From 64d151a0466522e8b5e0a887938d374dec2882fa Mon Sep 17 00:00:00 2001
From: Dale Wijnand <dale.wijnand@gmail.com>
Date: Wed, 14 Jun 2023 18:20:26 +0100
Subject: [PATCH 1/2] Fix hasMatchingMember handling NoDenotation
---
compiler/src/dotty/tools/dotc/core/TypeComparer.scala | 2 +-
tests/neg/i17581.check | 7 +++++++
tests/neg/i17581.scala | 9 +++++++++
tests/neg/i7812.scala | 2 +-
4 files changed, 18 insertions(+), 2 deletions(-)
create mode 100644 tests/neg/i17581.check
create mode 100644 tests/neg/i17581.scala
diff --git a/compiler/src/dotty/tools/dotc/core/TypeComparer.scala b/compiler/src/dotty/tools/dotc/core/TypeComparer.scala
index a0922c1f0574..264ff52d0af9 100644
--- a/compiler/src/dotty/tools/dotc/core/TypeComparer.scala
+++ b/compiler/src/dotty/tools/dotc/core/TypeComparer.scala
@@ -2021,7 +2021,7 @@ class TypeComparer(@constructorOnly initctx: Context) extends ConstraintHandling
|| (tp1.isStable && isSubType(TermRef(tp1, m.symbol), tp2.refinedInfo))
tp1.member(name) match // inlined hasAltWith for performance
- case mbr: SingleDenotation => qualifies(mbr)
+ case mbr: SingleDenotation => mbr.exists && qualifies(mbr)
case mbr => mbr hasAltWith qualifies
}
diff --git a/tests/neg/i17581.check b/tests/neg/i17581.check
new file mode 100644
index 000000000000..e21e9fd32019
--- /dev/null
+++ b/tests/neg/i17581.check
@@ -0,0 +1,7 @@
+-- [E007] Type Mismatch Error: tests/neg/i17581.scala:9:6 --------------------------------------------------------------
+9 | foo(test) // error // was NoSuchMethodException
+ | ^^^^
+ | Found: (test : Test)
+ | Required: Object{def bar: Any}
+ |
+ | longer explanation available when compiling with `-explain`
diff --git a/tests/neg/i17581.scala b/tests/neg/i17581.scala
new file mode 100644
index 000000000000..1cd86a9d39cd
--- /dev/null
+++ b/tests/neg/i17581.scala
@@ -0,0 +1,9 @@
+import scala.reflect.Selectable.reflectiveSelectable
+
+class Test
+
+def foo[A <: { def bar: Any }](ob: A) = ob.bar
+
+@main def main =
+ val test = new Test
+ foo(test) // error // was NoSuchMethodException
diff --git a/tests/neg/i7812.scala b/tests/neg/i7812.scala
index 264258fa4db3..9cbd58071bc8 100644
--- a/tests/neg/i7812.scala
+++ b/tests/neg/i7812.scala
@@ -1,3 +1,3 @@
def f(): Any = ???
var f: (UndefinedA & UndefinedB) { val x: Int } = ??? // error // error
-val a = f // error
\ No newline at end of file
+val a = f
From 4373d48d20c872a2a45514aa5e6878572fc5e179 Mon Sep 17 00:00:00 2001
From: Dale Wijnand <dale.wijnand@gmail.com>
Date: Sat, 17 Jun 2023 11:36:55 +0100
Subject: [PATCH 2/2] Introduce hasAltWithInline, to fix all usages
---
compiler/src/dotty/tools/dotc/core/Denotations.scala | 4 ++++
compiler/src/dotty/tools/dotc/core/TypeComparer.scala | 4 +---
compiler/src/dotty/tools/dotc/typer/Applications.scala | 5 +----
compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala | 4 +---
4 files changed, 7 insertions(+), 10 deletions(-)
diff --git a/compiler/src/dotty/tools/dotc/core/Denotations.scala b/compiler/src/dotty/tools/dotc/core/Denotations.scala
index 82368fd4dbf5..a535048d2e73 100644
--- a/compiler/src/dotty/tools/dotc/core/Denotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/Denotations.scala
@@ -261,6 +261,10 @@ object Denotations {
/** Does this denotation have an alternative that satisfies the predicate `p`? */
def hasAltWith(p: SingleDenotation => Boolean): Boolean
+ inline final def hasAltWithInline(inline p: SingleDenotation => Boolean): Boolean = inline this match
+ case mbr: SingleDenotation => mbr.exists && p(mbr)
+ case mbr => mbr.hasAltWith(p)
+
/** The denotation made up from the alternatives of this denotation that
* are accessible from prefix `pre`, or NoDenotation if no accessible alternative exists.
*/
diff --git a/compiler/src/dotty/tools/dotc/core/TypeComparer.scala b/compiler/src/dotty/tools/dotc/core/TypeComparer.scala
index 264ff52d0af9..6c7af839f008 100644
--- a/compiler/src/dotty/tools/dotc/core/TypeComparer.scala
+++ b/compiler/src/dotty/tools/dotc/core/TypeComparer.scala
@@ -2020,9 +2020,7 @@ class TypeComparer(@constructorOnly initctx: Context) extends ConstraintHandling
|| matchAbstractTypeMember(m.info)
|| (tp1.isStable && isSubType(TermRef(tp1, m.symbol), tp2.refinedInfo))
- tp1.member(name) match // inlined hasAltWith for performance
- case mbr: SingleDenotation => mbr.exists && qualifies(mbr)
- case mbr => mbr hasAltWith qualifies
+ tp1.member(name).hasAltWithInline(qualifies)
}
final def ensureStableSingleton(tp: Type): SingletonType = tp.stripTypeVar match {
diff --git a/compiler/src/dotty/tools/dotc/typer/Applications.scala b/compiler/src/dotty/tools/dotc/typer/Applications.scala
index 17b79ab0f801..08437a529a88 100644
--- a/compiler/src/dotty/tools/dotc/typer/Applications.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Applications.scala
@@ -1517,10 +1517,7 @@ trait Applications extends Compatibility {
&& isApplicableType(
normalize(tp.select(xname, mbr), WildcardType),
argType :: Nil, resultType)
- tp.memberBasedOnFlags(xname, required = ExtensionMethod) match {
- case mbr: SingleDenotation => qualifies(mbr)
- case mbr => mbr.hasAltWith(qualifies(_))
- }
+ tp.memberBasedOnFlags(xname, required = ExtensionMethod).hasAltWithInline(qualifies)
}
/** Drop any leading type or implicit parameter sections */
diff --git a/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala b/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala
index 8b04ca8dd75b..ad07b0ebd7a5 100644
--- a/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala
+++ b/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala
@@ -212,9 +212,7 @@ object ProtoTypes {
|| tp1.isValueType && compat.normalizedCompatible(NamedType(tp1, name, m), memberProto, keepConstraint))
// Note: can't use `m.info` here because if `m` is a method, `m.info`
// loses knowledge about `m`'s default arguments.
- mbr match // hasAltWith inlined for performance
- case mbr: SingleDenotation => mbr.exists && qualifies(mbr)
- case _ => mbr hasAltWith qualifies
+ mbr.hasAltWithInline(qualifies)
catch case ex: TypeError =>
// A scenario where this can happen is in pos/15673.scala:
// We have a type `CC[A]#C` where `CC`'s upper bound is `[X] => Any`, but