Migrate to 2.13

.github/workflows/ci.yml

@@ -14,26 +14,37 @@ jobs:
         command:
           - "ci-211"
           - "ci-212"
+          - "ci-213"
     steps:
       - uses: actions/checkout@v2
       - uses: olafurpg/setup-scala@v7
       - run: sbt ${{ matrix.command }}
-  jdk11:
-    name: JDK11 tests
+  jdk11_212:
+    name: JDK11/scala_2.12 tests
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
       - uses: olafurpg/setup-scala@v7
         with:
           java-version: [email protected]
       - run: sbt ci-212
-  windows:
-    name: Windows tests
+  jdk11_213:
+    name: JDK11/scala_2.13 tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: olafurpg/setup-scala@v7
+        with:
+          java-version: [email protected]
+      - run: sbt ci-213
+
+  windows_213:
+    name: Windows/scala_2.13 tests
     runs-on: windows-latest
     steps:
       - uses: actions/checkout@v2
       - uses: olafurpg/setup-scala@v7
-      - run: sbt ci-212-windows
+      - run: sbt ci-213-windows
         shell: bash
   checks:
     name: Scalafmt

build.sbt

@@ -2,8 +2,8 @@ import Dependencies._
 inThisBuild(
   List(
     onLoadMessage := s"Welcome to scalafix ${version.value}",
-    scalaVersion := scala212,
-    crossScalaVersions := List(scala212, scala211),
+    scalaVersion := scala213,
+    crossScalaVersions := List(scala213, scala212, scala211),
     fork := true
   )
 )
@@ -31,9 +31,9 @@ lazy val interfaces = project
       props.put("scalafixVersion", version.value)
       props.put("scalafixStableVersion", stableVersion.value)
       props.put("scalametaVersion", scalametaV)
+      props.put("scala213", scala213)
       props.put("scala212", scala212)
       props.put("scala211", scala211)
-      props.put("scala213", scala213)
       val out =
         managedResourceDirectories.in(Compile).value.head /
           "scalafix-interfaces.properties"
@@ -50,7 +50,7 @@ lazy val interfaces = project
     javaHome.in(Compile, doc) := inferJavaHome(),
     moduleName := "scalafix-interfaces",
     crossVersion := CrossVersion.disabled,
-    crossScalaVersions := List(scala212),
+    crossScalaVersions := List(scala213),
     autoScalaLibrary := false
   )
 
@@ -63,7 +63,8 @@ lazy val core = project
       scalameta,
       googleDiff,
       "com.geirsson" %% "metaconfig-typesafe-config" % metaconfigV,
-      "org.scala-lang" % "scala-reflect" % scalaVersion.value % Provided
+      "org.scala-lang" % "scala-reflect" % scalaVersion.value % Provided,
+      collectionCompat
     )
   )
   .enablePlugins(BuildInfoPlugin)
@@ -73,7 +74,10 @@ lazy val rules = project
   .settings(
     moduleName := "scalafix-rules",
     description := "Built-in Scalafix rules",
-    libraryDependencies += "org.scalameta" % "semanticdb-scalac-core" % scalametaV cross CrossVersion.full
+    libraryDependencies ++= List(
+      "org.scalameta" % "semanticdb-scalac-core" % scalametaV cross CrossVersion.full,
+      collectionCompat
+    )
   )
   .dependsOn(core)
 
@@ -131,7 +135,7 @@ lazy val testsInput = project
     scalacOptions += warnUnusedImports.value, // For RemoveUnused
     scalacOptions += "-Ywarn-unused", // For RemoveUnusedTerms
     logLevel := Level.Error, // avoid flood of compiler warnings
-    libraryDependencies += "com.twitter" %% "bijection-core" % "0.9.6",
+    libraryDependencies += bijectionCore,
     testsInputOutputSetting,
     coverageEnabled := false
   )
@@ -147,7 +151,7 @@ lazy val testsOutput = project
     ),
     testsInputOutputSetting,
     coverageEnabled := false,
-    libraryDependencies += "com.twitter" %% "bijection-core" % "0.9.6"
+    libraryDependencies += bijectionCore
   )
 
 lazy val testkit = project
@@ -256,9 +260,9 @@ lazy val docs = project
     baseDirectory.in(run) := baseDirectory.in(ThisBuild).value,
     skip in publish := true,
     moduleName := "scalafix-docs",
-    scalaVersion := scala212,
+    scalaVersion := scala213,
     mdoc := run.in(Compile).evaluated,
-    crossScalaVersions := List(scala212),
+    crossScalaVersions := List(scala213),
     libraryDependencies ++= List(
       "com.geirsson" %% "metaconfig-docs" % metaconfigV,
       "org.scalameta" % "semanticdb-scalac-core" % scalametaV cross CrossVersion.full

docs/developers/symbol-information.md

@@ -128,7 +128,6 @@ of length greater than 1.
 ```scala mdoc
 printMethodParameters(Symbol("example/Main#curried()."))
 printMethodParameters(Symbol("scala/Option#fold()."))
-printMethodParameters(Symbol("scala/collection/LinearSeqOptimized#foldLeft()."))
 ```
 
 ### Test if method is nullary
@@ -243,9 +242,7 @@ def getParentSymbols(symbol: Symbol): Set[Symbol] =
         case TypeRef(_, symbol, _) => getParentSymbols(symbol)
       }
   }
-getParentSymbols(Symbol("scala/Some#"))
 getParentSymbols(Symbol("java/lang/String#"))
-getParentSymbols(Symbol("scala/collection/immutable/List#")).take(5)
 ```
 
 ### Lookup class methods

project/Dependencies.scala

@@ -9,7 +9,7 @@ object Dependencies {
   def scala212 = "2.12.11"
   def scala213 = "2.13.2"
   def coursierV = "2.0.0-RC5-6"
-  val currentScalaVersion = scala212
+  val currentScalaVersion = scala213
 
   val jgit = "org.eclipse.jgit" % "org.eclipse.jgit" % "5.7.0.202003110725-r"
 
@@ -22,7 +22,9 @@ object Dependencies {
   def semanticdbPluginLibrary = "org.scalameta" % "semanticdb-scalac-core" % scalametaV cross CrossVersion.full
   def scalameta = "org.scalameta" %% "scalameta" % scalametaV
   def scalatest = "org.scalatest" %% "scalatest" % "3.0.8"
+  def bijectionCore = "com.twitter" %% "bijection-core" % "0.9.7"
   def scalacheck = "org.scalacheck" %% "scalacheck" % "1.14.3"
+  def collectionCompat = "org.scala-lang.modules" %% "scala-collection-compat" % "2.1.6"
 
   def testsDeps = List(
     // integration property tests

project/ScalafixBuild.scala

@@ -28,13 +28,13 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
     lazy val noPublish = Seq(
       skip in publish := true
     ) ++ noMima
-    lazy val supportedScalaVersions = List(scala211, scala212)
+    lazy val supportedScalaVersions = List(scala213, scala211, scala212)
     lazy val isFullCrossVersion = Seq(
       crossVersion := CrossVersion.full
     )
     lazy val isScala213 = Def.setting { scalaVersion.value.startsWith("2.13") }
     lazy val warnUnusedImports = Def.setting {
-      if (isScala213.value) "-Ywarn-unused:imports"
+      if (isScala213.value) "-Wunused:imports"
       else "-Ywarn-unused-import"
     }
     lazy val scaladocOptions = Seq(
@@ -187,22 +187,22 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
     commands += Command.command("ci-213") { s =>
       s"++$scala213" ::
         "unit/test" ::
+        "docs/run" ::
+        "interfaces/doc" ::
         s
     },
     commands += Command.command("ci-212") { s =>
       s"++$scala212" ::
         "unit/test" ::
-        "docs/run" ::
-        "interfaces/doc" ::
         s
     },
     commands += Command.command("ci-211") { s =>
       s"++$scala211" ::
         "unit/test" ::
         s
     },
-    commands += Command.command("ci-212-windows") { s =>
-      s"++$scala212" ::
+    commands += Command.command("ci-213-windows") { s =>
+      s"++$scala213" ::
         s"unit/testOnly -- -l scalafix.internal.tests.utils.SkipWindows" ::
         s
     },

scalafix-cli/src/main/scala/scalafix/internal/interfaces/ScalafixArgumentsImpl.scala

@@ -9,7 +9,7 @@ import java.util
 import java.util.Optional
 import metaconfig.Conf
 import metaconfig.Configured
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 import scala.meta.io.AbsolutePath
 import scala.meta.io.Classpath
 import scala.util.control.NoStackTrace

scalafix-cli/src/main/scala/scalafix/internal/jgit/JGitDiff.scala

@@ -23,7 +23,7 @@ import org.eclipse.jgit.treewalk.FileTreeIterator
 import org.eclipse.jgit.util.io.NullOutputStream
 import org.eclipse.jgit.lib.Constants.DOT_GIT
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 import metaconfig.{ConfError, Configured}
 

scalafix-cli/src/main/scala/scalafix/internal/v1/Args.scala

@@ -19,7 +19,6 @@ import metaconfig.internal.ConfGet
 import metaconfig.typesafeconfig.typesafeConfigMetaconfigParser
 import pprint.TPrint
 import scala.annotation.StaticAnnotation
-import scala.language.higherKinds
 import scala.meta.internal.io.PathIO
 import scala.meta.internal.symtab.SymbolTable
 import scala.meta.io.AbsolutePath

scalafix-cli/src/main/scala/scalafix/internal/v1/CompletionsOps.scala

@@ -14,7 +14,7 @@ object CompletionsOps {
     if (setting.isHidden) Nil
     else setting.name :: setting.alternativeNames.filter(_.length == 1)
 
-  private def toZshOption(setting: Setting): scala.Seq[String] = {
+  private def toZshOption(setting: Setting): scala.collection.Seq[String] = {
     if (setting.isHidden) Nil
     else {
       // See https://github.com/zsh-users/zsh-completions/blob/master/zsh-completions-howto.org#writing-completion-functions-using-_arguments

scalafix-cli/src/main/scala/scalafix/internal/v1/MainOps.scala

@@ -19,12 +19,10 @@ import metaconfig.generic.Settings
 import metaconfig.internal.Case
 import org.typelevel.paiges.{Doc => D}
 import scala.annotation.tailrec
-import scala.collection.mutable.ArrayBuffer
 import scala.collection.mutable.ListBuffer
 import scala.meta.Tree
 import scala.meta.inputs.Input
 import scala.meta.internal.semanticdb.TextDocument
-import scala.meta.internal.tokenizers.PlatformTokenizerCache
 import scala.meta.io.AbsolutePath
 import scala.meta.parsers.ParseException
 import scala.util.control.NoStackTrace
@@ -81,7 +79,7 @@ object MainOps {
   def files(args: ValidatedArgs): collection.Seq[AbsolutePath] =
     args.args.ls match {
       case Ls.Find =>
-        val buf = ArrayBuffer.empty[AbsolutePath]
+        val buf = Vector.newBuilder[AbsolutePath]
         val visitor = new SimpleFileVisitor[Path] {
           override def visitFile(
               file: Path,
@@ -273,7 +271,6 @@ object MainOps {
 
   def handleFile(args: ValidatedArgs, file: AbsolutePath): ExitStatus = {
     try {
-      PlatformTokenizerCache.megaCache.clear()
       unsafeHandleFile(args, file)
     } catch {
       case e: ParseException =>

scalafix-core/src/main/scala-2.11/scalafix/util/Compat.scala

@@ -5,4 +5,5 @@ import scala.collection.immutable.IndexedSeq
 object Compat {
   type View[T] = collection.SeqView[T, IndexedSeq[T]]
   type SeqView[T] = collection.SeqView[T, IndexedSeq[T]]
+
 }

scalafix-core/src/main/scala-2.12/scalafix/util/Compat.scala

@@ -5,4 +5,5 @@ import scala.collection.immutable.IndexedSeq
 object Compat {
   type View[T] = collection.SeqView[T, IndexedSeq[T]]
   type SeqView[T] = collection.Seq[T]
+
 }

scalafix-core/src/main/scala-2.13/scalafix/util/Compat.scala

@@ -3,4 +3,5 @@ package scalafix.util
 object Compat {
   type View[T] = collection.View[T]
   type SeqView[T] = collection.SeqView[T]
+
 }

scalafix-core/src/main/scala/org/langmeta/internal/ScalametaInternals.scala

@@ -1,13 +1,13 @@
 package scala.meta.internal
 
-import scala.compat.Platform.EOL
 import scala.meta._
 import scala.meta.internal.semanticdb.Scala.Descriptor
 import scala.meta.internal.semanticdb.Scala.DescriptorParser
 import scala.meta.internal.trees.Origin
 import scala.meta.internal.{semanticdb => s}
 
 object ScalametaInternals {
+  private val EOL = System.lineSeparator()
 
   def symbolOwnerAndDescriptor(symbol: String): (String, Descriptor) = {
     val (desc, owner) = DescriptorParser(symbol)

scalafix-core/src/main/scala/scalafix/internal/diff/DiffUtils.scala

@@ -1,7 +1,7 @@
 package scalafix.internal.diff
 
 import difflib.{DiffUtils => DU}
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 object DiffUtils {
   def unifiedDiff(

scalafix-core/src/main/scala/scalafix/internal/patch/EscapeHatch.scala

@@ -18,6 +18,7 @@ import scalafix.patch.Patch.internal._
 import scalafix.rule.RuleName
 import scalafix.util.TreeExtractors.Mods
 import scalafix.v0._
+import scala.collection.compat._ // used for cross-compilation.
 
 /** EscapeHatch is an algorithm to selectively disable rules. There
  * are two mechanisms to do so: anchored comments and the
@@ -171,7 +172,7 @@ object EscapeHatch {
       if (isEmpty) (true, None)
       else {
         val escapesUpToPos =
-          escapeTree.to(EscapeOffset(position)).valuesIterator.flatten
+          escapeTree.rangeTo(EscapeOffset(position)).valuesIterator.flatten
         escapesUpToPos
           .collectFirst {
             case f @ EscapeFilter(_, _, _, Some(end))
@@ -316,7 +317,7 @@ object EscapeHatch {
       if (disabling.isEmpty) (true, None)
       else {
         val disables =
-          disabling.to(EscapeOffset(position)).valuesIterator.flatten
+          disabling.rangeTo(EscapeOffset(position)).valuesIterator.flatten
         loop(disables.toList, None)
       }
     }

scalafix-core/src/main/scala/scalafix/internal/patch/ImportPatchOps.scala

@@ -161,7 +161,7 @@ object ImportPatchOps {
         .sortBy(_.ref.syntax)
         .map(is => ctx.addRight(editToken, s"\nimport ${is.syntax}"))
     val isRemovedImporter =
-      allImporters.toIterator
+      allImporters.iterator
         .filter(_.importees.forall(isRemovedImportee))
         .toSet
     def removeSpaces(tokens: Iterable[Token]): Patch = {

scalafix-core/src/main/scala/scalafix/internal/patch/LegacyPatchOps.scala

@@ -70,9 +70,9 @@ trait LegacyPatchOps extends PatchOps {
     Patch.replaceSymbols(toReplace: _*)
   @deprecated(DeprecationMessage, "0.6.0")
   final def replaceSymbols(
-      toReplace: Seq[(String, String)]
+      toReplace: scala.collection.Seq[(String, String)]
   )(implicit noop: DummyImplicit, index: SemanticdbIndex): Patch =
-    Patch.replaceSymbols(toReplace: _*)
+    Patch.replaceSymbols(toReplace.toSeq: _*)
   @deprecated(DeprecationMessage, "0.6.0")
   final def renameSymbol(fromSymbol: Symbol.Global, toName: String)(
       implicit index: SemanticdbIndex

scalafix-core/src/main/scala/scalafix/internal/patch/PatchInternals.scala

@@ -115,7 +115,7 @@ object PatchInternals {
     val patchMap = patches
       .groupBy(x => TokenOps.hash(x.tok))
       .mapValues(_.reduce(merge).newTok)
-    ctx.tokens.toIterator
+    ctx.tokens.iterator
       .map(tok => patchMap.getOrElse(TokenOps.hash(tok), tok.syntax))
       .mkString
   }

scalafix-core/src/main/scala/scalafix/internal/patch/ReplaceSymbolOps.scala

@@ -23,7 +23,7 @@ object ReplaceSymbolOps {
   )(implicit ctx: RuleCtx, index: SemanticdbIndex): Patch = {
     if (moveSymbols.isEmpty) return Patch.empty
     val moves: Map[String, Symbol.Global] =
-      moveSymbols.toIterator.flatMap {
+      moveSymbols.iterator.flatMap {
         case ReplaceSymbol(
             term @ Symbol.Global(_, Signature.Method(_, _)),
             to
@@ -67,7 +67,7 @@ object ReplaceSymbolOps {
     }
     object Move {
       def unapply(name: Name): Option[Symbol.Global] = {
-        val result = name.symbol.toIterator
+        val result = name.symbol.iterator
           .flatMap {
             case Symbol.Multi(syms) => syms
             case els => els :: Nil

scalafix-core/src/main/scala/scalafix/internal/util/FileOps.scala

@@ -19,7 +19,7 @@ object FileOps {
     } else {
       def listFilesIter(s: File): Iterable[String] = {
         val (dirs, files) = Option(s.listFiles()).toIterable
-          .flatMap(_.toIterator)
+          .flatMap(_.iterator)
           .partition(_.isDirectory)
         files.map(_.getPath) ++ dirs.flatMap(listFilesIter)
       }