Add stdlib-2_13-bootstrapped to bootstrap the 2.13 library

Author: nicolasstucki

.github/workflows/ci.yaml

@@ -134,7 +134,7 @@ jobs:
 
       - name: Cmd Tests
         run: |
-          ./project/scripts/sbt ";dist/pack; scala3-bootstrapped/compile; scala3-bootstrapped/test ;sbt-test/scripted scala2-compat/* ;stdlib-bootstrapped/test:run ;stdlib-bootstrapped-tasty-tests/test; scala3-compiler-bootstrapped/scala3CompilerCoursierTest:test"
+          ./project/scripts/sbt ";dist/pack; scala3-bootstrapped/compile; scala3-bootstrapped/test ;sbt-test/scripted scala2-compat/* ;stdlib-bootstrapped/test:run ;stdlib-2_13-bootstrapped/test:run ;stdlib-bootstrapped-tasty-tests/test; scala3-compiler-bootstrapped/scala3CompilerCoursierTest:test"
           ./project/scripts/cmdTests
           ./project/scripts/bootstrappedOnlyCmdTests
 
@@ -488,7 +488,7 @@ jobs:
 
       - name: Test
         run: |
-          ./project/scripts/sbt ";dist/pack ;scala3-bootstrapped/compile ;scala3-bootstrapped/test ;sbt-test/scripted scala2-compat/* ;stdlib-bootstrapped/test:run ;stdlib-bootstrapped-tasty-tests/test"
+          ./project/scripts/sbt ";dist/pack ;scala3-bootstrapped/compile ;scala3-bootstrapped/test ;sbt-test/scripted scala2-compat/* ;stdlib-bootstrapped/test:run ;stdlib-2_13-bootstrapped/test:run ;stdlib-bootstrapped-tasty-tests/test"
           ./project/scripts/cmdTests
           ./project/scripts/bootstrappedOnlyCmdTests
 

build.sbt

@@ -15,6 +15,7 @@ val `scala3-bench` = Build.`scala3-bench`
 val `scala3-bench-bootstrapped` = Build.`scala3-bench-bootstrapped`
 val `scala3-bench-micro` = Build.`scala3-bench-micro`
 val `stdlib-bootstrapped` = Build.`stdlib-bootstrapped`
+val `stdlib-2_13-bootstrapped` = Build.`stdlib-2_13-bootstrapped`
 val `stdlib-bootstrapped-tasty-tests` = Build.`stdlib-bootstrapped-tasty-tests`
 val `tasty-core` = Build.`tasty-core`
 val `tasty-core-bootstrapped` = Build.`tasty-core-bootstrapped`

project/Build.scala

@@ -922,15 +922,17 @@ object Build {
       javaOptions := (`scala3-compiler-bootstrapped` / javaOptions).value
     )
 
-  /** Scala library compiled by dotty using the latest published sources of the library */
+  /** Scala library compiled by dotty using the latest published sources of the 2.13 library
+   *  and the current Scala 3 library sources.
+   *
+   *  This version of the library is not binary compatible with the Scala 2 compiled library.
+   *  It compiles every file as Scala 3 sources.
+   */
   lazy val `stdlib-bootstrapped` = project.in(file("stdlib-bootstrapped")).
     withCommonSettings(Bootstrapped).
     dependsOn(dottyCompiler(Bootstrapped) % "provided; compile->runtime; test->test").
-    settings(commonBootstrappedSettings).
+    settings(commonStdlibBootstrappedSettings).
     settings(
-      moduleName := "scala-library",
-      javaOptions := (`scala3-compiler-bootstrapped` / javaOptions).value,
-      Compile/scalacOptions += "-Yerased-terms",
       Compile/scalacOptions ++= {
         Seq(
           "-sourcepath",
@@ -940,36 +942,6 @@ object Build {
           ).mkString(File.pathSeparator),
         )
       },
-      Compile / doc / scalacOptions += "-Ydocument-synthetic-types",
-      scalacOptions -= "-Xfatal-warnings",
-      ivyConfigurations += SourceDeps.hide,
-      transitiveClassifiers := Seq("sources"),
-      libraryDependencies +=
-        ("org.scala-lang" % "scala-library" % stdlibVersion(Bootstrapped) % "sourcedeps"),
-      (Compile / sourceGenerators) += Def.task {
-        val s = streams.value
-        val cacheDir = s.cacheDirectory
-        val trgDir = (Compile / sourceManaged).value / "scala-library-src"
-
-        val report = updateClassifiers.value
-        val scalaLibrarySourcesJar = report.select(
-            configuration = configurationFilter("sourcedeps"),
-            module = (_: ModuleID).name == "scala-library",
-            artifact = artifactFilter(`type` = "src")).headOption.getOrElse {
-          sys.error(s"Could not fetch scala-library sources")
-        }
-
-        FileFunction.cached(cacheDir / s"fetchScalaLibrarySrc",
-            FilesInfo.lastModified, FilesInfo.exists) { dependencies =>
-          s.log.info(s"Unpacking scala-library sources to $trgDir...")
-          if (trgDir.exists)
-            IO.delete(trgDir)
-          IO.createDirectory(trgDir)
-          IO.unzip(scalaLibrarySourcesJar, trgDir)
-
-          ((trgDir ** "*.scala") +++ (trgDir ** "*.java")).get.toSet
-        } (Set(scalaLibrarySourcesJar)).toSeq
-      }.taskValue,
       (Compile / sourceGenerators) += Def.task {
         val s = streams.value
         val cacheDir = s.cacheDirectory
@@ -1000,6 +972,56 @@ object Build {
 
         cachedFun(dottyLibSources.get.toSet).toSeq
       }.taskValue,
+    )
+
+  /** Scala 2 library compiled by dotty using the latest published sources of the library.
+   *
+   *  This version of the library is not (yet) binary compatible with the Scala 2 compiled library.
+   */
+  lazy val `stdlib-2_13-bootstrapped` = project.in(file("stdlib-2_13-bootstrapped")).
+    withCommonSettings(Bootstrapped).
+    dependsOn(dottyCompiler(Bootstrapped) % "provided; compile->runtime; test->test").
+    settings(commonStdlibBootstrappedSettings).
+    settings(
+      Compile/scalacOptions ++= {
+        Seq("-sourcepath", ((Compile/sourceManaged).value / "scala-library-src").toString)
+      },
+    )
+
+  lazy val commonStdlibBootstrappedSettings =
+    commonBootstrappedSettings ++ Seq(
+      moduleName := "scala-library",
+      javaOptions := (`scala3-compiler-bootstrapped` / javaOptions).value,
+      Compile / doc / scalacOptions += "-Ydocument-synthetic-types",
+      scalacOptions -= "-Xfatal-warnings",
+      ivyConfigurations += SourceDeps.hide,
+      transitiveClassifiers := Seq("sources"),
+      libraryDependencies +=
+        ("org.scala-lang" % "scala-library" % stdlibVersion(Bootstrapped) % "sourcedeps"),
+      (Compile / sourceGenerators) += Def.task {
+        val s = streams.value
+        val cacheDir = s.cacheDirectory
+        val trgDir = (Compile / sourceManaged).value / "scala-library-src"
+
+        val report = updateClassifiers.value
+        val scalaLibrarySourcesJar = report.select(
+            configuration = configurationFilter("sourcedeps"),
+            module = (_: ModuleID).name == "scala-library",
+            artifact = artifactFilter(`type` = "src")).headOption.getOrElse {
+          sys.error(s"Could not fetch scala-library sources")
+        }
+
+        FileFunction.cached(cacheDir / s"fetchScalaLibrarySrc",
+            FilesInfo.lastModified, FilesInfo.exists) { dependencies =>
+          s.log.info(s"Unpacking scala-library sources to $trgDir...")
+          if (trgDir.exists)
+            IO.delete(trgDir)
+          IO.createDirectory(trgDir)
+          IO.unzip(scalaLibrarySourcesJar, trgDir)
+
+          ((trgDir ** "*.scala") +++ (trgDir ** "*.java")).get.toSet
+        } (Set(scalaLibrarySourcesJar)).toSeq
+      }.taskValue,
       (Compile / sources) ~= (_.filterNot(file =>
         // sources from https://github.com/scala/scala/tree/2.13.x/src/library-aux
         file.getPath.endsWith("scala-library-src/scala/Any.scala") ||
@@ -1011,7 +1033,7 @@ object Build {
       (Test / managedClasspath) ~= {
         _.filterNot(file => file.data.getName == s"scala-library-${stdlibVersion(Bootstrapped)}.jar")
       },
-    )
+  )
 
   /** Test the tasty generated by `stdlib-bootstrapped`
    *

stdlib-2_13-bootstrapped/test/Main.scala

@@ -0,0 +1,12 @@
+package hello
+
+enum Color:
+  case Red, Green, Blue
+
+object HelloWorld:
+  def main(args: Array[String]): Unit = {
+    println("hello 2.13 library bootstrapped")
+    println(Color.Red)
+    println(Color.Green)
+    println(Color.Blue)
+  }