Fix #2681: Module Splitting Support

Jenkinsfile

@@ -118,16 +118,32 @@ def Tasks = [
         helloworld$v/run \
         helloworld$v/clean &&
     sbtretry ++$scala \
-        'set artifactPath in (helloworld.v$v, Compile, fastOptJS) := (crossTarget in helloworld.v$v).value / "helloworld-fastopt.mjs"' \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        helloworld$v/run \
+        helloworld$v/clean &&
+    sbtretry ++$scala \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
         'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
         helloworld$v/run &&
     sbtretry ++$scala \
-        'set artifactPath in (helloworld.v$v, Compile, fullOptJS) := (crossTarget in helloworld.v$v).value / "helloworld-opt.mjs"' \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
+        helloworld$v/run &&
+    sbtretry ++$scala \
+        'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
         'set scalaJSLinkerConfig in helloworld.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
         'set scalaJSStage in Global := FullOptStage' \
         helloworld$v/run \
         helloworld$v/clean &&
     sbtretry ++$scala testingExample$v/testHtmlJSDom &&
+    sbtretry ++$scala \
+        'set scalaJSLinkerConfig in testingExample.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
+        'set scalaJSLinkerConfig in testingExample.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        'set scalaJSLinkerConfig in testingExample.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
+        testingExample$v/testHtml \
+        testingExample$v/clean &&
     sbtretry 'set scalaJSStage in Global := FullOptStage' \
         ++$scala testingExample$v/testHtmlJSDom \
         testingExample$v/clean &&
@@ -136,7 +152,14 @@ def Tasks = [
     sbtretry ++$scala testSuiteEx$v/test &&
     sbtretry 'set scalaJSStage in Global := FullOptStage' \
         ++$scala testSuiteEx$v/test &&
-    sbtretry ++$scala testSuite$v/test:doc library$v/test compiler$v/test reversi$v/fastOptJS reversi$v/fullOptJS &&
+    sbtretry ++$scala testSuite$v/test:doc library$v/test compiler$v/test &&
+    sbtretry ++$scala \
+        'set scalaJSLinkerConfig in reversi.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        'set scalaJSLinkerConfig in reversi.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
+        reversi$v/fastLinkJS \
+        reversi$v/fullLinkJS \
+        reversi$v/clean &&
+    sbtretry ++$scala reversi$v/fastLinkJS reversi$v/fullLinkJS &&
     sbtretry ++$scala compiler$v/compile:doc library$v/compile:doc \
         testInterface$v/compile:doc testBridge$v/compile:doc &&
     sbtretry ++$scala headerCheck &&
@@ -154,7 +177,7 @@ def Tasks = [
     sbtretry ++$scala $testSuite$v/test $testSuite$v/testHtmlJSDom &&
     sbtretry 'set scalaJSStage in Global := FullOptStage' \
         ++$scala $testSuite$v/test \
-	$testSuite$v/testHtmlJSDom \
+        $testSuite$v/testHtmlJSDom \
         $testSuite$v/clean &&
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOptimizer(false))' \
         ++$scala $testSuite$v/test &&
@@ -185,14 +208,23 @@ def Tasks = [
         ++$scala $testSuite$v/test &&
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
         ++$scala $testSuite$v/test &&
+    sbtretry \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        ++$scala $testSuite$v/test &&
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
         'set scalaJSStage in Global := FullOptStage' \
         ++$scala $testSuite$v/test \
         $testSuite$v/clean &&
-    sbtretry 'set artifactPath in ($testSuite.v$v, Test, fastOptJS) := (crossTarget in $testSuite.v$v).value / "testsuite-fastopt.mjs"' \
+    sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
+        ++$scala $testSuite$v/test &&
+    sbtretry \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
         'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
         ++$scala $testSuite$v/test &&
-    sbtretry 'set artifactPath in ($testSuite.v$v, Test, fullOptJS) := (crossTarget in $testSuite.v$v).value / "testsuite-opt.mjs"' \
+    sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
         'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
         'set scalaJSStage in Global := FullOptStage' \
         ++$scala $testSuite$v/test
@@ -271,17 +303,28 @@ def Tasks = [
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withESFeatures(_.withUseECMAScript2015(false)))' \
         'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
         ++$scala $testSuite$v/test &&
+    sbtretry \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withESFeatures(_.withUseECMAScript2015(false)))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
+        ++$scala $testSuite$v/test &&
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withESFeatures(_.withUseECMAScript2015(false)))' \
         'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.CommonJSModule))' \
         'set scalaJSStage in Global := FullOptStage' \
         ++$scala $testSuite$v/test \
         $testSuite$v/clean &&
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withESFeatures(_.withUseECMAScript2015(false)))' \
-        'set artifactPath in ($testSuite.v$v, Test, fastOptJS) := (crossTarget in $testSuite.v$v).value / "testsuite-fastopt.mjs"' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
+        ++$scala $testSuite$v/test &&
+    sbtretry \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withESFeatures(_.withUseECMAScript2015(false)))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleSplitStyle(ModuleSplitStyle.SmallestModules))' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
         'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
         ++$scala $testSuite$v/test &&
     sbtretry 'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withESFeatures(_.withUseECMAScript2015(false)))' \
-        'set artifactPath in ($testSuite.v$v, Test, fullOptJS) := (crossTarget in $testSuite.v$v).value / "testsuite-opt.mjs"' \
+        'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs")))' \
         'set scalaJSLinkerConfig in $testSuite.v$v ~= (_.withModuleKind(ModuleKind.ESModule))' \
         'set scalaJSStage in Global := FullOptStage' \
         ++$scala $testSuite$v/test

ci/checksizes.sh

@@ -20,8 +20,8 @@ case $FULLVER in
     ;;
 esac
 
-REVERSI_PREOPT="$BASEDIR/examples/reversi/.$VER/target/scala-$VER/reversi-fastopt.js"
-REVERSI_OPT="$BASEDIR/examples/reversi/.$VER/target/scala-$VER/reversi-opt.js"
+REVERSI_PREOPT="$BASEDIR/examples/reversi/.$VER/target/scala-$VER/reversi-dev/main.js"
+REVERSI_OPT="$BASEDIR/examples/reversi/.$VER/target/scala-$VER/reversi-prod/main.js"
 
 REVERSI_PREOPT_SIZE=$(stat '-c%s' "$REVERSI_PREOPT")
 REVERSI_OPT_SIZE=$(stat '-c%s' "$REVERSI_OPT")

compiler/src/main/scala/org/scalajs/nscplugin/GenJSExports.scala

@@ -143,11 +143,11 @@ trait GenJSExports[G <: Global with Singleton] extends SubComponent {
 
         kind match {
           case Module =>
-            js.TopLevelModuleExportDef(info.jsName)
+            js.TopLevelModuleExportDef(info.moduleID, info.jsName)
 
           case JSClass =>
             assert(isNonNativeJSClass(classSym), "found export on non-JS class")
-            js.TopLevelJSClassExportDef(info.jsName)
+            js.TopLevelJSClassExportDef(info.moduleID, info.jsName)
 
           case Constructor | Method =>
             val exported = tups.map(t => ExportedSymbol(t._2))
@@ -156,14 +156,14 @@ trait GenJSExports[G <: Global with Singleton] extends SubComponent {
               genExportMethod(exported, JSName.Literal(info.jsName), static = true)
             }
 
-            js.TopLevelMethodExportDef(methodDef)
+            js.TopLevelMethodExportDef(info.moduleID, methodDef)
 
           case Property =>
             throw new AssertionError("found top-level exported property")
 
           case Field =>
             val sym = checkSingleField(tups)
-            js.TopLevelFieldExportDef(info.jsName, encodeFieldSym(sym))
+            js.TopLevelFieldExportDef(info.moduleID, info.jsName, encodeFieldSym(sym))
         }
       }).toList
     }

compiler/src/main/scala/org/scalajs/nscplugin/JSGlobalAddons.scala

@@ -110,8 +110,8 @@ trait JSGlobalAddons extends JSDefinitions
     /* Not final because it causes the follwing compile warning:
      * "The outer reference in this type test cannot be checked at run time."
      */
-    case class TopLevelExportInfo(jsName: String)(val pos: Position)
-        extends ExportInfo
+    case class TopLevelExportInfo(moduleID: String, jsName: String)(
+        val pos: Position) extends ExportInfo
     case class StaticExportInfo(jsName: String)(val pos: Position)
         extends ExportInfo
 

compiler/src/main/scala/org/scalajs/nscplugin/PrepJSExports.scala

@@ -16,6 +16,7 @@ import scala.collection.mutable
 
 import scala.tools.nsc.Global
 
+import org.scalajs.ir.Names.DefaultModuleID
 import org.scalajs.ir.Trees.TopLevelExportDef.isValidTopLevelExportName
 
 /**
@@ -41,7 +42,7 @@ trait PrepJSExports[G <: Global with Singleton] { this: PrepJSInterop[G] =>
     case object Normal extends ExportDestination
 
     /** Export at the top-level. */
-    case object TopLevel extends ExportDestination
+    case class TopLevel(moduleID: String) extends ExportDestination
 
     /** Export as a static member of the companion class. */
     case object Static extends ExportDestination
@@ -142,8 +143,8 @@ trait PrepJSExports[G <: Global with Singleton] { this: PrepJSInterop[G] =>
   private def registerStaticAndTopLevelExports(sym: Symbol,
       exports: List[ExportInfo]): Unit = {
     val topLevel = exports.collect {
-      case info @ ExportInfo(jsName, ExportDestination.TopLevel) =>
-        jsInterop.TopLevelExportInfo(jsName)(info.pos)
+      case info @ ExportInfo(jsName, ExportDestination.TopLevel(moduleID)) =>
+        jsInterop.TopLevelExportInfo(moduleID, jsName)(info.pos)
     }
 
     if (topLevel.nonEmpty)
@@ -248,23 +249,40 @@ trait PrepJSExports[G <: Global with Singleton] { this: PrepJSInterop[G] =>
       assert(!isTopLevelExport || hasExplicitName,
           "Found a top-level export without an explicit name at " + annot.pos)
 
-      def explicitName = annot.stringArg(0).getOrElse {
-        reporter.error(annot.pos,
-            s"The argument to ${annot.symbol.name} must be a literal string")
-        "dummy"
-      }
-
       val name = {
-        if (hasExplicitName) explicitName
-        else if (sym.isConstructor) decodedFullName(sym.owner)
-        else if (sym.isClass) decodedFullName(sym)
-        else sym.unexpandedName.decoded.stripSuffix("_=")
+        if (hasExplicitName) {
+          annot.stringArg(0).getOrElse {
+            reporter.error(annot.args(0).pos,
+                s"The argument to ${annot.symbol.name} must be a literal string")
+            "dummy"
+          }
+        } else if (sym.isConstructor) {
+          decodedFullName(sym.owner)
+        } else if (sym.isClass) {
+          decodedFullName(sym)
+        } else {
+          sym.unexpandedName.decoded.stripSuffix("_=")
+        }
       }
 
       val destination = {
-        if (isTopLevelExport) ExportDestination.TopLevel
-        else if (isStaticExport) ExportDestination.Static
-        else ExportDestination.Normal
+        if (isTopLevelExport) {
+          val moduleID = if (annot.args.size == 1) {
+            DefaultModuleID
+          } else {
+            annot.stringArg(1).getOrElse {
+              reporter.error(annot.args(1).pos,
+                  "moduleID must be a literal string")
+              DefaultModuleID
+            }
+          }
+
+          ExportDestination.TopLevel(moduleID)
+        } else if (isStaticExport) {
+          ExportDestination.Static
+        } else {
+          ExportDestination.Normal
+        }
       }
 
       // Enforce proper setter signature
@@ -304,7 +322,7 @@ trait PrepJSExports[G <: Global with Singleton] { this: PrepJSInterop[G] =>
                   "name apply.")
             }
 
-          case ExportDestination.TopLevel =>
+          case _: ExportDestination.TopLevel =>
             throw new AssertionError(
                 "Found a top-level export without an explicit name at " +
                 annot.pos)
@@ -341,7 +359,7 @@ trait PrepJSExports[G <: Global with Singleton] { this: PrepJSInterop[G] =>
                 "Use @JSExportTopLevel instead.")
           }
 
-        case ExportDestination.TopLevel =>
+        case _: ExportDestination.TopLevel =>
           if (sym.isLazy) {
             reporter.error(annot.pos,
                 "You may not export a lazy val to the top level")

compiler/src/test/scala/org/scalajs/nscplugin/test/JSExportTest.scala

@@ -944,7 +944,31 @@ class JSExportTest extends DirectTest with TestHelpers {
     """
       |newSource1.scala:9: error: The argument to JSExport must be a literal string
       |      @JSExport(A.a)
-      |       ^
+      |                  ^
+    """
+
+  }
+
+  @Test
+  def noNonLiteralModuleID: Unit = {
+
+    """
+    object A {
+      val a = "Hello"
+      final val b = "World"
+    }
+
+    object B {
+      @JSExportTopLevel("foo", A.a)
+      def foo() = 1
+      @JSExportTopLevel("foo", A.b)
+      def bar() = 1
+    }
+    """ hasErrors
+    """
+      |newSource1.scala:9: error: moduleID must be a literal string
+      |      @JSExportTopLevel("foo", A.a)
+      |                                 ^
     """
 
   }

ir/src/main/scala/org/scalajs/ir/Names.scala

@@ -518,6 +518,9 @@ object Names {
   final val ClassInitializerName: MethodName =
     MethodName(ClassInitializerSimpleName, Nil, VoidRef)
 
+  /** ModuleID of the default module */
+  final val DefaultModuleID: String = "main"
+
   // ---------------------------------------------------
   // ----- Private helpers for validation of names -----
   // ---------------------------------------------------

ir/src/main/scala/org/scalajs/ir/Printers.scala

@@ -978,27 +978,30 @@ object Printers {
     }
 
     def print(topLevelExportDef: TopLevelExportDef): Unit = {
+      print("export top[moduleID=\"")
+      printEscapeJS(topLevelExportDef.moduleID, out)
+      print("\"] ")
+
       topLevelExportDef match {
-        case TopLevelJSClassExportDef(exportName) =>
-          print("export top class \"")
+        case TopLevelJSClassExportDef(_, exportName) =>
+          print("class \"")
           printEscapeJS(exportName, out)
-          print('\"')
+          print("\"")
 
-        case TopLevelModuleExportDef(exportName) =>
-          print("export top module \"")
+        case TopLevelModuleExportDef(_, exportName) =>
+          print("module \"")
           printEscapeJS(exportName, out)
-          print('\"')
+          print("\"")
 
-        case TopLevelMethodExportDef(methodDef) =>
-          print("export top ")
+        case TopLevelMethodExportDef(_, methodDef) =>
           print(methodDef)
 
-        case TopLevelFieldExportDef(exportName, field) =>
-          print("export top static field ")
+        case TopLevelFieldExportDef(_, exportName, field) =>
+          print("static field ")
           print(field)
           print(" as \"")
           printEscapeJS(exportName, out)
-          print('\"')
+          print("\"")
       }
     }
 

ir/src/main/scala/org/scalajs/ir/ScalaJSVersions.scala

@@ -17,8 +17,8 @@ import java.util.concurrent.ConcurrentHashMap
 import scala.util.matching.Regex
 
 object ScalaJSVersions extends VersionChecks(
-    current = "1.2.1-SNAPSHOT",
-    binaryEmitted = "1.2"
+    current = "1.3.0-SNAPSHOT",
+    binaryEmitted = "1.3-SNAPSHOT"
 )
 
 /** Helper class to allow for testing of logic. */