if(i3 < suffix3.length) copy(suffix3 = copyUpdate(suffix3, i3, i2, i1, elem)) + else if(i2 < suffix2.length) copy(suffix2 = copyUpdate(suffix2, i2, i1, elem)) + else copy(suffix1 = copyUpdate(suffix1, i1, elem)) + } else if(index >= len1234) { + val io = index - len1234 + copy(prefix5 = copyUpdate(prefix5, io >>> BITS4, (io >>> BITS3) & MASK, (io >>> BITS2) & MASK, (io >>> BITS) & MASK, io & MASK, elem)) + } else if(index >= len123) { + val io = index - len123 + copy(prefix4 = copyUpdate(prefix4, io >>> BITS3, (io >>> BITS2) & MASK, (io >>> BITS) & MASK, io & MASK, elem)) + } else if(index >= len12) { + val io = index - len12 + copy(prefix3 = copyUpdate(prefix3, io >>> BITS2, (io >>> BITS) & MASK, io & MASK, elem)) + } else if(index >= len1) { + val io = index - len1 + copy(prefix2 = copyUpdate(prefix2, io >>> BITS, io & MASK, elem)) + } else { + copy(prefix1 = copyUpdate(prefix1, index, elem)) + } + } else throw ioob(index) + } + + override def appended[B >: A](elem: B): Vector[B] = { + if (suffix1.length < WIDTH ) copy(suffix1 = copyAppend1(suffix1, elem), length0 = length0+1) + else if(suffix2.length < WIDTH-1 ) copy(suffix2 = copyAppend(suffix2, suffix1), suffix1 = wrap1(elem), length0 = length0+1) + else if(suffix3.length < WIDTH-1 ) copy(suffix3 = copyAppend(suffix3, copyAppend(suffix2, suffix1)), suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else if(suffix4.length < WIDTH-1 ) copy(suffix4 = copyAppend(suffix4, copyAppend(suffix3, copyAppend(suffix2, suffix1))), suffix3 = empty3, suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else if(suffix5.length < WIDTH-1 ) copy(suffix5 = copyAppend(suffix5, copyAppend(suffix4, copyAppend(suffix3, copyAppend(suffix2, suffix1)))), suffix4 = empty4, suffix3 = empty3, suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else if(data6.length < LASTWIDTH-2) copy(data6 = copyAppend(data6, copyAppend(suffix5, copyAppend(suffix4, copyAppend(suffix3, copyAppend(suffix2, suffix1))))), suffix5 = empty5, suffix4 = empty4, suffix3 = empty3, suffix2 = empty2, suffix1 = wrap1(elem), length0 = length0+1) + else throw new IllegalArgumentException + } + + override def prepended[B >: A](elem: B): Vector[B] = { + if (len1 < WIDTH ) copy(copyPrepend1(elem, prefix1), len1+1, len12 = len12+1, len123 = len123+1, len1234 = len1234+1, len12345 = len12345+1, length0 = length0+1) + else if(len12 < WIDTH2 ) copy(wrap1(elem), 1, copyPrepend(prefix1, prefix2), len12+1, len123 = len123+1, len1234 = len1234+1, len12345 = len12345+1, length0 = length0+1) + else if(len123 < WIDTH3 ) copy(wrap1(elem), 1, empty2, 1, copyPrepend(copyPrepend(prefix1, prefix2), prefix3), len123+1, len1234 = len1234+1, len12345 = len12345+1, length0 = length0+1) + else if(len1234 < WIDTH4 ) copy(wrap1(elem), 1, empty2, 1, empty3, 1, copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), prefix4), len1234+1, len12345 = len12345+1, length0 = length0+1) + else if(len12345 < WIDTH5 ) copy(wrap1(elem), 1, empty2, 1, empty3, 1, empty4, 1, copyPrepend(copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), prefix4), prefix5), len12345+1, length0 = length0+1) + else if(data6.length < LASTWIDTH-2) copy(wrap1(elem), 1, empty2, 1, empty3, 1, empty4, 1, empty5, 1, copyPrepend(copyPrepend(copyPrepend(copyPrepend(copyPrepend(prefix1, prefix2), prefix3), prefix4), prefix5), data6), length0 = length0+1) + else throw new IllegalArgumentException + } + + override def map[B](f: A => B): Vector[B] = + copy(prefix1 = mapElems1(prefix1, f), prefix2 = mapElems(2, prefix2, f), prefix3 = mapElems(3, prefix3, f), prefix4 = mapElems(4, prefix4, f), prefix5 = mapElems(5, prefix5, f), + data6 = mapElems(6, data6, f), + suffix5 = mapElems(5, suffix5, f), suffix4 = mapElems(4, suffix4, f), suffix3 = mapElems(3, suffix3, f), suffix2 = mapElems(2, suffix2, f), suffix1 = mapElems1(suffix1, f)) + + protected[this] def slice0(lo: Int, hi: Int): Vector[A] = { + val b = new VectorSliceBuilder(lo, hi) + b.consider(1, prefix1) + b.consider(2, prefix2) + b.consider(3, prefix3) + b.consider(4, prefix4) + b.consider(5, prefix5) + b.consider(6, data6) + b.consider(5, suffix5) + b.consider(4, suffix4) + b.consider(3, suffix3) + b.consider(2, suffix2) + b.consider(1, suffix1) + b.result() + } + + override def tail: Vector[A] = + if(len1 > 1) copy(copyTail(prefix1), len1-1, len12 = len12-1, len123 = len123-1, len1234 = len1234-1, len12345 = len12345-1, length0 = length0-1) + else slice0(1, length0) + + override def init: Vector[A] = + if(suffix1.length > 1) copy(suffix1 = copyInit(suffix1), length0 = length0-1) + else slice0(0, length0-1) + + protected[immutable] def vectorSliceCount: Int = 11 + protected[immutable] def vectorSlice(idx: Int): Array[_ <: AnyRef] = (idx: @switch) match { + case 0 => prefix1 + case 1 => prefix2 + case 2 => prefix3 + case 3 => prefix4 + case 4 => prefix5 + case 5 => data6 + case 6 => suffix5 + case 7 => suffix4 + case 8 => suffix3 + case 9 => suffix2 + case 10 => suffix1 + } + protected[immutable] def vectorSlicePrefixLength(idx: Int): Int = (idx: @switch) match { + case 0 => len1 + case 1 => len12 + case 2 => len123 + case 3 => len1234 + case 4 => len12345 + case 5 => len12345 + data6.length*WIDTH5 + case 6 => len12345 + data6.length*WIDTH5 + suffix5.length*WIDTH4 + case 7 => len12345 + data6.length*WIDTH5 + suffix5.length*WIDTH4 + suffix4.length*WIDTH3 + case 8 => len12345 + data6.length*WIDTH5 + suffix5.length*WIDTH4 + suffix4.length*WIDTH3 + suffix3.length*WIDTH2 + case 9 => length0 - suffix1.length + case 10 => length0 + } + + override protected[this] def prependedAll0[B >: A](prefix: collection.IterableOnce[B]^, k: Int): Vector[B] = + prepend1IfSpace(prefix1, prefix) match { + case null => super.prependedAll0(prefix, k) + case prefix1b => + val diff = prefix1b.length - prefix1.length + copy(prefix1 = prefix1b, + len1 = len1 + diff, + len12 = len12 + diff, + len123 = len123 + diff, + len1234 = len1234 + diff, + len12345 = len12345 + diff, + length0 = length0 + diff, + ) + } + + override protected[this] def appendedAll0[B >: A](suffix: collection.IterableOnce[B]^, k: Int): Vector[B] = { + val suffix1b = append1IfSpace(suffix1, suffix) + if(suffix1b ne null) copy(suffix1 = suffix1b, length0 = length0-suffix1.length+suffix1b.length) + else super.appendedAll0(suffix, k) + } +} + + +/** Helper class for vector slicing. It is initialized with the validated start and end index, + * then the vector slices are added in succession with `consider`. No matter what the dimension + * of the originating vector is or where the cut is performed, this always results in a + * structure with the highest-dimensional data in the middle and fingers of decreasing dimension + * at both ends, which can be turned into a new vector with very little rebalancing. + */ +private final class VectorSliceBuilder(lo: Int, hi: Int) { + //println(s"***** VectorSliceBuilder($lo, $hi)") + + private[this] val slices = new Array[Array[AnyRef]](11) + private[this] var len, pos, maxDim = 0 + + @inline private[this] def prefixIdx(n: Int) = n-1 + @inline private[this] def suffixIdx(n: Int) = 11-n + + def consider[T <: AnyRef](n: Int, a: Array[T]): Unit = { + //println(s"***** consider($n, /${a.length})") + val count = a.length * (1 << (BITS*(n-1))) + val lo0 = mmax(lo-pos, 0) + val hi0 = mmin(hi-pos, count) + if(hi0 > lo0) { + addSlice(n, a, lo0, hi0) + len += (hi0 - lo0) + } + pos += count + } + + private[this] def addSlice[T <: AnyRef](n: Int, a: Array[T], lo: Int, hi: Int): Unit = { + //println(s"***** addSlice($n, /${a.length}, $lo, $hi)") + if(n == 1) { + add(1, copyOrUse(a, lo, hi)) + } else { + val bitsN = BITS * (n-1) + val widthN = 1 << bitsN + val loN = lo >>> bitsN + val hiN = hi >>> bitsN + val loRest = lo & (widthN - 1) + val hiRest = hi & (widthN - 1) + //println(s"***** bitsN=$bitsN, loN=$loN, hiN=$hiN, loRest=$loRest, hiRest=$hiRest") + if(loRest == 0) { + if(hiRest == 0) { + add(n, copyOrUse(a, loN, hiN)) + } else { + if(hiN > loN) add(n, copyOrUse(a, loN, hiN)) + addSlice(n-1, a(hiN).asInstanceOf[Array[AnyRef]], 0, hiRest) + } + } else { + if(hiN == loN) { + addSlice(n-1, a(loN).asInstanceOf[Array[AnyRef]], loRest, hiRest) + } else { + addSlice(n-1, a(loN).asInstanceOf[Array[AnyRef]], loRest, widthN) + if(hiRest == 0) { + if(hiN > loN+1) add(n, copyOrUse(a, loN+1, hiN)) + } else { + if(hiN > loN+1) add(n, copyOrUse(a, loN+1, hiN)) + addSlice(n-1, a(hiN).asInstanceOf[Array[AnyRef]], 0, hiRest) + } + } + } + } + } + + private[this] def add[T <: AnyRef](n: Int, a: Array[T]): Unit = { + //println(s"***** add($n, /${a.length})") + val idx = + if(n <= maxDim) suffixIdx(n) + else { maxDim = n; prefixIdx(n) } + slices(idx) = a.asInstanceOf[Array[AnyRef]] + } + + def result[A](): Vector[A] = { + //println(s"***** result: $len, $maxDim") + if(len <= 32) { + if(len == 0) Vector0 + else { + val prefix1 = slices(prefixIdx(1)) + val suffix1 = slices(suffixIdx(1)) + //println(s"***** prefix1: ${if(prefix1 == null) "null" else prefix1.mkString("[", ",", "]")}, suffix1: ${if(suffix1 == null) "null" else suffix1.mkString("[", ",", "]")}") + val a: Arr1 = + if(prefix1 ne null) { + if(suffix1 ne null) concatArrays(prefix1, suffix1) + else prefix1 + } else if(suffix1 ne null) suffix1 + else { + val prefix2 = slices(prefixIdx(2)).asInstanceOf[Arr2] + if(prefix2 ne null) prefix2(0) + else { + val suffix2 = slices(suffixIdx(2)).asInstanceOf[Arr2] + suffix2(0) + } + } + new Vector1(a) + } + } else { + balancePrefix(1) + balanceSuffix(1) + var resultDim = maxDim + if(resultDim < 6) { + val pre = slices(prefixIdx(maxDim)) + val suf = slices(suffixIdx(maxDim)) + if((pre ne null) && (suf ne null)) { + // The highest-dimensional data consists of two slices: concatenate if they fit into the main data array, + // otherwise increase the dimension + if(pre.length + suf.length <= WIDTH-2) { + slices(prefixIdx(maxDim)) = concatArrays(pre, suf) + slices(suffixIdx(maxDim)) = null + } else resultDim += 1 + } else { + // A single highest-dimensional slice could have length WIDTH-1 if it came from a prefix or suffix but we + // only allow WIDTH-2 for the main data, so increase the dimension in this case + val one = if(pre ne null) pre else suf + if(one.length > WIDTH-2) resultDim += 1 + } + } + val prefix1 = slices(prefixIdx(1)) + val suffix1 = slices(suffixIdx(1)) + val len1 = prefix1.length + val res = (resultDim: @switch) match { + case 2 => + val data2 = dataOr(2, empty2) + new Vector2[A](prefix1, len1, data2, suffix1, len) + case 3 => + val prefix2 = prefixOr(2, empty2) + val data3 = dataOr(3, empty3) + val suffix2 = suffixOr(2, empty2) + val len12 = len1 + (prefix2.length * WIDTH) + new Vector3[A](prefix1, len1, prefix2, len12, data3, suffix2, suffix1, len) + case 4 => + val prefix2 = prefixOr(2, empty2) + val prefix3 = prefixOr(3, empty3) + val data4 = dataOr(4, empty4) + val suffix3 = suffixOr(3, empty3) + val suffix2 = suffixOr(2, empty2) + val len12 = len1 + (prefix2.length * WIDTH) + val len123 = len12 + (prefix3.length * WIDTH2) + new Vector4[A](prefix1, len1, prefix2, len12, prefix3, len123, data4, suffix3, suffix2, suffix1, len) + case 5 => + val prefix2 = prefixOr(2, empty2) + val prefix3 = prefixOr(3, empty3) + val prefix4 = prefixOr(4, empty4) + val data5 = dataOr(5, empty5) + val suffix4 = suffixOr(4, empty4) + val suffix3 = suffixOr(3, empty3) + val suffix2 = suffixOr(2, empty2) + val len12 = len1 + (prefix2.length * WIDTH) + val len123 = len12 + (prefix3.length * WIDTH2) + val len1234 = len123 + (prefix4.length * WIDTH3) + new Vector5[A](prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, data5, suffix4, suffix3, suffix2, suffix1, len) + case 6 => + val prefix2 = prefixOr(2, empty2) + val prefix3 = prefixOr(3, empty3) + val prefix4 = prefixOr(4, empty4) + val prefix5 = prefixOr(5, empty5) + val data6 = dataOr(6, empty6) + val suffix5 = suffixOr(5, empty5) + val suffix4 = suffixOr(4, empty4) + val suffix3 = suffixOr(3, empty3) + val suffix2 = suffixOr(2, empty2) + val len12 = len1 + (prefix2.length * WIDTH) + val len123 = len12 + (prefix3.length * WIDTH2) + val len1234 = len123 + (prefix4.length * WIDTH3) + val len12345 = len1234 + (prefix5.length * WIDTH4) + new Vector6[A](prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, prefix5, len12345, data6, suffix5, suffix4, suffix3, suffix2, suffix1, len) + } + res + } + } + + @inline private[this] def prefixOr[T <: AnyRef](n: Int, a: Array[T]): Array[T] = { + val p = slices(prefixIdx(n)) + if(p ne null) p.asInstanceOf[Array[T]] else a + } + + @inline private[this] def suffixOr[T <: AnyRef](n: Int, a: Array[T]): Array[T] = { + val s = slices(suffixIdx(n)) + if(s ne null) s.asInstanceOf[Array[T]] else a + } + + @inline private[this] def dataOr[T <: AnyRef](n: Int, a: Array[T]): Array[T] = { + val p = slices(prefixIdx(n)) + if(p ne null) p.asInstanceOf[Array[T]] + else { + val s = slices(suffixIdx(n)) + if(s ne null) s.asInstanceOf[Array[T]] else a + } + } + + /** Ensure prefix is not empty */ + private[this] def balancePrefix(n: Int): Unit = { + if(slices(prefixIdx(n)) eq null) { + if(n == maxDim) { + slices(prefixIdx(n)) = slices(suffixIdx(n)) + slices(suffixIdx(n)) = null + } else { + balancePrefix(n+1) + val preN1 = slices(prefixIdx(n+1)).asInstanceOf[Array[Array[AnyRef]]] + //assert(preN1 ne null) + slices(prefixIdx(n)) = preN1(0) + if(preN1.length == 1) { + slices(prefixIdx(n+1)) = null + if((maxDim == n+1) && (slices(suffixIdx(n+1)) eq null)) maxDim = n + } else { + slices(prefixIdx(n+1)) = copyOfRange(preN1, 1, preN1.length).asInstanceOf[Array[AnyRef]] + } + } + } + } + + /** Ensure suffix is not empty */ + private[this] def balanceSuffix(n: Int): Unit = { + if(slices(suffixIdx(n)) eq null) { + if(n == maxDim) { + slices(suffixIdx(n)) = slices(prefixIdx(n)) + slices(prefixIdx(n)) = null + } else { + balanceSuffix(n+1) + val sufN1 = slices(suffixIdx(n+1)).asInstanceOf[Array[Array[AnyRef]]] + //assert(sufN1 ne null, s"n=$n, maxDim=$maxDim, slices=${slices.mkString(",")}") + slices(suffixIdx(n)) = sufN1(sufN1.length-1) + if(sufN1.length == 1) { + slices(suffixIdx(n+1)) = null + if((maxDim == n+1) && (slices(prefixIdx(n+1)) eq null)) maxDim = n + } else { + slices(suffixIdx(n+1)) = copyOfRange(sufN1, 0, sufN1.length-1).asInstanceOf[Array[AnyRef]] + } + } + } + } + + override def toString: String = + s"VectorSliceBuilder(lo=$lo, hi=$hi, len=$len, pos=$pos, maxDim=$maxDim)" + + private[immutable] def getSlices: Array[Array[AnyRef]] = slices +} + + +final class VectorBuilder[A] extends ReusableBuilder[A, Vector[A]] { + + private[this] var a6: Arr6 = _ + private[this] var a5: Arr5 = _ + private[this] var a4: Arr4 = _ + private[this] var a3: Arr3 = _ + private[this] var a2: Arr2 = _ + private[this] var a1: Arr1 = new Arr1(WIDTH) + private[this] var len1, lenRest, offset = 0 + private[this] var prefixIsRightAligned = false + private[this] var depth = 1 + + @inline private[this] final def setLen(i: Int): Unit = { + len1 = i & MASK + lenRest = i - len1 + } + + override def knownSize: Int = len1 + lenRest - offset + + @inline def size: Int = knownSize + @inline def isEmpty: Boolean = knownSize == 0 + @inline def nonEmpty: Boolean = knownSize != 0 + + def clear(): Unit = { + a6 = null + a5 = null + a4 = null + a3 = null + a2 = null + a1 = new Arr1(WIDTH) + len1 = 0 + lenRest = 0 + offset = 0 + prefixIsRightAligned = false + depth = 1 + } + + private[immutable] def initSparse(size: Int, elem: A): Unit = { + setLen(size) + Arrays.fill(a1, elem) + if(size > WIDTH) { + a2 = new Array(WIDTH) + Arrays.fill(a2.asInstanceOf[Array[AnyRef]], a1) + if(size > WIDTH2) { + a3 = new Array(WIDTH) + Arrays.fill(a3.asInstanceOf[Array[AnyRef]], a2) + if(size > WIDTH3) { + a4 = new Array(WIDTH) + Arrays.fill(a4.asInstanceOf[Array[AnyRef]], a3) + if(size > WIDTH4) { + a5 = new Array(WIDTH) + Arrays.fill(a5.asInstanceOf[Array[AnyRef]], a4) + if(size > WIDTH5) { + a6 = new Array(LASTWIDTH) + Arrays.fill(a6.asInstanceOf[Array[AnyRef]], a5) + depth = 6 + } else depth = 5 + } else depth = 4 + } else depth = 3 + } else depth = 2 + } else depth = 1 + } + + private[immutable] def initFrom(prefix1: Arr1): Unit = { + depth = 1 + setLen(prefix1.length) + a1 = copyOrUse(prefix1, 0, WIDTH) + if(len1 == 0 && lenRest > 0) { + // force advance() on next addition: + len1 = WIDTH + lenRest -= WIDTH + } + } + + private[immutable] def initFrom(v: Vector[_]): this.type = { + (v.vectorSliceCount: @switch) match { + case 0 => + case 1 => + val v1 = v.asInstanceOf[Vector1[_]] + depth = 1 + setLen(v1.prefix1.length) + a1 = copyOrUse(v1.prefix1, 0, WIDTH) + case 3 => + val v2 = v.asInstanceOf[Vector2[_]] + val d2 = v2.data2 + a1 = copyOrUse(v2.suffix1, 0, WIDTH) + depth = 2 + offset = WIDTH - v2.len1 + setLen(v2.length0 + offset) + a2 = new Arr2(WIDTH) + a2(0) = v2.prefix1 + System.arraycopy(d2, 0, a2, 1, d2.length) + a2(d2.length+1) = a1 + case 5 => + val v3 = v.asInstanceOf[Vector3[_]] + val d3 = v3.data3 + val s2 = v3.suffix2 + a1 = copyOrUse(v3.suffix1, 0, WIDTH) + depth = 3 + offset = WIDTH2 - v3.len12 + setLen(v3.length0 + offset) + a3 = new Arr3(WIDTH) + a3(0) = copyPrepend(v3.prefix1, v3.prefix2) + System.arraycopy(d3, 0, a3, 1, d3.length) + a2 = copyOf(s2, WIDTH) + a3(d3.length+1) = a2 + a2(s2.length) = a1 + case 7 => + val v4 = v.asInstanceOf[Vector4[_]] + val d4 = v4.data4 + val s3 = v4.suffix3 + val s2 = v4.suffix2 + a1 = copyOrUse(v4.suffix1, 0, WIDTH) + depth = 4 + offset = WIDTH3 - v4.len123 + setLen(v4.length0 + offset) + a4 = new Arr4(WIDTH) + a4(0) = copyPrepend(copyPrepend(v4.prefix1, v4.prefix2), v4.prefix3) + System.arraycopy(d4, 0, a4, 1, d4.length) + a3 = copyOf(s3, WIDTH) + a2 = copyOf(s2, WIDTH) + a4(d4.length+1) = a3 + a3(s3.length) = a2 + a2(s2.length) = a1 + case 9 => + val v5 = v.asInstanceOf[Vector5[_]] + val d5 = v5.data5 + val s4 = v5.suffix4 + val s3 = v5.suffix3 + val s2 = v5.suffix2 + a1 = copyOrUse(v5.suffix1, 0, WIDTH) + depth = 5 + offset = WIDTH4 - v5.len1234 + setLen(v5.length0 + offset) + a5 = new Arr5(WIDTH) + a5(0) = copyPrepend(copyPrepend(copyPrepend(v5.prefix1, v5.prefix2), v5.prefix3), v5.prefix4) + System.arraycopy(d5, 0, a5, 1, d5.length) + a4 = copyOf(s4, WIDTH) + a3 = copyOf(s3, WIDTH) + a2 = copyOf(s2, WIDTH) + a5(d5.length+1) = a4 + a4(s4.length) = a3 + a3(s3.length) = a2 + a2(s2.length) = a1 + case 11 => + val v6 = v.asInstanceOf[Vector6[_]] + val d6 = v6.data6 + val s5 = v6.suffix5 + val s4 = v6.suffix4 + val s3 = v6.suffix3 + val s2 = v6.suffix2 + a1 = copyOrUse(v6.suffix1, 0, WIDTH) + depth = 6 + offset = WIDTH5 - v6.len12345 + setLen(v6.length0 + offset) + a6 = new Arr6(LASTWIDTH) + a6(0) = copyPrepend(copyPrepend(copyPrepend(copyPrepend(v6.prefix1, v6.prefix2), v6.prefix3), v6.prefix4), v6.prefix5) + System.arraycopy(d6, 0, a6, 1, d6.length) + a5 = copyOf(s5, WIDTH) + a4 = copyOf(s4, WIDTH) + a3 = copyOf(s3, WIDTH) + a2 = copyOf(s2, WIDTH) + a6(d6.length+1) = a5 + a5(s5.length) = a4 + a4(s4.length) = a3 + a3(s3.length) = a2 + a2(s2.length) = a1 + } + if(len1 == 0 && lenRest > 0) { + // force advance() on next addition: + len1 = WIDTH + lenRest -= WIDTH + } + this + } + + //TODO Make public; this method is only private for binary compatibility + private[collection] def alignTo(before: Int, bigVector: Vector[A]): this.type = { + if (len1 != 0 || lenRest != 0) + throw new UnsupportedOperationException("A non-empty VectorBuilder cannot be aligned retrospectively. Please call .reset() or use a new VectorBuilder.") + val (prefixLength, maxPrefixLength) = bigVector match { + case Vector0 => (0, 1) + case v1: Vector1[_] => (0, 1) + case v2: Vector2[_] => (v2.len1, WIDTH) + case v3: Vector3[_] => (v3.len12, WIDTH2) + case v4: Vector4[_] => (v4.len123, WIDTH3) + case v5: Vector5[_] => (v5.len1234, WIDTH4) + case v6: Vector6[_] => (v6.len12345, WIDTH5) + } + if (maxPrefixLength == 1) return this // does not really make sense to align for <= 32 element-vector + val overallPrefixLength = (before + prefixLength) % maxPrefixLength + offset = (maxPrefixLength - overallPrefixLength) % maxPrefixLength + // pretend there are already `offset` elements added + advanceN(offset & ~MASK) + len1 = offset & MASK + prefixIsRightAligned = true + this + } + + /** + * Removes `offset` leading `null`s in the prefix. + * This is needed after calling `alignTo` and subsequent additions, + * directly before the result is used for creating a new Vector. + * Note that the outermost array keeps its length to keep the + * Builder re-usable. + * + * example: + * a2 = Array(null, ..., null, Array(null, .., null, 0, 1, .., x), Array(x+1, .., x+32), ...) + * becomes + * a2 = Array(Array(0, 1, .., x), Array(x+1, .., x+32), ..., ?, ..., ?) + */ + private[this] def leftAlignPrefix(): Unit = { + @inline def shrinkOffsetIfToLarge(width: Int): Unit = { + val newOffset = offset % width + lenRest -= offset - newOffset + offset = newOffset + } + var a: Array[AnyRef] = null // the array we modify + var aParent: Array[AnyRef] = null // a's parent, so aParent(0) == a + if (depth >= 6) { + a = a6.asInstanceOf[Array[AnyRef]] + val i = offset >>> BITS5 + if (i > 0) System.arraycopy(a, i, a, 0, LASTWIDTH - i) + shrinkOffsetIfToLarge(WIDTH5) + if ((lenRest >>> BITS5) == 0) depth = 5 + aParent = a + a = a(0).asInstanceOf[Array[AnyRef]] + } + if (depth >= 5) { + if (a == null) a = a5.asInstanceOf[Array[AnyRef]] + val i = (offset >>> BITS4) & MASK + if (depth == 5) { + if (i > 0) System.arraycopy(a, i, a, 0, WIDTH - i) + a5 = a.asInstanceOf[Arr5] + shrinkOffsetIfToLarge(WIDTH4) + if ((lenRest >>> BITS4) == 0) depth = 4 + } else { + if (i > 0) a = copyOfRange(a, i, WIDTH) + aParent(0) = a + } + aParent = a + a = a(0).asInstanceOf[Array[AnyRef]] + } + if (depth >= 4) { + if (a == null) a = a4.asInstanceOf[Array[AnyRef]] + val i = (offset >>> BITS3) & MASK + if (depth == 4) { + if (i > 0) System.arraycopy(a, i, a, 0, WIDTH - i) + a4 = a.asInstanceOf[Arr4] + shrinkOffsetIfToLarge(WIDTH3) + if ((lenRest >>> BITS3) == 0) depth = 3 + } else { + if (i > 0) a = copyOfRange(a, i, WIDTH) + aParent(0) = a + } + aParent = a + a = a(0).asInstanceOf[Array[AnyRef]] + } + if (depth >= 3) { + if (a == null) a = a3.asInstanceOf[Array[AnyRef]] + val i = (offset >>> BITS2) & MASK + if (depth == 3) { + if (i > 0) System.arraycopy(a, i, a, 0, WIDTH - i) + a3 = a.asInstanceOf[Arr3] + shrinkOffsetIfToLarge(WIDTH2) + if ((lenRest >>> BITS2) == 0) depth = 2 + } else { + if (i > 0) a = copyOfRange(a, i, WIDTH) + aParent(0) = a + } + aParent = a + a = a(0).asInstanceOf[Array[AnyRef]] + } + if (depth >= 2) { + if (a == null) a = a2.asInstanceOf[Array[AnyRef]] + val i = (offset >>> BITS) & MASK + if (depth == 2) { + if (i > 0) System.arraycopy(a, i, a, 0, WIDTH - i) + a2 = a.asInstanceOf[Arr2] + shrinkOffsetIfToLarge(WIDTH) + if ((lenRest >>> BITS) == 0) depth = 1 + } else { + if (i > 0) a = copyOfRange(a, i, WIDTH) + aParent(0) = a + } + aParent = a + a = a(0).asInstanceOf[Array[AnyRef]] + } + if (depth >= 1) { + if (a == null) a = a1.asInstanceOf[Array[AnyRef]] + val i = offset & MASK + if (depth == 1) { + if (i > 0) System.arraycopy(a, i, a, 0, WIDTH - i) + a1 = a.asInstanceOf[Arr1] + len1 -= offset + offset = 0 + } else { + if (i > 0) a = copyOfRange(a, i, WIDTH) + aParent(0) = a + } + } + prefixIsRightAligned = false + } + + def addOne(elem: A): this.type = { + if(len1 == WIDTH) advance() + a1(len1) = elem.asInstanceOf[AnyRef] + len1 += 1 + this + } + + private[this] def addArr1(data: Arr1): Unit = { + val dl = data.length + if(dl > 0) { + if(len1 == WIDTH) advance() + val copy1 = mmin(WIDTH-len1, dl) + val copy2 = dl - copy1 + System.arraycopy(data, 0, a1, len1, copy1) + len1 += copy1 + if(copy2 > 0) { + advance() + System.arraycopy(data, copy1, a1, 0, copy2) + len1 += copy2 + } + } + } + + private[this] def addArrN(slice: Array[AnyRef], dim: Int): Unit = { +// assert(dim >= 2) +// assert(lenRest % WIDTH == 0) +// assert(len1 == 0 || len1 == WIDTH) + if (slice.isEmpty) return + if (len1 == WIDTH) advance() + val sl = slice.length + (dim: @switch) match { + case 2 => + // lenRest is always a multiple of WIDTH + val copy1 = mmin(((WIDTH2 - lenRest) >>> BITS) & MASK, sl) + val copy2 = sl - copy1 + val destPos = (lenRest >>> BITS) & MASK + System.arraycopy(slice, 0, a2, destPos, copy1) + advanceN(WIDTH * copy1) + if (copy2 > 0) { + System.arraycopy(slice, copy1, a2, 0, copy2) + advanceN(WIDTH * copy2) + } + case 3 => + if (lenRest % WIDTH2 != 0) { + // lenRest is not multiple of WIDTH2, so this slice does not align, need to try lower dimension + slice.foreach(e => addArrN(e.asInstanceOf[Array[AnyRef]], 2)) + return + } + val copy1 = mmin(((WIDTH3 - lenRest) >>> BITS2) & MASK, sl) + val copy2 = sl - copy1 + val destPos = (lenRest >>> BITS2) & MASK + System.arraycopy(slice, 0, a3, destPos, copy1) + advanceN(WIDTH2 * copy1) + if (copy2 > 0) { + System.arraycopy(slice, copy1, a3, 0, copy2) + advanceN(WIDTH2 * copy2) + } + case 4 => + if (lenRest % WIDTH3 != 0) { + // lenRest is not multiple of WIDTH3, so this slice does not align, need to try lower dimensions + slice.foreach(e => addArrN(e.asInstanceOf[Array[AnyRef]], 3)) + return + } + val copy1 = mmin(((WIDTH4 - lenRest) >>> BITS3) & MASK, sl) + val copy2 = sl - copy1 + val destPos = (lenRest >>> BITS3) & MASK + System.arraycopy(slice, 0, a4, destPos, copy1) + advanceN(WIDTH3 * copy1) + if (copy2 > 0) { + System.arraycopy(slice, copy1, a4, 0, copy2) + advanceN(WIDTH3 * copy2) + } + case 5 => + if (lenRest % WIDTH4 != 0) { + // lenRest is not multiple of WIDTH4, so this slice does not align, need to try lower dimensions + slice.foreach(e => addArrN(e.asInstanceOf[Array[AnyRef]], 4)) + return + } + val copy1 = mmin(((WIDTH5 - lenRest) >>> BITS4) & MASK, sl) + val copy2 = sl - copy1 + val destPos = (lenRest >>> BITS4) & MASK + System.arraycopy(slice, 0, a5, destPos, copy1) + advanceN(WIDTH4 * copy1) + if (copy2 > 0) { + System.arraycopy(slice, copy1, a5, 0, copy2) + advanceN(WIDTH4 * copy2) + } + case 6 => // note width is now LASTWIDTH + if (lenRest % WIDTH5 != 0) { + // lenRest is not multiple of WIDTH5, so this slice does not align, need to try lower dimensions + slice.foreach(e => addArrN(e.asInstanceOf[Array[AnyRef]], 5)) + return + } + val copy1 = sl + // there is no copy2 because there can't be another a6 to copy to + val destPos = lenRest >>> BITS5 + if (destPos + copy1 > LASTWIDTH) + throw new IllegalArgumentException("exceeding 2^31 elements") + System.arraycopy(slice, 0, a6, destPos, copy1) + advanceN(WIDTH5 * copy1) + } + } + + private[this] def addVector(xs: Vector[A]): this.type = { + val sliceCount = xs.vectorSliceCount + var sliceIdx = 0 + while(sliceIdx < sliceCount) { + val slice = xs.vectorSlice(sliceIdx) + vectorSliceDim(sliceCount, sliceIdx) match { + case 1 => addArr1(slice.asInstanceOf[Arr1]) + case n if len1 == WIDTH || len1 == 0 => + addArrN(slice.asInstanceOf[Array[AnyRef]], n) + case n => foreachRec(n-2, slice, addArr1) + } + sliceIdx += 1 + } + this + } + + override def addAll(xs: IterableOnce[A]^): this.type = xs match { + case v: Vector[_] => + if(len1 == 0 && lenRest == 0 && !prefixIsRightAligned) initFrom(v) + else addVector(v.asInstanceOf[Vector[A]]) + case _ => + super.addAll(xs) + } + + private[this] def advance(): Unit = { + val idx = lenRest + WIDTH + val xor = idx ^ lenRest + lenRest = idx + len1 = 0 + advance1(idx, xor) + } + + private[this] def advanceN(n: Int): Unit = if (n > 0) { + // assert(n % 32 == 0) + val idx = lenRest + n + val xor = idx ^ lenRest + lenRest = idx + len1 = 0 + advance1(idx, xor) + } + + private[this] def advance1(idx: Int, xor: Int): Unit = { + if (xor <= 0) { // level = 6 or something very unexpected happened + throw new IllegalArgumentException(s"advance1($idx, $xor): a1=$a1, a2=$a2, a3=$a3, a4=$a4, a5=$a5, a6=$a6, depth=$depth") + } else if (xor < WIDTH2) { // level = 1 + if (depth <= 1) { a2 = new Array(WIDTH); a2(0) = a1; depth = 2 } + a1 = new Array(WIDTH) + a2((idx >>> BITS) & MASK) = a1 + } else if (xor < WIDTH3) { // level = 2 + if (depth <= 2) { a3 = new Array(WIDTH); a3(0) = a2; depth = 3 } + a1 = new Array(WIDTH) + a2 = new Array(WIDTH) + a2((idx >>> BITS) & MASK) = a1 + a3((idx >>> BITS2) & MASK) = a2 + } else if (xor < WIDTH4) { // level = 3 + if (depth <= 3) { a4 = new Array(WIDTH); a4(0) = a3; depth = 4 } + a1 = new Array(WIDTH) + a2 = new Array(WIDTH) + a3 = new Array(WIDTH) + a2((idx >>> BITS) & MASK) = a1 + a3((idx >>> BITS2) & MASK) = a2 + a4((idx >>> BITS3) & MASK) = a3 + } else if (xor < WIDTH5) { // level = 4 + if (depth <= 4) { a5 = new Array(WIDTH); a5(0) = a4; depth = 5 } + a1 = new Array(WIDTH) + a2 = new Array(WIDTH) + a3 = new Array(WIDTH) + a4 = new Array(WIDTH) + a2((idx >>> BITS) & MASK) = a1 + a3((idx >>> BITS2) & MASK) = a2 + a4((idx >>> BITS3) & MASK) = a3 + a5((idx >>> BITS4) & MASK) = a4 + } else { // level = 5 + if (depth <= 5) { a6 = new Array(LASTWIDTH); a6(0) = a5; depth = 6 } + a1 = new Array(WIDTH) + a2 = new Array(WIDTH) + a3 = new Array(WIDTH) + a4 = new Array(WIDTH) + a5 = new Array(WIDTH) + a2((idx >>> BITS) & MASK) = a1 + a3((idx >>> BITS2) & MASK) = a2 + a4((idx >>> BITS3) & MASK) = a3 + a5((idx >>> BITS4) & MASK) = a4 + a6(idx >>> BITS5) = a5 + } + } + + def result(): Vector[A] = { + if (prefixIsRightAligned) leftAlignPrefix() + val len = len1 + lenRest + val realLen = len - offset + if(realLen == 0) Vector.empty + else if(len < 0) throw new IndexOutOfBoundsException(s"Vector cannot have negative size $len") + else if(len <= WIDTH) { + new Vector1(copyIfDifferentSize(a1, realLen)) + } else if(len <= WIDTH2) { + val i1 = (len-1) & MASK + val i2 = (len-1) >>> BITS + val data = copyOfRange(a2, 1, i2) + val prefix1 = a2(0) + val suffix1 = copyIfDifferentSize(a2(i2), i1+1) + new Vector2(prefix1, WIDTH-offset, data, suffix1, realLen) + } else if(len <= WIDTH3) { + val i1 = (len-1) & MASK + val i2 = ((len-1) >>> BITS) & MASK + val i3 = ((len-1) >>> BITS2) + val data = copyOfRange(a3, 1, i3) + val prefix2 = copyTail(a3(0)) + val prefix1 = a3(0)(0) + val suffix2 = copyOf(a3(i3), i2) + val suffix1 = copyIfDifferentSize(a3(i3)(i2), i1+1) + val len1 = prefix1.length + val len12 = len1 + prefix2.length*WIDTH + new Vector3(prefix1, len1, prefix2, len12, data, suffix2, suffix1, realLen) + } else if(len <= WIDTH4) { + val i1 = (len-1) & MASK + val i2 = ((len-1) >>> BITS) & MASK + val i3 = ((len-1) >>> BITS2) & MASK + val i4 = ((len-1) >>> BITS3) + val data = copyOfRange(a4, 1, i4) + val prefix3 = copyTail(a4(0)) + val prefix2 = copyTail(a4(0)(0)) + val prefix1 = a4(0)(0)(0) + val suffix3 = copyOf(a4(i4), i3) + val suffix2 = copyOf(a4(i4)(i3), i2) + val suffix1 = copyIfDifferentSize(a4(i4)(i3)(i2), i1+1) + val len1 = prefix1.length + val len12 = len1 + prefix2.length*WIDTH + val len123 = len12 + prefix3.length*WIDTH2 + new Vector4(prefix1, len1, prefix2, len12, prefix3, len123, data, suffix3, suffix2, suffix1, realLen) + } else if(len <= WIDTH5) { + val i1 = (len-1) & MASK + val i2 = ((len-1) >>> BITS) & MASK + val i3 = ((len-1) >>> BITS2) & MASK + val i4 = ((len-1) >>> BITS3) & MASK + val i5 = ((len-1) >>> BITS4) + val data = copyOfRange(a5, 1, i5) + val prefix4 = copyTail(a5(0)) + val prefix3 = copyTail(a5(0)(0)) + val prefix2 = copyTail(a5(0)(0)(0)) + val prefix1 = a5(0)(0)(0)(0) + val suffix4 = copyOf(a5(i5), i4) + val suffix3 = copyOf(a5(i5)(i4), i3) + val suffix2 = copyOf(a5(i5)(i4)(i3), i2) + val suffix1 = copyIfDifferentSize(a5(i5)(i4)(i3)(i2), i1+1) + val len1 = prefix1.length + val len12 = len1 + prefix2.length*WIDTH + val len123 = len12 + prefix3.length*WIDTH2 + val len1234 = len123 + prefix4.length*WIDTH3 + new Vector5(prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, data, suffix4, suffix3, suffix2, suffix1, realLen) + } else { + val i1 = (len-1) & MASK + val i2 = ((len-1) >>> BITS) & MASK + val i3 = ((len-1) >>> BITS2) & MASK + val i4 = ((len-1) >>> BITS3) & MASK + val i5 = ((len-1) >>> BITS4) & MASK + val i6 = ((len-1) >>> BITS5) + val data = copyOfRange(a6, 1, i6) + val prefix5 = copyTail(a6(0)) + val prefix4 = copyTail(a6(0)(0)) + val prefix3 = copyTail(a6(0)(0)(0)) + val prefix2 = copyTail(a6(0)(0)(0)(0)) + val prefix1 = a6(0)(0)(0)(0)(0) + val suffix5 = copyOf(a6(i6), i5) + val suffix4 = copyOf(a6(i6)(i5), i4) + val suffix3 = copyOf(a6(i6)(i5)(i4), i3) + val suffix2 = copyOf(a6(i6)(i5)(i4)(i3), i2) + val suffix1 = copyIfDifferentSize(a6(i6)(i5)(i4)(i3)(i2), i1+1) + val len1 = prefix1.length + val len12 = len1 + prefix2.length*WIDTH + val len123 = len12 + prefix3.length*WIDTH2 + val len1234 = len123 + prefix4.length*WIDTH3 + val len12345 = len1234 + prefix5.length*WIDTH4 + new Vector6(prefix1, len1, prefix2, len12, prefix3, len123, prefix4, len1234, prefix5, len12345, data, suffix5, suffix4, suffix3, suffix2, suffix1, realLen) + } + } + + override def toString: String = + s"VectorBuilder(len1=$len1, lenRest=$lenRest, offset=$offset, depth=$depth)" + + private[immutable] def getData: Array[Array[_]] = Array[Array[AnyRef]]( + a1, a2.asInstanceOf[Array[AnyRef]], a3.asInstanceOf[Array[AnyRef]], a4.asInstanceOf[Array[AnyRef]], + a5.asInstanceOf[Array[AnyRef]], a6.asInstanceOf[Array[AnyRef]] + ).asInstanceOf[Array[Array[_]]] +} + + +/** Compile-time definitions for Vector. No references to this object should appear in bytecode. */ +private[immutable] object VectorInline { + // compile-time numeric constants + final val BITS = 5 + final val WIDTH = 1 << BITS + final val MASK = WIDTH - 1 + final val BITS2 = BITS * 2 + final val WIDTH2 = 1 << BITS2 + final val BITS3 = BITS * 3 + final val WIDTH3 = 1 << BITS3 + final val BITS4 = BITS * 4 + final val WIDTH4 = 1 << BITS4 + final val BITS5 = BITS * 5 + final val WIDTH5 = 1 << BITS5 + final val LASTWIDTH = WIDTH << 1 // 1 extra bit in the last level to go up to Int.MaxValue (2^31-1) instead of 2^30: + final val Log2ConcatFaster = 5 + final val AlignToFaster = 64 + + type Arr1 = Array[AnyRef] + type Arr2 = Array[Array[AnyRef]] + type Arr3 = Array[Array[Array[AnyRef]]] + type Arr4 = Array[Array[Array[Array[AnyRef]]]] + type Arr5 = Array[Array[Array[Array[Array[AnyRef]]]]] + type Arr6 = Array[Array[Array[Array[Array[Array[AnyRef]]]]]] + + /** Dimension of the slice at index */ + @inline def vectorSliceDim(count: Int, idx: Int): Int = { + val c = count/2 + c+1-abs(idx-c) + } + + @inline def copyOrUse[T <: AnyRef](a: Array[T], start: Int, end: Int): Array[T] = + if(start == 0 && end == a.length) a else copyOfRange[T](a, start, end) + + @inline final def copyTail[T <: AnyRef](a: Array[T]): Array[T] = copyOfRange[T](a, 1, a.length) + + @inline final def copyInit[T <: AnyRef](a: Array[T]): Array[T] = copyOfRange[T](a, 0, a.length-1) + + @inline final def copyIfDifferentSize[T <: AnyRef](a: Array[T], len: Int): Array[T] = + if(a.length == len) a else copyOf[T](a, len) + + @inline final def wrap1(x: Any ): Arr1 = { val a = new Arr1(1); a(0) = x.asInstanceOf[AnyRef]; a } + @inline final def wrap2(x: Arr1): Arr2 = { val a = new Arr2(1); a(0) = x; a } + @inline final def wrap3(x: Arr2): Arr3 = { val a = new Arr3(1); a(0) = x; a } + @inline final def wrap4(x: Arr3): Arr4 = { val a = new Arr4(1); a(0) = x; a } + @inline final def wrap5(x: Arr4): Arr5 = { val a = new Arr5(1); a(0) = x; a } + + @inline final def copyUpdate(a1: Arr1, idx1: Int, elem: Any): Arr1 = { + val a1c = a1.clone() + a1c(idx1) = elem.asInstanceOf[AnyRef] + a1c + } + + @inline final def copyUpdate(a2: Arr2, idx2: Int, idx1: Int, elem: Any): Arr2 = { + val a2c = a2.clone() + a2c(idx2) = copyUpdate(a2c(idx2), idx1, elem) + a2c + } + + @inline final def copyUpdate(a3: Arr3, idx3: Int, idx2: Int, idx1: Int, elem: Any): Arr3 = { + val a3c = a3.clone() + a3c(idx3) = copyUpdate(a3c(idx3), idx2, idx1, elem) + a3c + } + + @inline final def copyUpdate(a4: Arr4, idx4: Int, idx3: Int, idx2: Int, idx1: Int, elem: Any): Arr4 = { + val a4c = a4.clone() + a4c(idx4) = copyUpdate(a4c(idx4), idx3, idx2, idx1, elem) + a4c + } + + @inline final def copyUpdate(a5: Arr5, idx5: Int, idx4: Int, idx3: Int, idx2: Int, idx1: Int, elem: Any): Arr5 = { + val a5c = a5.clone() + a5c(idx5) = copyUpdate(a5c(idx5), idx4, idx3, idx2, idx1, elem) + a5c + } + + @inline final def copyUpdate(a6: Arr6, idx6: Int, idx5: Int, idx4: Int, idx3: Int, idx2: Int, idx1: Int, elem: Any): Arr6 = { + val a6c = a6.clone() + a6c(idx6) = copyUpdate(a6c(idx6), idx5, idx4, idx3, idx2, idx1, elem) + a6c + } + + @inline final def concatArrays[T <: AnyRef](a: Array[T], b: Array[T]): Array[T] = { + val dest = copyOf[T](a, a.length+b.length) + System.arraycopy(b, 0, dest, a.length, b.length) + dest + } +} + + +/** Helper methods and constants for Vector. */ +private object VectorStatics { + + final def copyAppend1(a: Arr1, elem: Any): Arr1 = { + val alen = a.length + val ac = new Arr1(alen+1) + System.arraycopy(a, 0, ac, 0, alen) + ac(alen) = elem.asInstanceOf[AnyRef] + ac + } + + final def copyAppend[T <: AnyRef](a: Array[T], elem: T): Array[T] = { + val ac = copyOf(a, a.length+1) + ac(ac.length-1) = elem + ac + } + + final def copyPrepend1(elem: Any, a: Arr1): Arr1 = { + val ac = new Arr1(a.length+1) + System.arraycopy(a, 0, ac, 1, a.length) + ac(0) = elem.asInstanceOf[AnyRef] + ac + } + + final def copyPrepend[T <: AnyRef](elem: T, a: Array[T]): Array[T] = { + val ac = java.lang.reflect.Array.newInstance(a.getClass.getComponentType, a.length+1).asInstanceOf[Array[T]] + System.arraycopy(a, 0, ac, 1, a.length) + ac(0) = elem + ac + } + + final val empty1: Arr1 = new Array(0) + final val empty2: Arr2 = new Array(0) + final val empty3: Arr3 = new Array(0) + final val empty4: Arr4 = new Array(0) + final val empty5: Arr5 = new Array(0) + final val empty6: Arr6 = new Array(0) + + final def foreachRec[T <: AnyRef, A, U](level: Int, a: Array[T], f: A => U): Unit = { + var i = 0 + val len = a.length + if(level == 0) { + while(i < len) { + f(a(i).asInstanceOf[A]) + i += 1 + } + } else { + val l = level-1 + while(i < len) { + foreachRec(l, a(i).asInstanceOf[Array[AnyRef]], f) + i += 1 + } + } + } + + final def mapElems1[A, B](a: Arr1, f: A => B): Arr1 = { + var i = 0 + while(i < a.length) { + val v1 = a(i).asInstanceOf[AnyRef] + val v2 = f(v1.asInstanceOf[A]).asInstanceOf[AnyRef] + if(v1 ne v2) + return mapElems1Rest(a, f, i, v2) + i += 1 + } + a + } + + final def mapElems1Rest[A, B](a: Arr1, f: A => B, at: Int, v2: AnyRef): Arr1 = { + val ac = new Arr1(a.length) + if(at > 0) System.arraycopy(a, 0, ac, 0, at) + ac(at) = v2 + var i = at+1 + while(i < a.length) { + ac(i) = f(a(i).asInstanceOf[A]).asInstanceOf[AnyRef] + i += 1 + } + ac + } + + final def mapElems[A, B, T <: AnyRef](n: Int, a: Array[T], f: A => B): Array[T] = { + if(n == 1) + mapElems1[A, B](a.asInstanceOf[Arr1], f).asInstanceOf[Array[T]] + else { + var i = 0 + while(i < a.length) { + val v1 = a(i) + val v2 = mapElems(n-1, v1.asInstanceOf[Array[AnyRef]], f) + if(v1 ne v2) + return mapElemsRest(n, a, f, i, v2) + i += 1 + } + a + } + } + + final def mapElemsRest[A, B, T <: AnyRef](n: Int, a: Array[T], f: A => B, at: Int, v2: AnyRef): Array[T] = { + val ac = java.lang.reflect.Array.newInstance(a.getClass.getComponentType, a.length).asInstanceOf[Array[AnyRef]] + if(at > 0) System.arraycopy(a, 0, ac, 0, at) + ac(at) = v2 + var i = at+1 + while(i < a.length) { + ac(i) = mapElems(n-1, a(i).asInstanceOf[Array[AnyRef]], f) + i += 1 + } + ac.asInstanceOf[Array[T]] + } + + final def prepend1IfSpace(prefix1: Arr1, xs: IterableOnce[_]^): Arr1 = xs match { + case it: Iterable[_] => + if(it.sizeCompare(WIDTH-prefix1.length) <= 0) { + it.size match { + case 0 => null + case 1 => copyPrepend(it.head.asInstanceOf[AnyRef], prefix1) + case s => + val prefix1b = new Arr1(prefix1.length + s) + System.arraycopy(prefix1, 0, prefix1b, s, prefix1.length) + it.copyToArray(prefix1b.asInstanceOf[Array[Any]], 0) + prefix1b + } + } else null + case it => + val s = it.knownSize + if(s > 0 && s <= WIDTH-prefix1.length) { + val prefix1b = new Arr1(prefix1.length + s) + System.arraycopy(prefix1, 0, prefix1b, s, prefix1.length) + it.iterator.copyToArray(prefix1b.asInstanceOf[Array[Any]], 0) + prefix1b + } else null + } + + final def append1IfSpace(suffix1: Arr1, xs: IterableOnce[_]^): Arr1 = xs match { + case it: Iterable[_] => + if(it.sizeCompare(WIDTH-suffix1.length) <= 0) { + it.size match { + case 0 => null + case 1 => copyAppend(suffix1, it.head.asInstanceOf[AnyRef]) + case s => + val suffix1b = copyOf(suffix1, suffix1.length + s) + it.copyToArray(suffix1b.asInstanceOf[Array[Any]], suffix1.length) + suffix1b + } + } else null + case it => + val s = it.knownSize + if(s > 0 && s <= WIDTH-suffix1.length) { + val suffix1b = copyOf(suffix1, suffix1.length + s) + it.iterator.copyToArray(suffix1b.asInstanceOf[Array[Any]], suffix1.length) + suffix1b + } else null + } +} + + +private final class NewVectorIterator[A](v: Vector[A], private[this] var totalLength: Int, private[this] val sliceCount: Int) extends Iterator[A] with java.lang.Cloneable { + + private[this] var a1: Arr1 = v.prefix1 + private[this] var a2: Arr2 = _ + private[this] var a3: Arr3 = _ + private[this] var a4: Arr4 = _ + private[this] var a5: Arr5 = _ + private[this] var a6: Arr6 = _ + private[this] var a1len = a1.length + private[this] var i1 = 0 // current index in a1 + private[this] var oldPos = 0 + private[this] var len1 = totalLength // remaining length relative to a1 + + private[this] var sliceIdx = 0 + private[this] var sliceDim = 1 + private[this] var sliceStart = 0 // absolute position + private[this] var sliceEnd = a1len // absolute position + + //override def toString: String = + // s"NewVectorIterator(v=$v, totalLength=$totalLength, sliceCount=$sliceCount): a1len=$a1len, len1=$len1, i1=$i1, sliceEnd=$sliceEnd" + + @inline override def knownSize = len1 - i1 + + @inline def hasNext: Boolean = len1 > i1 + + def next(): A = { + if(i1 == a1len) advance() + val r = a1(i1) + i1 += 1 + r.asInstanceOf[A] + } + + private[this] def advanceSlice(): Unit = { + if(!hasNext) Iterator.empty.next() + sliceIdx += 1 + var slice: Array[_ <: AnyRef] = v.vectorSlice(sliceIdx) + while(slice.length == 0) { + sliceIdx += 1 + slice = v.vectorSlice(sliceIdx) + } + sliceStart = sliceEnd + sliceDim = vectorSliceDim(sliceCount, sliceIdx) + (sliceDim: @switch) match { + case 1 => a1 = slice.asInstanceOf[Arr1] + case 2 => a2 = slice.asInstanceOf[Arr2] + case 3 => a3 = slice.asInstanceOf[Arr3] + case 4 => a4 = slice.asInstanceOf[Arr4] + case 5 => a5 = slice.asInstanceOf[Arr5] + case 6 => a6 = slice.asInstanceOf[Arr6] + } + sliceEnd = sliceStart + slice.length * (1 << (BITS*(sliceDim-1))) + if(sliceEnd > totalLength) sliceEnd = totalLength + if(sliceDim > 1) oldPos = (1 << (BITS*sliceDim))-1 + } + + private[this] def advance(): Unit = { + val pos = i1-len1+totalLength + if(pos == sliceEnd) advanceSlice() + if(sliceDim > 1) { + val io = pos - sliceStart + val xor = oldPos ^ io + advanceA(io, xor) + oldPos = io + } + len1 -= i1 + a1len = mmin(a1.length, len1) + i1 = 0 + } + + private[this] def advanceA(io: Int, xor: Int): Unit = { + if(xor < WIDTH2) { + a1 = a2((io >>> BITS) & MASK) + } else if(xor < WIDTH3) { + a2 = a3((io >>> BITS2) & MASK) + a1 = a2(0) + } else if(xor < WIDTH4) { + a3 = a4((io >>> BITS3) & MASK) + a2 = a3(0) + a1 = a2(0) + } else if(xor < WIDTH5) { + a4 = a5((io >>> BITS4) & MASK) + a3 = a4(0) + a2 = a3(0) + a1 = a2(0) + } else { + a5 = a6(io >>> BITS5) + a4 = a5(0) + a3 = a4(0) + a2 = a3(0) + a1 = a2(0) + } + } + + private[this] def setA(io: Int, xor: Int): Unit = { + if(xor < WIDTH2) { + a1 = a2((io >>> BITS) & MASK) + } else if(xor < WIDTH3) { + a2 = a3((io >>> BITS2) & MASK) + a1 = a2((io >>> BITS) & MASK) + } else if(xor < WIDTH4) { + a3 = a4((io >>> BITS3) & MASK) + a2 = a3((io >>> BITS2) & MASK) + a1 = a2((io >>> BITS) & MASK) + } else if(xor < WIDTH5) { + a4 = a5((io >>> BITS4) & MASK) + a3 = a4((io >>> BITS3) & MASK) + a2 = a3((io >>> BITS2) & MASK) + a1 = a2((io >>> BITS) & MASK) + } else { + a5 = a6(io >>> BITS5) + a4 = a5((io >>> BITS4) & MASK) + a3 = a4((io >>> BITS3) & MASK) + a2 = a3((io >>> BITS2) & MASK) + a1 = a2((io >>> BITS) & MASK) + } + } + + override def drop(n: Int): Iterator[A] = { + if(n > 0) { + val oldpos = i1-len1+totalLength + val newpos = mmin(oldpos + n, totalLength) + if(newpos == totalLength) { + i1 = 0 + len1 = 0 + a1len = 0 + } else { + while(newpos >= sliceEnd) advanceSlice() + val io = newpos - sliceStart + if(sliceDim > 1) { + val xor = oldPos ^ io + setA(io, xor) + oldPos = io + } + a1len = a1.length + i1 = io & MASK + len1 = i1 + (totalLength-newpos) + if(a1len > len1) a1len = len1 + } + } + this + } + + override def take(n: Int): Iterator[A] = { + if(n < knownSize) { + val trunc = knownSize - mmax(0, n) + totalLength -= trunc + len1 -= trunc + if(len1 < a1len) a1len = len1 + if(totalLength < sliceEnd) sliceEnd = totalLength + } + this + } + + override def slice(from: Int, until: Int): Iterator[A] = { + val _until = + if(from > 0) { + drop(from) + until - from + } else until + take(_until) + } + + override def copyToArray[sealed B >: A](xs: Array[B], start: Int, len: Int): Int = { + val xsLen = xs.length + val total = IterableOnce.elemsToCopyToArray(knownSize, xsLen, start, len) + var copied = 0 + val isBoxed = xs.isInstanceOf[Array[AnyRef]] + while(copied < total) { + if(i1 == a1len) advance() + val count = mmin(total-copied, a1.length-i1) + if(isBoxed) System.arraycopy(a1, i1, xs, start+copied, count) + else Array.copy(a1, i1, xs, start+copied, count) + i1 += count + copied += count + } + total + } + + override def toVector: Vector[A] = + v.slice(i1-len1+totalLength, totalLength) + + protected[immutable] def split(at: Int): NewVectorIterator[A] = { + val it2 = clone().asInstanceOf[NewVectorIterator[A]] + it2.take(at) + drop(at) + it2 + } +} + + +private abstract class VectorStepperBase[A, Sub >: Null <: Stepper[A], Semi <: Sub](it: NewVectorIterator[A]) + extends Stepper[A] with EfficientSplit { + + protected[this] def build(it: NewVectorIterator[A]): Semi + + final def hasStep: Boolean = it.hasNext + + final def characteristics: Int = Spliterator.ORDERED + Spliterator.SIZED + Spliterator.SUBSIZED + + final def estimateSize: Long = it.knownSize + + def trySplit(): Sub = { + val len = it.knownSize + if(len > 1) build(it.split(len >>> 1)) + else null + } + + override final def iterator: Iterator[A] = it +} + +private class AnyVectorStepper[A](it: NewVectorIterator[A]) + extends VectorStepperBase[A, AnyStepper[A], AnyVectorStepper[A]](it) with AnyStepper[A] { + protected[this] def build(it: NewVectorIterator[A]) = new AnyVectorStepper(it) + def nextStep(): A = it.next() +} + +private class DoubleVectorStepper(it: NewVectorIterator[Double]) + extends VectorStepperBase[Double, DoubleStepper, DoubleVectorStepper](it) with DoubleStepper { + protected[this] def build(it: NewVectorIterator[Double]) = new DoubleVectorStepper(it) + def nextStep(): Double = it.next() +} + +private class IntVectorStepper(it: NewVectorIterator[Int]) + extends VectorStepperBase[Int, IntStepper, IntVectorStepper](it) with IntStepper { + protected[this] def build(it: NewVectorIterator[Int]) = new IntVectorStepper(it) + def nextStep(): Int = it.next() +} + +private class LongVectorStepper(it: NewVectorIterator[Long]) + extends VectorStepperBase[Long, LongStepper, LongVectorStepper](it) with LongStepper { + protected[this] def build(it: NewVectorIterator[Long]) = new LongVectorStepper(it) + def nextStep(): Long = it.next() +} + + +// The following definitions are needed for binary compatibility with ParVector +private[collection] class VectorIterator[+A](_startIndex: Int, private[this] var endIndex: Int) extends AbstractIterator[A] { + private[immutable] var it: NewVectorIterator[A @uncheckedVariance @uncheckedCaptures] = _ + def hasNext: Boolean = it.hasNext + def next(): A = it.next() + private[collection] def remainingElementCount: Int = it.size + private[collection] def remainingVector: Vector[A] = it.toVector +} diff --git a/tests/pos-special/stdlib/collection/immutable/VectorMap.scala b/tests/pos-special/stdlib/collection/immutable/VectorMap.scala new file mode 100644 index 000000000000..0860a0b47f28 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/VectorMap.scala @@ -0,0 +1,277 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.tailrec +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** This class implements immutable maps using a vector/map-based data structure, which preserves insertion order. + * + * Unlike `ListMap`, `VectorMap` has amortized effectively constant lookup at the expense + * of using extra memory and generally lower performance for other operations + * + * @tparam K the type of the keys contained in this vector map. + * @tparam V the type of the values associated with the keys in this vector map. + * + * @define coll immutable vector map + * @define Coll `immutable.VectorMap` + */ +final class VectorMap[K, +V] private ( + private[immutable] val fields: Vector[Any], + private[immutable] val underlying: Map[K, (Int, V)], dropped: Int) + extends AbstractMap[K, V] + with SeqMap[K, V] + with StrictOptimizedMapOps[K, V, VectorMap, VectorMap[K, V]] + with MapFactoryDefaults[K, V, VectorMap, Iterable] { + + import VectorMap._ + + override protected[this] def className: String = "VectorMap" + + private[immutable] def this(fields: Vector[K], underlying: Map[K, (Int, V)]) = { + this(fields, underlying, 0) + } + + override val size = underlying.size + + override def knownSize: Int = size + + override def isEmpty: Boolean = size == 0 + + def updated[V1 >: V](key: K, value: V1): VectorMap[K, V1] = { + underlying.get(key) match { + case Some((slot, _)) => + new VectorMap(fields, underlying.updated[(Int, V1)](key, (slot, value)), dropped) + case None => + new VectorMap(fields :+ key, underlying.updated[(Int, V1)](key, (fields.length + dropped, value)), dropped) + } + } + + override def withDefault[V1 >: V](d: K -> V1): Map[K, V1] = + new Map.WithDefault(this, d) + + override def withDefaultValue[V1 >: V](d: V1): Map[K, V1] = + new Map.WithDefault[K, V1](this, _ => d) + + def get(key: K): Option[V] = underlying.get(key) match { + case Some(v) => Some(v._2) + case None => None + } + + @tailrec + private def nextValidField(slot: Int): (Int, K) = { + if (slot >= fields.size) (-1, null.asInstanceOf[K]) + else fields(slot) match { + case Tombstone(distance) => + nextValidField(slot + distance) + case k => + (slot, k.asInstanceOf[K]) + } + } + + def iterator: Iterator[(K, V)] = new AbstractIterator[(K, V)] { + private[this] val fieldsLength = fields.length + private[this] var slot = -1 + private[this] var key: K = null.asInstanceOf[K] + + private[this] def advance(): Unit = { + val nextSlot = slot + 1 + if (nextSlot >= fieldsLength) { + slot = fieldsLength + key = null.asInstanceOf[K] + } else { + nextValidField(nextSlot) match { + case (-1, _) => + slot = fieldsLength + key = null.asInstanceOf[K] + case (s, k) => + slot = s + key = k + } + } + } + + advance() + + override def hasNext: Boolean = slot < fieldsLength + + override def next(): (K, V) = { + if (!hasNext) throw new NoSuchElementException("next called on depleted iterator") + val result = (key, underlying(key)._2) + advance() + result + } + } + + // No-Op overrides to allow for more efficient steppers in a minor release. + // Refining the return type to `S with EfficientSplit` is binary compatible. + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[(K, V), S]): S = super.stepper(shape) + + override def keyStepper[S <: Stepper[_]](implicit shape: StepperShape[K, S]): S = super.keyStepper(shape) + + override def valueStepper[S <: Stepper[_]](implicit shape: StepperShape[V, S]): S = super.valueStepper(shape) + + + def removed(key: K): VectorMap[K, V] = { + if (isEmpty) empty + else { + var fs = fields + val sz = fs.size + underlying.get(key) match { + case Some(_) if size == 1 => empty + case Some((slot, _)) => + val s = slot - dropped + + // Calculate next of kin + val next = + if (s < sz - 1) fs(s + 1) match { + case Tombstone(d) => s + d + 1 + case _ => s + 1 + } else s + 1 + + fs = fs.updated(s, Tombstone(next - s)) + + // Calculate first index of preceding tombstone sequence + val first = + if (s > 0) { + fs(s - 1) match { + case Tombstone(d) if d < 0 => if (s + d >= 0) s + d else 0 + case Tombstone(d) if d == 1 => s - 1 + case Tombstone(d) => throw new IllegalStateException("tombstone indicate wrong position: " + d) + case _ => s + } + }else s + fs = fs.updated(first, Tombstone(next - first)) + + // Calculate last index of succeeding tombstone sequence + val last = next - 1 + if (last != first) { + fs = fs.updated(last, Tombstone(first - 1 - last)) + } + new VectorMap(fs, underlying - key, dropped) + case _ => + this + } + } + } + + override def mapFactory: MapFactory[VectorMap] = VectorMap + + override def contains(key: K): Boolean = underlying.contains(key) + + override def head: (K, V) = iterator.next() + + override def last: (K, V) = { + if (isEmpty) throw new UnsupportedOperationException("empty.last") + val lastSlot = fields.length - 1 + val last = fields.last match { + case Tombstone(d) if d < 0 => fields(lastSlot + d).asInstanceOf[K] + case Tombstone(d) if d == 1 => fields(lastSlot - 1).asInstanceOf[K] + case Tombstone(d) => throw new IllegalStateException("tombstone indicate wrong position: " + d) + case k => k.asInstanceOf[K] + } + (last, underlying(last)._2) + } + + override def lastOption: Option[(K, V)] = { + if (isEmpty) None + else Some(last) + } + + override def tail: VectorMap[K, V] = { + if (isEmpty) throw new UnsupportedOperationException("empty.tail") + val (slot, key) = nextValidField(0) + new VectorMap(fields.drop(slot + 1), underlying - key, dropped + slot + 1) + } + + override def init: VectorMap[K, V] = { + if (isEmpty) throw new UnsupportedOperationException("empty.init") + val lastSlot = fields.size - 1 + val (slot, key) = fields.last match { + case Tombstone(d) if d < 0 => (lastSlot + d, fields(lastSlot + d).asInstanceOf[K]) + case Tombstone(d) if d == 1 => (lastSlot - 1, fields(lastSlot - 1).asInstanceOf[K]) + case Tombstone(d) => throw new IllegalStateException("tombstone indicate wrong position: " + d) + case k => (lastSlot, k.asInstanceOf[K]) + } + new VectorMap(fields.dropRight(fields.size - slot), underlying - key, dropped) + } + + override def keys: Vector[K] = keysIterator.toVector + + override def values: Iterable[V] = new Iterable[V] with IterableFactoryDefaults[V, Iterable] { + override def iterator: Iterator[V] = keysIterator.map(underlying(_)._2) + } +} + +object VectorMap extends MapFactory[VectorMap] { + //Class to mark deleted slots in 'fields'. + //When one or more consecutive slots are deleted, the 'distance' of the first 'Tombstone' + // represents the distance to the location of the next undeleted slot (or the last slot in 'fields' +1 if it does not exist). + //When two or more consecutive slots are deleted, the 'distance' of the trailing 'Tombstone' + // represents the distance to the location of the previous undeleted slot ( or -1 if it does not exist) multiplied by -1. + //For other deleted slots, it simply indicates that they have been deleted. + private[VectorMap] final case class Tombstone(distance: Int) + + private[this] final val EmptyMap: VectorMap[Nothing, Nothing] = + new VectorMap[Nothing, Nothing](Vector.empty[Nothing], HashMap.empty[Nothing, (Int, Nothing)]) + + def empty[K, V]: VectorMap[K, V] = EmptyMap.asInstanceOf[VectorMap[K, V]] + + def from[K, V](it: collection.IterableOnce[(K, V)]^): VectorMap[K, V] = + it match { + case vm: VectorMap[K, V] => vm + case _ => (newBuilder[K, V] ++= it).result() + } + + def newBuilder[K, V]: mutable.Builder[(K, V), VectorMap[K, V]] = new VectorMapBuilder[K, V] +} + +private[immutable] final class VectorMapBuilder[K, V] extends mutable.Builder[(K, V), VectorMap[K, V]] { + private[this] val vectorBuilder = new VectorBuilder[K] + private[this] val mapBuilder = new MapBuilderImpl[K, (Int, V)] + private[this] var aliased: VectorMap[K, V] @uncheckedCaptures = _ // OK since VectorMapBuilder is private + + override def clear(): Unit = { + vectorBuilder.clear() + mapBuilder.clear() + aliased = null + } + + override def result(): VectorMap[K, V] = { + if (aliased eq null) { + aliased = new VectorMap(vectorBuilder.result(), mapBuilder.result()) + } + aliased + } + def addOne(key: K, value: V): this.type = { + if (aliased ne null) { + aliased = aliased.updated(key, value) + } else { + mapBuilder.getOrElse(key, null) match { + case (slot, _) => + mapBuilder.addOne(key, (slot, value)) + case null => + val vectorSize = vectorBuilder.size + vectorBuilder.addOne(key) + mapBuilder.addOne(key, (vectorSize, value)) + } + } + this + } + + override def addOne(elem: (K, V)): this.type = addOne(elem._1, elem._2) +} From eea6bca2861eee47b68e02fe17b6d09508a6ba57 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 17:33:44 +0100 Subject: [PATCH 75/89] Add immutable TreeSet and TreeMap to stdlib --- .../stdlib/collection/BuildFrom.scala | 2 +- .../stdlib/collection/immutable/TreeMap.scala | 372 ++++++++++++++++++ .../stdlib/collection/immutable/TreeSet.scala | 297 ++++++++++++++ .../collection/immutable/WrappedString.scala | 142 +++++++ .../stdlib/collection/immutable/package.scala | 29 ++ 5 files changed, 841 insertions(+), 1 deletion(-) create mode 100644 tests/pos-special/stdlib/collection/immutable/TreeMap.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/TreeSet.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/WrappedString.scala create mode 100644 tests/pos-special/stdlib/collection/immutable/package.scala diff --git a/tests/pos-special/stdlib/collection/BuildFrom.scala b/tests/pos-special/stdlib/collection/BuildFrom.scala index 15a8acf2e6ef..0a3cc199d4dc 100644 --- a/tests/pos-special/stdlib/collection/BuildFrom.scala +++ b/tests/pos-special/stdlib/collection/BuildFrom.scala @@ -31,7 +31,7 @@ trait BuildFrom[-From, -A, +C] extends Any { self => def fromSpecific(from: From)(it: IterableOnce[A]^): C // !!! this is wrong, we need two versions of fromSpecific; one mapping // to C^{it} when C is an Iterable, and one mapping to C when C is a Seq, Map, or Set. - // But that requires a lareg scale refactoring of BuildFrom. The unsafeAssumePure + // But that requires a large scale refactoring of BuildFrom. The unsafeAssumePure // calls in this file are needed to sweep that problem under the carpet. /** Get a Builder for the collection. For non-strict collection types this will use an intermediate buffer. diff --git a/tests/pos-special/stdlib/collection/immutable/TreeMap.scala b/tests/pos-special/stdlib/collection/immutable/TreeMap.scala new file mode 100644 index 000000000000..ff01ad7806ec --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/TreeMap.scala @@ -0,0 +1,372 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.tailrec +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.immutable.{RedBlackTree => RB} +import scala.collection.mutable.ReusableBuilder +import scala.runtime.AbstractFunction2 +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** An immutable SortedMap whose values are stored in a red-black tree. + * + * This class is optimal when range queries will be performed, + * or when traversal in order of an ordering is desired. + * If you only need key lookups, and don't care in which order key-values + * are traversed in, consider using * [[scala.collection.immutable.HashMap]], + * which will generally have better performance. If you need insertion order, + * consider a * [[scala.collection.immutable.SeqMap]], which does not need to + * have an ordering supplied. + * + * @example {{{ + * import scala.collection.immutable.TreeMap + * + * // Make a TreeMap via the companion object factory + * val weekdays = TreeMap( + * 2 -> "Monday", + * 3 -> "Tuesday", + * 4 -> "Wednesday", + * 5 -> "Thursday", + * 6 -> "Friday" + * ) + * // TreeMap(2 -> Monday, 3 -> Tuesday, 4 -> Wednesday, 5 -> Thursday, 6 -> Friday) + * + * val days = weekdays ++ List(1 -> "Sunday", 7 -> "Saturday") + * // TreeMap(1 -> Sunday, 2 -> Monday, 3 -> Tuesday, 4 -> Wednesday, 5 -> Thursday, 6 -> Friday, 7 -> Saturday) + * + * val day3 = days.get(3) // Some("Tuesday") + * + * val rangeOfDays = days.range(2, 5) // TreeMap(2 -> Monday, 3 -> Tuesday, 4 -> Wednesday) + * + * val daysUntil2 = days.rangeUntil(2) // TreeMap(1 -> Sunday) + * val daysTo2 = days.rangeTo(2) // TreeMap(1 -> Sunday, 2 -> Monday) + * val daysAfter5 = days.rangeFrom(5) // TreeMap(5 -> Thursday, 6 -> Friday, 7 -> Saturday) + * }}} + * + * @tparam K the type of the keys contained in this tree map. + * @tparam V the type of the values associated with the keys. + * @param ordering the implicit ordering used to compare objects of type `A`. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#red-black-trees "Scala's Collection Library overview"]] + * section on `Red-Black Trees` for more information. + * + * @define Coll immutable.TreeMap + * @define coll immutable tree map + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +final class TreeMap[K, +V] private (private val tree: RB.Tree[K, V])(implicit val ordering: Ordering[K]) + extends AbstractMap[K, V] + with SortedMap[K, V] + with StrictOptimizedSortedMapOps[K, V, TreeMap, TreeMap[K, V]] + with SortedMapFactoryDefaults[K, V, TreeMap, Iterable, Map] + with DefaultSerializable { + + def this()(implicit ordering: Ordering[K]) = this(null)(ordering) + private[immutable] def tree0: RB.Tree[K, V] = tree + + private[this] def newMapOrSelf[V1 >: V](t: RB.Tree[K, V1]): TreeMap[K, V1] = if(t eq tree) this else new TreeMap[K, V1](t) + + override def sortedMapFactory: SortedMapFactory[TreeMap] = TreeMap + + def iterator: Iterator[(K, V)] = RB.iterator(tree) + + def keysIteratorFrom(start: K): Iterator[K] = RB.keysIterator(tree, Some(start)) + + override def keySet: TreeSet[K] = new TreeSet(tree)(ordering) + + def iteratorFrom(start: K): Iterator[(K, V)] = RB.iterator(tree, Some(start)) + + override def valuesIteratorFrom(start: K): Iterator[V] = RB.valuesIterator(tree, Some(start)) + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[(K, V), S]): S with EfficientSplit = + shape.parUnbox( + scala.collection.convert.impl.AnyBinaryTreeStepper.from[(K, V), RB.Tree[K, V]]( + size, tree, _.left, _.right, x => (x.key, x.value) + ) + ) + + override def keyStepper[S <: Stepper[_]](implicit shape: StepperShape[K, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + type T = RB.Tree[K, V] + val s = shape.shape match { + case StepperShape.IntShape => IntBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.key.asInstanceOf[Int]) + case StepperShape.LongShape => LongBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.key.asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleBinaryTreeStepper.from[T](size, tree, _.left, _.right, _.key.asInstanceOf[Double]) + case _ => shape.parUnbox(AnyBinaryTreeStepper.from[K, T](size, tree, _.left, _.right, _.key)) + } + s.asInstanceOf[S with EfficientSplit] + } + + override def valueStepper[S <: Stepper[_]](implicit shape: StepperShape[V, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + type T = RB.Tree[K, V] + val s = shape.shape match { + case StepperShape.IntShape => IntBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.value.asInstanceOf[Int]) + case StepperShape.LongShape => LongBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.value.asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.value.asInstanceOf[Double]) + case _ => shape.parUnbox(AnyBinaryTreeStepper.from[V, T] (size, tree, _.left, _.right, _.value.asInstanceOf[V])) + } + s.asInstanceOf[S with EfficientSplit] + } + + def get(key: K): Option[V] = RB.get(tree, key) + override def getOrElse[V1 >: V](key: K, default: => V1): V1 = { + val resultOrNull = RB.lookup(tree, key) + if (resultOrNull eq null) default + else resultOrNull.value + } + + def removed(key: K): TreeMap[K,V] = + newMapOrSelf(RB.delete(tree, key)) + + def updated[V1 >: V](key: K, value: V1): TreeMap[K, V1] = + newMapOrSelf(RB.update(tree, key, value, overwrite = true)) + + override def concat[V1 >: V](that: collection.IterableOnce[(K, V1)]^): TreeMap[K, V1] = + newMapOrSelf(that match { + case tm: TreeMap[K, V] @unchecked if ordering == tm.ordering => + RB.union(tree, tm.tree) + case ls: LinearSeq[(K,V1)] => + if (ls.isEmpty) tree //to avoid the creation of the adder + else { + val adder = new Adder[V1] + adder.addAll(ls) + adder.finalTree + } + case _ => + val adder = new Adder[V1] + val it = that.iterator + while (it.hasNext) { + adder.apply(it.next()) + } + adder.finalTree + }) + + override def removedAll(keys: IterableOnce[K]^): TreeMap[K, V] = keys match { + case ts: TreeSet[K] if ordering == ts.ordering => + newMapOrSelf(RB.difference(tree, ts.tree)) + case _ => super.removedAll(keys) + } + + /** A new TreeMap with the entry added is returned, + * assuming that key is not in the TreeMap. + * + * @tparam V1 type of the values of the new bindings, a supertype of `V` + * @param key the key to be inserted + * @param value the value to be associated with `key` + * @return a new $coll with the inserted binding, if it wasn't present in the map + */ + @deprecated("Use `updated` instead", "2.13.0") + def insert[V1 >: V](key: K, value: V1): TreeMap[K, V1] = { + assert(!RB.contains(tree, key)) + updated(key, value) + } + + def rangeImpl(from: Option[K], until: Option[K]): TreeMap[K, V] = newMapOrSelf(RB.rangeImpl(tree, from, until)) + + override def minAfter(key: K): Option[(K, V)] = RB.minAfter(tree, key) match { + case null => Option.empty + case x => Some((x.key, x.value)) + } + + override def maxBefore(key: K): Option[(K, V)] = RB.maxBefore(tree, key) match { + case null => Option.empty + case x => Some((x.key, x.value)) + } + + override def range(from: K, until: K): TreeMap[K,V] = newMapOrSelf(RB.range(tree, from, until)) + + override def foreach[U](f: ((K, V)) => U): Unit = RB.foreach(tree, f) + override def foreachEntry[U](f: (K, V) => U): Unit = RB.foreachEntry(tree, f) + override def size: Int = RB.count(tree) + override def knownSize: Int = size + + override def isEmpty = size == 0 + + override def firstKey: K = RB.smallest(tree).key + + override def lastKey: K = RB.greatest(tree).key + + override def head: (K, V) = { + val smallest = RB.smallest(tree) + (smallest.key, smallest.value) + } + + override def last: (K, V) = { + val greatest = RB.greatest(tree) + (greatest.key, greatest.value) + } + + override def tail: TreeMap[K, V] = new TreeMap(RB.tail(tree)) + + override def init: TreeMap[K, V] = new TreeMap(RB.init(tree)) + + override def drop(n: Int): TreeMap[K, V] = { + if (n <= 0) this + else if (n >= size) empty + else new TreeMap(RB.drop(tree, n)) + } + + override def take(n: Int): TreeMap[K, V] = { + if (n <= 0) empty + else if (n >= size) this + else new TreeMap(RB.take(tree, n)) + } + + override def slice(from: Int, until: Int) = { + if (until <= from) empty + else if (from <= 0) take(until) + else if (until >= size) drop(from) + else new TreeMap(RB.slice(tree, from, until)) + } + + override def dropRight(n: Int): TreeMap[K, V] = take(size - math.max(n, 0)) + + override def takeRight(n: Int): TreeMap[K, V] = drop(size - math.max(n, 0)) + + private[this] def countWhile(p: ((K, V)) => Boolean): Int = { + var result = 0 + val it = iterator + while (it.hasNext && p(it.next())) result += 1 + result + } + + override def dropWhile(p: ((K, V)) => Boolean): TreeMap[K, V] = drop(countWhile(p)) + + override def takeWhile(p: ((K, V)) => Boolean): TreeMap[K, V] = take(countWhile(p)) + + override def span(p: ((K, V)) => Boolean): (TreeMap[K, V], TreeMap[K, V]) = splitAt(countWhile(p)) + + override def filter(f: ((K, V)) => Boolean): TreeMap[K, V] = + newMapOrSelf(RB.filterEntries[K, V](tree, (k, v) => f((k, v)))) + + override def partition(p: ((K, V)) => Boolean): (TreeMap[K, V], TreeMap[K, V]) = { + val (l, r) = RB.partitionEntries[K, V](tree, (k, v) => p((k, v))) + (newMapOrSelf(l), newMapOrSelf(r)) + } + + override def transform[W](f: (K, V) => W): TreeMap[K, W] = { + val t2 = RB.transform[K, V, W](tree, f) + if(t2 eq tree) this.asInstanceOf[TreeMap[K, W]] + else new TreeMap(t2) + } + + private final class Adder[B1 >: V] + extends RB.MapHelper[K, B1] with Function1[(K, B1), Unit] { + private var currentMutableTree: RB.Tree[K,B1] @uncheckedCaptures = tree0 + def finalTree = beforePublish(currentMutableTree) + override def apply(kv: (K, B1)): Unit = { + currentMutableTree = mutableUpd(currentMutableTree, kv._1, kv._2) + } + @tailrec def addAll(ls: LinearSeq[(K, B1)]): Unit = { + if (!ls.isEmpty) { + val kv = ls.head + currentMutableTree = mutableUpd(currentMutableTree, kv._1, kv._2) + addAll(ls.tail) + } + } + } + override def equals(obj: Any): Boolean = obj match { + case that: TreeMap[K @unchecked, _] if ordering == that.ordering => RB.entriesEqual(tree, that.tree) + case _ => super.equals(obj) + } + + override protected[this] def className = "TreeMap" +} + +/** $factoryInfo + * @define Coll immutable.TreeMap + * @define coll immutable tree map + */ +@SerialVersionUID(3L) +object TreeMap extends SortedMapFactory[TreeMap] { + + def empty[K : Ordering, V]: TreeMap[K, V] = new TreeMap() + + def from[K, V](it: IterableOnce[(K, V)]^)(implicit ordering: Ordering[K]): TreeMap[K, V] = + it match { + case tm: TreeMap[K, V] if ordering == tm.ordering => tm + case sm: scala.collection.SortedMap[K, V] if ordering == sm.ordering => + new TreeMap[K, V](RB.fromOrderedEntries(sm.iterator, sm.size)) + case _ => + var t: RB.Tree[K, V] = null + val i = it.iterator + while (i.hasNext) { + val (k, v) = i.next() + t = RB.update(t, k, v, overwrite = true) + } + new TreeMap[K, V](t) + } + + def newBuilder[K, V](implicit ordering: Ordering[K]): ReusableBuilder[(K, V), TreeMap[K, V]] = new TreeMapBuilder[K, V] + + private class TreeMapBuilder[K, V](implicit ordering: Ordering[K]) + extends RB.MapHelper[K, V] + with ReusableBuilder[(K, V), TreeMap[K, V]] { + type Tree = RB.Tree[K, V] + private var tree:Tree @uncheckedCaptures = null + + def addOne(elem: (K, V)): this.type = { + tree = mutableUpd(tree, elem._1, elem._2) + this + } + private object adder extends AbstractFunction2[K, V, Unit] { + // we cache tree to avoid the outer access to tree + // in the hot path (apply) + private[this] var accumulator: Tree @uncheckedCaptures = null + def addForEach(hasForEach: collection.Map[K, V]): Unit = { + accumulator = tree + hasForEach.foreachEntry(this) + tree = accumulator + // be friendly to GC + accumulator = null + } + + override def apply(key: K, value: V): Unit = { + accumulator = mutableUpd(accumulator, key, value) + } + } + + override def addAll(xs: IterableOnce[(K, V)]^): this.type = { + xs match { + // TODO consider writing a mutable-safe union for TreeSet/TreeMap builder ++= + // for the moment we have to force immutability before the union + // which will waste some time and space + // calling `beforePublish` makes `tree` immutable + case ts: TreeMap[K, V] if ts.ordering == ordering => + if (tree eq null) tree = ts.tree0 + else tree = RB.union(beforePublish(tree), ts.tree0) + case that: collection.Map[K, V] => + //add avoiding creation of tuples + adder.addForEach(that) + case _ => + super.addAll(xs) + } + this + } + + override def clear(): Unit = { + tree = null + } + + override def result(): TreeMap[K, V] = new TreeMap[K, V](beforePublish(tree)) + } +} diff --git a/tests/pos-special/stdlib/collection/immutable/TreeSet.scala b/tests/pos-special/stdlib/collection/immutable/TreeSet.scala new file mode 100644 index 000000000000..c4241b818c38 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/TreeSet.scala @@ -0,0 +1,297 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.collection.Stepper.EfficientSplit +import scala.collection.generic.DefaultSerializable +import scala.collection.mutable.ReusableBuilder +import scala.collection.immutable.{RedBlackTree => RB} +import scala.runtime.AbstractFunction1 +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** This class implements immutable sorted sets using a tree. + * + * @tparam A the type of the elements contained in this tree set + * @param ordering the implicit ordering used to compare objects of type `A` + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#red-black-trees "Scala's Collection Library overview"]] + * section on `Red-Black Trees` for more information. + * + * @define Coll `immutable.TreeSet` + * @define coll immutable tree set + * @define orderDependent + * @define orderDependentFold + * @define mayNotTerminateInf + * @define willNotTerminateInf + */ +final class TreeSet[A] private[immutable] (private[immutable] val tree: RB.Tree[A, Any])(implicit val ordering: Ordering[A]) + extends AbstractSet[A] + with SortedSet[A] + with SortedSetOps[A, TreeSet, TreeSet[A]] + with StrictOptimizedSortedSetOps[A, TreeSet, TreeSet[A]] + with SortedSetFactoryDefaults[A, TreeSet, Set] + with DefaultSerializable { + + if (ordering eq null) throw new NullPointerException("ordering must not be null") + + def this()(implicit ordering: Ordering[A]) = this(null)(ordering) + + override def sortedIterableFactory = TreeSet + + private[this] def newSetOrSelf(t: RB.Tree[A, Any]) = if(t eq tree) this else new TreeSet[A](t) + + override def size: Int = RB.count(tree) + + override def isEmpty = size == 0 + + override def head: A = RB.smallest(tree).key + + override def last: A = RB.greatest(tree).key + + override def tail: TreeSet[A] = new TreeSet(RB.tail(tree)) + + override def init: TreeSet[A] = new TreeSet(RB.init(tree)) + + override def min[A1 >: A](implicit ord: Ordering[A1]): A = { + if ((ord eq ordering) && nonEmpty) { + head + } else { + super.min(ord) + } + } + + override def max[A1 >: A](implicit ord: Ordering[A1]): A = { + if ((ord eq ordering) && nonEmpty) { + last + } else { + super.max(ord) + } + } + + override def drop(n: Int): TreeSet[A] = { + if (n <= 0) this + else if (n >= size) empty + else new TreeSet(RB.drop(tree, n)) + } + + override def take(n: Int): TreeSet[A] = { + if (n <= 0) empty + else if (n >= size) this + else new TreeSet(RB.take(tree, n)) + } + + override def slice(from: Int, until: Int): TreeSet[A] = { + if (until <= from) empty + else if (from <= 0) take(until) + else if (until >= size) drop(from) + else new TreeSet(RB.slice(tree, from, until)) + } + + override def dropRight(n: Int): TreeSet[A] = take(size - math.max(n, 0)) + + override def takeRight(n: Int): TreeSet[A] = drop(size - math.max(n, 0)) + + private[this] def countWhile(p: A => Boolean): Int = { + var result = 0 + val it = iterator + while (it.hasNext && p(it.next())) result += 1 + result + } + override def dropWhile(p: A => Boolean): TreeSet[A] = drop(countWhile(p)) + + override def takeWhile(p: A => Boolean): TreeSet[A] = take(countWhile(p)) + + override def span(p: A => Boolean): (TreeSet[A], TreeSet[A]) = splitAt(countWhile(p)) + + override def foreach[U](f: A => U): Unit = RB.foreachKey(tree, f) + + override def minAfter(key: A): Option[A] = { + val v = RB.minAfter(tree, key) + if (v eq null) Option.empty else Some(v.key) + } + + override def maxBefore(key: A): Option[A] = { + val v = RB.maxBefore(tree, key) + if (v eq null) Option.empty else Some(v.key) + } + + def iterator: Iterator[A] = RB.keysIterator(tree) + + def iteratorFrom(start: A): Iterator[A] = RB.keysIterator(tree, Some(start)) + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S with EfficientSplit = { + import scala.collection.convert.impl._ + type T = RB.Tree[A, Any] + val s = shape.shape match { + case StepperShape.IntShape => IntBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.key.asInstanceOf[Int]) + case StepperShape.LongShape => LongBinaryTreeStepper.from[T] (size, tree, _.left, _.right, _.key.asInstanceOf[Long]) + case StepperShape.DoubleShape => DoubleBinaryTreeStepper.from[T](size, tree, _.left, _.right, _.key.asInstanceOf[Double]) + case _ => shape.parUnbox(AnyBinaryTreeStepper.from[A, T](size, tree, _.left, _.right, _.key)) + } + s.asInstanceOf[S with EfficientSplit] + } + + /** Checks if this set contains element `elem`. + * + * @param elem the element to check for membership. + * @return true, iff `elem` is contained in this set. + */ + def contains(elem: A): Boolean = RB.contains(tree, elem) + + override def range(from: A, until: A): TreeSet[A] = newSetOrSelf(RB.range(tree, from, until)) + + def rangeImpl(from: Option[A], until: Option[A]): TreeSet[A] = newSetOrSelf(RB.rangeImpl(tree, from, until)) + + /** Creates a new `TreeSet` with the entry added. + * + * @param elem a new element to add. + * @return a new $coll containing `elem` and all the elements of this $coll. + */ + def incl(elem: A): TreeSet[A] = + newSetOrSelf(RB.update(tree, elem, null, overwrite = false)) + + /** Creates a new `TreeSet` with the entry removed. + * + * @param elem a new element to add. + * @return a new $coll containing all the elements of this $coll except `elem`. + */ + def excl(elem: A): TreeSet[A] = + newSetOrSelf(RB.delete(tree, elem)) + + override def concat(that: collection.IterableOnce[A]): TreeSet[A] = { + val t = that match { + case ts: TreeSet[A] if ordering == ts.ordering => + RB.union(tree, ts.tree) + case _ => + val it = that.iterator + var t = tree + while (it.hasNext) t = RB.update(t, it.next(), null, overwrite = false) + t + } + newSetOrSelf(t) + } + + override def removedAll(that: IterableOnce[A]): TreeSet[A] = that match { + case ts: TreeSet[A] if ordering == ts.ordering => + newSetOrSelf(RB.difference(tree, ts.tree)) + case _ => + //TODO add an implementation of a mutable subtractor similar to TreeMap + //but at least this doesn't create a TreeSet for each iteration + object sub extends AbstractFunction1[A, Unit] { + var currentTree = tree + override def apply(k: A): Unit = { + currentTree = RB.delete(currentTree, k) + } + } + that.iterator.foreach(sub) + newSetOrSelf(sub.currentTree) + } + + override def intersect(that: collection.Set[A]): TreeSet[A] = that match { + case ts: TreeSet[A] if ordering == ts.ordering => + newSetOrSelf(RB.intersect(tree, ts.tree)) + case _ => + super.intersect(that) + } + + override def diff(that: collection.Set[A]): TreeSet[A] = that match { + case ts: TreeSet[A] if ordering == ts.ordering => + newSetOrSelf(RB.difference(tree, ts.tree)) + case _ => + super.diff(that) + } + + override def filter(f: A => Boolean): TreeSet[A] = newSetOrSelf(RB.filterEntries[A, Any](tree, {(k, _) => f(k)})) + + override def partition(p: A => Boolean): (TreeSet[A], TreeSet[A]) = { + val (l, r) = RB.partitionEntries(tree, {(a:A, _: Any) => p(a)}) + (newSetOrSelf(l), newSetOrSelf(r)) + } + + override def equals(obj: Any): Boolean = obj match { + case that: TreeSet[A @unchecked] if ordering == that.ordering => RB.keysEqual(tree, that.tree) + case _ => super.equals(obj) + } + + override protected[this] def className = "TreeSet" +} + +/** + * $factoryInfo + * + * @define Coll `immutable.TreeSet` + * @define coll immutable tree set + */ +@SerialVersionUID(3L) +object TreeSet extends SortedIterableFactory[TreeSet] { + + def empty[A: Ordering]: TreeSet[A] = new TreeSet[A] + + def from[E](it: scala.collection.IterableOnce[E]^)(implicit ordering: Ordering[E]): TreeSet[E] = + it match { + case ts: TreeSet[E] if ordering == ts.ordering => ts + case ss: scala.collection.SortedSet[E] if ordering == ss.ordering => + new TreeSet[E](RB.fromOrderedKeys(ss.iterator, ss.size)) + case r: Range if (ordering eq Ordering.Int) || (Ordering.Int isReverseOf ordering) => + val it = if((ordering eq Ordering.Int) == (r.step > 0)) r.iterator else r.reverseIterator + val tree = RB.fromOrderedKeys(it.asInstanceOf[Iterator[E]], r.size) + // The cast is needed to compile with Dotty: + // Dotty doesn't infer that E =:= Int, since instantiation of covariant GADTs is unsound + new TreeSet[E](tree) + case _ => + var t: RB.Tree[E, Null] = null + val i = it.iterator + while (i.hasNext) t = RB.update(t, i.next(), null, overwrite = false) + new TreeSet[E](t) + } + + def newBuilder[A](implicit ordering: Ordering[A]): ReusableBuilder[A, TreeSet[A]] = new TreeSetBuilder[A] + private class TreeSetBuilder[A](implicit ordering: Ordering[A]) + extends RB.SetHelper[A] + with ReusableBuilder[A, TreeSet[A]] { + type Tree = RB.Tree[A, Any] + private [this] var tree:RB.Tree[A @uncheckedCaptures, Any] = null + + override def addOne(elem: A): this.type = { + tree = mutableUpd(tree, elem) + this + } + + override def addAll(xs: IterableOnce[A]^): this.type = { + xs match { + // TODO consider writing a mutable-safe union for TreeSet/TreeMap builder ++= + // for the moment we have to force immutability before the union + // which will waste some time and space + // calling `beforePublish` makes `tree` immutable + case ts: TreeSet[A] if ts.ordering == ordering => + if (tree eq null) tree = ts.tree + else tree = RB.union(beforePublish(tree), ts.tree)(ordering) + case ts: TreeMap[A @unchecked, _] if ts.ordering == ordering => + if (tree eq null) tree = ts.tree0 + else tree = RB.union(beforePublish(tree), ts.tree0)(ordering) + case _ => + super.addAll(xs) + } + this + } + + override def clear(): Unit = { + tree = null + } + + override def result(): TreeSet[A] = new TreeSet[A](beforePublish(tree))(ordering) + } +} diff --git a/tests/pos-special/stdlib/collection/immutable/WrappedString.scala b/tests/pos-special/stdlib/collection/immutable/WrappedString.scala new file mode 100644 index 000000000000..47fe769c81ef --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/WrappedString.scala @@ -0,0 +1,142 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package immutable + +import scala.Predef.{wrapString => _, assert} +import scala.collection.Stepper.EfficientSplit +import scala.collection.convert.impl.CharStringStepper +import scala.collection.mutable.{Builder, StringBuilder} +import language.experimental.captureChecking + +/** + * This class serves as a wrapper augmenting `String`s with all the operations + * found in indexed sequences. + * + * The difference between this class and `StringOps` is that calling transformer + * methods such as `filter` and `map` will yield an object of type `WrappedString` + * rather than a `String`. + * + * @param self a string contained within this wrapped string + * + * @define Coll `WrappedString` + * @define coll wrapped string + */ +@SerialVersionUID(3L) +final class WrappedString(private val self: String) extends AbstractSeq[Char] with IndexedSeq[Char] + with IndexedSeqOps[Char, IndexedSeq, WrappedString] + with Serializable + with Pure { + + def apply(i: Int): Char = self.charAt(i) + + override protected def fromSpecific(coll: scala.collection.IterableOnce[Char]^): WrappedString = WrappedString.fromSpecific(coll) + override protected def newSpecificBuilder: Builder[Char, WrappedString] = WrappedString.newBuilder + override def empty: WrappedString = WrappedString.empty + + override def slice(from: Int, until: Int): WrappedString = { + val start = if (from < 0) 0 else from + if (until <= start || start >= self.length) + return WrappedString.empty + + val end = if (until > length) length else until + new WrappedString(self.substring(start, end)) + } + override def length = self.length + override def toString = self + override def view: StringView = new StringView(self) + + override def stepper[S <: Stepper[_]](implicit shape: StepperShape[Char, S]): S with EfficientSplit = { + val st = new CharStringStepper(self, 0, self.length) + val r = + if (shape.shape == StepperShape.CharShape) st + else { + assert(shape.shape == StepperShape.ReferenceShape, s"unexpected StepperShape: $shape") + AnyStepper.ofParIntStepper(st) + } + r.asInstanceOf[S with EfficientSplit] + } + + override def startsWith[B >: Char](that: IterableOnce[B]^, offset: Int = 0): Boolean = + that match { + case s: WrappedString => self.startsWith(s.self, offset) + case _ => super.startsWith(that, offset) + } + + override def endsWith[B >: Char](that: collection.Iterable[B]^): Boolean = + that match { + case s: WrappedString => self.endsWith(s.self) + case _ => super.endsWith(that) + } + + override def indexOf[B >: Char](elem: B, from: Int = 0): Int = elem match { + case c: Char => self.indexOf(c, from) + case _ => super.indexOf(elem, from) + } + + override def lastIndexOf[B >: Char](elem: B, end: Int = length - 1): Int = + elem match { + case c: Char => self.lastIndexOf(c, end) + case _ => super.lastIndexOf(elem, end) + } + + override def copyToArray[sealed B >: Char](xs: Array[B], start: Int, len: Int): Int = + (xs: Any) match { + case chs: Array[Char] => + val copied = IterableOnce.elemsToCopyToArray(length, chs.length, start, len) + self.getChars(0, copied, chs, start) + copied + case _ => super.copyToArray(xs, start, len) + } + + override def appendedAll[B >: Char](suffix: IterableOnce[B]^): IndexedSeq[B] = + suffix match { + case s: WrappedString => new WrappedString(self concat s.self) + case _ => super.appendedAll(suffix) + } + + override def sameElements[B >: Char](o: IterableOnce[B]^) = o match { + case s: WrappedString => self == s.self + case _ => super.sameElements(o) + } + + override protected[this] def className = "WrappedString" + + override protected final def applyPreferredMaxLength: Int = Int.MaxValue + override def equals(other: Any): Boolean = other match { + case that: WrappedString => + this.self == that.self + case _ => + super.equals(other) + } +} + +/** A companion object for wrapped strings. + */ +@SerialVersionUID(3L) +object WrappedString extends SpecificIterableFactory[Char, WrappedString] { + def fromSpecific(it: IterableOnce[Char]^): WrappedString = { + val b = newBuilder + val s = it.knownSize + if(s >= 0) b.sizeHint(s) + b ++= it + b.result() + } + val empty: WrappedString = new WrappedString("") + def newBuilder: Builder[Char, WrappedString] = + new StringBuilder().mapResult(x => new WrappedString(x)) + + implicit class UnwrapOp(private val value: WrappedString) extends AnyVal { + def unwrap: String = value.self + } +} diff --git a/tests/pos-special/stdlib/collection/immutable/package.scala b/tests/pos-special/stdlib/collection/immutable/package.scala new file mode 100644 index 000000000000..985ef22859be --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/package.scala @@ -0,0 +1,29 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +import language.experimental.captureChecking + +package object immutable { + type StringOps = scala.collection.StringOps + val StringOps = scala.collection.StringOps + type StringView = scala.collection.StringView + val StringView = scala.collection.StringView + + @deprecated("Use Iterable instead of Traversable", "2.13.0") + type Traversable[+X] = Iterable[X] + @deprecated("Use Iterable instead of Traversable", "2.13.0") + val Traversable = Iterable + + @deprecated("Use Map instead of DefaultMap", "2.13.0") + type DefaultMap[K, +V] = scala.collection.immutable.Map[K, V] +} From 4625afc776dd8eaba3904b4bcaa090b2be18ab1f Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 18:01:38 +0100 Subject: [PATCH 76/89] Add immutable TreeSeqMap to stdlib --- .../collection/immutable/TreeSeqMap.scala | 651 ++++++++++++++++++ 1 file changed, 651 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala diff --git a/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala b/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala new file mode 100644 index 000000000000..d7cceb54cca3 --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala @@ -0,0 +1,651 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import scala.annotation.tailrec +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** This class implements an immutable map that preserves order using + * a hash map for the key to value mapping to provide efficient lookup, + * and a tree for the ordering of the keys to provide efficient + * insertion/modification order traversal and destructuring. + * + * By default insertion order (`TreeSeqMap.OrderBy.Insertion`) + * is used, but modification order (`TreeSeqMap.OrderBy.Modification`) + * can be used instead if so specified at creation. + * + * The `orderingBy(orderBy: TreeSeqMap.OrderBy): TreeSeqMap[K, V]` method + * can be used to switch to the specified ordering for the returned map. + * + * A key can be manually refreshed (i.e. placed at the end) via the + * `refresh(key: K): TreeSeqMap[K, V]` method (regardless of the ordering in + * use). + * + * Internally, an ordinal counter is increased for each insertion/modification + * and then the current ordinal is used as key in the tree map. After 2^32^ + * insertions/modifications the entire map is copied (thus resetting the ordinal + * counter). + * + * @tparam K the type of the keys contained in this map. + * @tparam V the type of the values associated with the keys in this map. + * @define coll immutable tree seq map + * @define Coll `immutable.TreeSeqMap` + */ +final class TreeSeqMap[K, +V] private ( + private val ordering: TreeSeqMap.Ordering[K], + private val mapping: TreeSeqMap.Mapping[K, V], + private val ordinal: Int, + val orderedBy: TreeSeqMap.OrderBy) + extends AbstractMap[K, V] + with SeqMap[K, V] + with MapOps[K, V, TreeSeqMap, TreeSeqMap[K, V]] + with StrictOptimizedIterableOps[(K, V), Iterable, TreeSeqMap[K, V]] + with StrictOptimizedMapOps[K, V, TreeSeqMap, TreeSeqMap[K, V]] + with MapFactoryDefaults[K, V, TreeSeqMap, Iterable] { + + import TreeSeqMap._ + + override protected[this] def className: String = "TreeSeqMap" + + override def mapFactory: MapFactory[TreeSeqMap] = TreeSeqMap + + override val size = mapping.size + + override def knownSize: Int = size + + override def isEmpty = size == 0 + + /* + // This should have been overridden in 2.13.0 but wasn't so it will have to wait since it is not forwards compatible + // Now handled in inherited method from scala.collection.MapFactoryDefaults instead. + override def empty = TreeSeqMap.empty[K, V](orderedBy) + */ + + def orderingBy(orderBy: OrderBy): TreeSeqMap[K, V] = { + if (orderBy == this.orderedBy) this + else if (isEmpty) TreeSeqMap.empty(orderBy) + else new TreeSeqMap(ordering, mapping, ordinal, orderBy) + } + + def updated[V1 >: V](key: K, value: V1): TreeSeqMap[K, V1] = { + mapping.get(key) match { + case e if ordinal == -1 && (orderedBy == OrderBy.Modification || e.isEmpty) => + // Reinsert into fresh instance to restart ordinal counting, expensive but only done after 2^32 updates. + TreeSeqMap.empty[K, V1](orderedBy) ++ this + (key -> value) + case Some((o, _)) if orderedBy == OrderBy.Insertion => + new TreeSeqMap( + ordering.include(o, key), + mapping.updated[(Int, V1)](key, (o, value)), + ordinal, // Do not increment the ordinal since the key is already present, i.e. o <= ordinal. + orderedBy) + case Some((o, _)) => + val o1 = increment(ordinal) + new TreeSeqMap( + ordering.exclude(o).append(o1, key), + mapping.updated[(Int, V1)](key, (o1, value)), + o1, + orderedBy) + case None => + val o1 = increment(ordinal) + new TreeSeqMap( + ordering.append(o1, key), + mapping.updated[(Int, V1)](key, (o1, value)), + o1, + orderedBy) + } + } + + def removed(key: K): TreeSeqMap[K, V] = { + mapping.get(key) match { + case Some((o, _)) => + new TreeSeqMap( + ordering.exclude(o), + mapping.removed(key), + ordinal, + orderedBy) + case None => + this + } + } + + def refresh(key: K): TreeSeqMap[K, V] = { + mapping.get(key) match { + case Some((o, _)) => + val o1 = increment(ordinal) + new TreeSeqMap( + ordering.exclude(o).append(o1, key), + mapping, + o1, + orderedBy) + case None => + this + } + } + + def get(key: K): Option[V] = mapping.get(key).map(value) + + def iterator: Iterator[(K, V)] = new AbstractIterator[(K, V)] { + private[this] val iter = ordering.iterator + + override def hasNext: Boolean = iter.hasNext + + override def next(): (K, V) = binding(iter.next()) + } + + override def keysIterator: Iterator[K] = new AbstractIterator[K] { + private[this] val iter = ordering.iterator + + override def hasNext: Boolean = iter.hasNext + + override def next(): K = iter.next() + } + + override def valuesIterator: Iterator[V] = new AbstractIterator[V] { + private[this] val iter = ordering.iterator + + override def hasNext: Boolean = iter.hasNext + + override def next(): V = value(binding(iter.next())) + } + + override def contains(key: K): Boolean = mapping.contains(key) + + override def head: (K, V) = binding(ordering.head) + + override def headOption = ordering.headOption.map(binding) + + override def last: (K, V) = binding(ordering.last) + + override def lastOption: Option[(K, V)] = ordering.lastOption.map(binding) + + override def tail: TreeSeqMap[K, V] = { + val (head, tail) = ordering.headTail + new TreeSeqMap(tail, mapping.removed(head), ordinal, orderedBy) + } + + override def init: TreeSeqMap[K, V] = { + val (init, last) = ordering.initLast + new TreeSeqMap(init, mapping.removed(last), ordinal, orderedBy) + } + + override def slice(from: Int, until: Int): TreeSeqMap[K, V] = { + val sz = size + if (sz == 0 || from >= until) TreeSeqMap.empty[K, V](orderedBy) + else { + val sz = size + val f = if (from >= 0) from else 0 + val u = if (until <= sz) until else sz + val l = u - f + if (l <= 0) TreeSeqMap.empty[K, V](orderedBy) + else if (l > sz / 2) { + // Remove front and rear incrementally if majority of elements are to be kept + val (front, rest) = ordering.splitAt(f) + val (ong, rear) = rest.splitAt(l) + var mng = this.mapping + val frontIter = front.iterator + while (frontIter.hasNext) { + mng = mng - frontIter.next() + } + val rearIter = rear.iterator + while (rearIter.hasNext) { + mng = mng - rearIter.next() + } + new TreeSeqMap(ong, mng, ordinal, orderedBy) + } else { + // Populate with builder otherwise + val bdr = newBuilder[K @uncheckedCaptures, V @uncheckedCaptures](orderedBy) + val iter = ordering.iterator + var i = 0 + while (i < f) { + iter.next() + i += 1 + } + while (i < u) { + val k = iter.next() + bdr.addOne((k, mapping(k)._2)) + i += 1 + } + bdr.result() + } + } + } + + override def map[K2, V2](f: ((K, V)) => (K2, V2)): TreeSeqMap[K2, V2] = { + val bdr = newBuilder[K2 @uncheckedCaptures, V2 @uncheckedCaptures](orderedBy) + val iter = ordering.iterator + while (iter.hasNext) { + val k = iter.next() + val (_, v) = mapping(k) + val (k2, v2) = f((k, v)) + bdr.addOne((k2, v2)) + } + bdr.result() + } + + override def flatMap[K2, V2](f: ((K, V)) => IterableOnce[(K2, V2)]^): TreeSeqMap[K2, V2] = { + val bdr = newBuilder[K2 @uncheckedCaptures, V2 @uncheckedCaptures](orderedBy) + val iter = ordering.iterator + while (iter.hasNext) { + val k = iter.next() + val (_, v) = mapping(k) + val jter = f((k, v)).iterator + while (jter.hasNext) { + val (k2, v2) = jter.next() + bdr.addOne((k2, v2)) + } + } + bdr.result() + } + + override def collect[K2, V2](pf: PartialFunction[(K, V), (K2, V2)]): TreeSeqMap[K2, V2] = { + val bdr = newBuilder[K2 @uncheckedCaptures, V2 @uncheckedCaptures](orderedBy) + val iter = ordering.iterator + while (iter.hasNext) { + val k = iter.next() + val (_, v) = mapping(k) + pf.runWith({ case (k2, v2) => bdr.addOne((k2, v2)) })((k, v)) + } + bdr.result() + } + + override def concat[V2 >: V](suffix: IterableOnce[(K, V2)]^): TreeSeqMap[K, V2] = { + var ong: Ordering[K] = ordering + var mng: Mapping[K, V2] = mapping + var ord = increment(ordinal) + val iter = suffix.iterator + while (iter.hasNext) { + val (k, v2) = iter.next() + mng.get(k) match { + case Some((o, v)) => + if (orderedBy == OrderBy.Insertion && v != v2) mng = mng.updated(k, (o, v2)) + else if (orderedBy == OrderBy.Modification) { + mng = mng.updated(k, (ord, v2)) + ong = ong.exclude(o).append(ord, k) + ord = increment(ord) + } + case None => + mng = mng.updated(k, (ord, v2)) + ong = ong.append(ord, k) + ord = increment(ord) + } + } + new TreeSeqMap[K, V2](ong, mng, ord, orderedBy) + } + + @`inline` private[this] def value(p: (_, V)) = p._2 + @`inline` private[this] def binding(k: K) = mapping(k).copy(_1 = k) +} +object TreeSeqMap extends MapFactory[TreeSeqMap] { + sealed trait OrderBy + object OrderBy { + case object Insertion extends OrderBy + case object Modification extends OrderBy + } + + private val EmptyByInsertion = new TreeSeqMap[Nothing, Nothing](Ordering.empty, HashMap.empty, 0, OrderBy.Insertion) + private val EmptyByModification = new TreeSeqMap[Nothing, Nothing](Ordering.empty, HashMap.empty, 0, OrderBy.Modification) + val Empty = EmptyByInsertion + def empty[K, V]: TreeSeqMap[K, V] = empty(OrderBy.Insertion) + def empty[K, V](orderBy: OrderBy): TreeSeqMap[K, V] = { + if (orderBy == OrderBy.Modification) EmptyByModification + else EmptyByInsertion + }.asInstanceOf[TreeSeqMap[K, V]] + + def from[sealed K, sealed V](it: collection.IterableOnce[(K, V)]^): TreeSeqMap[K, V] = + it match { + case om: TreeSeqMap[K, V] => om + case _ => (newBuilder[K, V] ++= it).result() + } + + @inline private def increment(ord: Int) = if (ord == Int.MaxValue) Int.MinValue else ord + 1 + + def newBuilder[sealed K, sealed V]: mutable.Builder[(K, V), TreeSeqMap[K, V]] = newBuilder(OrderBy.Insertion) + def newBuilder[sealed K, sealed V](orderedBy: OrderBy): mutable.Builder[(K, V), TreeSeqMap[K, V]] = new Builder[K, V](orderedBy) + + final class Builder[sealed K, sealed V](orderedBy: OrderBy) extends mutable.Builder[(K, V), TreeSeqMap[K, V]] { + private[this] val bdr = new MapBuilderImpl[K, (Int, V)] + private[this] var ong = Ordering.empty[K] + private[this] var ord = 0 + private[this] var aliased: TreeSeqMap[K, V] = _ + + override def addOne(elem: (K, V)): this.type = addOne(elem._1, elem._2) + def addOne(key: K, value: V): this.type = { + if (aliased ne null) { + aliased = aliased.updated(key, value) + } else { + bdr.getOrElse(key, null) match { + case (o, v) => + if (orderedBy == OrderBy.Insertion && v != value) bdr.addOne(key, (o, value)) + else if (orderedBy == OrderBy.Modification) { + bdr.addOne(key, (ord, value)) + ong = ong.exclude(o).appendInPlace(ord, key) + ord = increment(ord) + } + case null => + bdr.addOne(key, (ord, value)) + ong = ong.appendInPlace(ord, key) + ord = increment(ord) + } + } + this + } + + override def clear(): Unit = { + ong = Ordering.empty + ord = 0 + bdr.clear() + aliased = null + } + + override def result(): TreeSeqMap[K, V] = { + if (aliased eq null) { + aliased = new TreeSeqMap(ong, bdr.result(), ord, orderedBy) + } + aliased + } + } + + private type Mapping[K, +V] = Map[K, (Int, V)] + @annotation.unused + private val Mapping = Map + + /* The ordering implementation below is an adapted version of immutable.IntMap. */ + private[immutable] object Ordering { + import scala.collection.generic.BitOperations.Int._ + + @inline private[immutable] def toBinaryString(i: Int): String = s"$i/${i.toBinaryString}" + + def empty[T] : Ordering[T] = Zero + + def apply[T](elems: (Int, T)*): Ordering[T] = + elems.foldLeft(empty[T])((x, y) => x.include(y._1, y._2)) + + // Iterator over a non-empty Ordering. + final class Iterator[+V](it: Ordering[V]) { + // Basically this uses a simple stack to emulate conversion over the tree. However + // because we know that Ints are at least 32 bits we can have at most 32 Bins and + // one Tip sitting on the tree at any point. Therefore we know the maximum stack + // depth is 33 + private[this] var index = 0 + private[this] val buffer = new Array[AnyRef](33) + + private[this] def pop = { + index -= 1 + buffer(index).asInstanceOf[Ordering[V]] + } + + private[this] def push[V2 >: V](x: Ordering[V2]): Unit = { + buffer(index) = x.asInstanceOf[AnyRef] + index += 1 + } + + if (it != Zero) push(it) + + def hasNext = index != 0 + @tailrec + def next(): V = + pop match { + case Bin(_,_, Tip(_, v), right) => + push(right) + v + case Bin(_, _, left, right) => + push(right) + push(left) + next() + case Tip(_, v) => v + // This should never happen. We don't allow Ordering.Zero in subtrees of the Ordering + // and don't return an Ordering.Iterator for Ordering.Zero. + case Zero => throw new IllegalStateException("empty subtree not allowed") + } + } + + object Iterator { + val Empty = new Iterator[Nothing](Ordering.empty[Nothing]) + def empty[V]: Iterator[V] = Empty.asInstanceOf[Iterator[V]] + } + + case object Zero extends Ordering[Nothing] { + // Important! Without this equals method in place, an infinite + // loop from Map.equals => size => pattern-match-on-Nil => equals + // develops. Case objects and custom equality don't mix without + // careful handling. + override def equals(that : Any): Boolean = that match { + case _: this.type => true + case _: Ordering[_] => false // The only empty Orderings are eq Nil + case _ => super.equals(that) + } + protected def format(sb: StringBuilder, prefix: String, subPrefix: String): Unit = sb ++= s"${prefix}Ø" + } + + final case class Tip[+T](ord: Int, value: T) extends Ordering[T] { + def withValue[S](s: S) = + if (s.asInstanceOf[AnyRef] eq value.asInstanceOf[AnyRef]) this.asInstanceOf[Tip[S]] + else Tip(ord, s) + protected def format(sb: StringBuilder, prefix: String, subPrefix: String): Unit = sb ++= s"${prefix}Tip(${toBinaryString(ord)} -> $value)\n" + } + + final case class Bin[+T](prefix: Int, mask: Int, left: Ordering[T], var right: Ordering[T @uncheckedCaptures] @scala.annotation.unchecked.uncheckedVariance) extends Ordering[T] { + def bin[S](left: Ordering[S], right: Ordering[S]): Ordering[S] = { + if ((this.left eq left) && (this.right eq right)) this.asInstanceOf[Bin[S]] + else Bin[S](prefix, mask, left, right) + } + protected def format(sb: StringBuilder, prefix: String, subPrefix: String): Unit = { + sb ++= s"${prefix}Bin(${toBinaryString(this.prefix)}:${toBinaryString(mask)})\n" + left.format(sb, subPrefix + "├── ", subPrefix + "│ ") + right.format(sb, subPrefix + "└── ", subPrefix + " ") + } + } + + private def branchMask(i: Int, j: Int) = highestOneBit(i ^ j) + + private def join[T](p1: Int, t1: Ordering[T], p2: Int, t2: Ordering[T]): Ordering[T] = { + val m = branchMask(p1, p2) + val p = mask(p1, m) + if (zero(p1, m)) Bin(p, m, t1, t2) + else Bin(p, m, t2, t1) + } + + private def bin[T](prefix: Int, mask: Int, left: Ordering[T], right: Ordering[T]): Ordering[T] = (left, right) match { + case (l, Zero) => l + case (Zero, r) => r + case (l, r) => Bin(prefix, mask, l, r) + } + } + + sealed abstract class Ordering[+T] { + import Ordering._ + import scala.annotation.tailrec + import scala.collection.generic.BitOperations.Int._ + + override final def toString: String = format + final def format: String = { + val sb = new StringBuilder + format(sb, "", "") + sb.toString() + } + protected def format(sb: StringBuilder, prefix: String, subPrefix: String): Unit + + @tailrec + final def head: T = this match { + case Zero => throw new NoSuchElementException("head of empty map") + case Tip(k, v) => v + case Bin(_, _, l, _) => l.head + } + + @tailrec + final def headOption: Option[T] = this match { + case Zero => None + case Tip(_, v) => Some(v) + case Bin(_, _, l, _) => l.headOption + } + + @tailrec + final def last: T = this match { + case Zero => throw new NoSuchElementException("last of empty map") + case Tip(_, v) => v + case Bin(_, _, _, r) => r.last + } + + @tailrec + final def lastOption: Option[T] = this match { + case Zero => None + case Tip(_, v) => Some(v) + case Bin(_, _, _, r) => r.lastOption + } + + @tailrec + final def ordinal: Int = this match { + case Zero => 0 + case Tip(o, _) => o + case Bin(_, _, _, r) => r.ordinal + } + + final def tail: Ordering[T] = this match { + case Zero => throw new NoSuchElementException("tail of empty map") + case Tip(_, _) => Zero + case Bin(p, m, l, r) => bin(p, m, l.tail, r) + } + + final def headTail: (T, Ordering[T]) = this match { + case Zero => throw new NoSuchElementException("init of empty map") + case Tip(_, v) => (v, Zero) + case Bin(p, m, l, r) => + val (head, tail) = l.headTail + (head, bin(p, m, tail, r)) + } + + final def init: Ordering[T] = this match { + case Zero => throw new NoSuchElementException("init of empty map") + case Tip(_, _) => Zero + case Bin(p, m, l, r) => + bin(p, m, l, r.init) + } + + final def initLast: (Ordering[T], T) = this match { + case Zero => throw new NoSuchElementException("init of empty map") + case Tip(_, v) => (Zero, v) + case Bin(p, m, l, r) => + val (init, last) = r.initLast + (bin(p, m, l, init), last) + } + + final def iterator: Iterator[T] = this match { + case Zero => Iterator.empty + case _ => new Iterator(this) + } + + final def include[S >: T](ordinal: Int, value: S): Ordering[S] = this match { + case Zero => + Tip(ordinal, value) + case Tip(o, _) => + if (ordinal == o) Tip(ordinal, value) + else join(ordinal, Tip(ordinal, value), o, this) + case Bin(p, m, l, r) => + if (!hasMatch(ordinal, p, m)) join(ordinal, Tip(ordinal, value), p, this) + else if (zero(ordinal, m)) Bin(p, m, l.include(ordinal, value), r) + else Bin(p, m, l, r.include(ordinal, value)) + } + + final def append[S >: T](ordinal: Int, value: S): Ordering[S] = this match { + case Zero => + Tip(ordinal, value) + case Tip(o, _) => + if (ordinal == o) Tip(ordinal, value) + else join(ordinal, Tip(ordinal, value), o, this) + case Bin(p, m, l, r) => + if (!hasMatch(ordinal, p, m)) join(ordinal, Tip(ordinal, value), p, this) + else if (zero(ordinal, m)) throw new IllegalArgumentException(s"Append called with ordinal out of range: $ordinal is not greater than current max ordinal ${this.ordinal}") + else Bin(p, m, l, r.append(ordinal, value)) + } + + @inline private[collection] final def appendInPlace[S >: T](ordinal: Int, value: S): Ordering[S] = appendInPlace1(null, ordinal, value) + private[collection] final def appendInPlace1[S >: T](parent: Bin[S], ordinal: Int, value: S): Ordering[S] = this match { + case Zero => + Tip(ordinal, value) + case Tip(o, _) if o >= ordinal => + throw new IllegalArgumentException(s"Append called with ordinal out of range: $o is not greater than current max ordinal ${this.ordinal}") + case Tip(o, _) if parent == null => + join(ordinal, Tip(ordinal, value), o, this) + case Tip(o, _) => + parent.right = join(ordinal, Tip(ordinal, value), o, this) + parent + case b @ Bin(p, m, _, r) => + if (!hasMatch(ordinal, p, m)) { + val b2 = join(ordinal, Tip(ordinal, value), p, this) + if (parent != null) { + parent.right = b2 + parent + } else b2 + } else if (zero(ordinal, m)) throw new IllegalArgumentException(s"Append called with ordinal out of range: $ordinal is not greater than current max ordinal ${this.ordinal}") + else { + r.appendInPlace1(b, ordinal, value) + this + } + } + + final def exclude(ordinal: Int): Ordering[T] = this match { + case Zero => + Zero + case Tip(o, _) => + if (ordinal == o) Zero + else this + case Bin(p, m, l, r) => + if (!hasMatch(ordinal, p, m)) this + else if (zero(ordinal, m)) bin(p, m, l.exclude(ordinal), r) + else bin(p, m, l, r.exclude(ordinal)) + } + + final def splitAt(n: Int): (Ordering[T], Ordering[T]) = { + var rear = Ordering.empty[T] + var i = n + (modifyOrRemove { (o, v) => + i -= 1 + if (i >= 0) Some(v) + else { + rear = rear.appendInPlace(o, v) + None + } + }, rear) + } + + /** + * A combined transform and filter function. Returns an `Ordering` such that + * for each `(key, value)` mapping in this map, if `f(key, value) == None` + * the map contains no mapping for key, and if `f(key, value) == Some(x)` the + * map contains `(key, x)`. + * + * @tparam S The type of the values in the resulting `LongMap`. + * @param f The transforming function. + * @return The modified map. + */ + final def modifyOrRemove[S](f: (Int, T) => Option[S]): Ordering[S] = this match { + case Zero => Zero + case Tip(key, value) => + f(key, value) match { + case None => Zero + case Some(value2) => + // hack to preserve sharing + if (value.asInstanceOf[AnyRef] eq value2.asInstanceOf[AnyRef]) this.asInstanceOf[Ordering[S]] + else Tip(key, value2) + } + case Bin(prefix, mask, left, right) => + val l = left.modifyOrRemove(f) + val r = right.modifyOrRemove(f) + if ((left eq l) && (right eq r)) this.asInstanceOf[Ordering[S]] + else bin(prefix, mask, l, r) + } + } +} From 9ba2c39e8a689b5e5c6048efb5bd82dda91d4bee Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 19:16:23 +0100 Subject: [PATCH 77/89] Add unchecked LazyList to stdlib --- .../collection/immutable/LazyList.scala | 1381 +++++++++++++++++ 1 file changed, 1381 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/immutable/LazyList.scala diff --git a/tests/pos-special/stdlib/collection/immutable/LazyList.scala b/tests/pos-special/stdlib/collection/immutable/LazyList.scala new file mode 100644 index 000000000000..8b7ad26dc5ae --- /dev/null +++ b/tests/pos-special/stdlib/collection/immutable/LazyList.scala @@ -0,0 +1,1381 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package immutable + +import java.io.{ObjectInputStream, ObjectOutputStream} +import java.lang.{StringBuilder => JStringBuilder} + +import scala.annotation.tailrec +import scala.collection.generic.SerializeEnd +import scala.collection.mutable.{Builder, ReusableBuilder, StringBuilder} +import scala.language.implicitConversions +import scala.runtime.Statics + +/** This class implements an immutable linked list. We call it "lazy" + * because it computes its elements only when they are needed. + * + * Elements are memoized; that is, the value of each element is computed at most once. + * + * Elements are computed in-order and are never skipped. In other words, + * accessing the tail causes the head to be computed first. + * + * How lazy is a `LazyList`? When you have a value of type `LazyList`, you + * don't know yet whether the list is empty or not. If you learn that it is non-empty, + * then you also know that the head has been computed. But the tail is itself + * a `LazyList`, whose emptiness-or-not might remain undetermined. + * + * A `LazyList` may be infinite. For example, `LazyList.from(0)` contains + * all of the natural numbers 0, 1, 2, and so on. For infinite sequences, + * some methods (such as `count`, `sum`, `max` or `min`) will not terminate. + * + * Here is an example: + * + * {{{ + * import scala.math.BigInt + * object Main extends App { + * val fibs: LazyList[BigInt] = + * BigInt(0) #:: BigInt(1) #:: fibs.zip(fibs.tail).map{ n => n._1 + n._2 } + * fibs.take(5).foreach(println) + * } + * + * // prints + * // + * // 0 + * // 1 + * // 1 + * // 2 + * // 3 + * }}} + * + * To illustrate, let's add some output to the definition `fibs`, so we + * see what's going on. + * + * {{{ + * import scala.math.BigInt + * object Main extends App { + * val fibs: LazyList[BigInt] = + * BigInt(0) #:: BigInt(1) #:: + * fibs.zip(fibs.tail).map{ n => + * println(s"Adding \${n._1} and \${n._2}") + * n._1 + n._2 + * } + * fibs.take(5).foreach(println) + * fibs.take(6).foreach(println) + * } + * + * // prints + * // + * // 0 + * // 1 + * // Adding 0 and 1 + * // 1 + * // Adding 1 and 1 + * // 2 + * // Adding 1 and 2 + * // 3 + * + * // And then prints + * // + * // 0 + * // 1 + * // 1 + * // 2 + * // 3 + * // Adding 2 and 3 + * // 5 + * }}} + * + * Note that the definition of `fibs` uses `val` not `def`. The memoization of the + * `LazyList` requires us to have somewhere to store the information and a `val` + * allows us to do that. + * + * Further remarks about the semantics of `LazyList`: + * + * - Though the `LazyList` changes as it is accessed, this does not + * contradict its immutability. Once the values are memoized they do + * not change. Values that have yet to be memoized still "exist", they + * simply haven't been computed yet. + * + * - One must be cautious of memoization; it can eat up memory if you're not + * careful. That's because memoization of the `LazyList` creates a structure much like + * [[scala.collection.immutable.List]]. As long as something is holding on to + * the head, the head holds on to the tail, and so on recursively. + * If, on the other hand, there is nothing holding on to the head (e.g. if we used + * `def` to define the `LazyList`) then once it is no longer being used directly, + * it disappears. + * + * - Note that some operations, including [[drop]], [[dropWhile]], + * [[flatMap]] or [[collect]] may process a large number of intermediate + * elements before returning. + * + * Here's another example. Let's start with the natural numbers and iterate + * over them. + * + * {{{ + * // We'll start with a silly iteration + * def loop(s: String, i: Int, iter: Iterator[Int]): Unit = { + * // Stop after 200,000 + * if (i < 200001) { + * if (i % 50000 == 0) println(s + i) + * loop(s, iter.next(), iter) + * } + * } + * + * // Our first LazyList definition will be a val definition + * val lazylist1: LazyList[Int] = { + * def loop(v: Int): LazyList[Int] = v #:: loop(v + 1) + * loop(0) + * } + * + * // Because lazylist1 is a val, everything that the iterator produces is held + * // by virtue of the fact that the head of the LazyList is held in lazylist1 + * val it1 = lazylist1.iterator + * loop("Iterator1: ", it1.next(), it1) + * + * // We can redefine this LazyList such that all we have is the Iterator left + * // and allow the LazyList to be garbage collected as required. Using a def + * // to provide the LazyList ensures that no val is holding onto the head as + * // is the case with lazylist1 + * def lazylist2: LazyList[Int] = { + * def loop(v: Int): LazyList[Int] = v #:: loop(v + 1) + * loop(0) + * } + * val it2 = lazylist2.iterator + * loop("Iterator2: ", it2.next(), it2) + * + * // And, of course, we don't actually need a LazyList at all for such a simple + * // problem. There's no reason to use a LazyList if you don't actually need + * // one. + * val it3 = new Iterator[Int] { + * var i = -1 + * def hasNext = true + * def next(): Int = { i += 1; i } + * } + * loop("Iterator3: ", it3.next(), it3) + * }}} + * + * - In the `fibs` example earlier, the fact that `tail` works at all is of interest. + * `fibs` has an initial `(0, 1, LazyList(...))`, so `tail` is deterministic. + * If we defined `fibs` such that only `0` were concretely known, then the act + * of determining `tail` would require the evaluation of `tail`, so the + * computation would be unable to progress, as in this code: + * {{{ + * // The first time we try to access the tail we're going to need more + * // information which will require us to recurse, which will require us to + * // recurse, which... + * lazy val sov: LazyList[Vector[Int]] = Vector(0) #:: sov.zip(sov.tail).map { n => n._1 ++ n._2 } + * }}} + * + * The definition of `fibs` above creates a larger number of objects than + * necessary depending on how you might want to implement it. The following + * implementation provides a more "cost effective" implementation due to the + * fact that it has a more direct route to the numbers themselves: + * + * {{{ + * lazy val fib: LazyList[Int] = { + * def loop(h: Int, n: Int): LazyList[Int] = h #:: loop(n, h + n) + * loop(1, 1) + * } + * }}} + * + * The head, the tail and whether the list is empty or not can be initially unknown. + * Once any of those are evaluated, they are all known, though if the tail is + * built with `#::` or `#:::`, it's content still isn't evaluated. Instead, evaluating + * the tails content is deferred until the tails empty status, head or tail is + * evaluated. + * + * Delaying the evaluation of whether a LazyList is empty or not until it's needed + * allows LazyList to not eagerly evaluate any elements on a call to `filter`. + * + * Only when it's further evaluated (which may be never!) any of the elements gets + * forced. + * + * for example: + * + * {{{ + * def tailWithSideEffect: LazyList[Nothing] = { + * println("getting empty LazyList") + * LazyList.empty + * } + * + * val emptyTail = tailWithSideEffect // prints "getting empty LazyList" + * + * val suspended = 1 #:: tailWithSideEffect // doesn't print anything + * val tail = suspended.tail // although the tail is evaluated, *still* nothing is yet printed + * val filtered = tail.filter(_ => false) // still nothing is printed + * filtered.isEmpty // prints "getting empty LazyList" + * }}} + * + * @tparam A the type of the elements contained in this lazy list. + * + * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#lazylists "Scala's Collection Library overview"]] + * section on `LazyLists` for more information. + * @define Coll `LazyList` + * @define coll lazy list + * @define orderDependent + * @define orderDependentFold + * @define appendStackSafety Note: Repeated chaining of calls to append methods (`appended`, + * `appendedAll`, `lazyAppendedAll`) without forcing any of the + * intermediate resulting lazy lists may overflow the stack when + * the final result is forced. + * @define preservesLaziness This method preserves laziness; elements are only evaluated + * individually as needed. + * @define initiallyLazy This method does not evaluate anything until an operation is performed + * on the result (e.g. calling `head` or `tail`, or checking if it is empty). + * @define evaluatesAllElements This method evaluates all elements of the collection. + */ +@SerialVersionUID(3L) +final class LazyList[+A] private(private[this] var lazyState: () => LazyList.State[A]) + extends AbstractSeq[A] + with LinearSeq[A] + with LinearSeqOps[A, LazyList, LazyList[A]] + with IterableFactoryDefaults[A, LazyList] + with Serializable { + import LazyList._ + + @volatile private[this] var stateEvaluated: Boolean = false + @inline private def stateDefined: Boolean = stateEvaluated + private[this] var midEvaluation = false + + private lazy val state: State[A] = { + // if it's already mid-evaluation, we're stuck in an infinite + // self-referential loop (also it's empty) + if (midEvaluation) { + throw new RuntimeException("self-referential LazyList or a derivation thereof has no more elements") + } + midEvaluation = true + val res = try lazyState() finally midEvaluation = false + // if we set it to `true` before evaluating, we may infinite loop + // if something expects `state` to already be evaluated + stateEvaluated = true + lazyState = null // allow GC + res + } + + override def iterableFactory: SeqFactory[LazyList] = LazyList + + override def isEmpty: Boolean = state eq State.Empty + + /** @inheritdoc + * + * $preservesLaziness + */ + override def knownSize: Int = if (knownIsEmpty) 0 else -1 + + override def head: A = state.head + + override def tail: LazyList[A] = state.tail + + @inline private[this] def knownIsEmpty: Boolean = stateEvaluated && (isEmpty: @inline) + @inline private def knownNonEmpty: Boolean = stateEvaluated && !(isEmpty: @inline) + + /** Evaluates all undefined elements of the lazy list. + * + * This method detects cycles in lazy lists, and terminates after all + * elements of the cycle are evaluated. For example: + * + * {{{ + * val ring: LazyList[Int] = 1 #:: 2 #:: 3 #:: ring + * ring.force + * ring.toString + * + * // prints + * // + * // LazyList(1, 2, 3, ...) + * }}} + * + * This method will *not* terminate for non-cyclic infinite-sized collections. + * + * @return this + */ + def force: this.type = { + // Use standard 2x 1x iterator trick for cycle detection ("those" is slow one) + var these, those: LazyList[A] = this + if (!these.isEmpty) { + these = these.tail + } + while (those ne these) { + if (these.isEmpty) return this + these = these.tail + if (these.isEmpty) return this + these = these.tail + if (these eq those) return this + those = those.tail + } + this + } + + /** @inheritdoc + * + * The iterator returned by this method preserves laziness; elements are + * only evaluated individually as needed. + */ + override def iterator: Iterator[A] = + if (knownIsEmpty) Iterator.empty + else new LazyIterator(this) + + /** Apply the given function `f` to each element of this linear sequence + * (while respecting the order of the elements). + * + * @param f The treatment to apply to each element. + * @note Overridden here as final to trigger tail-call optimization, which + * replaces 'this' with 'tail' at each iteration. This is absolutely + * necessary for allowing the GC to collect the underlying LazyList as elements + * are consumed. + * @note This function will force the realization of the entire LazyList + * unless the `f` throws an exception. + */ + @tailrec + override def foreach[U](f: A => U): Unit = { + if (!isEmpty) { + f(head) + tail.foreach(f) + } + } + + /** LazyList specialization of foldLeft which allows GC to collect along the + * way. + * + * @tparam B The type of value being accumulated. + * @param z The initial value seeded into the function `op`. + * @param op The operation to perform on successive elements of the `LazyList`. + * @return The accumulated value from successive applications of `op`. + */ + @tailrec + override def foldLeft[B](z: B)(op: (B, A) => B): B = + if (isEmpty) z + else tail.foldLeft(op(z, head))(op) + + // State.Empty doesn't use the SerializationProxy + protected[this] def writeReplace(): AnyRef = + if (knownNonEmpty) new LazyList.SerializationProxy[A](this) else this + + override protected[this] def className = "LazyList" + + /** The lazy list resulting from the concatenation of this lazy list with the argument lazy list. + * + * $preservesLaziness + * + * $appendStackSafety + * + * @param suffix The collection that gets appended to this lazy list + * @return The lazy list containing elements of this lazy list and the iterable object. + */ + def lazyAppendedAll[B >: A](suffix: => collection.IterableOnce[B]): LazyList[B] = + newLL { + if (isEmpty) suffix match { + case lazyList: LazyList[B] => lazyList.state // don't recompute the LazyList + case coll if coll.knownSize == 0 => State.Empty + case coll => stateFromIterator(coll.iterator) + } + else sCons(head, tail lazyAppendedAll suffix) + } + + /** @inheritdoc + * + * $preservesLaziness + * + * $appendStackSafety + */ + override def appendedAll[B >: A](suffix: IterableOnce[B]): LazyList[B] = + if (knownIsEmpty) LazyList.from(suffix) + else lazyAppendedAll(suffix) + + /** @inheritdoc + * + * $preservesLaziness + * + * $appendStackSafety + */ + override def appended[B >: A](elem: B): LazyList[B] = + if (knownIsEmpty) newLL(sCons(elem, LazyList.empty)) + else lazyAppendedAll(Iterator.single(elem)) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def scanLeft[B](z: B)(op: (B, A) => B): LazyList[B] = + if (knownIsEmpty) newLL(sCons(z, LazyList.empty)) + else newLL(scanLeftState(z)(op)) + + private def scanLeftState[B](z: B)(op: (B, A) => B): State[B] = + sCons( + z, + newLL { + if (isEmpty) State.Empty + else tail.scanLeftState(op(z, head))(op) + } + ) + + /** LazyList specialization of reduceLeft which allows GC to collect + * along the way. + * + * @tparam B The type of value being accumulated. + * @param f The operation to perform on successive elements of the `LazyList`. + * @return The accumulated value from successive applications of `f`. + */ + override def reduceLeft[B >: A](f: (B, A) => B): B = { + if (this.isEmpty) throw new UnsupportedOperationException("empty.reduceLeft") + else { + var reducedRes: B = this.head + var left: LazyList[A] = this.tail + while (!left.isEmpty) { + reducedRes = f(reducedRes, left.head) + left = left.tail + } + reducedRes + } + } + + /** @inheritdoc + * + * $preservesLaziness + */ + override def partition(p: A => Boolean): (LazyList[A], LazyList[A]) = (filter(p), filterNot(p)) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def partitionMap[A1, A2](f: A => Either[A1, A2]): (LazyList[A1], LazyList[A2]) = { + val (left, right) = map(f).partition(_.isLeft) + (left.map(_.asInstanceOf[Left[A1, _]].value), right.map(_.asInstanceOf[Right[_, A2]].value)) + } + + /** @inheritdoc + * + * $preservesLaziness + */ + override def filter(pred: A => Boolean): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else LazyList.filterImpl(this, pred, isFlipped = false) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def filterNot(pred: A => Boolean): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else LazyList.filterImpl(this, pred, isFlipped = true) + + /** A `collection.WithFilter` which allows GC of the head of lazy list during processing. + * + * This method is not particularly useful for a lazy list, as [[filter]] already preserves + * laziness. + * + * The `collection.WithFilter` returned by this method preserves laziness; elements are + * only evaluated individually as needed. + */ + override def withFilter(p: A => Boolean): collection.WithFilter[A, LazyList] = + new LazyList.WithFilter(coll, p) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def prepended[B >: A](elem: B): LazyList[B] = newLL(sCons(elem, this)) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def prependedAll[B >: A](prefix: collection.IterableOnce[B]): LazyList[B] = + if (knownIsEmpty) LazyList.from(prefix) + else if (prefix.knownSize == 0) this + else newLL(stateFromIteratorConcatSuffix(prefix.iterator)(state)) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def map[B](f: A => B): LazyList[B] = + if (knownIsEmpty) LazyList.empty + else (mapImpl(f): @inline) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def tapEach[U](f: A => U): LazyList[A] = map { a => f(a); a } + + private def mapImpl[B](f: A => B): LazyList[B] = + newLL { + if (isEmpty) State.Empty + else sCons(f(head), tail.mapImpl(f)) + } + + /** @inheritdoc + * + * $preservesLaziness + */ + override def collect[B](pf: PartialFunction[A, B]): LazyList[B] = + if (knownIsEmpty) LazyList.empty + else LazyList.collectImpl(this, pf) + + /** @inheritdoc + * + * This method does not evaluate any elements further than + * the first element for which the partial function is defined. + */ + @tailrec + override def collectFirst[B](pf: PartialFunction[A, B]): Option[B] = + if (isEmpty) None + else { + val res = pf.applyOrElse(head, LazyList.anyToMarker.asInstanceOf[A => B]) + if (res.asInstanceOf[AnyRef] eq Statics.pfMarker) tail.collectFirst(pf) + else Some(res) + } + + /** @inheritdoc + * + * This method does not evaluate any elements further than + * the first element matching the predicate. + */ + @tailrec + override def find(p: A => Boolean): Option[A] = + if (isEmpty) None + else { + val elem = head + if (p(elem)) Some(elem) + else tail.find(p) + } + + /** @inheritdoc + * + * $preservesLaziness + */ + // optimisations are not for speed, but for functionality + // see tickets #153, #498, #2147, and corresponding tests in run/ (as well as run/stream_flatmap_odds.scala) + override def flatMap[B](f: A => IterableOnce[B]): LazyList[B] = + if (knownIsEmpty) LazyList.empty + else LazyList.flatMapImpl(this, f) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def flatten[B](implicit asIterable: A => IterableOnce[B]): LazyList[B] = flatMap(asIterable) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def zip[B](that: collection.IterableOnce[B]): LazyList[(A, B)] = + if (this.knownIsEmpty || that.knownSize == 0) LazyList.empty + else newLL(zipState(that.iterator)) + + private def zipState[B](it: Iterator[B]): State[(A, B)] = + if (this.isEmpty || !it.hasNext) State.Empty + else sCons((head, it.next()), newLL { tail zipState it }) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def zipWithIndex: LazyList[(A, Int)] = this zip LazyList.from(0) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def zipAll[A1 >: A, B](that: collection.Iterable[B], thisElem: A1, thatElem: B): LazyList[(A1, B)] = { + if (this.knownIsEmpty) { + if (that.knownSize == 0) LazyList.empty + else LazyList.continually(thisElem) zip that + } else { + if (that.knownSize == 0) zip(LazyList.continually(thatElem)) + else newLL(zipAllState(that.iterator, thisElem, thatElem)) + } + } + + private def zipAllState[A1 >: A, B](it: Iterator[B], thisElem: A1, thatElem: B): State[(A1, B)] = { + if (it.hasNext) { + if (this.isEmpty) sCons((thisElem, it.next()), newLL { LazyList.continually(thisElem) zipState it }) + else sCons((this.head, it.next()), newLL { this.tail.zipAllState(it, thisElem, thatElem) }) + } else { + if (this.isEmpty) State.Empty + else sCons((this.head, thatElem), this.tail zip LazyList.continually(thatElem)) + } + } + + /** @inheritdoc + * + * This method is not particularly useful for a lazy list, as [[zip]] already preserves + * laziness. + * + * The `collection.LazyZip2` returned by this method preserves laziness; elements are + * only evaluated individually as needed. + */ + // just in case it can be meaningfully overridden at some point + override def lazyZip[B](that: collection.Iterable[B]): LazyZip2[A, B, LazyList.this.type] = + super.lazyZip(that) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def unzip[A1, A2](implicit asPair: A => (A1, A2)): (LazyList[A1], LazyList[A2]) = + (map(asPair(_)._1), map(asPair(_)._2)) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def unzip3[A1, A2, A3](implicit asTriple: A => (A1, A2, A3)): (LazyList[A1], LazyList[A2], LazyList[A3]) = + (map(asTriple(_)._1), map(asTriple(_)._2), map(asTriple(_)._3)) + + /** @inheritdoc + * + * $initiallyLazy + * Additionally, it preserves laziness for all except the first `n` elements. + */ + override def drop(n: Int): LazyList[A] = + if (n <= 0) this + else if (knownIsEmpty) LazyList.empty + else LazyList.dropImpl(this, n) + + /** @inheritdoc + * + * $initiallyLazy + * Additionally, it preserves laziness for all elements after the predicate returns `false`. + */ + override def dropWhile(p: A => Boolean): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else LazyList.dropWhileImpl(this, p) + + /** @inheritdoc + * + * $initiallyLazy + */ + override def dropRight(n: Int): LazyList[A] = { + if (n <= 0) this + else if (knownIsEmpty) LazyList.empty + else newLL { + var scout = this + var remaining = n + // advance scout n elements ahead (or until empty) + while (remaining > 0 && !scout.isEmpty) { + remaining -= 1 + scout = scout.tail + } + dropRightState(scout) + } + } + + private def dropRightState(scout: LazyList[_]): State[A] = + if (scout.isEmpty) State.Empty + else sCons(head, newLL(tail.dropRightState(scout.tail))) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def take(n: Int): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else (takeImpl(n): @inline) + + private def takeImpl(n: Int): LazyList[A] = { + if (n <= 0) LazyList.empty + else newLL { + if (isEmpty) State.Empty + else sCons(head, tail.takeImpl(n - 1)) + } + } + + /** @inheritdoc + * + * $preservesLaziness + */ + override def takeWhile(p: A => Boolean): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else (takeWhileImpl(p): @inline) + + private def takeWhileImpl(p: A => Boolean): LazyList[A] = + newLL { + if (isEmpty || !p(head)) State.Empty + else sCons(head, tail.takeWhileImpl(p)) + } + + /** @inheritdoc + * + * $initiallyLazy + */ + override def takeRight(n: Int): LazyList[A] = + if (n <= 0 || knownIsEmpty) LazyList.empty + else LazyList.takeRightImpl(this, n) + + /** @inheritdoc + * + * $initiallyLazy + * Additionally, it preserves laziness for all but the first `from` elements. + */ + override def slice(from: Int, until: Int): LazyList[A] = take(until).drop(from) + + /** @inheritdoc + * + * $evaluatesAllElements + */ + override def reverse: LazyList[A] = reverseOnto(LazyList.empty) + + // need contravariant type B to make the compiler happy - still returns LazyList[A] + @tailrec + private def reverseOnto[B >: A](tl: LazyList[B]): LazyList[B] = + if (isEmpty) tl + else tail.reverseOnto(newLL(sCons(head, tl))) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def diff[B >: A](that: collection.Seq[B]): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else super.diff(that) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def intersect[B >: A](that: collection.Seq[B]): LazyList[A] = + if (knownIsEmpty) LazyList.empty + else super.intersect(that) + + @tailrec + private def lengthGt(len: Int): Boolean = + if (len < 0) true + else if (isEmpty) false + else tail.lengthGt(len - 1) + + /** @inheritdoc + * + * The iterator returned by this method mostly preserves laziness; + * a single element ahead of the iterator is evaluated. + */ + override def grouped(size: Int): Iterator[LazyList[A]] = { + require(size > 0, "size must be positive, but was " + size) + slidingImpl(size = size, step = size) + } + + /** @inheritdoc + * + * The iterator returned by this method mostly preserves laziness; + * `size - step max 1` elements ahead of the iterator are evaluated. + */ + override def sliding(size: Int, step: Int): Iterator[LazyList[A]] = { + require(size > 0 && step > 0, s"size=$size and step=$step, but both must be positive") + slidingImpl(size = size, step = step) + } + + @inline private def slidingImpl(size: Int, step: Int): Iterator[LazyList[A]] = + if (knownIsEmpty) Iterator.empty + else new SlidingIterator[A](this, size = size, step = step) + + /** @inheritdoc + * + * $preservesLaziness + */ + override def padTo[B >: A](len: Int, elem: B): LazyList[B] = { + if (len <= 0) this + else newLL { + if (isEmpty) LazyList.fill(len)(elem).state + else sCons(head, tail.padTo(len - 1, elem)) + } + } + + /** @inheritdoc + * + * $preservesLaziness + */ + override def patch[B >: A](from: Int, other: IterableOnce[B], replaced: Int): LazyList[B] = + if (knownIsEmpty) LazyList from other + else patchImpl(from, other, replaced) + + private def patchImpl[B >: A](from: Int, other: IterableOnce[B], replaced: Int): LazyList[B] = + newLL { + if (from <= 0) stateFromIteratorConcatSuffix(other.iterator)(LazyList.dropImpl(this, replaced).state) + else if (isEmpty) stateFromIterator(other.iterator) + else sCons(head, tail.patchImpl(from - 1, other, replaced)) + } + + /** @inheritdoc + * + * $evaluatesAllElements + */ + // overridden just in case a lazy implementation is developed at some point + override def transpose[B](implicit asIterable: A => collection.Iterable[B]): LazyList[LazyList[B]] = super.transpose + + /** @inheritdoc + * + * $preservesLaziness + */ + override def updated[B >: A](index: Int, elem: B): LazyList[B] = + if (index < 0) throw new IndexOutOfBoundsException(s"$index") + else updatedImpl(index, elem, index) + + private def updatedImpl[B >: A](index: Int, elem: B, startIndex: Int): LazyList[B] = { + newLL { + if (index <= 0) sCons(elem, tail) + else if (tail.isEmpty) throw new IndexOutOfBoundsException(startIndex.toString) + else sCons(head, tail.updatedImpl(index - 1, elem, startIndex)) + } + } + + /** Appends all elements of this $coll to a string builder using start, end, and separator strings. + * The written text begins with the string `start` and ends with the string `end`. + * Inside, the string representations (w.r.t. the method `toString`) + * of all elements of this $coll are separated by the string `sep`. + * + * An undefined state is represented with `"<not computed>"` and cycles are represented with `"<cycle>"`. + * + * $evaluatesAllElements + * + * @param sb the string builder to which elements are appended. + * @param start the starting string. + * @param sep the separator string. + * @param end the ending string. + * @return the string builder `b` to which elements were appended. + */ + override def addString(sb: StringBuilder, start: String, sep: String, end: String): sb.type = { + force + addStringNoForce(sb.underlying, start, sep, end) + sb + } + + private[this] def addStringNoForce(b: JStringBuilder, start: String, sep: String, end: String): JStringBuilder = { + b.append(start) + if (!stateDefined) b.append("") + else if (!isEmpty) { + b.append(head) + var cursor = this + @inline def appendCursorElement(): Unit = b.append(sep).append(cursor.head) + var scout = tail + @inline def scoutNonEmpty: Boolean = scout.stateDefined && !scout.isEmpty + if ((cursor ne scout) && (!scout.stateDefined || (cursor.state ne scout.state))) { + cursor = scout + if (scoutNonEmpty) { + scout = scout.tail + // Use 2x 1x iterator trick for cycle detection; slow iterator can add strings + while ((cursor ne scout) && scoutNonEmpty && (cursor.state ne scout.state)) { + appendCursorElement() + cursor = cursor.tail + scout = scout.tail + if (scoutNonEmpty) scout = scout.tail + } + } + } + if (!scoutNonEmpty) { // Not a cycle, scout hit an end + while (cursor ne scout) { + appendCursorElement() + cursor = cursor.tail + } + // if cursor (eq scout) has state defined, it is empty; else unknown state + if (!cursor.stateDefined) b.append(sep).append("") + } else { + @inline def same(a: LazyList[A], b: LazyList[A]): Boolean = (a eq b) || (a.state eq b.state) + // Cycle. + // If we have a prefix of length P followed by a cycle of length C, + // the scout will be at position (P%C) in the cycle when the cursor + // enters it at P. They'll then collide when the scout advances another + // C - (P%C) ahead of the cursor. + // If we run the scout P farther, then it will be at the start of + // the cycle: (C - (P%C) + (P%C)) == C == 0. So if another runner + // starts at the beginning of the prefix, they'll collide exactly at + // the start of the loop. + var runner = this + var k = 0 + while (!same(runner, scout)) { + runner = runner.tail + scout = scout.tail + k += 1 + } + // Now runner and scout are at the beginning of the cycle. Advance + // cursor, adding to string, until it hits; then we'll have covered + // everything once. If cursor is already at beginning, we'd better + // advance one first unless runner didn't go anywhere (in which case + // we've already looped once). + if (same(cursor, scout) && (k > 0)) { + appendCursorElement() + cursor = cursor.tail + } + while (!same(cursor, scout)) { + appendCursorElement() + cursor = cursor.tail + } + b.append(sep).append("") + } + } + b.append(end) + } + + /** $preservesLaziness + * + * @return a string representation of this collection. An undefined state is + * represented with `"<not computed>"` and cycles are represented with `"<cycle>"` + * + * Examples: + * + * - `"LazyList(4, <not computed>)"`, a non-empty lazy list ; + * - `"LazyList(1, 2, 3, <not computed>)"`, a lazy list with at least three elements ; + * - `"LazyList(1, 2, 3, <cycle>)"`, an infinite lazy list that contains + * a cycle at the fourth element. + */ + override def toString(): String = addStringNoForce(new JStringBuilder(className), "(", ", ", ")").toString + + /** @inheritdoc + * + * $preservesLaziness + */ + @deprecated("Check .knownSize instead of .hasDefiniteSize for more actionable information (see scaladoc for details)", "2.13.0") + override def hasDefiniteSize: Boolean = { + if (!stateDefined) false + else if (isEmpty) true + else { + // Two-iterator trick (2x & 1x speed) for cycle detection. + var those = this + var these = tail + while (those ne these) { + if (!these.stateDefined) return false + else if (these.isEmpty) return true + these = these.tail + if (!these.stateDefined) return false + else if (these.isEmpty) return true + these = these.tail + if (those eq these) return false + those = those.tail + } + false // Cycle detected + } + } +} + +/** + * $factoryInfo + * @define coll lazy list + * @define Coll `LazyList` + */ +@SerialVersionUID(3L) +object LazyList extends SeqFactory[LazyList] { + // Eagerly evaluate cached empty instance + private[this] val _empty = newLL(State.Empty).force + + private sealed trait State[+A] extends Serializable { + def head: A + def tail: LazyList[A] + } + + private object State { + @SerialVersionUID(3L) + object Empty extends State[Nothing] { + def head: Nothing = throw new NoSuchElementException("head of empty lazy list") + def tail: LazyList[Nothing] = throw new UnsupportedOperationException("tail of empty lazy list") + } + + @SerialVersionUID(3L) + final class Cons[A](val head: A, val tail: LazyList[A]) extends State[A] + } + + /** Creates a new LazyList. */ + @inline private def newLL[A](state: => State[A]): LazyList[A] = new LazyList[A](() => state) + + /** Creates a new State.Cons. */ + @inline private def sCons[A](hd: A, tl: LazyList[A]): State[A] = new State.Cons[A](hd, tl) + + private val anyToMarker: Any => Any = _ => Statics.pfMarker + + /* All of the following `Impl` methods are carefully written so as not to + * leak the beginning of the `LazyList`. They copy the initial `LazyList` (`ll`) into + * `var rest`, which gets closed over as a `scala.runtime.ObjectRef`, thus not permanently + * leaking the head of the `LazyList`. Additionally, the methods are written so that, should + * an exception be thrown by the evaluation of the `LazyList` or any supplied function, they + * can continue their execution where they left off. + */ + + private def filterImpl[A](ll: LazyList[A], p: A => Boolean, isFlipped: Boolean): LazyList[A] = { + // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD + var restRef = ll // val restRef = new ObjectRef(ll) + newLL { + var elem: A = null.asInstanceOf[A] + var found = false + var rest = restRef // var rest = restRef.elem + while (!found && !rest.isEmpty) { + elem = rest.head + found = p(elem) != isFlipped + rest = rest.tail + restRef = rest // restRef.elem = rest + } + if (found) sCons(elem, filterImpl(rest, p, isFlipped)) else State.Empty + } + } + + private def collectImpl[A, B](ll: LazyList[A], pf: PartialFunction[A, B]): LazyList[B] = { + // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD + var restRef = ll // val restRef = new ObjectRef(ll) + newLL { + val marker = Statics.pfMarker + val toMarker = anyToMarker.asInstanceOf[A => B] // safe because Function1 is erased + + var res: B = marker.asInstanceOf[B] // safe because B is unbounded + var rest = restRef // var rest = restRef.elem + while((res.asInstanceOf[AnyRef] eq marker) && !rest.isEmpty) { + res = pf.applyOrElse(rest.head, toMarker) + rest = rest.tail + restRef = rest // restRef.elem = rest + } + if (res.asInstanceOf[AnyRef] eq marker) State.Empty + else sCons(res, collectImpl(rest, pf)) + } + } + + private def flatMapImpl[A, B](ll: LazyList[A], f: A => IterableOnce[B]): LazyList[B] = { + // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD + var restRef = ll // val restRef = new ObjectRef(ll) + newLL { + var it: Iterator[B] = null + var itHasNext = false + var rest = restRef // var rest = restRef.elem + while (!itHasNext && !rest.isEmpty) { + it = f(rest.head).iterator + itHasNext = it.hasNext + if (!itHasNext) { // wait to advance `rest` because `it.next()` can throw + rest = rest.tail + restRef = rest // restRef.elem = rest + } + } + if (itHasNext) { + val head = it.next() + rest = rest.tail + restRef = rest // restRef.elem = rest + sCons(head, newLL(stateFromIteratorConcatSuffix(it)(flatMapImpl(rest, f).state))) + } else State.Empty + } + } + + private def dropImpl[A](ll: LazyList[A], n: Int): LazyList[A] = { + // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD + var restRef = ll // val restRef = new ObjectRef(ll) + var iRef = n // val iRef = new IntRef(n) + newLL { + var rest = restRef // var rest = restRef.elem + var i = iRef // var i = iRef.elem + while (i > 0 && !rest.isEmpty) { + rest = rest.tail + restRef = rest // restRef.elem = rest + i -= 1 + iRef = i // iRef.elem = i + } + rest.state + } + } + + private def dropWhileImpl[A](ll: LazyList[A], p: A => Boolean): LazyList[A] = { + // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD + var restRef = ll // val restRef = new ObjectRef(ll) + newLL { + var rest = restRef // var rest = restRef.elem + while (!rest.isEmpty && p(rest.head)) { + rest = rest.tail + restRef = rest // restRef.elem = rest + } + rest.state + } + } + + private def takeRightImpl[A](ll: LazyList[A], n: Int): LazyList[A] = { + // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD + var restRef = ll // val restRef = new ObjectRef(ll) + var scoutRef = ll // val scoutRef = new ObjectRef(ll) + var remainingRef = n // val remainingRef = new IntRef(n) + newLL { + var scout = scoutRef // var scout = scoutRef.elem + var remaining = remainingRef // var remaining = remainingRef.elem + // advance `scout` `n` elements ahead (or until empty) + while (remaining > 0 && !scout.isEmpty) { + scout = scout.tail + scoutRef = scout // scoutRef.elem = scout + remaining -= 1 + remainingRef = remaining // remainingRef.elem = remaining + } + var rest = restRef // var rest = restRef.elem + // advance `rest` and `scout` in tandem until `scout` reaches the end + while(!scout.isEmpty) { + scout = scout.tail + scoutRef = scout // scoutRef.elem = scout + rest = rest.tail // can't throw an exception as `scout` has already evaluated its tail + restRef = rest // restRef.elem = rest + } + // `rest` is the last `n` elements (or all of them) + rest.state + } + } + + /** An alternative way of building and matching lazy lists using LazyList.cons(hd, tl). + */ + object cons { + /** A lazy list consisting of a given first element and remaining elements + * @param hd The first element of the result lazy list + * @param tl The remaining elements of the result lazy list + */ + def apply[A](hd: => A, tl: => LazyList[A]): LazyList[A] = newLL(sCons(hd, newLL(tl.state))) + + /** Maps a lazy list to its head and tail */ + def unapply[A](xs: LazyList[A]): Option[(A, LazyList[A])] = #::.unapply(xs) + } + + implicit def toDeferrer[A](l: => LazyList[A]): Deferrer[A] = new Deferrer[A](() => l) + + final class Deferrer[A] private[LazyList] (private val l: () => LazyList[A]) extends AnyVal { + /** Construct a LazyList consisting of a given first element followed by elements + * from another LazyList. + */ + def #:: [B >: A](elem: => B): LazyList[B] = newLL(sCons(elem, newLL(l().state))) + /** Construct a LazyList consisting of the concatenation of the given LazyList and + * another LazyList. + */ + def #:::[B >: A](prefix: LazyList[B]): LazyList[B] = prefix lazyAppendedAll l() + } + + object #:: { + def unapply[A](s: LazyList[A]): Option[(A, LazyList[A])] = + if (!s.isEmpty) Some((s.head, s.tail)) else None + } + + def from[A](coll: collection.IterableOnce[A]): LazyList[A] = coll match { + case lazyList: LazyList[A] => lazyList + case _ if coll.knownSize == 0 => empty[A] + case _ => newLL(stateFromIterator(coll.iterator)) + } + + def empty[A]: LazyList[A] = _empty + + /** Creates a State from an Iterator, with another State appended after the Iterator + * is empty. + */ + private def stateFromIteratorConcatSuffix[A](it: Iterator[A])(suffix: => State[A]): State[A] = + if (it.hasNext) sCons(it.next(), newLL(stateFromIteratorConcatSuffix(it)(suffix))) + else suffix + + /** Creates a State from an IterableOnce. */ + private def stateFromIterator[A](it: Iterator[A]): State[A] = + if (it.hasNext) sCons(it.next(), newLL(stateFromIterator(it))) + else State.Empty + + override def concat[A](xss: collection.Iterable[A]*): LazyList[A] = + if (xss.knownSize == 0) empty + else newLL(concatIterator(xss.iterator)) + + private def concatIterator[A](it: Iterator[collection.Iterable[A]]): State[A] = + if (!it.hasNext) State.Empty + else stateFromIteratorConcatSuffix(it.next().iterator)(concatIterator(it)) + + /** An infinite LazyList that repeatedly applies a given function to a start value. + * + * @param start the start value of the LazyList + * @param f the function that's repeatedly applied + * @return the LazyList returning the infinite sequence of values `start, f(start), f(f(start)), ...` + */ + def iterate[A](start: => A)(f: A => A): LazyList[A] = + newLL { + val head = start + sCons(head, iterate(f(head))(f)) + } + + /** + * Create an infinite LazyList starting at `start` and incrementing by + * step `step`. + * + * @param start the start value of the LazyList + * @param step the increment value of the LazyList + * @return the LazyList starting at value `start`. + */ + def from(start: Int, step: Int): LazyList[Int] = + newLL(sCons(start, from(start + step, step))) + + /** + * Create an infinite LazyList starting at `start` and incrementing by `1`. + * + * @param start the start value of the LazyList + * @return the LazyList starting at value `start`. + */ + def from(start: Int): LazyList[Int] = from(start, 1) + + /** + * Create an infinite LazyList containing the given element expression (which + * is computed for each occurrence). + * + * @param elem the element composing the resulting LazyList + * @return the LazyList containing an infinite number of elem + */ + def continually[A](elem: => A): LazyList[A] = newLL(sCons(elem, continually(elem))) + + override def fill[A](n: Int)(elem: => A): LazyList[A] = + if (n > 0) newLL(sCons(elem, fill(n - 1)(elem))) else empty + + override def tabulate[A](n: Int)(f: Int => A): LazyList[A] = { + def at(index: Int): LazyList[A] = + if (index < n) newLL(sCons(f(index), at(index + 1))) else empty + + at(0) + } + + // significantly simpler than the iterator returned by Iterator.unfold + override def unfold[A, S](init: S)(f: S => Option[(A, S)]): LazyList[A] = + newLL { + f(init) match { + case Some((elem, state)) => sCons(elem, unfold(state)(f)) + case None => State.Empty + } + } + + /** The builder returned by this method only evaluates elements + * of collections added to it as needed. + * + * @tparam A the type of the ${coll}’s elements + * @return A builder for $Coll objects. + */ + def newBuilder[A]: Builder[A, LazyList[A]] = new LazyBuilder[A] + + private class LazyIterator[+A](private[this] var lazyList: LazyList[A]) extends AbstractIterator[A] { + override def hasNext: Boolean = !lazyList.isEmpty + + override def next(): A = + if (lazyList.isEmpty) Iterator.empty.next() + else { + val res = lazyList.head + lazyList = lazyList.tail + res + } + } + + private class SlidingIterator[A](private[this] var lazyList: LazyList[A], size: Int, step: Int) + extends AbstractIterator[LazyList[A]] { + private val minLen = size - step max 0 + private var first = true + + def hasNext: Boolean = + if (first) !lazyList.isEmpty + else lazyList.lengthGt(minLen) + + def next(): LazyList[A] = { + if (!hasNext) Iterator.empty.next() + else { + first = false + val list = lazyList + lazyList = list.drop(step) + list.take(size) + } + } + } + + private final class WithFilter[A] private[LazyList](lazyList: LazyList[A], p: A => Boolean) + extends collection.WithFilter[A, LazyList] { + private[this] val filtered = lazyList.filter(p) + def map[B](f: A => B): LazyList[B] = filtered.map(f) + def flatMap[B](f: A => IterableOnce[B]): LazyList[B] = filtered.flatMap(f) + def foreach[U](f: A => U): Unit = filtered.foreach(f) + def withFilter(q: A => Boolean): collection.WithFilter[A, LazyList] = new WithFilter(filtered, q) + } + + private final class LazyBuilder[A] extends ReusableBuilder[A, LazyList[A]] { + import LazyBuilder._ + + private[this] var next: DeferredState[A] = _ + private[this] var list: LazyList[A] = _ + + clear() + + override def clear(): Unit = { + val deferred = new DeferredState[A] + list = newLL(deferred.eval()) + next = deferred + } + + override def result(): LazyList[A] = { + next init State.Empty + list + } + + override def addOne(elem: A): this.type = { + val deferred = new DeferredState[A] + next init sCons(elem, newLL(deferred.eval())) + next = deferred + this + } + + // lazy implementation which doesn't evaluate the collection being added + override def addAll(xs: IterableOnce[A]): this.type = { + if (xs.knownSize != 0) { + val deferred = new DeferredState[A] + next init stateFromIteratorConcatSuffix(xs.iterator)(deferred.eval()) + next = deferred + } + this + } + } + + private object LazyBuilder { + final class DeferredState[A] { + private[this] var _state: () => State[A] = _ + + def eval(): State[A] = { + val state = _state + if (state == null) throw new IllegalStateException("uninitialized") + state() + } + + // racy + def init(state: => State[A]): Unit = { + if (_state != null) throw new IllegalStateException("already initialized") + _state = () => state + } + } + } + + /** This serialization proxy is used for LazyLists which start with a sequence of evaluated cons cells. + * The forced sequence is serialized in a compact, sequential format, followed by the unevaluated tail, which uses + * standard Java serialization to store the complete structure of unevaluated thunks. This allows the serialization + * of long evaluated lazy lists without exhausting the stack through recursive serialization of cons cells. + */ + @SerialVersionUID(3L) + final class SerializationProxy[A](@transient protected var coll: LazyList[A]) extends Serializable { + + private[this] def writeObject(out: ObjectOutputStream): Unit = { + out.defaultWriteObject() + var these = coll + while (these.knownNonEmpty) { + out.writeObject(these.head) + these = these.tail + } + out.writeObject(SerializeEnd) + out.writeObject(these) + } + + private[this] def readObject(in: ObjectInputStream): Unit = { + in.defaultReadObject() + val init = new mutable.ListBuffer[A] + var initRead = false + while (!initRead) in.readObject match { + case SerializeEnd => initRead = true + case a => init += a.asInstanceOf[A] + } + val tail = in.readObject().asInstanceOf[LazyList[A]] + // scala/scala#10118: caution that no code path can evaluate `tail.state` + // before the resulting LazyList is returned + val it = init.toList.iterator + coll = newLL(stateFromIteratorConcatSuffix(it)(tail.state)) + } + + private[this] def readResolve(): Any = coll + } +} From bf58e2baea9ba91aebc7186828541020de4a67a5 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 21:43:46 +0100 Subject: [PATCH 78/89] Survive "cannot establish a reference" errors in TreeTypeMap --- compiler/src/dotty/tools/dotc/ast/TreeTypeMap.scala | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/compiler/src/dotty/tools/dotc/ast/TreeTypeMap.scala b/compiler/src/dotty/tools/dotc/ast/TreeTypeMap.scala index 955892b2ae22..d2e18729836b 100644 --- a/compiler/src/dotty/tools/dotc/ast/TreeTypeMap.scala +++ b/compiler/src/dotty/tools/dotc/ast/TreeTypeMap.scala @@ -105,7 +105,8 @@ class TreeTypeMap( tree1.withType(mapType(tree1.tpe)) match { case id: Ident => if needsSelect(id.tpe) then - ref(id.tpe.asInstanceOf[TermRef]).withSpan(id.span) + try ref(id.tpe.asInstanceOf[TermRef]).withSpan(id.span) + catch case ex: TypeError => super.transform(id) else super.transform(id) case sel: Select => From 6ae16a4d125bb87ece95c882c2436397a934b8a8 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 21:47:47 +0100 Subject: [PATCH 79/89] Add checked LazyList to stdlib --- .../collection/immutable/LazyList.scala | 219 +++++++++--------- 1 file changed, 104 insertions(+), 115 deletions(-) diff --git a/tests/pos-special/stdlib/collection/immutable/LazyList.scala b/tests/pos-special/stdlib/collection/immutable/LazyList.scala index 8b7ad26dc5ae..711453d904a6 100644 --- a/tests/pos-special/stdlib/collection/immutable/LazyList.scala +++ b/tests/pos-special/stdlib/collection/immutable/LazyList.scala @@ -22,6 +22,8 @@ import scala.collection.generic.SerializeEnd import scala.collection.mutable.{Builder, ReusableBuilder, StringBuilder} import scala.language.implicitConversions import scala.runtime.Statics +import language.experimental.captureChecking +import annotation.unchecked.uncheckedCaptures /** This class implements an immutable linked list. We call it "lazy" * because it computes its elements only when they are needed. @@ -237,19 +239,20 @@ import scala.runtime.Statics * @define evaluatesAllElements This method evaluates all elements of the collection. */ @SerialVersionUID(3L) -final class LazyList[+A] private(private[this] var lazyState: () => LazyList.State[A]) - extends AbstractSeq[A] - with LinearSeq[A] - with LinearSeqOps[A, LazyList, LazyList[A]] +final class LazyList[+A] private(private[this] var lazyState: () => LazyList.State[A]^) + extends AbstractIterable[A] + with Iterable[A] + with IterableOps[A, LazyList, LazyList[A]] with IterableFactoryDefaults[A, LazyList] with Serializable { + this: LazyList[A]^ => import LazyList._ @volatile private[this] var stateEvaluated: Boolean = false @inline private def stateDefined: Boolean = stateEvaluated private[this] var midEvaluation = false - private lazy val state: State[A] = { + private lazy val state: State[A]^ = { // if it's already mid-evaluation, we're stuck in an infinite // self-referential loop (also it's empty) if (midEvaluation) { @@ -264,7 +267,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta res } - override def iterableFactory: SeqFactory[LazyList] = LazyList + override def iterableFactory: IterableFactory[LazyList] = LazyList override def isEmpty: Boolean = state eq State.Empty @@ -276,7 +279,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta override def head: A = state.head - override def tail: LazyList[A] = state.tail + override def tail: LazyList[A]^{this} = state.tail @inline private[this] def knownIsEmpty: Boolean = stateEvaluated && (isEmpty: @inline) @inline private def knownNonEmpty: Boolean = stateEvaluated && !(isEmpty: @inline) @@ -302,7 +305,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta */ def force: this.type = { // Use standard 2x 1x iterator trick for cycle detection ("those" is slow one) - var these, those: LazyList[A] = this + var these, those: LazyList[A]^{this} = this if (!these.isEmpty) { these = these.tail } @@ -322,7 +325,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * The iterator returned by this method preserves laziness; elements are * only evaluated individually as needed. */ - override def iterator: Iterator[A] = + override def iterator: Iterator[A]^{this} = if (knownIsEmpty) Iterator.empty else new LazyIterator(this) @@ -359,7 +362,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta else tail.foldLeft(op(z, head))(op) // State.Empty doesn't use the SerializationProxy - protected[this] def writeReplace(): AnyRef = + protected[this] def writeReplace(): AnyRef^{this} = if (knownNonEmpty) new LazyList.SerializationProxy[A](this) else this override protected[this] def className = "LazyList" @@ -373,7 +376,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * @param suffix The collection that gets appended to this lazy list * @return The lazy list containing elements of this lazy list and the iterable object. */ - def lazyAppendedAll[B >: A](suffix: => collection.IterableOnce[B]): LazyList[B] = + def lazyAppendedAll[B >: A](suffix: => collection.IterableOnce[B]^): LazyList[B]^{this, suffix} = newLL { if (isEmpty) suffix match { case lazyList: LazyList[B] => lazyList.state // don't recompute the LazyList @@ -389,7 +392,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $appendStackSafety */ - override def appendedAll[B >: A](suffix: IterableOnce[B]): LazyList[B] = + def appendedAll[B >: A](suffix: IterableOnce[B]^): LazyList[B]^{this, suffix} = if (knownIsEmpty) LazyList.from(suffix) else lazyAppendedAll(suffix) @@ -399,7 +402,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $appendStackSafety */ - override def appended[B >: A](elem: B): LazyList[B] = + def appended[B >: A](elem: B): LazyList[B]^{this} = if (knownIsEmpty) newLL(sCons(elem, LazyList.empty)) else lazyAppendedAll(Iterator.single(elem)) @@ -407,11 +410,11 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def scanLeft[B](z: B)(op: (B, A) => B): LazyList[B] = + override def scanLeft[B](z: B)(op: (B, A) => B): LazyList[B]^{this, op} = if (knownIsEmpty) newLL(sCons(z, LazyList.empty)) else newLL(scanLeftState(z)(op)) - private def scanLeftState[B](z: B)(op: (B, A) => B): State[B] = + private def scanLeftState[B](z: B)(op: (B, A) => B): State[B]^{this, op} = sCons( z, newLL { @@ -431,7 +434,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta if (this.isEmpty) throw new UnsupportedOperationException("empty.reduceLeft") else { var reducedRes: B = this.head - var left: LazyList[A] = this.tail + var left: LazyList[A]^{this} = this.tail while (!left.isEmpty) { reducedRes = f(reducedRes, left.head) left = left.tail @@ -444,13 +447,13 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def partition(p: A => Boolean): (LazyList[A], LazyList[A]) = (filter(p), filterNot(p)) + override def partition(p: A => Boolean): (LazyList[A]^{this, p}, LazyList[A]^{this, p}) = (filter(p), filterNot(p)) /** @inheritdoc * * $preservesLaziness */ - override def partitionMap[A1, A2](f: A => Either[A1, A2]): (LazyList[A1], LazyList[A2]) = { + override def partitionMap[A1, A2](f: A => Either[A1, A2]): (LazyList[A1]^{this, f}, LazyList[A2]^{this, f}) = { val (left, right) = map(f).partition(_.isLeft) (left.map(_.asInstanceOf[Left[A1, _]].value), right.map(_.asInstanceOf[Right[_, A2]].value)) } @@ -459,7 +462,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def filter(pred: A => Boolean): LazyList[A] = + override def filter(pred: A => Boolean): LazyList[A]^{this, pred} = if (knownIsEmpty) LazyList.empty else LazyList.filterImpl(this, pred, isFlipped = false) @@ -467,7 +470,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def filterNot(pred: A => Boolean): LazyList[A] = + override def filterNot(pred: A => Boolean): LazyList[A]^{this, pred} = if (knownIsEmpty) LazyList.empty else LazyList.filterImpl(this, pred, isFlipped = true) @@ -479,20 +482,20 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * The `collection.WithFilter` returned by this method preserves laziness; elements are * only evaluated individually as needed. */ - override def withFilter(p: A => Boolean): collection.WithFilter[A, LazyList] = + override def withFilter(p: A => Boolean): collection.WithFilter[A, LazyList]^{this, p} = new LazyList.WithFilter(coll, p) /** @inheritdoc * * $preservesLaziness */ - override def prepended[B >: A](elem: B): LazyList[B] = newLL(sCons(elem, this)) + def prepended[B >: A](elem: B): LazyList[B] = newLL(sCons(elem, this)) /** @inheritdoc * * $preservesLaziness */ - override def prependedAll[B >: A](prefix: collection.IterableOnce[B]): LazyList[B] = + def prependedAll[B >: A](prefix: collection.IterableOnce[B]^): LazyList[B]^{this, prefix} = if (knownIsEmpty) LazyList.from(prefix) else if (prefix.knownSize == 0) this else newLL(stateFromIteratorConcatSuffix(prefix.iterator)(state)) @@ -501,7 +504,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def map[B](f: A => B): LazyList[B] = + override def map[B](f: A => B): LazyList[B]^{this, f} = if (knownIsEmpty) LazyList.empty else (mapImpl(f): @inline) @@ -509,9 +512,9 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def tapEach[U](f: A => U): LazyList[A] = map { a => f(a); a } + override def tapEach[U](f: A => U): LazyList[A]^{this, f} = map { a => f(a); a } - private def mapImpl[B](f: A => B): LazyList[B] = + private def mapImpl[B](f: A => B): LazyList[B]^{this, f} = newLL { if (isEmpty) State.Empty else sCons(f(head), tail.mapImpl(f)) @@ -521,7 +524,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def collect[B](pf: PartialFunction[A, B]): LazyList[B] = + override def collect[B](pf: PartialFunction[A, B]^): LazyList[B]^{this, pf} = if (knownIsEmpty) LazyList.empty else LazyList.collectImpl(this, pf) @@ -559,7 +562,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta */ // optimisations are not for speed, but for functionality // see tickets #153, #498, #2147, and corresponding tests in run/ (as well as run/stream_flatmap_odds.scala) - override def flatMap[B](f: A => IterableOnce[B]): LazyList[B] = + override def flatMap[B](f: A => IterableOnce[B]^): LazyList[B]^{this, f} = if (knownIsEmpty) LazyList.empty else LazyList.flatMapImpl(this, f) @@ -567,17 +570,17 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def flatten[B](implicit asIterable: A => IterableOnce[B]): LazyList[B] = flatMap(asIterable) + override def flatten[B](implicit asIterable: A -> IterableOnce[B]): LazyList[B]^{this} = flatMap(asIterable) /** @inheritdoc * * $preservesLaziness */ - override def zip[B](that: collection.IterableOnce[B]): LazyList[(A, B)] = + override def zip[B](that: collection.IterableOnce[B]^): LazyList[(A, B)]^{this, that} = if (this.knownIsEmpty || that.knownSize == 0) LazyList.empty else newLL(zipState(that.iterator)) - private def zipState[B](it: Iterator[B]): State[(A, B)] = + private def zipState[B](it: Iterator[B]^): State[(A, B)]^{this, it} = if (this.isEmpty || !it.hasNext) State.Empty else sCons((head, it.next()), newLL { tail zipState it }) @@ -585,13 +588,13 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def zipWithIndex: LazyList[(A, Int)] = this zip LazyList.from(0) + override def zipWithIndex: LazyList[(A, Int)]^{this} = this zip LazyList.from(0) /** @inheritdoc * * $preservesLaziness */ - override def zipAll[A1 >: A, B](that: collection.Iterable[B], thisElem: A1, thatElem: B): LazyList[(A1, B)] = { + override def zipAll[A1 >: A, B](that: collection.Iterable[B]^, thisElem: A1, thatElem: B): LazyList[(A1, B)]^{this, that} = { if (this.knownIsEmpty) { if (that.knownSize == 0) LazyList.empty else LazyList.continually(thisElem) zip that @@ -601,7 +604,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta } } - private def zipAllState[A1 >: A, B](it: Iterator[B], thisElem: A1, thatElem: B): State[(A1, B)] = { + private def zipAllState[A1 >: A, B](it: Iterator[B]^, thisElem: A1, thatElem: B): State[(A1, B)]^{this, it} = { if (it.hasNext) { if (this.isEmpty) sCons((thisElem, it.next()), newLL { LazyList.continually(thisElem) zipState it }) else sCons((this.head, it.next()), newLL { this.tail.zipAllState(it, thisElem, thatElem) }) @@ -620,21 +623,21 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * only evaluated individually as needed. */ // just in case it can be meaningfully overridden at some point - override def lazyZip[B](that: collection.Iterable[B]): LazyZip2[A, B, LazyList.this.type] = + override def lazyZip[B](that: collection.Iterable[B]^): LazyZip2[A, B, LazyList.this.type]^{this, that} = super.lazyZip(that) /** @inheritdoc * * $preservesLaziness */ - override def unzip[A1, A2](implicit asPair: A => (A1, A2)): (LazyList[A1], LazyList[A2]) = + override def unzip[A1, A2](implicit asPair: A -> (A1, A2)): (LazyList[A1]^{this}, LazyList[A2]^{this}) = (map(asPair(_)._1), map(asPair(_)._2)) /** @inheritdoc * * $preservesLaziness */ - override def unzip3[A1, A2, A3](implicit asTriple: A => (A1, A2, A3)): (LazyList[A1], LazyList[A2], LazyList[A3]) = + override def unzip3[A1, A2, A3](implicit asTriple: A -> (A1, A2, A3)): (LazyList[A1]^{this}, LazyList[A2]^{this}, LazyList[A3]^{this}) = (map(asTriple(_)._1), map(asTriple(_)._2), map(asTriple(_)._3)) /** @inheritdoc @@ -642,7 +645,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * $initiallyLazy * Additionally, it preserves laziness for all except the first `n` elements. */ - override def drop(n: Int): LazyList[A] = + override def drop(n: Int): LazyList[A]^{this} = if (n <= 0) this else if (knownIsEmpty) LazyList.empty else LazyList.dropImpl(this, n) @@ -652,7 +655,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * $initiallyLazy * Additionally, it preserves laziness for all elements after the predicate returns `false`. */ - override def dropWhile(p: A => Boolean): LazyList[A] = + override def dropWhile(p: A => Boolean): LazyList[A]^{this, p} = if (knownIsEmpty) LazyList.empty else LazyList.dropWhileImpl(this, p) @@ -660,7 +663,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $initiallyLazy */ - override def dropRight(n: Int): LazyList[A] = { + override def dropRight(n: Int): LazyList[A]^{this} = { if (n <= 0) this else if (knownIsEmpty) LazyList.empty else newLL { @@ -675,7 +678,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta } } - private def dropRightState(scout: LazyList[_]): State[A] = + private def dropRightState(scout: LazyList[_]^): State[A]^{this, scout} = if (scout.isEmpty) State.Empty else sCons(head, newLL(tail.dropRightState(scout.tail))) @@ -699,11 +702,11 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def takeWhile(p: A => Boolean): LazyList[A] = + override def takeWhile(p: A => Boolean): LazyList[A]^{this, p} = if (knownIsEmpty) LazyList.empty else (takeWhileImpl(p): @inline) - private def takeWhileImpl(p: A => Boolean): LazyList[A] = + private def takeWhileImpl(p: A => Boolean): LazyList[A]^{this, p} = newLL { if (isEmpty || !p(head)) State.Empty else sCons(head, tail.takeWhileImpl(p)) @@ -713,7 +716,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $initiallyLazy */ - override def takeRight(n: Int): LazyList[A] = + override def takeRight(n: Int): LazyList[A]^{this} = if (n <= 0 || knownIsEmpty) LazyList.empty else LazyList.takeRightImpl(this, n) @@ -722,13 +725,13 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * $initiallyLazy * Additionally, it preserves laziness for all but the first `from` elements. */ - override def slice(from: Int, until: Int): LazyList[A] = take(until).drop(from) + override def slice(from: Int, until: Int): LazyList[A]^{this} = take(until).drop(from) /** @inheritdoc * * $evaluatesAllElements */ - override def reverse: LazyList[A] = reverseOnto(LazyList.empty) + def reverse: LazyList[A] = reverseOnto(LazyList.empty) // need contravariant type B to make the compiler happy - still returns LazyList[A] @tailrec @@ -736,22 +739,6 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta if (isEmpty) tl else tail.reverseOnto(newLL(sCons(head, tl))) - /** @inheritdoc - * - * $preservesLaziness - */ - override def diff[B >: A](that: collection.Seq[B]): LazyList[A] = - if (knownIsEmpty) LazyList.empty - else super.diff(that) - - /** @inheritdoc - * - * $preservesLaziness - */ - override def intersect[B >: A](that: collection.Seq[B]): LazyList[A] = - if (knownIsEmpty) LazyList.empty - else super.intersect(that) - @tailrec private def lengthGt(len: Int): Boolean = if (len < 0) true @@ -786,7 +773,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def padTo[B >: A](len: Int, elem: B): LazyList[B] = { + def padTo[B >: A](len: Int, elem: B): LazyList[B]^{this} = { if (len <= 0) this else newLL { if (isEmpty) LazyList.fill(len)(elem).state @@ -798,11 +785,11 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def patch[B >: A](from: Int, other: IterableOnce[B], replaced: Int): LazyList[B] = + def patch[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): LazyList[B]^{this, other} = if (knownIsEmpty) LazyList from other else patchImpl(from, other, replaced) - private def patchImpl[B >: A](from: Int, other: IterableOnce[B], replaced: Int): LazyList[B] = + private def patchImpl[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): LazyList[B]^{this, other} = newLL { if (from <= 0) stateFromIteratorConcatSuffix(other.iterator)(LazyList.dropImpl(this, replaced).state) else if (isEmpty) stateFromIterator(other.iterator) @@ -814,17 +801,17 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * $evaluatesAllElements */ // overridden just in case a lazy implementation is developed at some point - override def transpose[B](implicit asIterable: A => collection.Iterable[B]): LazyList[LazyList[B]] = super.transpose + override def transpose[B](implicit asIterable: A -> collection.Iterable[B]): LazyList[LazyList[B]]^{this} = super.transpose /** @inheritdoc * * $preservesLaziness */ - override def updated[B >: A](index: Int, elem: B): LazyList[B] = + def updated[B >: A](index: Int, elem: B): LazyList[B]^{this} = if (index < 0) throw new IndexOutOfBoundsException(s"$index") else updatedImpl(index, elem, index) - private def updatedImpl[B >: A](index: Int, elem: B, startIndex: Int): LazyList[B] = { + private def updatedImpl[B >: A](index: Int, elem: B, startIndex: Int): LazyList[B]^{this} = { newLL { if (index <= 0) sCons(elem, tail) else if (tail.isEmpty) throw new IndexOutOfBoundsException(startIndex.toString) @@ -883,7 +870,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta // if cursor (eq scout) has state defined, it is empty; else unknown state if (!cursor.stateDefined) b.append(sep).append("") } else { - @inline def same(a: LazyList[A], b: LazyList[A]): Boolean = (a eq b) || (a.state eq b.state) + @inline def same(a: LazyList[A]^, b: LazyList[A]^): Boolean = (a eq b) || (a.state eq b.state) // Cycle. // If we have a prefix of length P followed by a cycle of length C, // the scout will be at position (P%C) in the cycle when the cursor @@ -966,13 +953,14 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * @define Coll `LazyList` */ @SerialVersionUID(3L) -object LazyList extends SeqFactory[LazyList] { +object LazyList extends IterableFactory[LazyList] { // Eagerly evaluate cached empty instance private[this] val _empty = newLL(State.Empty).force private sealed trait State[+A] extends Serializable { + this: State[A]^ => def head: A - def tail: LazyList[A] + def tail: LazyList[A]^ } private object State { @@ -983,14 +971,14 @@ object LazyList extends SeqFactory[LazyList] { } @SerialVersionUID(3L) - final class Cons[A](val head: A, val tail: LazyList[A]) extends State[A] + final class Cons[A](val head: A, val tail: LazyList[A]^) extends State[A] } /** Creates a new LazyList. */ - @inline private def newLL[A](state: => State[A]): LazyList[A] = new LazyList[A](() => state) + @inline private def newLL[A](state: => State[A]^): LazyList[A]^{state} = new LazyList[A](() => state) /** Creates a new State.Cons. */ - @inline private def sCons[A](hd: A, tl: LazyList[A]): State[A] = new State.Cons[A](hd, tl) + @inline private def sCons[A](hd: A, tl: LazyList[A]^): State[A]^{tl} = new State.Cons[A](hd, tl) private val anyToMarker: Any => Any = _ => Statics.pfMarker @@ -1002,7 +990,7 @@ object LazyList extends SeqFactory[LazyList] { * can continue their execution where they left off. */ - private def filterImpl[A](ll: LazyList[A], p: A => Boolean, isFlipped: Boolean): LazyList[A] = { + private def filterImpl[A](ll: LazyList[A]^, p: A => Boolean, isFlipped: Boolean): LazyList[A]^{ll, p} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1019,7 +1007,7 @@ object LazyList extends SeqFactory[LazyList] { } } - private def collectImpl[A, B](ll: LazyList[A], pf: PartialFunction[A, B]): LazyList[B] = { + private def collectImpl[A, B](ll: LazyList[A]^, pf: PartialFunction[A, B]^): LazyList[B]^{ll, pf} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1038,11 +1026,11 @@ object LazyList extends SeqFactory[LazyList] { } } - private def flatMapImpl[A, B](ll: LazyList[A], f: A => IterableOnce[B]): LazyList[B] = { + private def flatMapImpl[A, B](ll: LazyList[A]^, f: A => IterableOnce[B]^): LazyList[B]^{ll, f} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { - var it: Iterator[B] = null + var it: Iterator[B]^{ll, f} = null var itHasNext = false var rest = restRef // var rest = restRef.elem while (!itHasNext && !rest.isEmpty) { @@ -1062,7 +1050,7 @@ object LazyList extends SeqFactory[LazyList] { } } - private def dropImpl[A](ll: LazyList[A], n: Int): LazyList[A] = { + private def dropImpl[A](ll: LazyList[A]^, n: Int): LazyList[A]^{ll} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) var iRef = n // val iRef = new IntRef(n) @@ -1079,7 +1067,7 @@ object LazyList extends SeqFactory[LazyList] { } } - private def dropWhileImpl[A](ll: LazyList[A], p: A => Boolean): LazyList[A] = { + private def dropWhileImpl[A](ll: LazyList[A]^, p: A => Boolean): LazyList[A]^{ll, p} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1092,7 +1080,7 @@ object LazyList extends SeqFactory[LazyList] { } } - private def takeRightImpl[A](ll: LazyList[A], n: Int): LazyList[A] = { + private def takeRightImpl[A](ll: LazyList[A]^, n: Int): LazyList[A]^{ll} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) var scoutRef = ll // val scoutRef = new ObjectRef(ll) @@ -1127,31 +1115,29 @@ object LazyList extends SeqFactory[LazyList] { * @param hd The first element of the result lazy list * @param tl The remaining elements of the result lazy list */ - def apply[A](hd: => A, tl: => LazyList[A]): LazyList[A] = newLL(sCons(hd, newLL(tl.state))) + def apply[A](hd: => A, tl: => LazyList[A]^): LazyList[A]^{hd, tl} = newLL(sCons(hd, newLL(tl.state))) /** Maps a lazy list to its head and tail */ - def unapply[A](xs: LazyList[A]): Option[(A, LazyList[A])] = #::.unapply(xs) + def unapply[A](xs: LazyList[A]^): Option[(A, LazyList[A]^{xs})] = #::.unapply(xs) } - implicit def toDeferrer[A](l: => LazyList[A]): Deferrer[A] = new Deferrer[A](() => l) - - final class Deferrer[A] private[LazyList] (private val l: () => LazyList[A]) extends AnyVal { + extension [A](l: => LazyList[A]) /** Construct a LazyList consisting of a given first element followed by elements * from another LazyList. */ - def #:: [B >: A](elem: => B): LazyList[B] = newLL(sCons(elem, newLL(l().state))) + def #:: [B >: A](elem: => B): LazyList[B]^{elem, l} = newLL(sCons(elem, newLL(l.state))) + /** Construct a LazyList consisting of the concatenation of the given LazyList and * another LazyList. */ - def #:::[B >: A](prefix: LazyList[B]): LazyList[B] = prefix lazyAppendedAll l() - } + def #:::[B >: A](prefix: LazyList[B]^): LazyList[B]^{prefix, l} = prefix lazyAppendedAll l object #:: { - def unapply[A](s: LazyList[A]): Option[(A, LazyList[A])] = + def unapply[A](s: LazyList[A]^): Option[(A, LazyList[A]^{s})] = if (!s.isEmpty) Some((s.head, s.tail)) else None } - def from[A](coll: collection.IterableOnce[A]): LazyList[A] = coll match { + def from[A](coll: collection.IterableOnce[A]^): LazyList[A]^{coll} = coll match { case lazyList: LazyList[A] => lazyList case _ if coll.knownSize == 0 => empty[A] case _ => newLL(stateFromIterator(coll.iterator)) @@ -1162,12 +1148,12 @@ object LazyList extends SeqFactory[LazyList] { /** Creates a State from an Iterator, with another State appended after the Iterator * is empty. */ - private def stateFromIteratorConcatSuffix[A](it: Iterator[A])(suffix: => State[A]): State[A] = + private def stateFromIteratorConcatSuffix[A](it: Iterator[A]^)(suffix: => State[A]^): State[A]^{it, suffix} = if (it.hasNext) sCons(it.next(), newLL(stateFromIteratorConcatSuffix(it)(suffix))) else suffix /** Creates a State from an IterableOnce. */ - private def stateFromIterator[A](it: Iterator[A]): State[A] = + private def stateFromIterator[A](it: Iterator[A]^): State[A]^{it} = if (it.hasNext) sCons(it.next(), newLL(stateFromIterator(it))) else State.Empty @@ -1175,7 +1161,7 @@ object LazyList extends SeqFactory[LazyList] { if (xss.knownSize == 0) empty else newLL(concatIterator(xss.iterator)) - private def concatIterator[A](it: Iterator[collection.Iterable[A]]): State[A] = + private def concatIterator[A](it: Iterator[collection.Iterable[A]]^): State[A]^{it} = if (!it.hasNext) State.Empty else stateFromIteratorConcatSuffix(it.next().iterator)(concatIterator(it)) @@ -1185,7 +1171,7 @@ object LazyList extends SeqFactory[LazyList] { * @param f the function that's repeatedly applied * @return the LazyList returning the infinite sequence of values `start, f(start), f(f(start)), ...` */ - def iterate[A](start: => A)(f: A => A): LazyList[A] = + def iterate[A](start: => A)(f: A => A): LazyList[A]^{start, f} = newLL { val head = start sCons(head, iterate(f(head))(f)) @@ -1217,20 +1203,20 @@ object LazyList extends SeqFactory[LazyList] { * @param elem the element composing the resulting LazyList * @return the LazyList containing an infinite number of elem */ - def continually[A](elem: => A): LazyList[A] = newLL(sCons(elem, continually(elem))) + def continually[A](elem: => A): LazyList[A]^{elem} = newLL(sCons(elem, continually(elem))) - override def fill[A](n: Int)(elem: => A): LazyList[A] = + override def fill[A](n: Int)(elem: => A): LazyList[A]^{elem} = if (n > 0) newLL(sCons(elem, fill(n - 1)(elem))) else empty - override def tabulate[A](n: Int)(f: Int => A): LazyList[A] = { - def at(index: Int): LazyList[A] = + override def tabulate[A](n: Int)(f: Int => A): LazyList[A]^{f} = { + def at(index: Int): LazyList[A]^{f} = if (index < n) newLL(sCons(f(index), at(index + 1))) else empty at(0) } // significantly simpler than the iterator returned by Iterator.unfold - override def unfold[A, S](init: S)(f: S => Option[(A, S)]): LazyList[A] = + override def unfold[A, S](init: S)(f: S => Option[(A, S)]): LazyList[A]^{f} = newLL { f(init) match { case Some((elem, state)) => sCons(elem, unfold(state)(f)) @@ -1246,7 +1232,7 @@ object LazyList extends SeqFactory[LazyList] { */ def newBuilder[A]: Builder[A, LazyList[A]] = new LazyBuilder[A] - private class LazyIterator[+A](private[this] var lazyList: LazyList[A]) extends AbstractIterator[A] { + private class LazyIterator[+A](private[this] var lazyList: LazyList[A]^) extends AbstractIterator[A] { override def hasNext: Boolean = !lazyList.isEmpty override def next(): A = @@ -1258,8 +1244,9 @@ object LazyList extends SeqFactory[LazyList] { } } - private class SlidingIterator[A](private[this] var lazyList: LazyList[A], size: Int, step: Int) + private class SlidingIterator[A](private[this] var lazyList: LazyList[A]^, size: Int, step: Int) extends AbstractIterator[LazyList[A]] { + this: SlidingIterator[A]^ => private val minLen = size - step max 0 private var first = true @@ -1278,20 +1265,21 @@ object LazyList extends SeqFactory[LazyList] { } } - private final class WithFilter[A] private[LazyList](lazyList: LazyList[A], p: A => Boolean) + private final class WithFilter[A] private[LazyList](lazyList: LazyList[A]^, p: A => Boolean) extends collection.WithFilter[A, LazyList] { + this: WithFilter[A]^ => private[this] val filtered = lazyList.filter(p) - def map[B](f: A => B): LazyList[B] = filtered.map(f) - def flatMap[B](f: A => IterableOnce[B]): LazyList[B] = filtered.flatMap(f) + def map[B](f: A => B): LazyList[B]^{this, f} = filtered.map(f) + def flatMap[B](f: A => IterableOnce[B]^): LazyList[B]^{this, f} = filtered.flatMap(f) def foreach[U](f: A => U): Unit = filtered.foreach(f) - def withFilter(q: A => Boolean): collection.WithFilter[A, LazyList] = new WithFilter(filtered, q) + def withFilter(q: A => Boolean): collection.WithFilter[A, LazyList]^{this, q} = new WithFilter(filtered, q) } private final class LazyBuilder[A] extends ReusableBuilder[A, LazyList[A]] { import LazyBuilder._ - private[this] var next: DeferredState[A] = _ - private[this] var list: LazyList[A] = _ + private[this] var next: DeferredState[A @uncheckedCaptures] = _ + private[this] var list: LazyList[A @uncheckedCaptures] = _ clear() @@ -1314,10 +1302,10 @@ object LazyList extends SeqFactory[LazyList] { } // lazy implementation which doesn't evaluate the collection being added - override def addAll(xs: IterableOnce[A]): this.type = { + override def addAll(xs: IterableOnce[A]^): this.type = { if (xs.knownSize != 0) { val deferred = new DeferredState[A] - next init stateFromIteratorConcatSuffix(xs.iterator)(deferred.eval()) + next.init(stateFromIteratorConcatSuffix(xs.iterator)(deferred.eval())) next = deferred } this @@ -1326,16 +1314,17 @@ object LazyList extends SeqFactory[LazyList] { private object LazyBuilder { final class DeferredState[A] { - private[this] var _state: () => State[A] = _ + this: DeferredState[A]^ => + private[this] var _state: (() => State[A]^) @uncheckedCaptures = _ - def eval(): State[A] = { + def eval(): State[A]^ = { val state = _state if (state == null) throw new IllegalStateException("uninitialized") state() } // racy - def init(state: => State[A]): Unit = { + def init(state: => State[A]^): Unit = { if (_state != null) throw new IllegalStateException("already initialized") _state = () => state } @@ -1348,7 +1337,7 @@ object LazyList extends SeqFactory[LazyList] { * of long evaluated lazy lists without exhausting the stack through recursive serialization of cons cells. */ @SerialVersionUID(3L) - final class SerializationProxy[A](@transient protected var coll: LazyList[A]) extends Serializable { + final class SerializationProxy[A](@transient protected var coll: LazyList[A]^) extends Serializable { private[this] def writeObject(out: ObjectOutputStream): Unit = { out.defaultWriteObject() @@ -1363,7 +1352,7 @@ object LazyList extends SeqFactory[LazyList] { private[this] def readObject(in: ObjectInputStream): Unit = { in.defaultReadObject() - val init = new mutable.ListBuffer[A] + val init = new mutable.ListBuffer[A @uncheckedCaptures] var initRead = false while (!initRead) in.readObject match { case SerializeEnd => initRead = true From 0acfb8c0047aacbe69bb14f1ce406ad017471051 Mon Sep 17 00:00:00 2001 From: odersky Date: Thu, 2 Nov 2023 21:54:43 +0100 Subject: [PATCH 80/89] Rename LazyList to LazyListIterable --- .../immutable/{LazyList.scala => LazyListIterable.scala} | 0 1 file changed, 0 insertions(+), 0 deletions(-) rename tests/pos-special/stdlib/collection/immutable/{LazyList.scala => LazyListIterable.scala} (100%) diff --git a/tests/pos-special/stdlib/collection/immutable/LazyList.scala b/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala similarity index 100% rename from tests/pos-special/stdlib/collection/immutable/LazyList.scala rename to tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala From fd88dc1d9bf0c8e7460b0f212e7c9571128fdffb Mon Sep 17 00:00:00 2001 From: odersky Date: Fri, 3 Nov 2023 10:43:21 +0100 Subject: [PATCH 81/89] Allow deep subtypes when compiling stdlib test --- .../dotty/tools/dotc/CompilationTests.scala | 2 +- .../immutable/LazyListIterable.scala | 418 +++++++++--------- 2 files changed, 213 insertions(+), 207 deletions(-) diff --git a/compiler/test/dotty/tools/dotc/CompilationTests.scala b/compiler/test/dotty/tools/dotc/CompilationTests.scala index 798e998ef241..fa89c82fc7e7 100644 --- a/compiler/test/dotty/tools/dotc/CompilationTests.scala +++ b/compiler/test/dotty/tools/dotc/CompilationTests.scala @@ -44,7 +44,7 @@ class CompilationTests { // Run tests for legacy lazy vals compileFilesInDir("tests/pos", defaultOptions.and("-Ysafe-init", "-Ylegacy-lazy-vals", "-Ycheck-constraint-deps"), FileFilter.include(TestSources.posLazyValsAllowlist)), compileDir("tests/pos-special/java-param-names", defaultOptions.withJavacOnlyOptions("-parameters")), - compileDir("tests/pos-special/stdlib", defaultOptions), + compileDir("tests/pos-special/stdlib", allowDeepSubtypes), ) if scala.util.Properties.isJavaAtLeast("16") then diff --git a/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala b/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala index 711453d904a6..8d804bad13de 100644 --- a/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala +++ b/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala @@ -28,17 +28,23 @@ import annotation.unchecked.uncheckedCaptures /** This class implements an immutable linked list. We call it "lazy" * because it computes its elements only when they are needed. * + * The class extends Iterable; it is a replacement for LazyList, which + * which implemented Seq. The reason is that under capture checking, we + * assume that all Seqs are strict, and LazyList broke that assumption. + * As a consequence, we declare LazyList is deprecated and unsafe for + * capture checking, and replace it by the current class, LazyListIterable. + * * Elements are memoized; that is, the value of each element is computed at most once. * * Elements are computed in-order and are never skipped. In other words, * accessing the tail causes the head to be computed first. * - * How lazy is a `LazyList`? When you have a value of type `LazyList`, you + * How lazy is a `LazyListIterable`? When you have a value of type `LazyListIterable`, you * don't know yet whether the list is empty or not. If you learn that it is non-empty, * then you also know that the head has been computed. But the tail is itself - * a `LazyList`, whose emptiness-or-not might remain undetermined. + * a `LazyListIterable`, whose emptiness-or-not might remain undetermined. * - * A `LazyList` may be infinite. For example, `LazyList.from(0)` contains + * A `LazyListIterable` may be infinite. For example, `LazyListIterable.from(0)` contains * all of the natural numbers 0, 1, 2, and so on. For infinite sequences, * some methods (such as `count`, `sum`, `max` or `min`) will not terminate. * @@ -47,7 +53,7 @@ import annotation.unchecked.uncheckedCaptures * {{{ * import scala.math.BigInt * object Main extends App { - * val fibs: LazyList[BigInt] = + * val fibs: LazyListIterable[BigInt] = * BigInt(0) #:: BigInt(1) #:: fibs.zip(fibs.tail).map{ n => n._1 + n._2 } * fibs.take(5).foreach(println) * } @@ -67,7 +73,7 @@ import annotation.unchecked.uncheckedCaptures * {{{ * import scala.math.BigInt * object Main extends App { - * val fibs: LazyList[BigInt] = + * val fibs: LazyListIterable[BigInt] = * BigInt(0) #:: BigInt(1) #:: * fibs.zip(fibs.tail).map{ n => * println(s"Adding \${n._1} and \${n._2}") @@ -100,22 +106,22 @@ import annotation.unchecked.uncheckedCaptures * }}} * * Note that the definition of `fibs` uses `val` not `def`. The memoization of the - * `LazyList` requires us to have somewhere to store the information and a `val` + * `LazyListIterable` requires us to have somewhere to store the information and a `val` * allows us to do that. * - * Further remarks about the semantics of `LazyList`: + * Further remarks about the semantics of `LazyListIterable`: * - * - Though the `LazyList` changes as it is accessed, this does not + * - Though the `LazyListIterable` changes as it is accessed, this does not * contradict its immutability. Once the values are memoized they do * not change. Values that have yet to be memoized still "exist", they * simply haven't been computed yet. * * - One must be cautious of memoization; it can eat up memory if you're not - * careful. That's because memoization of the `LazyList` creates a structure much like + * careful. That's because memoization of the `LazyListIterable` creates a structure much like * [[scala.collection.immutable.List]]. As long as something is holding on to * the head, the head holds on to the tail, and so on recursively. * If, on the other hand, there is nothing holding on to the head (e.g. if we used - * `def` to define the `LazyList`) then once it is no longer being used directly, + * `def` to define the `LazyListIterable`) then once it is no longer being used directly, * it disappears. * * - Note that some operations, including [[drop]], [[dropWhile]], @@ -135,30 +141,30 @@ import annotation.unchecked.uncheckedCaptures * } * } * - * // Our first LazyList definition will be a val definition - * val lazylist1: LazyList[Int] = { - * def loop(v: Int): LazyList[Int] = v #:: loop(v + 1) + * // Our first LazyListIterable definition will be a val definition + * val lazylist1: LazyListIterable[Int] = { + * def loop(v: Int): LazyListIterable[Int] = v #:: loop(v + 1) * loop(0) * } * * // Because lazylist1 is a val, everything that the iterator produces is held - * // by virtue of the fact that the head of the LazyList is held in lazylist1 + * // by virtue of the fact that the head of the LazyListIterable is held in lazylist1 * val it1 = lazylist1.iterator * loop("Iterator1: ", it1.next(), it1) * - * // We can redefine this LazyList such that all we have is the Iterator left - * // and allow the LazyList to be garbage collected as required. Using a def - * // to provide the LazyList ensures that no val is holding onto the head as + * // We can redefine this LazyListIterable such that all we have is the Iterator left + * // and allow the LazyListIterable to be garbage collected as required. Using a def + * // to provide the LazyListIterable ensures that no val is holding onto the head as * // is the case with lazylist1 - * def lazylist2: LazyList[Int] = { - * def loop(v: Int): LazyList[Int] = v #:: loop(v + 1) + * def lazylist2: LazyListIterable[Int] = { + * def loop(v: Int): LazyListIterable[Int] = v #:: loop(v + 1) * loop(0) * } * val it2 = lazylist2.iterator * loop("Iterator2: ", it2.next(), it2) * - * // And, of course, we don't actually need a LazyList at all for such a simple - * // problem. There's no reason to use a LazyList if you don't actually need + * // And, of course, we don't actually need a LazyListIterable at all for such a simple + * // problem. There's no reason to use a LazyListIterable if you don't actually need * // one. * val it3 = new Iterator[Int] { * var i = -1 @@ -169,7 +175,7 @@ import annotation.unchecked.uncheckedCaptures * }}} * * - In the `fibs` example earlier, the fact that `tail` works at all is of interest. - * `fibs` has an initial `(0, 1, LazyList(...))`, so `tail` is deterministic. + * `fibs` has an initial `(0, 1, LazyListIterable(...))`, so `tail` is deterministic. * If we defined `fibs` such that only `0` were concretely known, then the act * of determining `tail` would require the evaluation of `tail`, so the * computation would be unable to progress, as in this code: @@ -177,7 +183,7 @@ import annotation.unchecked.uncheckedCaptures * // The first time we try to access the tail we're going to need more * // information which will require us to recurse, which will require us to * // recurse, which... - * lazy val sov: LazyList[Vector[Int]] = Vector(0) #:: sov.zip(sov.tail).map { n => n._1 ++ n._2 } + * lazy val sov: LazyListIterable[Vector[Int]] = Vector(0) #:: sov.zip(sov.tail).map { n => n._1 ++ n._2 } * }}} * * The definition of `fibs` above creates a larger number of objects than @@ -186,8 +192,8 @@ import annotation.unchecked.uncheckedCaptures * fact that it has a more direct route to the numbers themselves: * * {{{ - * lazy val fib: LazyList[Int] = { - * def loop(h: Int, n: Int): LazyList[Int] = h #:: loop(n, h + n) + * lazy val fib: LazyListIterable[Int] = { + * def loop(h: Int, n: Int): LazyListIterable[Int] = h #:: loop(n, h + n) * loop(1, 1) * } * }}} @@ -198,8 +204,8 @@ import annotation.unchecked.uncheckedCaptures * the tails content is deferred until the tails empty status, head or tail is * evaluated. * - * Delaying the evaluation of whether a LazyList is empty or not until it's needed - * allows LazyList to not eagerly evaluate any elements on a call to `filter`. + * Delaying the evaluation of whether a LazyListIterable is empty or not until it's needed + * allows LazyListIterable to not eagerly evaluate any elements on a call to `filter`. * * Only when it's further evaluated (which may be never!) any of the elements gets * forced. @@ -207,24 +213,24 @@ import annotation.unchecked.uncheckedCaptures * for example: * * {{{ - * def tailWithSideEffect: LazyList[Nothing] = { - * println("getting empty LazyList") - * LazyList.empty + * def tailWithSideEffect: LazyListIterable[Nothing] = { + * println("getting empty LazyListIterable") + * LazyListIterable.empty * } * - * val emptyTail = tailWithSideEffect // prints "getting empty LazyList" + * val emptyTail = tailWithSideEffect // prints "getting empty LazyListIterable" * * val suspended = 1 #:: tailWithSideEffect // doesn't print anything * val tail = suspended.tail // although the tail is evaluated, *still* nothing is yet printed * val filtered = tail.filter(_ => false) // still nothing is printed - * filtered.isEmpty // prints "getting empty LazyList" + * filtered.isEmpty // prints "getting empty LazyListIterable" * }}} * * @tparam A the type of the elements contained in this lazy list. * * @see [[https://docs.scala-lang.org/overviews/collections-2.13/concrete-immutable-collection-classes.html#lazylists "Scala's Collection Library overview"]] * section on `LazyLists` for more information. - * @define Coll `LazyList` + * @define Coll `LazyListIterable` * @define coll lazy list * @define orderDependent * @define orderDependentFold @@ -239,14 +245,14 @@ import annotation.unchecked.uncheckedCaptures * @define evaluatesAllElements This method evaluates all elements of the collection. */ @SerialVersionUID(3L) -final class LazyList[+A] private(private[this] var lazyState: () => LazyList.State[A]^) +final class LazyListIterable[+A] private(private[this] var lazyState: () => LazyListIterable.State[A]^) extends AbstractIterable[A] with Iterable[A] - with IterableOps[A, LazyList, LazyList[A]] - with IterableFactoryDefaults[A, LazyList] + with IterableOps[A, LazyListIterable, LazyListIterable[A]] + with IterableFactoryDefaults[A, LazyListIterable] with Serializable { - this: LazyList[A]^ => - import LazyList._ + this: LazyListIterable[A]^ => + import LazyListIterable._ @volatile private[this] var stateEvaluated: Boolean = false @inline private def stateDefined: Boolean = stateEvaluated @@ -256,7 +262,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta // if it's already mid-evaluation, we're stuck in an infinite // self-referential loop (also it's empty) if (midEvaluation) { - throw new RuntimeException("self-referential LazyList or a derivation thereof has no more elements") + throw new RuntimeException("self-referential LazyListIterable or a derivation thereof has no more elements") } midEvaluation = true val res = try lazyState() finally midEvaluation = false @@ -267,7 +273,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta res } - override def iterableFactory: IterableFactory[LazyList] = LazyList + override def iterableFactory: IterableFactory[LazyListIterable] = LazyListIterable override def isEmpty: Boolean = state eq State.Empty @@ -279,7 +285,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta override def head: A = state.head - override def tail: LazyList[A]^{this} = state.tail + override def tail: LazyListIterable[A]^{this} = state.tail @inline private[this] def knownIsEmpty: Boolean = stateEvaluated && (isEmpty: @inline) @inline private def knownNonEmpty: Boolean = stateEvaluated && !(isEmpty: @inline) @@ -290,13 +296,13 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * elements of the cycle are evaluated. For example: * * {{{ - * val ring: LazyList[Int] = 1 #:: 2 #:: 3 #:: ring + * val ring: LazyListIterable[Int] = 1 #:: 2 #:: 3 #:: ring * ring.force * ring.toString * * // prints * // - * // LazyList(1, 2, 3, ...) + * // LazyListIterable(1, 2, 3, ...) * }}} * * This method will *not* terminate for non-cyclic infinite-sized collections. @@ -305,7 +311,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta */ def force: this.type = { // Use standard 2x 1x iterator trick for cycle detection ("those" is slow one) - var these, those: LazyList[A]^{this} = this + var these, those: LazyListIterable[A]^{this} = this if (!these.isEmpty) { these = these.tail } @@ -335,9 +341,9 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * @param f The treatment to apply to each element. * @note Overridden here as final to trigger tail-call optimization, which * replaces 'this' with 'tail' at each iteration. This is absolutely - * necessary for allowing the GC to collect the underlying LazyList as elements + * necessary for allowing the GC to collect the underlying LazyListIterable as elements * are consumed. - * @note This function will force the realization of the entire LazyList + * @note This function will force the realization of the entire LazyListIterable * unless the `f` throws an exception. */ @tailrec @@ -348,12 +354,12 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta } } - /** LazyList specialization of foldLeft which allows GC to collect along the + /** LazyListIterable specialization of foldLeft which allows GC to collect along the * way. * * @tparam B The type of value being accumulated. * @param z The initial value seeded into the function `op`. - * @param op The operation to perform on successive elements of the `LazyList`. + * @param op The operation to perform on successive elements of the `LazyListIterable`. * @return The accumulated value from successive applications of `op`. */ @tailrec @@ -363,9 +369,9 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta // State.Empty doesn't use the SerializationProxy protected[this] def writeReplace(): AnyRef^{this} = - if (knownNonEmpty) new LazyList.SerializationProxy[A](this) else this + if (knownNonEmpty) new LazyListIterable.SerializationProxy[A](this) else this - override protected[this] def className = "LazyList" + override protected[this] def className = "LazyListIterable" /** The lazy list resulting from the concatenation of this lazy list with the argument lazy list. * @@ -376,10 +382,10 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * @param suffix The collection that gets appended to this lazy list * @return The lazy list containing elements of this lazy list and the iterable object. */ - def lazyAppendedAll[B >: A](suffix: => collection.IterableOnce[B]^): LazyList[B]^{this, suffix} = + def lazyAppendedAll[B >: A](suffix: => collection.IterableOnce[B]^): LazyListIterable[B]^{this, suffix} = newLL { if (isEmpty) suffix match { - case lazyList: LazyList[B] => lazyList.state // don't recompute the LazyList + case lazyList: LazyListIterable[B] => lazyList.state // don't recompute the LazyListIterable case coll if coll.knownSize == 0 => State.Empty case coll => stateFromIterator(coll.iterator) } @@ -392,8 +398,8 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $appendStackSafety */ - def appendedAll[B >: A](suffix: IterableOnce[B]^): LazyList[B]^{this, suffix} = - if (knownIsEmpty) LazyList.from(suffix) + def appendedAll[B >: A](suffix: IterableOnce[B]^): LazyListIterable[B]^{this, suffix} = + if (knownIsEmpty) LazyListIterable.from(suffix) else lazyAppendedAll(suffix) /** @inheritdoc @@ -402,16 +408,16 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $appendStackSafety */ - def appended[B >: A](elem: B): LazyList[B]^{this} = - if (knownIsEmpty) newLL(sCons(elem, LazyList.empty)) + def appended[B >: A](elem: B): LazyListIterable[B]^{this} = + if (knownIsEmpty) newLL(sCons(elem, LazyListIterable.empty)) else lazyAppendedAll(Iterator.single(elem)) /** @inheritdoc * * $preservesLaziness */ - override def scanLeft[B](z: B)(op: (B, A) => B): LazyList[B]^{this, op} = - if (knownIsEmpty) newLL(sCons(z, LazyList.empty)) + override def scanLeft[B](z: B)(op: (B, A) => B): LazyListIterable[B]^{this, op} = + if (knownIsEmpty) newLL(sCons(z, LazyListIterable.empty)) else newLL(scanLeftState(z)(op)) private def scanLeftState[B](z: B)(op: (B, A) => B): State[B]^{this, op} = @@ -423,18 +429,18 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta } ) - /** LazyList specialization of reduceLeft which allows GC to collect + /** LazyListIterable specialization of reduceLeft which allows GC to collect * along the way. * * @tparam B The type of value being accumulated. - * @param f The operation to perform on successive elements of the `LazyList`. + * @param f The operation to perform on successive elements of the `LazyListIterable`. * @return The accumulated value from successive applications of `f`. */ override def reduceLeft[B >: A](f: (B, A) => B): B = { if (this.isEmpty) throw new UnsupportedOperationException("empty.reduceLeft") else { var reducedRes: B = this.head - var left: LazyList[A]^{this} = this.tail + var left: LazyListIterable[A]^{this} = this.tail while (!left.isEmpty) { reducedRes = f(reducedRes, left.head) left = left.tail @@ -447,13 +453,13 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def partition(p: A => Boolean): (LazyList[A]^{this, p}, LazyList[A]^{this, p}) = (filter(p), filterNot(p)) + override def partition(p: A => Boolean): (LazyListIterable[A]^{this, p}, LazyListIterable[A]^{this, p}) = (filter(p), filterNot(p)) /** @inheritdoc * * $preservesLaziness */ - override def partitionMap[A1, A2](f: A => Either[A1, A2]): (LazyList[A1]^{this, f}, LazyList[A2]^{this, f}) = { + override def partitionMap[A1, A2](f: A => Either[A1, A2]): (LazyListIterable[A1]^{this, f}, LazyListIterable[A2]^{this, f}) = { val (left, right) = map(f).partition(_.isLeft) (left.map(_.asInstanceOf[Left[A1, _]].value), right.map(_.asInstanceOf[Right[_, A2]].value)) } @@ -462,17 +468,17 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def filter(pred: A => Boolean): LazyList[A]^{this, pred} = - if (knownIsEmpty) LazyList.empty - else LazyList.filterImpl(this, pred, isFlipped = false) + override def filter(pred: A => Boolean): LazyListIterable[A]^{this, pred} = + if (knownIsEmpty) LazyListIterable.empty + else LazyListIterable.filterImpl(this, pred, isFlipped = false) /** @inheritdoc * * $preservesLaziness */ - override def filterNot(pred: A => Boolean): LazyList[A]^{this, pred} = - if (knownIsEmpty) LazyList.empty - else LazyList.filterImpl(this, pred, isFlipped = true) + override def filterNot(pred: A => Boolean): LazyListIterable[A]^{this, pred} = + if (knownIsEmpty) LazyListIterable.empty + else LazyListIterable.filterImpl(this, pred, isFlipped = true) /** A `collection.WithFilter` which allows GC of the head of lazy list during processing. * @@ -482,21 +488,21 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * The `collection.WithFilter` returned by this method preserves laziness; elements are * only evaluated individually as needed. */ - override def withFilter(p: A => Boolean): collection.WithFilter[A, LazyList]^{this, p} = - new LazyList.WithFilter(coll, p) + override def withFilter(p: A => Boolean): collection.WithFilter[A, LazyListIterable]^{this, p} = + new LazyListIterable.WithFilter(coll, p) /** @inheritdoc * * $preservesLaziness */ - def prepended[B >: A](elem: B): LazyList[B] = newLL(sCons(elem, this)) + def prepended[B >: A](elem: B): LazyListIterable[B] = newLL(sCons(elem, this)) /** @inheritdoc * * $preservesLaziness */ - def prependedAll[B >: A](prefix: collection.IterableOnce[B]^): LazyList[B]^{this, prefix} = - if (knownIsEmpty) LazyList.from(prefix) + def prependedAll[B >: A](prefix: collection.IterableOnce[B]^): LazyListIterable[B]^{this, prefix} = + if (knownIsEmpty) LazyListIterable.from(prefix) else if (prefix.knownSize == 0) this else newLL(stateFromIteratorConcatSuffix(prefix.iterator)(state)) @@ -504,17 +510,17 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def map[B](f: A => B): LazyList[B]^{this, f} = - if (knownIsEmpty) LazyList.empty + override def map[B](f: A => B): LazyListIterable[B]^{this, f} = + if (knownIsEmpty) LazyListIterable.empty else (mapImpl(f): @inline) /** @inheritdoc * * $preservesLaziness */ - override def tapEach[U](f: A => U): LazyList[A]^{this, f} = map { a => f(a); a } + override def tapEach[U](f: A => U): LazyListIterable[A]^{this, f} = map { a => f(a); a } - private def mapImpl[B](f: A => B): LazyList[B]^{this, f} = + private def mapImpl[B](f: A => B): LazyListIterable[B]^{this, f} = newLL { if (isEmpty) State.Empty else sCons(f(head), tail.mapImpl(f)) @@ -524,9 +530,9 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def collect[B](pf: PartialFunction[A, B]^): LazyList[B]^{this, pf} = - if (knownIsEmpty) LazyList.empty - else LazyList.collectImpl(this, pf) + override def collect[B](pf: PartialFunction[A, B]^): LazyListIterable[B]^{this, pf} = + if (knownIsEmpty) LazyListIterable.empty + else LazyListIterable.collectImpl(this, pf) /** @inheritdoc * @@ -537,7 +543,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta override def collectFirst[B](pf: PartialFunction[A, B]): Option[B] = if (isEmpty) None else { - val res = pf.applyOrElse(head, LazyList.anyToMarker.asInstanceOf[A => B]) + val res = pf.applyOrElse(head, LazyListIterable.anyToMarker.asInstanceOf[A => B]) if (res.asInstanceOf[AnyRef] eq Statics.pfMarker) tail.collectFirst(pf) else Some(res) } @@ -562,22 +568,22 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta */ // optimisations are not for speed, but for functionality // see tickets #153, #498, #2147, and corresponding tests in run/ (as well as run/stream_flatmap_odds.scala) - override def flatMap[B](f: A => IterableOnce[B]^): LazyList[B]^{this, f} = - if (knownIsEmpty) LazyList.empty - else LazyList.flatMapImpl(this, f) + override def flatMap[B](f: A => IterableOnce[B]^): LazyListIterable[B]^{this, f} = + if (knownIsEmpty) LazyListIterable.empty + else LazyListIterable.flatMapImpl(this, f) /** @inheritdoc * * $preservesLaziness */ - override def flatten[B](implicit asIterable: A -> IterableOnce[B]): LazyList[B]^{this} = flatMap(asIterable) + override def flatten[B](implicit asIterable: A -> IterableOnce[B]): LazyListIterable[B]^{this} = flatMap(asIterable) /** @inheritdoc * * $preservesLaziness */ - override def zip[B](that: collection.IterableOnce[B]^): LazyList[(A, B)]^{this, that} = - if (this.knownIsEmpty || that.knownSize == 0) LazyList.empty + override def zip[B](that: collection.IterableOnce[B]^): LazyListIterable[(A, B)]^{this, that} = + if (this.knownIsEmpty || that.knownSize == 0) LazyListIterable.empty else newLL(zipState(that.iterator)) private def zipState[B](it: Iterator[B]^): State[(A, B)]^{this, it} = @@ -588,29 +594,29 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def zipWithIndex: LazyList[(A, Int)]^{this} = this zip LazyList.from(0) + override def zipWithIndex: LazyListIterable[(A, Int)]^{this} = this zip LazyListIterable.from(0) /** @inheritdoc * * $preservesLaziness */ - override def zipAll[A1 >: A, B](that: collection.Iterable[B]^, thisElem: A1, thatElem: B): LazyList[(A1, B)]^{this, that} = { + override def zipAll[A1 >: A, B](that: collection.Iterable[B]^, thisElem: A1, thatElem: B): LazyListIterable[(A1, B)]^{this, that} = { if (this.knownIsEmpty) { - if (that.knownSize == 0) LazyList.empty - else LazyList.continually(thisElem) zip that + if (that.knownSize == 0) LazyListIterable.empty + else LazyListIterable.continually(thisElem) zip that } else { - if (that.knownSize == 0) zip(LazyList.continually(thatElem)) + if (that.knownSize == 0) zip(LazyListIterable.continually(thatElem)) else newLL(zipAllState(that.iterator, thisElem, thatElem)) } } private def zipAllState[A1 >: A, B](it: Iterator[B]^, thisElem: A1, thatElem: B): State[(A1, B)]^{this, it} = { if (it.hasNext) { - if (this.isEmpty) sCons((thisElem, it.next()), newLL { LazyList.continually(thisElem) zipState it }) + if (this.isEmpty) sCons((thisElem, it.next()), newLL { LazyListIterable.continually(thisElem) zipState it }) else sCons((this.head, it.next()), newLL { this.tail.zipAllState(it, thisElem, thatElem) }) } else { if (this.isEmpty) State.Empty - else sCons((this.head, thatElem), this.tail zip LazyList.continually(thatElem)) + else sCons((this.head, thatElem), this.tail zip LazyListIterable.continually(thatElem)) } } @@ -623,21 +629,21 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * only evaluated individually as needed. */ // just in case it can be meaningfully overridden at some point - override def lazyZip[B](that: collection.Iterable[B]^): LazyZip2[A, B, LazyList.this.type]^{this, that} = + override def lazyZip[B](that: collection.Iterable[B]^): LazyZip2[A, B, LazyListIterable.this.type]^{this, that} = super.lazyZip(that) /** @inheritdoc * * $preservesLaziness */ - override def unzip[A1, A2](implicit asPair: A -> (A1, A2)): (LazyList[A1]^{this}, LazyList[A2]^{this}) = + override def unzip[A1, A2](implicit asPair: A -> (A1, A2)): (LazyListIterable[A1]^{this}, LazyListIterable[A2]^{this}) = (map(asPair(_)._1), map(asPair(_)._2)) /** @inheritdoc * * $preservesLaziness */ - override def unzip3[A1, A2, A3](implicit asTriple: A -> (A1, A2, A3)): (LazyList[A1]^{this}, LazyList[A2]^{this}, LazyList[A3]^{this}) = + override def unzip3[A1, A2, A3](implicit asTriple: A -> (A1, A2, A3)): (LazyListIterable[A1]^{this}, LazyListIterable[A2]^{this}, LazyListIterable[A3]^{this}) = (map(asTriple(_)._1), map(asTriple(_)._2), map(asTriple(_)._3)) /** @inheritdoc @@ -645,27 +651,27 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * $initiallyLazy * Additionally, it preserves laziness for all except the first `n` elements. */ - override def drop(n: Int): LazyList[A]^{this} = + override def drop(n: Int): LazyListIterable[A]^{this} = if (n <= 0) this - else if (knownIsEmpty) LazyList.empty - else LazyList.dropImpl(this, n) + else if (knownIsEmpty) LazyListIterable.empty + else LazyListIterable.dropImpl(this, n) /** @inheritdoc * * $initiallyLazy * Additionally, it preserves laziness for all elements after the predicate returns `false`. */ - override def dropWhile(p: A => Boolean): LazyList[A]^{this, p} = - if (knownIsEmpty) LazyList.empty - else LazyList.dropWhileImpl(this, p) + override def dropWhile(p: A => Boolean): LazyListIterable[A]^{this, p} = + if (knownIsEmpty) LazyListIterable.empty + else LazyListIterable.dropWhileImpl(this, p) /** @inheritdoc * * $initiallyLazy */ - override def dropRight(n: Int): LazyList[A]^{this} = { + override def dropRight(n: Int): LazyListIterable[A]^{this} = { if (n <= 0) this - else if (knownIsEmpty) LazyList.empty + else if (knownIsEmpty) LazyListIterable.empty else newLL { var scout = this var remaining = n @@ -678,7 +684,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta } } - private def dropRightState(scout: LazyList[_]^): State[A]^{this, scout} = + private def dropRightState(scout: LazyListIterable[_]^): State[A]^{this, scout} = if (scout.isEmpty) State.Empty else sCons(head, newLL(tail.dropRightState(scout.tail))) @@ -686,12 +692,12 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def take(n: Int): LazyList[A] = - if (knownIsEmpty) LazyList.empty + override def take(n: Int): LazyListIterable[A] = + if (knownIsEmpty) LazyListIterable.empty else (takeImpl(n): @inline) - private def takeImpl(n: Int): LazyList[A] = { - if (n <= 0) LazyList.empty + private def takeImpl(n: Int): LazyListIterable[A] = { + if (n <= 0) LazyListIterable.empty else newLL { if (isEmpty) State.Empty else sCons(head, tail.takeImpl(n - 1)) @@ -702,11 +708,11 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - override def takeWhile(p: A => Boolean): LazyList[A]^{this, p} = - if (knownIsEmpty) LazyList.empty + override def takeWhile(p: A => Boolean): LazyListIterable[A]^{this, p} = + if (knownIsEmpty) LazyListIterable.empty else (takeWhileImpl(p): @inline) - private def takeWhileImpl(p: A => Boolean): LazyList[A]^{this, p} = + private def takeWhileImpl(p: A => Boolean): LazyListIterable[A]^{this, p} = newLL { if (isEmpty || !p(head)) State.Empty else sCons(head, tail.takeWhileImpl(p)) @@ -716,26 +722,26 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $initiallyLazy */ - override def takeRight(n: Int): LazyList[A]^{this} = - if (n <= 0 || knownIsEmpty) LazyList.empty - else LazyList.takeRightImpl(this, n) + override def takeRight(n: Int): LazyListIterable[A]^{this} = + if (n <= 0 || knownIsEmpty) LazyListIterable.empty + else LazyListIterable.takeRightImpl(this, n) /** @inheritdoc * * $initiallyLazy * Additionally, it preserves laziness for all but the first `from` elements. */ - override def slice(from: Int, until: Int): LazyList[A]^{this} = take(until).drop(from) + override def slice(from: Int, until: Int): LazyListIterable[A]^{this} = take(until).drop(from) /** @inheritdoc * * $evaluatesAllElements */ - def reverse: LazyList[A] = reverseOnto(LazyList.empty) + def reverse: LazyListIterable[A] = reverseOnto(LazyListIterable.empty) - // need contravariant type B to make the compiler happy - still returns LazyList[A] + // need contravariant type B to make the compiler happy - still returns LazyListIterable[A] @tailrec - private def reverseOnto[B >: A](tl: LazyList[B]): LazyList[B] = + private def reverseOnto[B >: A](tl: LazyListIterable[B]): LazyListIterable[B] = if (isEmpty) tl else tail.reverseOnto(newLL(sCons(head, tl))) @@ -750,7 +756,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * The iterator returned by this method mostly preserves laziness; * a single element ahead of the iterator is evaluated. */ - override def grouped(size: Int): Iterator[LazyList[A]] = { + override def grouped(size: Int): Iterator[LazyListIterable[A]] = { require(size > 0, "size must be positive, but was " + size) slidingImpl(size = size, step = size) } @@ -760,12 +766,12 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * The iterator returned by this method mostly preserves laziness; * `size - step max 1` elements ahead of the iterator are evaluated. */ - override def sliding(size: Int, step: Int): Iterator[LazyList[A]] = { + override def sliding(size: Int, step: Int): Iterator[LazyListIterable[A]] = { require(size > 0 && step > 0, s"size=$size and step=$step, but both must be positive") slidingImpl(size = size, step = step) } - @inline private def slidingImpl(size: Int, step: Int): Iterator[LazyList[A]] = + @inline private def slidingImpl(size: Int, step: Int): Iterator[LazyListIterable[A]] = if (knownIsEmpty) Iterator.empty else new SlidingIterator[A](this, size = size, step = step) @@ -773,10 +779,10 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - def padTo[B >: A](len: Int, elem: B): LazyList[B]^{this} = { + def padTo[B >: A](len: Int, elem: B): LazyListIterable[B]^{this} = { if (len <= 0) this else newLL { - if (isEmpty) LazyList.fill(len)(elem).state + if (isEmpty) LazyListIterable.fill(len)(elem).state else sCons(head, tail.padTo(len - 1, elem)) } } @@ -785,13 +791,13 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * $preservesLaziness */ - def patch[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): LazyList[B]^{this, other} = - if (knownIsEmpty) LazyList from other + def patch[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): LazyListIterable[B]^{this, other} = + if (knownIsEmpty) LazyListIterable from other else patchImpl(from, other, replaced) - private def patchImpl[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): LazyList[B]^{this, other} = + private def patchImpl[B >: A](from: Int, other: IterableOnce[B]^, replaced: Int): LazyListIterable[B]^{this, other} = newLL { - if (from <= 0) stateFromIteratorConcatSuffix(other.iterator)(LazyList.dropImpl(this, replaced).state) + if (from <= 0) stateFromIteratorConcatSuffix(other.iterator)(LazyListIterable.dropImpl(this, replaced).state) else if (isEmpty) stateFromIterator(other.iterator) else sCons(head, tail.patchImpl(from - 1, other, replaced)) } @@ -801,17 +807,17 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * $evaluatesAllElements */ // overridden just in case a lazy implementation is developed at some point - override def transpose[B](implicit asIterable: A -> collection.Iterable[B]): LazyList[LazyList[B]]^{this} = super.transpose + override def transpose[B](implicit asIterable: A -> collection.Iterable[B]): LazyListIterable[LazyListIterable[B]]^{this} = super.transpose /** @inheritdoc * * $preservesLaziness */ - def updated[B >: A](index: Int, elem: B): LazyList[B]^{this} = + def updated[B >: A](index: Int, elem: B): LazyListIterable[B]^{this} = if (index < 0) throw new IndexOutOfBoundsException(s"$index") else updatedImpl(index, elem, index) - private def updatedImpl[B >: A](index: Int, elem: B, startIndex: Int): LazyList[B]^{this} = { + private def updatedImpl[B >: A](index: Int, elem: B, startIndex: Int): LazyListIterable[B]^{this} = { newLL { if (index <= 0) sCons(elem, tail) else if (tail.isEmpty) throw new IndexOutOfBoundsException(startIndex.toString) @@ -870,7 +876,7 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta // if cursor (eq scout) has state defined, it is empty; else unknown state if (!cursor.stateDefined) b.append(sep).append("") } else { - @inline def same(a: LazyList[A]^, b: LazyList[A]^): Boolean = (a eq b) || (a.state eq b.state) + @inline def same(a: LazyListIterable[A]^, b: LazyListIterable[A]^): Boolean = (a eq b) || (a.state eq b.state) // Cycle. // If we have a prefix of length P followed by a cycle of length C, // the scout will be at position (P%C) in the cycle when the cursor @@ -913,9 +919,9 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta * * Examples: * - * - `"LazyList(4, <not computed>)"`, a non-empty lazy list ; - * - `"LazyList(1, 2, 3, <not computed>)"`, a lazy list with at least three elements ; - * - `"LazyList(1, 2, 3, <cycle>)"`, an infinite lazy list that contains + * - `"LazyListIterable(4, <not computed>)"`, a non-empty lazy list ; + * - `"LazyListIterable(1, 2, 3, <not computed>)"`, a lazy list with at least three elements ; + * - `"LazyListIterable(1, 2, 3, <cycle>)"`, an infinite lazy list that contains * a cycle at the fourth element. */ override def toString(): String = addStringNoForce(new JStringBuilder(className), "(", ", ", ")").toString @@ -950,47 +956,47 @@ final class LazyList[+A] private(private[this] var lazyState: () => LazyList.Sta /** * $factoryInfo * @define coll lazy list - * @define Coll `LazyList` + * @define Coll `LazyListIterable` */ @SerialVersionUID(3L) -object LazyList extends IterableFactory[LazyList] { +object LazyListIterable extends IterableFactory[LazyListIterable] { // Eagerly evaluate cached empty instance private[this] val _empty = newLL(State.Empty).force private sealed trait State[+A] extends Serializable { this: State[A]^ => def head: A - def tail: LazyList[A]^ + def tail: LazyListIterable[A]^ } private object State { @SerialVersionUID(3L) object Empty extends State[Nothing] { def head: Nothing = throw new NoSuchElementException("head of empty lazy list") - def tail: LazyList[Nothing] = throw new UnsupportedOperationException("tail of empty lazy list") + def tail: LazyListIterable[Nothing] = throw new UnsupportedOperationException("tail of empty lazy list") } @SerialVersionUID(3L) - final class Cons[A](val head: A, val tail: LazyList[A]^) extends State[A] + final class Cons[A](val head: A, val tail: LazyListIterable[A]^) extends State[A] } - /** Creates a new LazyList. */ - @inline private def newLL[A](state: => State[A]^): LazyList[A]^{state} = new LazyList[A](() => state) + /** Creates a new LazyListIterable. */ + @inline private def newLL[A](state: => State[A]^): LazyListIterable[A]^{state} = new LazyListIterable[A](() => state) /** Creates a new State.Cons. */ - @inline private def sCons[A](hd: A, tl: LazyList[A]^): State[A]^{tl} = new State.Cons[A](hd, tl) + @inline private def sCons[A](hd: A, tl: LazyListIterable[A]^): State[A]^{tl} = new State.Cons[A](hd, tl) private val anyToMarker: Any => Any = _ => Statics.pfMarker /* All of the following `Impl` methods are carefully written so as not to - * leak the beginning of the `LazyList`. They copy the initial `LazyList` (`ll`) into + * leak the beginning of the `LazyListIterable`. They copy the initial `LazyListIterable` (`ll`) into * `var rest`, which gets closed over as a `scala.runtime.ObjectRef`, thus not permanently - * leaking the head of the `LazyList`. Additionally, the methods are written so that, should - * an exception be thrown by the evaluation of the `LazyList` or any supplied function, they + * leaking the head of the `LazyListIterable`. Additionally, the methods are written so that, should + * an exception be thrown by the evaluation of the `LazyListIterable` or any supplied function, they * can continue their execution where they left off. */ - private def filterImpl[A](ll: LazyList[A]^, p: A => Boolean, isFlipped: Boolean): LazyList[A]^{ll, p} = { + private def filterImpl[A](ll: LazyListIterable[A]^, p: A => Boolean, isFlipped: Boolean): LazyListIterable[A]^{ll, p} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1007,7 +1013,7 @@ object LazyList extends IterableFactory[LazyList] { } } - private def collectImpl[A, B](ll: LazyList[A]^, pf: PartialFunction[A, B]^): LazyList[B]^{ll, pf} = { + private def collectImpl[A, B](ll: LazyListIterable[A]^, pf: PartialFunction[A, B]^): LazyListIterable[B]^{ll, pf} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1026,7 +1032,7 @@ object LazyList extends IterableFactory[LazyList] { } } - private def flatMapImpl[A, B](ll: LazyList[A]^, f: A => IterableOnce[B]^): LazyList[B]^{ll, f} = { + private def flatMapImpl[A, B](ll: LazyListIterable[A]^, f: A => IterableOnce[B]^): LazyListIterable[B]^{ll, f} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1050,7 +1056,7 @@ object LazyList extends IterableFactory[LazyList] { } } - private def dropImpl[A](ll: LazyList[A]^, n: Int): LazyList[A]^{ll} = { + private def dropImpl[A](ll: LazyListIterable[A]^, n: Int): LazyListIterable[A]^{ll} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) var iRef = n // val iRef = new IntRef(n) @@ -1067,7 +1073,7 @@ object LazyList extends IterableFactory[LazyList] { } } - private def dropWhileImpl[A](ll: LazyList[A]^, p: A => Boolean): LazyList[A]^{ll, p} = { + private def dropWhileImpl[A](ll: LazyListIterable[A]^, p: A => Boolean): LazyListIterable[A]^{ll, p} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) newLL { @@ -1080,7 +1086,7 @@ object LazyList extends IterableFactory[LazyList] { } } - private def takeRightImpl[A](ll: LazyList[A]^, n: Int): LazyList[A]^{ll} = { + private def takeRightImpl[A](ll: LazyListIterable[A]^, n: Int): LazyListIterable[A]^{ll} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD var restRef = ll // val restRef = new ObjectRef(ll) var scoutRef = ll // val scoutRef = new ObjectRef(ll) @@ -1108,42 +1114,42 @@ object LazyList extends IterableFactory[LazyList] { } } - /** An alternative way of building and matching lazy lists using LazyList.cons(hd, tl). + /** An alternative way of building and matching lazy lists using LazyListIterable.cons(hd, tl). */ object cons { /** A lazy list consisting of a given first element and remaining elements * @param hd The first element of the result lazy list * @param tl The remaining elements of the result lazy list */ - def apply[A](hd: => A, tl: => LazyList[A]^): LazyList[A]^{hd, tl} = newLL(sCons(hd, newLL(tl.state))) + def apply[A](hd: => A, tl: => LazyListIterable[A]^): LazyListIterable[A]^{hd, tl} = newLL(sCons(hd, newLL(tl.state))) /** Maps a lazy list to its head and tail */ - def unapply[A](xs: LazyList[A]^): Option[(A, LazyList[A]^{xs})] = #::.unapply(xs) + def unapply[A](xs: LazyListIterable[A]^): Option[(A, LazyListIterable[A]^{xs})] = #::.unapply(xs) } - extension [A](l: => LazyList[A]) - /** Construct a LazyList consisting of a given first element followed by elements - * from another LazyList. + extension [A](l: => LazyListIterable[A]) + /** Construct a LazyListIterable consisting of a given first element followed by elements + * from another LazyListIterable. */ - def #:: [B >: A](elem: => B): LazyList[B]^{elem, l} = newLL(sCons(elem, newLL(l.state))) + def #:: [B >: A](elem: => B): LazyListIterable[B]^{elem, l} = newLL(sCons(elem, newLL(l.state))) - /** Construct a LazyList consisting of the concatenation of the given LazyList and - * another LazyList. + /** Construct a LazyListIterable consisting of the concatenation of the given LazyListIterable and + * another LazyListIterable. */ - def #:::[B >: A](prefix: LazyList[B]^): LazyList[B]^{prefix, l} = prefix lazyAppendedAll l + def #:::[B >: A](prefix: LazyListIterable[B]^): LazyListIterable[B]^{prefix, l} = prefix lazyAppendedAll l object #:: { - def unapply[A](s: LazyList[A]^): Option[(A, LazyList[A]^{s})] = + def unapply[A](s: LazyListIterable[A]^): Option[(A, LazyListIterable[A]^{s})] = if (!s.isEmpty) Some((s.head, s.tail)) else None } - def from[A](coll: collection.IterableOnce[A]^): LazyList[A]^{coll} = coll match { - case lazyList: LazyList[A] => lazyList + def from[A](coll: collection.IterableOnce[A]^): LazyListIterable[A]^{coll} = coll match { + case lazyList: LazyListIterable[A] => lazyList case _ if coll.knownSize == 0 => empty[A] case _ => newLL(stateFromIterator(coll.iterator)) } - def empty[A]: LazyList[A] = _empty + def empty[A]: LazyListIterable[A] = _empty /** Creates a State from an Iterator, with another State appended after the Iterator * is empty. @@ -1157,7 +1163,7 @@ object LazyList extends IterableFactory[LazyList] { if (it.hasNext) sCons(it.next(), newLL(stateFromIterator(it))) else State.Empty - override def concat[A](xss: collection.Iterable[A]*): LazyList[A] = + override def concat[A](xss: collection.Iterable[A]*): LazyListIterable[A] = if (xss.knownSize == 0) empty else newLL(concatIterator(xss.iterator)) @@ -1165,58 +1171,58 @@ object LazyList extends IterableFactory[LazyList] { if (!it.hasNext) State.Empty else stateFromIteratorConcatSuffix(it.next().iterator)(concatIterator(it)) - /** An infinite LazyList that repeatedly applies a given function to a start value. + /** An infinite LazyListIterable that repeatedly applies a given function to a start value. * - * @param start the start value of the LazyList + * @param start the start value of the LazyListIterable * @param f the function that's repeatedly applied - * @return the LazyList returning the infinite sequence of values `start, f(start), f(f(start)), ...` + * @return the LazyListIterable returning the infinite sequence of values `start, f(start), f(f(start)), ...` */ - def iterate[A](start: => A)(f: A => A): LazyList[A]^{start, f} = + def iterate[A](start: => A)(f: A => A): LazyListIterable[A]^{start, f} = newLL { val head = start sCons(head, iterate(f(head))(f)) } /** - * Create an infinite LazyList starting at `start` and incrementing by + * Create an infinite LazyListIterable starting at `start` and incrementing by * step `step`. * - * @param start the start value of the LazyList - * @param step the increment value of the LazyList - * @return the LazyList starting at value `start`. + * @param start the start value of the LazyListIterable + * @param step the increment value of the LazyListIterable + * @return the LazyListIterable starting at value `start`. */ - def from(start: Int, step: Int): LazyList[Int] = + def from(start: Int, step: Int): LazyListIterable[Int] = newLL(sCons(start, from(start + step, step))) /** - * Create an infinite LazyList starting at `start` and incrementing by `1`. + * Create an infinite LazyListIterable starting at `start` and incrementing by `1`. * - * @param start the start value of the LazyList - * @return the LazyList starting at value `start`. + * @param start the start value of the LazyListIterable + * @return the LazyListIterable starting at value `start`. */ - def from(start: Int): LazyList[Int] = from(start, 1) + def from(start: Int): LazyListIterable[Int] = from(start, 1) /** - * Create an infinite LazyList containing the given element expression (which + * Create an infinite LazyListIterable containing the given element expression (which * is computed for each occurrence). * - * @param elem the element composing the resulting LazyList - * @return the LazyList containing an infinite number of elem + * @param elem the element composing the resulting LazyListIterable + * @return the LazyListIterable containing an infinite number of elem */ - def continually[A](elem: => A): LazyList[A]^{elem} = newLL(sCons(elem, continually(elem))) + def continually[A](elem: => A): LazyListIterable[A]^{elem} = newLL(sCons(elem, continually(elem))) - override def fill[A](n: Int)(elem: => A): LazyList[A]^{elem} = + override def fill[A](n: Int)(elem: => A): LazyListIterable[A]^{elem} = if (n > 0) newLL(sCons(elem, fill(n - 1)(elem))) else empty - override def tabulate[A](n: Int)(f: Int => A): LazyList[A]^{f} = { - def at(index: Int): LazyList[A]^{f} = + override def tabulate[A](n: Int)(f: Int => A): LazyListIterable[A]^{f} = { + def at(index: Int): LazyListIterable[A]^{f} = if (index < n) newLL(sCons(f(index), at(index + 1))) else empty at(0) } // significantly simpler than the iterator returned by Iterator.unfold - override def unfold[A, S](init: S)(f: S => Option[(A, S)]): LazyList[A]^{f} = + override def unfold[A, S](init: S)(f: S => Option[(A, S)]): LazyListIterable[A]^{f} = newLL { f(init) match { case Some((elem, state)) => sCons(elem, unfold(state)(f)) @@ -1230,9 +1236,9 @@ object LazyList extends IterableFactory[LazyList] { * @tparam A the type of the ${coll}’s elements * @return A builder for $Coll objects. */ - def newBuilder[A]: Builder[A, LazyList[A]] = new LazyBuilder[A] + def newBuilder[A]: Builder[A, LazyListIterable[A]] = new LazyBuilder[A] - private class LazyIterator[+A](private[this] var lazyList: LazyList[A]^) extends AbstractIterator[A] { + private class LazyIterator[+A](private[this] var lazyList: LazyListIterable[A]^) extends AbstractIterator[A] { override def hasNext: Boolean = !lazyList.isEmpty override def next(): A = @@ -1244,8 +1250,8 @@ object LazyList extends IterableFactory[LazyList] { } } - private class SlidingIterator[A](private[this] var lazyList: LazyList[A]^, size: Int, step: Int) - extends AbstractIterator[LazyList[A]] { + private class SlidingIterator[A](private[this] var lazyList: LazyListIterable[A]^, size: Int, step: Int) + extends AbstractIterator[LazyListIterable[A]] { this: SlidingIterator[A]^ => private val minLen = size - step max 0 private var first = true @@ -1254,7 +1260,7 @@ object LazyList extends IterableFactory[LazyList] { if (first) !lazyList.isEmpty else lazyList.lengthGt(minLen) - def next(): LazyList[A] = { + def next(): LazyListIterable[A] = { if (!hasNext) Iterator.empty.next() else { first = false @@ -1265,21 +1271,21 @@ object LazyList extends IterableFactory[LazyList] { } } - private final class WithFilter[A] private[LazyList](lazyList: LazyList[A]^, p: A => Boolean) - extends collection.WithFilter[A, LazyList] { + private final class WithFilter[A] private[LazyListIterable](lazyList: LazyListIterable[A]^, p: A => Boolean) + extends collection.WithFilter[A, LazyListIterable] { this: WithFilter[A]^ => private[this] val filtered = lazyList.filter(p) - def map[B](f: A => B): LazyList[B]^{this, f} = filtered.map(f) - def flatMap[B](f: A => IterableOnce[B]^): LazyList[B]^{this, f} = filtered.flatMap(f) + def map[B](f: A => B): LazyListIterable[B]^{this, f} = filtered.map(f) + def flatMap[B](f: A => IterableOnce[B]^): LazyListIterable[B]^{this, f} = filtered.flatMap(f) def foreach[U](f: A => U): Unit = filtered.foreach(f) - def withFilter(q: A => Boolean): collection.WithFilter[A, LazyList]^{this, q} = new WithFilter(filtered, q) + def withFilter(q: A => Boolean): collection.WithFilter[A, LazyListIterable]^{this, q} = new WithFilter(filtered, q) } - private final class LazyBuilder[A] extends ReusableBuilder[A, LazyList[A]] { + private final class LazyBuilder[A] extends ReusableBuilder[A, LazyListIterable[A]] { import LazyBuilder._ private[this] var next: DeferredState[A @uncheckedCaptures] = _ - private[this] var list: LazyList[A @uncheckedCaptures] = _ + private[this] var list: LazyListIterable[A @uncheckedCaptures] = _ clear() @@ -1289,7 +1295,7 @@ object LazyList extends IterableFactory[LazyList] { next = deferred } - override def result(): LazyList[A] = { + override def result(): LazyListIterable[A] = { next init State.Empty list } @@ -1337,7 +1343,7 @@ object LazyList extends IterableFactory[LazyList] { * of long evaluated lazy lists without exhausting the stack through recursive serialization of cons cells. */ @SerialVersionUID(3L) - final class SerializationProxy[A](@transient protected var coll: LazyList[A]^) extends Serializable { + final class SerializationProxy[A](@transient protected var coll: LazyListIterable[A]^) extends Serializable { private[this] def writeObject(out: ObjectOutputStream): Unit = { out.defaultWriteObject() @@ -1358,9 +1364,9 @@ object LazyList extends IterableFactory[LazyList] { case SerializeEnd => initRead = true case a => init += a.asInstanceOf[A] } - val tail = in.readObject().asInstanceOf[LazyList[A]] + val tail = in.readObject().asInstanceOf[LazyListIterable[A]] // scala/scala#10118: caution that no code path can evaluate `tail.state` - // before the resulting LazyList is returned + // before the resulting LazyListIterable is returned val it = init.toList.iterator coll = newLL(stateFromIteratorConcatSuffix(it)(tail.state)) } From 9ae3ee71797d80f1261a1a548519ab4869953a3c Mon Sep 17 00:00:00 2001 From: odersky Date: Fri, 3 Nov 2023 10:44:50 +0100 Subject: [PATCH 82/89] Add generic/IsSeq to stdlib --- .../stdlib/collection/generic/IsSeq.scala | 117 ++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 tests/pos-special/stdlib/collection/generic/IsSeq.scala diff --git a/tests/pos-special/stdlib/collection/generic/IsSeq.scala b/tests/pos-special/stdlib/collection/generic/IsSeq.scala new file mode 100644 index 000000000000..84fcd7be14df --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/IsSeq.scala @@ -0,0 +1,117 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package generic + +import scala.reflect.ClassTag + +/** Type class witnessing that a collection representation type `Repr` has + * elements of type `A` and has a conversion to `SeqOps[A, Iterable, C]`, for + * some types `A` and `C`. + * + * This type enables simple enrichment of `Seq`s with extension methods which + * can make full use of the mechanics of the Scala collections framework in + * their implementation. + * + * @see [[scala.collection.generic.IsIterable]] + */ +trait IsSeq[Repr] extends IsIterable[Repr] { + + @deprecated("'conversion' is now a method named 'apply'", "2.13.0") + override val conversion: Repr => SeqOps[A, Iterable, C] = apply(_) + + /** A conversion from the type `Repr` to `SeqOps[A, Iterable, C]` + * + * @note The second type parameter of the returned `SeqOps` value is + * still `Iterable` (and not `Seq`) because `SeqView[A]` only + * extends `SeqOps[A, View, View[A]]`. + */ + def apply(coll: Repr): SeqOps[A, Iterable, C] +} + +object IsSeq { + + private val seqOpsIsSeqVal: IsSeq[Seq[Any]] = + new IsSeq[Seq[Any]] { + type A = Any + type C = Any + def apply(coll: Seq[Any]): SeqOps[Any, Iterable, Any] = coll + } + + implicit def seqOpsIsSeq[CC0[X] <: SeqOps[X, Iterable, CC0[X]], A0]: IsSeq[CC0[A0]] { type A = A0; type C = CC0[A0] } = + seqOpsIsSeqVal.asInstanceOf[IsSeq[CC0[A0]] { type A = A0; type C = CC0[A0] }] + +/* Under cc, views are not Seqs and can't use SeqOps. + + implicit def seqViewIsSeq[CC0[X] <: SeqView[X], A0]: IsSeq[CC0[A0]] { type A = A0; type C = View[A0] } = + new IsSeq[CC0[A0]] { + type A = A0 + type C = View[A] + def apply(coll: CC0[A0]): SeqOps[A0, View, View[A0]] = coll + } + + implicit val stringViewIsSeq: IsSeq[StringView] { type A = Char; type C = View[Char] } = + new IsSeq[StringView] { + type A = Char + type C = View[Char] + def apply(coll: StringView): SeqOps[Char, View, View[Char]] = coll + } + +*/ + implicit val stringIsSeq: IsSeq[String] { type A = Char; type C = String } = + new IsSeq[String] { + type A = Char + type C = String + def apply(s: String): SeqOps[Char, immutable.IndexedSeq, String] = + new SeqOps[Char, immutable.ArraySeq, String] { + def length: Int = s.length + def apply(i: Int): Char = s.charAt(i) + def toIterable: Iterable[Char] = new immutable.WrappedString(s) + protected[this] def coll: String = s + protected[this] def fromSpecific(coll: IterableOnce[Char]): String = coll.iterator.mkString + def iterableFactory: FreeSeqFactory[immutable.ArraySeq] = immutable.ArraySeq.untagged + override def empty: String = "" + protected[this] def newSpecificBuilder: mutable.Builder[Char, String] = new StringBuilder + def iterator: Iterator[Char] = s.iterator + } + } + + implicit def arrayIsSeq[A0 : ClassTag]: IsSeq[Array[A0]] { type A = A0; type C = Array[A0] } = + new IsSeq[Array[A0]] { + type A = A0 + type C = Array[A0] + def apply(a: Array[A0]): SeqOps[A0, Seq, Array[A0]] = + new SeqOps[A, mutable.ArraySeq, Array[A]] { + def apply(i: Int): A = a(i) + def length: Int = a.length + def toIterable: Iterable[A] = mutable.ArraySeq.make(a) + protected def coll: Array[A] = a + protected def fromSpecific(coll: IterableOnce[A]): Array[A] = Array.from(coll) + def iterableFactory: FreeSeqFactory[mutable.ArraySeq] = mutable.ArraySeq.untagged + override def empty: Array[A] = Array.empty[A] + protected def newSpecificBuilder: mutable.Builder[A, Array[A]] = Array.newBuilder + def iterator: Iterator[A] = a.iterator + } + } + + // `Range` can not be unified with the `CC0` parameter of the + // `seqOpsIsSeq` definition because it does not take a type parameter. + // Hence the need for a separate case: + implicit def rangeIsSeq[C0 <: Range]: IsSeq[C0] { type A = Int; type C = immutable.IndexedSeq[Int] } = + new IsSeq[C0] { + type A = Int + type C = immutable.IndexedSeq[Int] + def apply(coll: C0): SeqOps[Int, Seq, immutable.IndexedSeq[Int]] = coll + } + +} From f8f20508c1b225a55693262e7d3cac37b945d09c Mon Sep 17 00:00:00 2001 From: odersky Date: Fri, 3 Nov 2023 11:08:46 +0100 Subject: [PATCH 83/89] Make SubstRecThis typemap idempotent --- compiler/src/dotty/tools/dotc/core/Substituters.scala | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/compiler/src/dotty/tools/dotc/core/Substituters.scala b/compiler/src/dotty/tools/dotc/core/Substituters.scala index 5a641416b3e1..bd30177adcb4 100644 --- a/compiler/src/dotty/tools/dotc/core/Substituters.scala +++ b/compiler/src/dotty/tools/dotc/core/Substituters.scala @@ -189,7 +189,7 @@ object Substituters: def apply(tp: Type): Type = substThis(tp, from, to, this)(using mapCtx) } - final class SubstRecThisMap(from: Type, to: Type)(using Context) extends DeepTypeMap { + final class SubstRecThisMap(from: Type, to: Type)(using Context) extends DeepTypeMap, IdempotentCaptRefMap { def apply(tp: Type): Type = substRecThis(tp, from, to, this)(using mapCtx) } From b19f981675f537c9c7a4289abd5e731eeac26528 Mon Sep 17 00:00:00 2001 From: odersky Date: Fri, 3 Nov 2023 11:09:15 +0100 Subject: [PATCH 84/89] Capturecheck all files in generic --- .../collection/generic/BitOperations.scala | 51 ++++++ .../generic/DefaultSerializationProxy.scala | 90 ++++++++++ .../collection/generic/IsIterable.scala | 165 ++++++++++++++++++ .../collection/generic/IsIterableOnce.scala | 72 ++++++++ .../stdlib/collection/generic/IsMap.scala | 115 ++++++++++++ .../stdlib/collection/generic/IsSeq.scala | 32 ++-- .../collection/generic/Subtractable.scala | 63 +++++++ .../stdlib/collection/generic/package.scala | 35 ++++ 8 files changed, 610 insertions(+), 13 deletions(-) create mode 100644 tests/pos-special/stdlib/collection/generic/BitOperations.scala create mode 100644 tests/pos-special/stdlib/collection/generic/DefaultSerializationProxy.scala create mode 100644 tests/pos-special/stdlib/collection/generic/IsIterable.scala create mode 100644 tests/pos-special/stdlib/collection/generic/IsIterableOnce.scala create mode 100644 tests/pos-special/stdlib/collection/generic/IsMap.scala create mode 100644 tests/pos-special/stdlib/collection/generic/Subtractable.scala create mode 100644 tests/pos-special/stdlib/collection/generic/package.scala diff --git a/tests/pos-special/stdlib/collection/generic/BitOperations.scala b/tests/pos-special/stdlib/collection/generic/BitOperations.scala new file mode 100644 index 000000000000..f76619a004fa --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/BitOperations.scala @@ -0,0 +1,51 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package generic +import language.experimental.captureChecking + + +/** Some bit operations. + * + * See [[https://www.drmaciver.com/2008/08/unsigned-comparison-in-javascala/]] for + * an explanation of unsignedCompare. + */ +private[collection] object BitOperations { + trait Int { + type Int = scala.Int + def zero(i: Int, mask: Int) = (i & mask) == 0 + def mask(i: Int, mask: Int) = i & (complement(mask - 1) ^ mask) + def hasMatch(key: Int, prefix: Int, m: Int) = mask(key, m) == prefix + def unsignedCompare(i: Int, j: Int) = (i < j) ^ (i < 0) ^ (j < 0) + def shorter(m1: Int, m2: Int) = unsignedCompare(m2, m1) + def complement(i: Int) = (-1) ^ i + def bits(num: Int) = 31 to 0 by -1 map (i => (num >>> i & 1) != 0) + def bitString(num: Int, sep: String = "") = bits(num) map (b => if (b) "1" else "0") mkString sep + def highestOneBit(j: Int) = java.lang.Integer.highestOneBit(j) + } + object Int extends Int + + trait Long { + type Long = scala.Long + def zero(i: Long, mask: Long) = (i & mask) == 0L + def mask(i: Long, mask: Long) = i & (complement(mask - 1) ^ mask) + def hasMatch(key: Long, prefix: Long, m: Long) = mask(key, m) == prefix + def unsignedCompare(i: Long, j: Long) = (i < j) ^ (i < 0L) ^ (j < 0L) + def shorter(m1: Long, m2: Long) = unsignedCompare(m2, m1) + def complement(i: Long) = (-1L) ^ i + def bits(num: Long) = 63L to 0L by -1L map (i => (num >>> i & 1L) != 0L) + def bitString(num: Long, sep: String = "") = bits(num) map (b => if (b) "1" else "0") mkString sep + def highestOneBit(j: Long) = java.lang.Long.highestOneBit(j) + } + object Long extends Long +} diff --git a/tests/pos-special/stdlib/collection/generic/DefaultSerializationProxy.scala b/tests/pos-special/stdlib/collection/generic/DefaultSerializationProxy.scala new file mode 100644 index 000000000000..7eba9433b8d5 --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/DefaultSerializationProxy.scala @@ -0,0 +1,90 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection.generic + +import java.io.{ObjectInputStream, ObjectOutputStream} + +import scala.collection.{Factory, Iterable} +import scala.collection.mutable.Builder +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures + +/** The default serialization proxy for collection implementations. + * + * This class is `final` and requires an extra `Factory` object rather than leaving the details of creating a `Builder` + * to an abstract method that could be implemented by a subclass. This is necessary because the factory is needed + * for deserializing this class's private state, which happens before any subclass fields would be deserialized. Any + * additional state required to create the proper `Builder` needs to be captured by the `factory`. + */ +@SerialVersionUID(3L) +final class DefaultSerializationProxy[A](factory: Factory[A, Any], @transient private[this] val coll: Iterable[A]) extends Serializable { + + @transient protected var builder: Builder[A @uncheckedCaptures, Any] = _ + // @uncheckedCaptures OK since builder is used only locally when reading objects + + private[this] def writeObject(out: ObjectOutputStream): Unit = { + out.defaultWriteObject() + val k = coll.knownSize + out.writeInt(k) + var count = 0 + coll.foreach { x => + out.writeObject(x) + count += 1 + } + if(k >= 0) { + if(count != k) throw new IllegalStateException(s"Illegal size $count of collection, expected $k") + } else out.writeObject(SerializeEnd) + } + + private[this] def readObject(in: ObjectInputStream): Unit = { + in.defaultReadObject() + builder = factory.newBuilder + val k = in.readInt() + if(k >= 0) { + builder.sizeHint(k) + var count = 0 + while(count < k) { + builder += in.readObject().asInstanceOf[A] + count += 1 + } + } else { + while (true) in.readObject match { + case SerializeEnd => return + case a => builder += a.asInstanceOf[A] + } + } + } + + protected[this] def readResolve(): Any = builder.result() +} + +@SerialVersionUID(3L) +private[collection] case object SerializeEnd + +/** Mix-in trait to enable DefaultSerializationProxy for the standard collection types. Depending on the type + * it is mixed into, it will dynamically choose `iterableFactory`, `mapFactory`, `sortedIterableFactory` or + * `sortedMapFactory` for deserialization into the respective `CC` type. Override `writeReplace` or implement + * it directly without using this trait if you need a non-standard factory or if you want to use a different + * serialization scheme. + */ +trait DefaultSerializable extends Serializable { this: scala.collection.Iterable[_] => + protected[this] def writeReplace(): AnyRef = { + val f: Factory[Any, Any] = this match { + case it: scala.collection.SortedMap[_, _] => it.sortedMapFactory.sortedMapFactory[Any, Any](it.ordering.asInstanceOf[Ordering[Any]]).asInstanceOf[Factory[Any, Any]] + case it: scala.collection.Map[_, _] => it.mapFactory.mapFactory[Any, Any].asInstanceOf[Factory[Any, Any]] + case it: scala.collection.SortedSet[_] => it.sortedIterableFactory.evidenceIterableFactory[Any](it.ordering.asInstanceOf[Ordering[Any]]) + case it => it.iterableFactory.iterableFactory + } + new DefaultSerializationProxy(f, this) + } +} diff --git a/tests/pos-special/stdlib/collection/generic/IsIterable.scala b/tests/pos-special/stdlib/collection/generic/IsIterable.scala new file mode 100644 index 000000000000..c309299b615b --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/IsIterable.scala @@ -0,0 +1,165 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package generic +import language.experimental.captureChecking + +/** A trait which can be used to avoid code duplication when defining extension + * methods that should be applicable both to existing Scala collections (i.e., + * types extending `Iterable`) as well as other (potentially user-defined) + * types that could be converted to a Scala collection type. This trait + * makes it possible to treat Scala collections and types that can be implicitly + * converted to a collection type uniformly. For example, one can provide + * extension methods that work both on collection types and on `String`s (`String`s + * do not extend `Iterable`, but can be converted to `Iterable`) + * + * `IsIterable` provides three members: + * + * 1. type member `A`, which represents the element type of the target `Iterable[A]` + * 1. type member `C`, which represents the type returned by transformation operations that preserve the collection’s elements type + * 1. method `apply`, which provides a way to convert between the type we wish to add extension methods to, `Repr`, and `IterableOps[A, Iterable, C]`. + * + * ===Usage=== + * + * One must provide `IsIterable` as an implicit parameter type of an implicit + * conversion. Its usage is shown below. Our objective in the following example + * is to provide a generic extension method `mapReduce` to any type that extends + * or can be converted to `Iterable`. In our example, this includes + * `String`. + * + * {{{ + * import scala.collection.{Iterable, IterableOps} + * import scala.collection.generic.IsIterable + * + * class ExtensionMethods[Repr, I <: IsIterable[Repr]](coll: Repr, it: I) { + * def mapReduce[B](mapper: it.A => B)(reducer: (B, B) => B): B = { + * val iter = it(coll).iterator + * var res = mapper(iter.next()) + * while (iter.hasNext) + * res = reducer(res, mapper(iter.next())) + * res + * } + * } + * + * implicit def withExtensions[Repr](coll: Repr)(implicit it: IsIterable[Repr]): ExtensionMethods[Repr, it.type] = + * new ExtensionMethods(coll, it) + * + * // See it in action! + * List(1, 2, 3).mapReduce(_ * 2)(_ + _) // res0: Int = 12 + * "Yeah, well, you know, that's just, like, your opinion, man.".mapReduce(x => 1)(_ + _) // res1: Int = 59 + *}}} + * + * Here, we begin by creating a class `ExtensionMethods` which contains our + * `mapReduce` extension method. + * + * Note that `ExtensionMethods` takes a constructor argument `coll` of type `Repr`, where + * `Repr` represents (typically) the collection type, and an argument `it` of a subtype of `IsIterable[Repr]`. + * The body of the method starts by converting the `coll` argument to an `IterableOps` in order to + * call the `iterator` method on it. + * The remaining of the implementation is straightforward. + * + * The `withExtensions` implicit conversion makes the `mapReduce` operation available + * on any type `Repr` for which it exists an implicit `IsIterable[Repr]` instance. + * Note how we keep track of the precise type of the implicit `it` argument by using the + * `it.type` singleton type, rather than the wider `IsIterable[Repr]` type. We do that + * so that the information carried by the type members `A` and `C` of the `it` argument + * is not lost. + * + * When the `mapReduce` method is called on some type of which it is not + * a member, implicit search is triggered. Because implicit conversion + * `withExtensions` is generic, it will be applied as long as an implicit + * value of type `IsIterable[Repr]` can be found. Given that the + * `IsIterable` companion object contains implicit members that return values of type + * `IsIterable`, this requirement is typically satisfied, and the chain + * of interactions described in the previous paragraph is set into action. + * (See the `IsIterable` companion object, which contains a precise + * specification of the available implicits.) + * + * ''Note'': Currently, it's not possible to combine the implicit conversion and + * the class with the extension methods into an implicit class due to + * limitations of type inference. + * + * ===Implementing `IsIterable` for New Types=== + * + * One must simply provide an implicit value of type `IsIterable` + * specific to the new type, or an implicit conversion which returns an + * instance of `IsIterable` specific to the new type. + * + * Below is an example of an implementation of the `IsIterable` trait + * where the `Repr` type is `Range`. + * + *{{{ + * implicit val rangeRepr: IsIterable[Range] { type A = Int; type C = IndexedSeq[Int] } = + * new IsIterable[Range] { + * type A = Int + * type C = IndexedSeq[Int] + * def apply(coll: Range): IterableOps[Int, IndexedSeq, IndexedSeq[Int]] = coll + * } + *}}} + * + * (Note that in practice the `IsIterable[Range]` instance is already provided by + * the standard library, and it is defined as an `IsSeq[Range]` instance) + */ +trait IsIterable[Repr] extends IsIterableOnce[Repr] { + + /** The type returned by transformation operations that preserve the same elements + * type (e.g. `filter`, `take`). + * + * In practice, this type is often `Repr` itself, excepted in the case + * of `SeqView[A]` (and other `View[A]` subclasses), where it is “only” `View[A]`. + */ + type C + + @deprecated("'conversion' is now a method named 'apply'", "2.13.0") + override val conversion: Repr => IterableOps[A, Iterable, C] = apply(_) + + /** A conversion from the type `Repr` to `IterableOps[A, Iterable, C]` */ + def apply(coll: Repr): IterableOps[A, Iterable, C] + +} + +object IsIterable extends IsIterableLowPriority { + + // Straightforward case: IterableOps subclasses + implicit def iterableOpsIsIterable[A0, CC0[X] <: IterableOps[X, Iterable, CC0[X]]]: IsIterable[CC0[A0]] { type A = A0; type C = CC0[A0] } = + new IsIterable[CC0[A0]] { + type A = A0 + type C = CC0[A0] + def apply(coll: CC0[A]): IterableOps[A, Iterable, C] = coll + } + + // The `BitSet` type can not be unified with the `CC0` parameter of + // the above definition because it does not take a type parameter. + // Hence the need for a separate case: + implicit def bitSetOpsIsIterable[C0 <: BitSet with BitSetOps[C0]]: IsIterable[C0] { type A = Int; type C = C0 } = + new IsIterable[C0] { + type A = Int + type C = C0 + def apply(coll: C0): IterableOps[Int, Iterable, C0] = coll + } + +} + +trait IsIterableLowPriority { + + // Makes `IsSeq` instances visible in `IsIterable` companion + implicit def isSeqLikeIsIterable[Repr](implicit + isSeqLike: IsSeq[Repr] + ): IsIterable[Repr] { type A = isSeqLike.A; type C = isSeqLike.C } = isSeqLike + + // Makes `IsMap` instances visible in `IsIterable` companion + implicit def isMapLikeIsIterable[Repr](implicit + isMapLike: IsMap[Repr] + ): IsIterable[Repr] { type A = isMapLike.A; type C = isMapLike.C } = isMapLike + +} diff --git a/tests/pos-special/stdlib/collection/generic/IsIterableOnce.scala b/tests/pos-special/stdlib/collection/generic/IsIterableOnce.scala new file mode 100644 index 000000000000..2836ca2bb520 --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/IsIterableOnce.scala @@ -0,0 +1,72 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package generic +import language.experimental.captureChecking + +/** Type class witnessing that a collection representation type `Repr` has + * elements of type `A` and has a conversion to `IterableOnce[A]`. + * + * This type enables simple enrichment of `IterableOnce`s with extension + * methods which can make full use of the mechanics of the Scala collections + * framework in their implementation. + * + * Example usage, + * {{{ + * class FilterMapImpl[Repr, I <: IsIterableOnce[Repr]](coll: Repr, it: I) { + * final def filterMap[B, That](f: it.A => Option[B])(implicit bf: BuildFrom[Repr, B, That]): That = { + * val b = bf.newBuilder(coll) + * for(e <- it(coll).iterator) f(e) foreach (b +=) + * b.result() + * } + * } + * implicit def filterMap[Repr](coll: Repr)(implicit it: IsIterableOnce[Repr]): FilterMapImpl[Repr, it.type] = + * new FilterMapImpl(coll, it) + * + * List(1, 2, 3, 4, 5) filterMap (i => if(i % 2 == 0) Some(i) else None) + * // == List(2, 4) + * }}} + */ +trait IsIterableOnce[Repr] { + + /** The type of elements we can traverse over (e.g. `Int`). */ + type A + + @deprecated("'conversion' is now a method named 'apply'", "2.13.0") + val conversion: Repr => IterableOnce[A] = apply(_) + + /** A conversion from the representation type `Repr` to a `IterableOnce[A]`. */ + def apply(coll: Repr): IterableOnce[A] + +} + +object IsIterableOnce extends IsIterableOnceLowPriority { + + // Straightforward case: IterableOnce subclasses + implicit def iterableOnceIsIterableOnce[CC0[A] <: IterableOnce[A], A0]: IsIterableOnce[CC0[A0]] { type A = A0 } = + new IsIterableOnce[CC0[A0]] { + type A = A0 + def apply(coll: CC0[A0]): IterableOnce[A0] = coll + } + +} + +trait IsIterableOnceLowPriority { + + // Makes `IsIterable` instance visible in `IsIterableOnce` companion + implicit def isIterableLikeIsIterableOnce[Repr](implicit + isIterableLike: IsIterable[Repr] + ): IsIterableOnce[Repr] { type A = isIterableLike.A } = isIterableLike + +} diff --git a/tests/pos-special/stdlib/collection/generic/IsMap.scala b/tests/pos-special/stdlib/collection/generic/IsMap.scala new file mode 100644 index 000000000000..ad7254d2dd61 --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/IsMap.scala @@ -0,0 +1,115 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +package generic + +import IsMap.Tupled +import scala.collection.immutable.{IntMap, LongMap} +import language.experimental.captureChecking + +/** + * Type class witnessing that a collection type `Repr` + * has keys of type `K`, values of type `V` and has a conversion to + * `MapOps[K, V, Iterable, C]`, for some types `K`, `V` and `C`. + * + * This type enables simple enrichment of `Map`s with extension methods. + * + * @see [[scala.collection.generic.IsIterable]] + * @tparam Repr Collection type (e.g. `Map[Int, String]`) + */ +trait IsMap[Repr] extends IsIterable[Repr] { + + /** The type of keys */ + type K + + /** The type of values */ + type V + + type A = (K, V) + + /** A conversion from the type `Repr` to `MapOps[K, V, Iterable, C]` + * + * @note The third type parameter of the returned `MapOps` value is + * still `Iterable` (and not `Map`) because `MapView[K, V]` only + * extends `MapOps[K, V, View, View[A]]`. + */ + override def apply(c: Repr): MapOps[K, V, Tupled[Iterable]#Ap, C] + +} + +object IsMap { + + /** Convenient type level function that takes a unary type constructor `F[_]` + * and returns a binary type constructor that tuples its parameters and passes + * them to `F`. + * + * `Tupled[F]#Ap` is equivalent to `({ type Ap[X, +Y] = F[(X, Y)] })#Ap`. + */ + type Tupled[F[+_]] = { type Ap[X, Y] = F[(X, Y)] } + + // Map collections + implicit def mapOpsIsMap[CC0[X, Y] <: MapOps[X, Y, Tupled[Iterable]#Ap, CC0[X, Y]], K0, V0]: IsMap[CC0[K0, V0]] { type K = K0; type V = V0; type C = CC0[K, V] } = + new IsMap[CC0[K0, V0]] { + type K = K0 + type V = V0 + type C = CC0[K0, V0] + def apply(c: CC0[K0, V0]): MapOps[K0, V0, Tupled[Iterable]#Ap, C] = c + } + + // MapView + implicit def mapViewIsMap[CC0[X, Y] <: MapView[X, Y], K0, V0]: IsMap[CC0[K0, V0]] { type K = K0; type V = V0; type C = View[(K0, V0)] } = + new IsMap[CC0[K0, V0]] { + type K = K0 + type V = V0 + type C = View[(K, V)] + def apply(c: CC0[K0, V0]): MapOps[K0, V0, Tupled[Iterable]#Ap, View[(K0, V0)]] = c + } + + // AnyRefMap has stricter bounds than the ones used by the mapOpsIsMap definition + implicit def anyRefMapIsMap[K0 <: AnyRef, V0]: IsMap[mutable.AnyRefMap[K0, V0]] { type K = K0; type V = V0; type C = mutable.AnyRefMap[K0, V0] } = + new IsMap[mutable.AnyRefMap[K0, V0]] { + type K = K0 + type V = V0 + type C = mutable.AnyRefMap[K0, V0] + def apply(c: mutable.AnyRefMap[K0, V0]): MapOps[K0, V0, Tupled[Iterable]#Ap, mutable.AnyRefMap[K0, V0]] = c + } + + // IntMap takes one type parameter only whereas mapOpsIsMap uses a parameter CC0 with two type parameters + implicit def intMapIsMap[V0]: IsMap[IntMap[V0]] { type K = Int; type V = V0; type C = IntMap[V0] } = + new IsMap[IntMap[V0]] { + type K = Int + type V = V0 + type C = IntMap[V0] + def apply(c: IntMap[V0]): MapOps[Int, V0, Tupled[Iterable]#Ap, IntMap[V0]] = c + } + + // LongMap is in a similar situation as IntMap + implicit def longMapIsMap[V0]: IsMap[LongMap[V0]] { type K = Long; type V = V0; type C = LongMap[V0] } = + new IsMap[LongMap[V0]] { + type K = Long + type V = V0 + type C = LongMap[V0] + def apply(c: LongMap[V0]): MapOps[Long, V0, Tupled[Iterable]#Ap, LongMap[V0]] = c + } + + // mutable.LongMap is in a similar situation as LongMap and IntMap + implicit def mutableLongMapIsMap[V0]: IsMap[mutable.LongMap[V0]] { type K = Long; type V = V0; type C = mutable.LongMap[V0] } = + new IsMap[mutable.LongMap[V0]] { + type K = Long + type V = V0 + type C = mutable.LongMap[V0] + def apply(c: mutable.LongMap[V0]): MapOps[Long, V0, Tupled[Iterable]#Ap, mutable.LongMap[V0]] = c + } + + +} diff --git a/tests/pos-special/stdlib/collection/generic/IsSeq.scala b/tests/pos-special/stdlib/collection/generic/IsSeq.scala index 84fcd7be14df..8ad344c4d4fc 100644 --- a/tests/pos-special/stdlib/collection/generic/IsSeq.scala +++ b/tests/pos-special/stdlib/collection/generic/IsSeq.scala @@ -14,6 +14,9 @@ package scala.collection package generic import scala.reflect.ClassTag +import language.experimental.captureChecking +import language.experimental.captureChecking +import scala.annotation.unchecked.uncheckedCaptures /** Type class witnessing that a collection representation type `Repr` has * elements of type `A` and has a conversion to `SeqOps[A, Iterable, C]`, for @@ -51,23 +54,26 @@ object IsSeq { implicit def seqOpsIsSeq[CC0[X] <: SeqOps[X, Iterable, CC0[X]], A0]: IsSeq[CC0[A0]] { type A = A0; type C = CC0[A0] } = seqOpsIsSeqVal.asInstanceOf[IsSeq[CC0[A0]] { type A = A0; type C = CC0[A0] }] -/* Under cc, views are not Seqs and can't use SeqOps. - - implicit def seqViewIsSeq[CC0[X] <: SeqView[X], A0]: IsSeq[CC0[A0]] { type A = A0; type C = View[A0] } = - new IsSeq[CC0[A0]] { + /** !!! Under cc, views are not Seqs and can't use SeqOps. + * So this should be renamed to seqViewIsIterable + */ + implicit def seqViewIsSeq[CC0[X] <: SeqView[X], A0]: IsIterable[CC0[A0]] { type A = A0; type C = View[A0] } = + new IsIterable[CC0[A0]] { type A = A0 type C = View[A] - def apply(coll: CC0[A0]): SeqOps[A0, View, View[A0]] = coll + def apply(coll: CC0[A0]): IterableOps[A0, View, View[A0]] = coll } - implicit val stringViewIsSeq: IsSeq[StringView] { type A = Char; type C = View[Char] } = - new IsSeq[StringView] { + /** !!! Under cc, views are not Seqs and can't use SeqOps. + * So this should be renamed to stringViewIsIterable + */ + implicit val stringViewIsSeq: IsIterable[StringView] { type A = Char; type C = View[Char] } = + new IsIterable[StringView] { type A = Char type C = View[Char] - def apply(coll: StringView): SeqOps[Char, View, View[Char]] = coll + def apply(coll: StringView): IterableOps[Char, View, View[Char]] = coll } -*/ implicit val stringIsSeq: IsSeq[String] { type A = Char; type C = String } = new IsSeq[String] { type A = Char @@ -78,7 +84,7 @@ object IsSeq { def apply(i: Int): Char = s.charAt(i) def toIterable: Iterable[Char] = new immutable.WrappedString(s) protected[this] def coll: String = s - protected[this] def fromSpecific(coll: IterableOnce[Char]): String = coll.iterator.mkString + protected[this] def fromSpecific(coll: IterableOnce[Char]^): String = coll.iterator.mkString def iterableFactory: FreeSeqFactory[immutable.ArraySeq] = immutable.ArraySeq.untagged override def empty: String = "" protected[this] def newSpecificBuilder: mutable.Builder[Char, String] = new StringBuilder @@ -86,7 +92,7 @@ object IsSeq { } } - implicit def arrayIsSeq[A0 : ClassTag]: IsSeq[Array[A0]] { type A = A0; type C = Array[A0] } = + implicit def arrayIsSeq[sealed A0 : ClassTag]: IsSeq[Array[A0]] { type A = A0; type C = Array[A0] } = new IsSeq[Array[A0]] { type A = A0 type C = Array[A0] @@ -94,9 +100,9 @@ object IsSeq { new SeqOps[A, mutable.ArraySeq, Array[A]] { def apply(i: Int): A = a(i) def length: Int = a.length - def toIterable: Iterable[A] = mutable.ArraySeq.make(a) + def toIterable: Iterable[A] = mutable.ArraySeq.make[A @uncheckedCaptures](a) protected def coll: Array[A] = a - protected def fromSpecific(coll: IterableOnce[A]): Array[A] = Array.from(coll) + protected def fromSpecific(coll: IterableOnce[A]^): Array[A] = Array.from(coll) def iterableFactory: FreeSeqFactory[mutable.ArraySeq] = mutable.ArraySeq.untagged override def empty: Array[A] = Array.empty[A] protected def newSpecificBuilder: mutable.Builder[A, Array[A]] = Array.newBuilder diff --git a/tests/pos-special/stdlib/collection/generic/Subtractable.scala b/tests/pos-special/stdlib/collection/generic/Subtractable.scala new file mode 100644 index 000000000000..2c0967dbaf4b --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/Subtractable.scala @@ -0,0 +1,63 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala +package collection +package generic +import language.experimental.captureChecking + +/** This trait represents collection-like objects that can be reduced + * using a '+' operator. It defines variants of `-` and `--` + * as convenience methods in terms of single-element removal `-`. + * + * @tparam A the type of the elements of the $coll. + * @tparam Repr the type of the $coll itself + * @define coll collection + * @define Coll Subtractable + */ +@deprecated("Subtractable is deprecated. This is now implemented as part of SetOps, MapOps, etc.", "2.13.0") +trait Subtractable[A, +Repr <: Subtractable[A, Repr]] { self => + + /** The representation object of type `Repr` which contains the collection's elements + */ + protected def repr: Repr + + /** Creates a new $coll from this $coll with an element removed. + * @param elem the element to remove + * @return a new collection that contains all elements of the current $coll + * except one less occurrence of `elem`. + */ + def -(elem: A): Repr + + /** Creates a new $coll from this $coll with some elements removed. + * + * This method takes two or more elements to be removed. Another overloaded + * variant of this method handles the case where a single element is + * removed. + * @param elem1 the first element to remove. + * @param elem2 the second element to remove. + * @param elems the remaining elements to remove. + * @return a new $coll that contains all elements of the current $coll + * except one less occurrence of each of the given elements. + */ + def -(elem1: A, elem2: A, elems: A*): Repr = + this - elem1 - elem2 -- elems + + /** Creates a new $coll from this $coll by removing all elements of another + * collection. + * + * @param xs the collection containing the removed elements. + * @return a new $coll that contains all elements of the current $coll + * except one less occurrence of each of the elements of `elems`. + */ + def --(xs: IterableOnce[A]): Repr = (repr /: xs.iterator) (_ - _) +} diff --git a/tests/pos-special/stdlib/collection/generic/package.scala b/tests/pos-special/stdlib/collection/generic/package.scala new file mode 100644 index 000000000000..0ba67c1bf76e --- /dev/null +++ b/tests/pos-special/stdlib/collection/generic/package.scala @@ -0,0 +1,35 @@ +/* + * Scala (https://www.scala-lang.org) + * + * Copyright EPFL and Lightbend, Inc. + * + * Licensed under Apache License 2.0 + * (http://www.apache.org/licenses/LICENSE-2.0). + * + * See the NOTICE file distributed with this work for + * additional information regarding copyright ownership. + */ + +package scala.collection +import language.experimental.captureChecking + + +package object generic { + @deprecated("Clearable was moved from collection.generic to collection.mutable", "2.13.0") + type Clearable = scala.collection.mutable.Clearable + + @deprecated("Use scala.collection.BuildFrom instead", "2.13.0") + type CanBuildFrom[-From, -A, +C] = scala.collection.BuildFrom[From, A, C] + + @deprecated("Growable was moved from collection.generic to collection.mutable", "2.13.0") + type Growable[-A] = scala.collection.mutable.Growable[A] + + @deprecated("Shrinkable was moved from collection.generic to collection.mutable", "2.13.0") + type Shrinkable[-A] = scala.collection.mutable.Shrinkable[A] + + @deprecated("Use IsIterable instead", "2.13.0") + type IsTraversableLike[Repr] = IsIterable[Repr] + + @deprecated("Use IsIterableOnce instead", "2.13.0") + type IsTraversableOnce[Repr] = IsIterableOnce[Repr] +} From 868d65bf0e27e614dafcd06ec5de3eab52a1d937 Mon Sep 17 00:00:00 2001 From: odersky Date: Fri, 3 Nov 2023 11:14:12 +0100 Subject: [PATCH 85/89] Drop an unsafeAssumePure in Iterator --- tests/pos-special/stdlib/collection/Iterator.scala | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/tests/pos-special/stdlib/collection/Iterator.scala b/tests/pos-special/stdlib/collection/Iterator.scala index cf722235008c..993e2fc0cfea 100644 --- a/tests/pos-special/stdlib/collection/Iterator.scala +++ b/tests/pos-special/stdlib/collection/Iterator.scala @@ -17,7 +17,6 @@ import scala.annotation.tailrec import scala.annotation.unchecked.{uncheckedVariance, uncheckedCaptures} import scala.runtime.Statics import language.experimental.captureChecking -import caps.unsafe.unsafeAssumePure import annotation.unchecked.uncheckedCaptures @@ -1146,9 +1145,7 @@ object Iterator extends IterableFactory[Iterator] { * Nested ConcatIterators are merged to avoid blowing the stack. */ private final class ConcatIterator[+A](val from: Iterator[A]^) extends AbstractIterator[A] { - private var current: Iterator[A @uncheckedCaptures] = from.unsafeAssumePure - // This should be Iteratpr[A]^, but fails since mutable variables can't capture cap. - // To do better we'd need to track nesting levels for universal capabiltities. + private var current: Iterator[A @uncheckedCaptures]^{cap[ConcatIterator]} = from private var tail: ConcatIteratorCell[A @uncheckedVariance @uncheckedCaptures] = null private var last: ConcatIteratorCell[A @uncheckedVariance @uncheckedCaptures] = null private var currentHasNextChecked = false From f4066c02a14fabd41c2356deaf9e2bcaaaf6f0ce Mon Sep 17 00:00:00 2001 From: odersky Date: Fri, 3 Nov 2023 17:52:22 +0100 Subject: [PATCH 86/89] Better error message for capture errors involving self types --- .../src/dotty/tools/dotc/cc/CheckCaptures.scala | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index ae9a6eaff83e..ac6bf0252e47 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -263,11 +263,12 @@ class CheckCaptures extends Recheck, SymTransformer: pos, provenance) /** Check subcapturing `cs1 <: cs2`, report error on failure */ - def checkSubset(cs1: CaptureSet, cs2: CaptureSet, pos: SrcPos, provenance: => String = "")(using Context) = + def checkSubset(cs1: CaptureSet, cs2: CaptureSet, pos: SrcPos, + provenance: => String = "", cs1description: String = "")(using Context) = checkOK( cs1.subCaptures(cs2, frozen = false), - if cs1.elems.size == 1 then i"reference ${cs1.elems.toList.head} is not" - else i"references $cs1 are not all", + if cs1.elems.size == 1 then i"reference ${cs1.elems.toList.head}$cs1description is not" + else i"references $cs1$cs1description are not all", pos, provenance) /** The current environment */ @@ -683,9 +684,15 @@ class CheckCaptures extends Recheck, SymTransformer: if !param.hasAnnotation(defn.ConstructorOnlyAnnot) then checkSubset(param.termRef.captureSet, thisSet, param.srcPos) // (3) for pureBase <- cls.pureBaseClass do // (4) + def selfType = impl.body + .collect: + case TypeDef(tpnme.SELF, rhs) => rhs + .headOption + .getOrElse(tree) + .orElse(tree) checkSubset(thisSet, CaptureSet.empty.withDescription(i"of pure base class $pureBase"), - tree.srcPos) + selfType.srcPos, cs1description = " captured by this self type") super.recheckClassDef(tree, impl, cls) finally curEnv = saved From e22744de00e65fa33622f3cf09b09b4a0f8dd174 Mon Sep 17 00:00:00 2001 From: odersky Date: Sat, 4 Nov 2023 10:54:57 +0100 Subject: [PATCH 87/89] Add sealed refs test and fix check files of other tests --- tests/neg-custom-args/captures/cc-this.check | 2 +- tests/neg-custom-args/captures/cc-this2.check | 14 +++++-- .../captures/cc-this2/D_2.scala | 2 +- .../captures/exception-definitions.check | 9 ++-- .../captures/exception-definitions.scala | 4 +- .../captures/sealed-refs.scala | 42 +++++++++++++++++++ 6 files changed, 60 insertions(+), 13 deletions(-) create mode 100644 tests/neg-custom-args/captures/sealed-refs.scala diff --git a/tests/neg-custom-args/captures/cc-this.check b/tests/neg-custom-args/captures/cc-this.check index 335302c5c259..070e815d6d45 100644 --- a/tests/neg-custom-args/captures/cc-this.check +++ b/tests/neg-custom-args/captures/cc-this.check @@ -12,4 +12,4 @@ -- Error: tests/neg-custom-args/captures/cc-this.scala:17:8 ------------------------------------------------------------ 17 | class C4(val f: () => Int) extends C3 // error | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - | reference (C4.this.f : () => Int) is not included in the allowed capture set {} of pure base class class C3 + |reference (C4.this.f : () => Int) captured by this self type is not included in the allowed capture set {} of pure base class class C3 diff --git a/tests/neg-custom-args/captures/cc-this2.check b/tests/neg-custom-args/captures/cc-this2.check index 5e43a45b67f5..bd9a1085d262 100644 --- a/tests/neg-custom-args/captures/cc-this2.check +++ b/tests/neg-custom-args/captures/cc-this2.check @@ -1,6 +1,12 @@ --- Error: tests/neg-custom-args/captures/cc-this2/D_2.scala:2:6 -------------------------------------------------------- +-- Error: tests/neg-custom-args/captures/cc-this2/D_2.scala:3:8 -------------------------------------------------------- +3 | this: D^ => // error + | ^^ + |reference (caps.cap : caps.Cap) captured by this self type is not included in the allowed capture set {} of pure base class class C +-- [E058] Type Mismatch Error: tests/neg-custom-args/captures/cc-this2/D_2.scala:2:6 ----------------------------------- 2 |class D extends C: // error - |^ - |reference (caps.cap : caps.Cap) is not included in the allowed capture set {} of pure base class class C -3 | this: D^ => + | ^ + | illegal inheritance: self type D^ of class D does not conform to self type C + | of parent class C + | + | longer explanation available when compiling with `-explain` diff --git a/tests/neg-custom-args/captures/cc-this2/D_2.scala b/tests/neg-custom-args/captures/cc-this2/D_2.scala index b22e5e456092..de1a722f73a9 100644 --- a/tests/neg-custom-args/captures/cc-this2/D_2.scala +++ b/tests/neg-custom-args/captures/cc-this2/D_2.scala @@ -1,3 +1,3 @@ class D extends C: // error - this: D^ => + this: D^ => // error diff --git a/tests/neg-custom-args/captures/exception-definitions.check b/tests/neg-custom-args/captures/exception-definitions.check index 4b1fe0273f52..72b88f252e59 100644 --- a/tests/neg-custom-args/captures/exception-definitions.check +++ b/tests/neg-custom-args/captures/exception-definitions.check @@ -1,8 +1,7 @@ --- Error: tests/neg-custom-args/captures/exception-definitions.scala:2:6 ----------------------------------------------- -2 |class Err extends Exception: // error - |^ - |reference (caps.cap : caps.Cap) is not included in the allowed capture set {} of pure base class class Throwable -3 | self: Err^ => +-- Error: tests/neg-custom-args/captures/exception-definitions.scala:3:8 ----------------------------------------------- +3 | self: Err^ => // error + | ^^^^ + |reference (caps.cap : caps.Cap) captured by this self type is not included in the allowed capture set {} of pure base class class Throwable -- Error: tests/neg-custom-args/captures/exception-definitions.scala:7:12 ---------------------------------------------- 7 | val x = c // error | ^ diff --git a/tests/neg-custom-args/captures/exception-definitions.scala b/tests/neg-custom-args/captures/exception-definitions.scala index a19b751825b8..fbc9f3fd1d33 100644 --- a/tests/neg-custom-args/captures/exception-definitions.scala +++ b/tests/neg-custom-args/captures/exception-definitions.scala @@ -1,6 +1,6 @@ -class Err extends Exception: // error - self: Err^ => +class Err extends Exception: + self: Err^ => // error def test(c: Any^) = class Err2 extends Exception: diff --git a/tests/neg-custom-args/captures/sealed-refs.scala b/tests/neg-custom-args/captures/sealed-refs.scala new file mode 100644 index 000000000000..05fa483acf28 --- /dev/null +++ b/tests/neg-custom-args/captures/sealed-refs.scala @@ -0,0 +1,42 @@ +class Ref[sealed A](init: A): + this: Ref[A]^ => + private var x: A = init + def get: A = x + def set(x: A): Unit = this.x = x + +class It[X]: + this: It[X]^ => + +def f1[B1](x: B1, next: B1 -> B1) = + var r = x // ok + r = next(x) + r + +def f2[B2](x: B2, next: B2 -> B2) = + val r = Ref[B2](x) // error + r.set(next(x)) + r.get + +def g[sealed B](x: B, next: B -> B) = + val r = Ref[B](x) // ok + r.set(next(x)) + r.get + +import annotation.unchecked.uncheckedCaptures + +def h[B](x: B, next: B -> B) = + val r = Ref[B @uncheckedCaptures](x) // ok + r.set(next(x)) + r.get + +def f3[B](x: B, next: B -> B) = + val r: Ref[B^{cap[f3]}] = Ref[B^{cap[f3]}](x) // error + r.set(next(x)) + val y = r.get + () + +def f4[B](x: B, next: B -> B) = + val r: Ref[B]^{cap[f4]} = Ref[B](x) // error + r.set(next(x)) + val y = r.get + () \ No newline at end of file From cfec1d0a2a92b5a23b38f1f6219e215cf0c19d58 Mon Sep 17 00:00:00 2001 From: odersky Date: Sat, 4 Nov 2023 11:29:22 +0100 Subject: [PATCH 88/89] Simplify CapturedVars phase No need for a separate entry in the context's store; we can keep everything in the phase itself, which is more efficient and modular. --- .../tools/dotc/transform/CapturedVars.scala | 55 +++++++------------ 1 file changed, 20 insertions(+), 35 deletions(-) diff --git a/compiler/src/dotty/tools/dotc/transform/CapturedVars.scala b/compiler/src/dotty/tools/dotc/transform/CapturedVars.scala index a018bbd1a3ac..202e3d72fa25 100644 --- a/compiler/src/dotty/tools/dotc/transform/CapturedVars.scala +++ b/compiler/src/dotty/tools/dotc/transform/CapturedVars.scala @@ -13,25 +13,20 @@ import core.NameKinds.TempResultName import core.Constants._ import util.Store import dotty.tools.uncheckedNN - -import scala.compiletime.uninitialized +import ast.tpd.* +import compiletime.uninitialized /** This phase translates variables that are captured in closures to * heap-allocated refs. */ class CapturedVars extends MiniPhase with IdentityDenotTransformer: thisPhase => - import ast.tpd._ override def phaseName: String = CapturedVars.name override def description: String = CapturedVars.description - private[this] var Captured: Store.Location[util.ReadOnlySet[Symbol]] = uninitialized - private def captured(using Context) = ctx.store(Captured) - - override def initContext(ctx: FreshContext): Unit = - Captured = ctx.addLocation(util.ReadOnlySet.empty) + private val captured = util.HashSet[Symbol]() private class RefInfo(using Context) { /** The classes for which a Ref type exists. */ @@ -57,33 +52,10 @@ class CapturedVars extends MiniPhase with IdentityDenotTransformer: myRefInfo.uncheckedNN } - private class CollectCaptured extends TreeTraverser { - private val captured = util.HashSet[Symbol]() - def traverse(tree: Tree)(using Context) = tree match { - case id: Ident => - val sym = id.symbol - if (sym.is(Mutable, butNot = Method) && sym.owner.isTerm) { - val enclMeth = ctx.owner.enclosingMethod - if (sym.enclosingMethod != enclMeth) { - report.log(i"capturing $sym in ${sym.enclosingMethod}, referenced from $enclMeth") - captured += sym - } - } - case _ => - traverseChildren(tree) - } - def runOver(tree: Tree)(using Context): util.ReadOnlySet[Symbol] = { - traverse(tree) - captured - } - } - - override def prepareForUnit(tree: Tree)(using Context): Context = { - val captured = atPhase(thisPhase) { - CollectCaptured().runOver(ctx.compilationUnit.tpdTree) - } - ctx.fresh.updateStore(Captured, captured) - } + override def prepareForUnit(tree: Tree)(using Context): Context = + captured.clear() + atPhase(thisPhase)(CapturedVars.collect(captured)).traverse(tree) + ctx /** The {Volatile|}{Int|Double|...|Object}Ref class corresponding to the class `cls`, * depending on whether the reference should be @volatile @@ -143,3 +115,16 @@ class CapturedVars extends MiniPhase with IdentityDenotTransformer: object CapturedVars: val name: String = "capturedVars" val description: String = "represent vars captured by closures as heap objects" + + def collect(captured: util.HashSet[Symbol]): TreeTraverser = new: + def traverse(tree: Tree)(using Context) = tree match + case id: Ident => + val sym = id.symbol + if sym.is(Mutable, butNot = Method) && sym.owner.isTerm then + val enclMeth = ctx.owner.enclosingMethod + if sym.enclosingMethod != enclMeth then + report.log(i"capturing $sym in ${sym.enclosingMethod}, referenced from $enclMeth") + captured += sym + case _ => + traverseChildren(tree) +end CapturedVars From 5e49b124f5e735ecfbbaf48963d184d09c090194 Mon Sep 17 00:00:00 2001 From: odersky Date: Sat, 4 Nov 2023 12:20:15 +0100 Subject: [PATCH 89/89] Refine isParametric tests Mutable variables can appeal to parametricty only if they are not captured. We use "not captured by any closure" as a sound approximation for that, since variables themselves are currently not tracked, so we cannot use soemthing more finegrained. --- .../dotty/tools/dotc/cc/CheckCaptures.scala | 89 +++++++++++++++---- tests/neg-custom-args/captures/buffers.check | 6 +- tests/neg-custom-args/captures/levels.check | 4 +- .../captures/sealed-leaks.check | 50 +++++++++++ .../captures/sealed-leaks.scala | 32 ++++++- .../stdlib/collection/Iterator.scala | 2 +- .../immutable/LazyListIterable.scala | 20 ++--- .../collection/immutable/TreeSeqMap.scala | 2 +- .../stdlib/collection/immutable/Vector.scala | 2 +- 9 files changed, 173 insertions(+), 34 deletions(-) create mode 100644 tests/neg-custom-args/captures/sealed-leaks.check diff --git a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala index ac6bf0252e47..a49bd9f79351 100644 --- a/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala +++ b/compiler/src/dotty/tools/dotc/cc/CheckCaptures.scala @@ -16,7 +16,7 @@ import typer.ErrorReporting.{Addenda, err} import typer.ProtoTypes.{AnySelectionProto, LhsProto} import util.{SimpleIdentitySet, EqHashMap, EqHashSet, SrcPos, Property} import transform.SymUtils.* -import transform.{Recheck, PreRecheck} +import transform.{Recheck, PreRecheck, CapturedVars} import Recheck.* import scala.collection.mutable import CaptureSet.{withCaptureSetsExplained, IdempotentCaptRefMap, CompareResult} @@ -149,15 +149,25 @@ object CheckCaptures: private val seen = new EqHashSet[TypeRef] + /** Check that there is at least one method containing carrier and defined + * in the scope of tparam. E.g. this is OK: + * def f[T] = { ... var x: T ... } + * So is this: + * class C[T] { def f() = { class D { var x: T }}} + * But this is not OK: + * class C[T] { object o { var x: T }} + */ extension (tparam: Symbol) def isParametricIn(carrier: Symbol): Boolean = - val encl = carrier.maybeOwner.enclosingMethodOrClass - if encl.isClass then tparam.isParametricIn(encl) - else - def recur(encl: Symbol): Boolean = - if tparam.owner == encl then true - else if encl.isStatic || !encl.exists then false - else recur(encl.owner.enclosingMethodOrClass) - recur(encl) + carrier.exists && { + val encl = carrier.owner.enclosingMethodOrClass + if encl.isClass then tparam.isParametricIn(encl) + else + def recur(encl: Symbol): Boolean = + if tparam.owner == encl then true + else if encl.isStatic || !encl.exists then false + else recur(encl.owner.enclosingMethodOrClass) + recur(encl) + } def traverse(t: Type) = t.dealiasKeepAnnots match @@ -168,9 +178,12 @@ object CheckCaptures: t.info match case TypeBounds(_, hi) if !t.isSealed && !t.symbol.isParametricIn(carrier) => if hi.isAny then + val detailStr = + if t eq tp then "variable" + else i"refers to the type variable $t, which" report.error( em"""$what cannot $have $tp since - |that type refers to the type variable $t, which is not sealed. + |that type $detailStr is not sealed. |$addendum""", pos) else @@ -549,7 +562,7 @@ class CheckCaptures extends Recheck, SymTransformer: for case (arg: TypeTree, formal, pname) <- args.lazyZip(polyType.paramRefs).lazyZip((polyType.paramNames)) do if formal.isSealed then def where = if fn.symbol.exists then i" in an argument of ${fn.symbol}" else "" - disallowRootCapabilitiesIn(arg.knownType, fn.symbol, + disallowRootCapabilitiesIn(arg.knownType, NoSymbol, i"Sealed type variable $pname", "be instantiated to", i"This is often caused by a local capability$where\nleaking as part of its result.", tree.srcPos) @@ -590,13 +603,58 @@ class CheckCaptures extends Recheck, SymTransformer: openClosures = openClosures.tail end recheckClosureBlock + /** Maps mutable variables to the symbols that capture them (in the + * CheckCaptures sense, i.e. symbol is referred to from a different method + * than the one it is defined in). + */ + private val capturedBy = util.HashMap[Symbol, Symbol]() + + /** Maps anonymous functions appearing as function arguments to + * the function that is called. + */ + private val anonFunCallee = util.HashMap[Symbol, Symbol]() + + /** Populates `capturedBy` and `anonFunCallee`. Called by `checkUnit`. + */ + private def collectCapturedMutVars(using Context) = new TreeTraverser: + def traverse(tree: Tree)(using Context) = tree match + case id: Ident => + val sym = id.symbol + if sym.is(Mutable, butNot = Method) && sym.owner.isTerm then + val enclMeth = ctx.owner.enclosingMethod + if sym.enclosingMethod != enclMeth then + capturedBy(sym) = enclMeth + case Apply(fn, args) => + for case closureDef(mdef) <- args do + anonFunCallee(mdef.symbol) = fn.symbol + traverseChildren(tree) + case Inlined(_, bindings, expansion) => + traverse(bindings) + traverse(expansion) + case mdef: DefDef => + if !mdef.symbol.isInlineMethod then traverseChildren(tree) + case _ => + traverseChildren(tree) + override def recheckValDef(tree: ValDef, sym: Symbol)(using Context): Type = try if sym.is(Module) then sym.info // Modules are checked by checking the module class else if sym.is(Mutable) && !sym.hasAnnotation(defn.UncheckedCapturesAnnot) then - disallowRootCapabilitiesIn(tree.tpt.knownType, sym, - i"mutable $sym", "have type", "", sym.srcPos) + val (carrier, addendum) = capturedBy.get(sym) match + case Some(encl) => + val enclStr = + if encl.isAnonymousFunction then + val location = anonFunCallee.get(encl) match + case Some(meth) if meth.exists => i" argument in a call to $meth" + case _ => "" + s"an anonymous function$location" + else encl.show + (NoSymbol, i"\nNote that $sym does not count as local since it is captured by $enclStr") + case _ => + (sym, "") + disallowRootCapabilitiesIn( + tree.tpt.knownType, carrier, i"Mutable $sym", "have type", addendum, sym.srcPos) checkInferredResult(super.recheckValDef(tree, sym), tree) finally if !sym.is(Param) then @@ -1170,11 +1228,12 @@ class CheckCaptures extends Recheck, SymTransformer: private val setup: SetupAPI = thisPhase.prev.asInstanceOf[Setup] override def checkUnit(unit: CompilationUnit)(using Context): Unit = - setup.setupUnit(ctx.compilationUnit.tpdTree, completeDef) + setup.setupUnit(unit.tpdTree, completeDef) + collectCapturedMutVars.traverse(unit.tpdTree) if ctx.settings.YccPrintSetup.value then val echoHeader = "[[syntax tree at end of cc setup]]" - val treeString = show(ctx.compilationUnit.tpdTree) + val treeString = show(unit.tpdTree) report.echo(s"$echoHeader\n$treeString\n") withCaptureSetsExplained: diff --git a/tests/neg-custom-args/captures/buffers.check b/tests/neg-custom-args/captures/buffers.check index cdb7baa852fb..07acea3c48e3 100644 --- a/tests/neg-custom-args/captures/buffers.check +++ b/tests/neg-custom-args/captures/buffers.check @@ -1,7 +1,7 @@ -- Error: tests/neg-custom-args/captures/buffers.scala:11:6 ------------------------------------------------------------ 11 | var elems: Array[A] = new Array[A](10) // error // error | ^ - | mutable variable elems cannot have type Array[A] since + | Mutable variable elems cannot have type Array[A] since | that type refers to the type variable A, which is not sealed. -- Error: tests/neg-custom-args/captures/buffers.scala:16:38 ----------------------------------------------------------- 16 | def make[A: ClassTag](xs: A*) = new ArrayBuffer: // error @@ -14,13 +14,13 @@ 11 | var elems: Array[A] = new Array[A](10) // error // error | ^^^^^^^^ | Array cannot have element type A since - | that type refers to the type variable A, which is not sealed. + | that type variable is not sealed. | Since arrays are mutable, they have to be treated like variables, | so their element type must be sealed. -- Error: tests/neg-custom-args/captures/buffers.scala:22:9 ------------------------------------------------------------ 22 | val x: Array[A] = new Array[A](10) // error | ^^^^^^^^ | Array cannot have element type A since - | that type refers to the type variable A, which is not sealed. + | that type variable is not sealed. | Since arrays are mutable, they have to be treated like variables, | so their element type must be sealed. diff --git a/tests/neg-custom-args/captures/levels.check b/tests/neg-custom-args/captures/levels.check index f91f90fb652f..c0cc7f0a759c 100644 --- a/tests/neg-custom-args/captures/levels.check +++ b/tests/neg-custom-args/captures/levels.check @@ -1,8 +1,8 @@ -- Error: tests/neg-custom-args/captures/levels.scala:6:16 ------------------------------------------------------------- 6 | private var v: T = init // error | ^ - | mutable variable v cannot have type T since - | that type refers to the type variable T, which is not sealed. + | Mutable variable v cannot have type T since + | that type variable is not sealed. -- Error: tests/neg-custom-args/captures/levels.scala:17:13 ------------------------------------------------------------ 17 | val _ = Ref[String => String]((x: String) => x) // error | ^^^^^^^^^^^^^^^^^^^^^ diff --git a/tests/neg-custom-args/captures/sealed-leaks.check b/tests/neg-custom-args/captures/sealed-leaks.check new file mode 100644 index 000000000000..f7098eba32b6 --- /dev/null +++ b/tests/neg-custom-args/captures/sealed-leaks.check @@ -0,0 +1,50 @@ +-- [E129] Potential Issue Warning: tests/neg-custom-args/captures/sealed-leaks.scala:31:6 ------------------------------ +31 | () + | ^^ + | A pure expression does nothing in statement position + | + | longer explanation available when compiling with `-explain` +-- Error: tests/neg-custom-args/captures/sealed-leaks.scala:12:27 ------------------------------------------------------ +12 | val later2 = usingLogFile[(() => Unit) | Null] { f => () => f.write(0) } // error + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | Sealed type variable T cannot be instantiated to (() => Unit) | Null since + | that type captures the root capability `cap`. + | This is often caused by a local capability in an argument of method usingLogFile + | leaking as part of its result. +-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/sealed-leaks.scala:19:26 --------------------------------- +19 | usingLogFile { f => x = f } // error + | ^ + | Found: (f : java.io.FileOutputStream^) + | Required: (java.io.FileOutputStream | Null)^{cap[Test2]} + | + | longer explanation available when compiling with `-explain` +-- Error: tests/neg-custom-args/captures/sealed-leaks.scala:30:10 ------------------------------------------------------ +30 | var x: T = y // error + | ^ + | Mutable variable x cannot have type T since + | that type variable is not sealed. +-- Error: tests/neg-custom-args/captures/sealed-leaks.scala:39:8 ------------------------------------------------------- +39 | var x: T = y // error + | ^ + | Mutable variable x cannot have type T since + | that type variable is not sealed. + | + | Note that variable x does not count as local since it is captured by an anonymous function +-- Error: tests/neg-custom-args/captures/sealed-leaks.scala:43:8 ------------------------------------------------------- +43 | var x: T = y // error + | ^ + |Mutable variable x cannot have type T since + |that type variable is not sealed. + | + |Note that variable x does not count as local since it is captured by an anonymous function argument in a call to method identity +-- Error: tests/neg-custom-args/captures/sealed-leaks.scala:47:8 ------------------------------------------------------- +47 | var x: T = y // error + | ^ + | Mutable variable x cannot have type T since + | that type variable is not sealed. + | + | Note that variable x does not count as local since it is captured by method foo +-- Error: tests/neg-custom-args/captures/sealed-leaks.scala:11:14 ------------------------------------------------------ +11 | val later = usingLogFile { f => () => f.write(0) } // error + | ^^^^^^^^^^^^ + | local reference f leaks into outer capture set of type parameter T of method usingLogFile diff --git a/tests/neg-custom-args/captures/sealed-leaks.scala b/tests/neg-custom-args/captures/sealed-leaks.scala index a7acf77b5678..2555ba8a3e07 100644 --- a/tests/neg-custom-args/captures/sealed-leaks.scala +++ b/tests/neg-custom-args/captures/sealed-leaks.scala @@ -18,4 +18,34 @@ def Test2 = usingLogFile { f => x = f } // error - later() \ No newline at end of file + later() + +def Test3 = + def f[T](y: T) = + var x: T = y + () + + class C[T](y: T): + object o: + var x: T = y // error + () + + class C2[T](y: T): + def f = + var x: T = y // ok + () + + def g1[T](y: T): T => Unit = + var x: T = y // error + y => x = y + + def g2[T](y: T): T => Unit = + var x: T = y // error + identity(y => x = y) + + def g3[T](y: T): Unit = + var x: T = y // error + def foo = + x = y + () + diff --git a/tests/pos-special/stdlib/collection/Iterator.scala b/tests/pos-special/stdlib/collection/Iterator.scala index 993e2fc0cfea..90fd387069b0 100644 --- a/tests/pos-special/stdlib/collection/Iterator.scala +++ b/tests/pos-special/stdlib/collection/Iterator.scala @@ -868,7 +868,7 @@ trait Iterator[+A] extends IterableOnce[A] with IterableOnceOps[A, Iterator, Ite */ def duplicate: (Iterator[A]^{this}, Iterator[A]^{this}) = { val gap = new scala.collection.mutable.Queue[A @uncheckedCaptures] - var ahead: Iterator[A] = null + var ahead: Iterator[A @uncheckedCaptures] = null // ahead is captured by Partner, so A is not recognized as parametric class Partner extends AbstractIterator[A] { override def knownSize: Int = self.synchronized { val thisSize = self.knownSize diff --git a/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala b/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala index 8d804bad13de..5684130b6048 100644 --- a/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala +++ b/tests/pos-special/stdlib/collection/immutable/LazyListIterable.scala @@ -852,9 +852,9 @@ final class LazyListIterable[+A] private(private[this] var lazyState: () => Lazy else if (!isEmpty) { b.append(head) var cursor = this - @inline def appendCursorElement(): Unit = b.append(sep).append(cursor.head) + inline def appendCursorElement(): Unit = b.append(sep).append(cursor.head) var scout = tail - @inline def scoutNonEmpty: Boolean = scout.stateDefined && !scout.isEmpty + inline def scoutNonEmpty: Boolean = scout.stateDefined && !scout.isEmpty if ((cursor ne scout) && (!scout.stateDefined || (cursor.state ne scout.state))) { cursor = scout if (scoutNonEmpty) { @@ -998,7 +998,7 @@ object LazyListIterable extends IterableFactory[LazyListIterable] { private def filterImpl[A](ll: LazyListIterable[A]^, p: A => Boolean, isFlipped: Boolean): LazyListIterable[A]^{ll, p} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD - var restRef = ll // val restRef = new ObjectRef(ll) + var restRef: LazyListIterable[A @uncheckedCaptures]^{cap[filterImpl]} = ll // restRef is captured by closure arg to newLL, so A is not recognized as parametric newLL { var elem: A = null.asInstanceOf[A] var found = false @@ -1015,7 +1015,7 @@ object LazyListIterable extends IterableFactory[LazyListIterable] { private def collectImpl[A, B](ll: LazyListIterable[A]^, pf: PartialFunction[A, B]^): LazyListIterable[B]^{ll, pf} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD - var restRef = ll // val restRef = new ObjectRef(ll) + var restRef: LazyListIterable[A @uncheckedCaptures]^{cap[collectImpl]} = ll // restRef is captured by closure arg to newLL, so A is not recognized as parametric newLL { val marker = Statics.pfMarker val toMarker = anyToMarker.asInstanceOf[A => B] // safe because Function1 is erased @@ -1034,9 +1034,9 @@ object LazyListIterable extends IterableFactory[LazyListIterable] { private def flatMapImpl[A, B](ll: LazyListIterable[A]^, f: A => IterableOnce[B]^): LazyListIterable[B]^{ll, f} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD - var restRef = ll // val restRef = new ObjectRef(ll) + var restRef: LazyListIterable[A @uncheckedCaptures]^{cap[flatMapImpl]} = ll // restRef is captured by closure arg to newLL, so A is not recognized as parametric newLL { - var it: Iterator[B]^{ll, f} = null + var it: Iterator[B @uncheckedCaptures]^{ll, f} = null var itHasNext = false var rest = restRef // var rest = restRef.elem while (!itHasNext && !rest.isEmpty) { @@ -1058,7 +1058,7 @@ object LazyListIterable extends IterableFactory[LazyListIterable] { private def dropImpl[A](ll: LazyListIterable[A]^, n: Int): LazyListIterable[A]^{ll} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD - var restRef = ll // val restRef = new ObjectRef(ll) + var restRef: LazyListIterable[A @uncheckedCaptures]^{cap[dropImpl]} = ll // restRef is captured by closure arg to newLL, so A is not recognized as parametric var iRef = n // val iRef = new IntRef(n) newLL { var rest = restRef // var rest = restRef.elem @@ -1075,7 +1075,7 @@ object LazyListIterable extends IterableFactory[LazyListIterable] { private def dropWhileImpl[A](ll: LazyListIterable[A]^, p: A => Boolean): LazyListIterable[A]^{ll, p} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD - var restRef = ll // val restRef = new ObjectRef(ll) + var restRef: LazyListIterable[A @uncheckedCaptures]^{cap[dropWhileImpl]} = ll // restRef is captured by closure arg to newLL, so A is not recognized as parametric newLL { var rest = restRef // var rest = restRef.elem while (!rest.isEmpty && p(rest.head)) { @@ -1088,8 +1088,8 @@ object LazyListIterable extends IterableFactory[LazyListIterable] { private def takeRightImpl[A](ll: LazyListIterable[A]^, n: Int): LazyListIterable[A]^{ll} = { // DO NOT REFERENCE `ll` ANYWHERE ELSE, OR IT WILL LEAK THE HEAD - var restRef = ll // val restRef = new ObjectRef(ll) - var scoutRef = ll // val scoutRef = new ObjectRef(ll) + var restRef: LazyListIterable[A @uncheckedCaptures]^{cap[takeRightImpl]} = ll // restRef is captured by closure arg to newLL, so A is not recognized as parametric + var scoutRef: LazyListIterable[A @uncheckedCaptures]^{cap[takeRightImpl]} = ll // same situation var remainingRef = n // val remainingRef = new IntRef(n) newLL { var scout = scoutRef // var scout = scoutRef.elem diff --git a/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala b/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala index d7cceb54cca3..91233669e5ca 100644 --- a/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala +++ b/tests/pos-special/stdlib/collection/immutable/TreeSeqMap.scala @@ -609,7 +609,7 @@ object TreeSeqMap extends MapFactory[TreeSeqMap] { } final def splitAt(n: Int): (Ordering[T], Ordering[T]) = { - var rear = Ordering.empty[T] + var rear: Ordering[T @uncheckedCaptures] = Ordering.empty[T] var i = n (modifyOrRemove { (o, v) => i -= 1 diff --git a/tests/pos-special/stdlib/collection/immutable/Vector.scala b/tests/pos-special/stdlib/collection/immutable/Vector.scala index 1bde30406fd9..d9d33add512d 100644 --- a/tests/pos-special/stdlib/collection/immutable/Vector.scala +++ b/tests/pos-special/stdlib/collection/immutable/Vector.scala @@ -229,7 +229,7 @@ sealed abstract class Vector[+A] private[immutable] (private[immutable] final va // k >= 0, k = suffix.knownSize val tinyAppendLimit = 4 + vectorSliceCount if (k < tinyAppendLimit) { - var v: Vector[B] = this + var v: Vector[B @uncheckedCaptures] = this suffix match { case it: Iterable[_] => it.asInstanceOf[Iterable[B]].foreach(x => v = v.appended(x)) case _ => suffix.iterator.foreach(x => v = v.appended(x))