Merge pull request #9758 from dotty-staging/scalajs-1.2.0

Upgrade to Scala.js 1.2.0.

Author: sjrd

compiler/src/dotty/tools/backend/sjs/JSCodeGen.scala

@@ -69,6 +69,7 @@ class JSCodeGen()(using genCtx: Context) {
   // Some state --------------------------------------------------------------
 
   private val generatedClasses = mutable.ListBuffer.empty[js.ClassDef]
+  private val generatedStaticForwarderClasses = mutable.ListBuffer.empty[(Symbol, js.ClassDef)]
 
   private val currentClassSym = new ScopedVar[Symbol]
   private val currentMethodSym = new ScopedVar[Symbol]
@@ -111,6 +112,7 @@ class JSCodeGen()(using genCtx: Context) {
       genCompilationUnit(ctx.compilationUnit)
     } finally {
       generatedClasses.clear()
+      generatedStaticForwarderClasses.clear()
     }
   }
 
@@ -179,6 +181,39 @@ class JSCodeGen()(using genCtx: Context) {
 
     for (tree <- generatedClasses)
       genIRFile(cunit, tree)
+
+    if (generatedStaticForwarderClasses.nonEmpty) {
+      /* #4148 Add generated static forwarder classes, except those that
+       * would collide with regular classes on case insensitive file systems.
+       */
+
+      /* I could not find any reference anywhere about what locale is used
+       * by case insensitive file systems to compare case-insensitively.
+       * In doubt, force the English locale, which is probably going to do
+       * the right thing in virtually all cases (especially if users stick
+       * to ASCII class names), and it has the merit of being deterministic,
+       * as opposed to using the OS' default locale.
+       * The JVM backend performs a similar test to emit a warning for
+       * conflicting top-level classes. However, it uses `toLowerCase()`
+       * without argument, which is not deterministic.
+       */
+      def caseInsensitiveNameOf(classDef: js.ClassDef): String =
+        classDef.name.name.nameString.toLowerCase(java.util.Locale.ENGLISH)
+
+      val generatedCaseInsensitiveNames =
+        generatedClasses.map(caseInsensitiveNameOf).toSet
+
+      for ((site, classDef) <- generatedStaticForwarderClasses) {
+        if (!generatedCaseInsensitiveNames.contains(caseInsensitiveNameOf(classDef))) {
+          genIRFile(cunit, classDef)
+        } else {
+          report.warning(
+              s"Not generating the static forwarders of ${classDef.name.name.nameString} " +
+              "because its name differs only in case from the name of another class or trait in this compilation unit.",
+              site.srcPos)
+        }
+      }
+    }
   }
 
   private def genIRFile(cunit: CompilationUnit, tree: ir.Trees.ClassDef): Unit = {
@@ -346,7 +381,7 @@ class JSCodeGen()(using genCtx: Context) {
                 forwarders,
                 Nil
             )(js.OptimizerHints.empty)
-            generatedClasses += forwardersClassDef
+            generatedStaticForwarderClasses += sym -> forwardersClassDef
           }
         }
         allMemberDefsExceptStaticForwarders
@@ -523,14 +558,33 @@ class JSCodeGen()(using genCtx: Context) {
    * `def hashCode(): Int` and a `static def hashCode(Int): Int`. The JVM
    * back-end considers them as colliding because they have the same name,
    * but we must not.
+   *
+   * By default, we only emit forwarders for top-level objects, like the JVM
+   * back-end. However, if requested via a compiler option, we enable them
+   * for all static objects. This is important so we can implement static
+   * methods of nested static classes of JDK APIs (see scala-js/#3950).
    */
 
   /** Is the given Scala class, interface or module class a candidate for
    *  static forwarders?
+   *
+   *  - the flag `-XnoForwarders` is not set to true, and
+   *  - the symbol is static, and
+   *  - either of both of the following is true:
+   *    - the flag `-scalajsGenStaticForwardersForNonTopLevelObjects` is set to true, or
+   *    - the symbol was originally at the package level
+   *
+   *  Other than the Scala.js-specific flag, and the fact that we also consider
+   *  interfaces, this performs the same tests as the JVM back-end.
    */
   def isCandidateForForwarders(sym: Symbol): Boolean = {
-    // it must be a top level class
-    sym.isStatic
+    !ctx.settings.XnoForwarders.value && sym.isStatic && {
+      ctx.settings.scalajsGenStaticForwardersForNonTopLevelObjects.value || {
+        atPhase(flattenPhase) {
+          toDenot(sym).owner.is(PackageClass)
+        }
+      }
+    }
   }
 
   /** Gen the static forwarders to the members of a class or interface for

compiler/src/dotty/tools/dotc/config/ScalaSettings.scala

@@ -65,6 +65,9 @@ class ScalaSettings extends Settings.SettingGroup {
   val pluginsDir: Setting[String]         = StringSetting       ("-Xpluginsdir", "path", "Path to search for plugin archives.", Defaults.scalaPluginPath)
   val pluginOptions: Setting[List[String]]      = MultiStringSetting  ("-P", "plugin:opt", "Pass an option to a plugin, e.g. -P:<plugin>:<opt>")
 
+  /** Scala.js-related settings */
+  val scalajsGenStaticForwardersForNonTopLevelObjects: Setting[Boolean] = BooleanSetting("-scalajs-genStaticForwardersForNonTopLevelObjects", "Generate static forwarders even for non-top-level objects (Scala.js only)")
+
   /** -X "Advanced" settings
    */
   val Xhelp: Setting[Boolean] = BooleanSetting("-X", "Print a synopsis of advanced options.")

project/Build.scala

@@ -1004,6 +1004,8 @@ object Build {
         )
       }.taskValue,
 
+      scalacOptions in Test += "-scalajs-genStaticForwardersForNonTopLevelObjects",
+
       scalaJSLinkerConfig ~= { _.withSemantics(build.TestSuiteLinkerOptions.semantics _) },
       scalaJSModuleInitializers in Test ++= build.TestSuiteLinkerOptions.moduleInitializers,
 
@@ -1023,29 +1025,15 @@ object Build {
           (dir / "shared/src/test/scala" ** (("*.scala": FileFilter)
             -- "ReflectiveCallTest.scala" // uses many forms of structural calls that are not allowed in Scala 3 anymore
             -- "EnumerationTest.scala" // scala.Enumeration support for Scala.js is not implemented in dotc (yet)
-            -- "SymbolTest.scala" // uses the old literal symbol syntax, pending update upstream
-
-            // all the following depend on HashSetTest and LinkedHashSetTest ...
-            -- "CollectionsOnCheckedCollectionTest.scala"
-            -- "CollectionsOnCheckedListTest.scala"
-            -- "CollectionsOnCheckedSetTest.scala"
-            -- "CollectionsOnSetsTest.scala"
-            -- "CollectionsOnSynchronizedCollectionTest.scala"
-            -- "CollectionsOnSynchronizedListTest.scala"
-            -- "CollectionsOnSynchronizedSetTest.scala"
-
-            // ... which do not compile because of an abstract method shadowing a concrete method, pending update upstream
-            -- "HashSetTest.scala"
-            -- "LinkedHashSetTest.scala"
             )).get
 
           ++ (dir / "shared/src/test/require-sam" ** "*.scala").get
           ++ (dir / "shared/src/test/require-jdk8" ** "*.scala").get
           ++ (dir / "shared/src/test/require-jdk7" ** "*.scala").get
 
           ++ (dir / "js/src/test/scala/org/scalajs/testsuite/compiler" ** (("*.scala": FileFilter)
-            -- "InteroperabilityTest.scala" // various compile errors, pending update upstream
-            -- "OptimizerTest.scala" // compile errors: false + string and () + string, pending update upstream
+            -- "InteroperabilityTest.scala" // compiler crash, related to value classes in JS interop
+            -- "OptimizerTest.scala" // non-native JS classes
             -- "ReflectionTest.scala" // tests fail (wrong load spec for JS globals)
             -- "RegressionJSTest.scala" // non-native JS classes
             -- "RuntimeTypesTest.scala" // compile errors: no ClassTag for Null and Nothing
@@ -1081,7 +1069,7 @@ object Build {
             )).get
 
           ++ (dir / "js/src/test/scala/org/scalajs/testsuite/library" ** (("*.scala": FileFilter)
-            -- "BigIntTest.scala" // Ambiguous reference because of new non-shadowing rule in Scala 3, pending update upstream
+            -- "BigIntTest.scala" // non-native JS classes
             -- "ObjectTest.scala" // compile errors caused by #9588
             -- "StackTraceTest.scala" // would require `npm install source-map-support`
             -- "UnionTypeTest.scala" // requires a Scala 2 macro

project/plugins.sbt

@@ -2,7 +2,7 @@
 //
 // e.g. addSbtPlugin("com.github.mpeltonen" % "sbt-idea" % "1.1.0")
 
-addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.1.1")
+addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.2.0")
 
 addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "3.6")