extract repl to be its own artifact

.github/workflows/stdlib.yaml

@@ -280,6 +280,24 @@ jobs:
       - name: Compile `scala3-library` for Scala.js
         run: ./project/scripts/sbt scala3-library-sjs/compile
 
+  repl:
+    runs-on: ubuntu-latest
+    needs: [scala3-compiler-bootstrapped]
+    steps:
+      - name: Git Checkout
+        uses: actions/checkout@v5
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v5
+        with:
+          distribution: 'temurin'
+          java-version: 17
+          cache: 'sbt'
+      - uses: sbt/setup-sbt@v1
+
+      - name: Compile REPL
+        run: ./project/scripts/sbt scala3-repl/compile
+
   scaladoc:
     runs-on: ubuntu-latest
     needs: [scala3-compiler-bootstrapped, scala3-tasty-inspector]
@@ -548,6 +566,23 @@ jobs:
         run: ./project/scripts/sbt ";sjsJUnitTests/clean ;set sjsJUnitTests/scalaJSLinkerConfig ~= switchToLatestESVersion ;set Global/enableWebAssembly := true; sjsJUnitTests/test"
   # TODO Scala.js on Windows
 
+  test-repl:
+    runs-on: ubuntu-latest
+    needs: [repl]
+    steps:
+      - name: Git Checkout
+        uses: actions/checkout@v5
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v5
+        with:
+          distribution: 'temurin'
+          java-version: 17
+          cache: 'sbt'
+      - uses: sbt/setup-sbt@v1
+      - name: Test REPL
+        run: ./project/scripts/sbt scala3-repl/test
+
   scripted-tests:
     runs-on: ubuntu-latest
     needs: [scala3-compiler-bootstrapped, tasty-core-bootstrapped, scala3-staging, scala3-tasty-inspector, scala-library-sjs, scaladoc]

build.sbt

@@ -7,6 +7,7 @@ val `scala3-compiler` = Build.`scala3-compiler`
 val `scala3-compiler-nonbootstrapped` = Build.`scala3-compiler-nonbootstrapped`
 val `scala3-compiler-bootstrapped-new` = Build.`scala3-compiler-bootstrapped-new`
 val `scala3-compiler-bootstrapped` = Build.`scala3-compiler-bootstrapped`
+val `scala3-repl` = Build.`scala3-repl`
 val `scala-library-sjs` = Build.`scala-library-sjs`
 val `scala3-library-sjs` = Build.`scala3-library-sjs`
 val `scala-library-nonbootstrapped` = Build.`scala-library-nonbootstrapped`

compiler/src/dotty/tools/dotc/quoted/Interpreter.scala

@@ -25,7 +25,7 @@ import dotty.tools.dotc.quoted.*
 import dotty.tools.dotc.typer.ImportInfo.withRootImports
 import dotty.tools.dotc.util.SrcPos
 import dotty.tools.dotc.reporting.Message
-import dotty.tools.repl.AbstractFileClassLoader
+import dotty.tools.io.AbstractFileClassLoader
 import dotty.tools.dotc.core.CyclicReference
 
 /** Tree interpreter for metaprogramming constructs */
@@ -35,7 +35,7 @@ class Interpreter(pos: SrcPos, classLoader0: ClassLoader)(using Context):
 
   val classLoader =
     if ctx.owner.topLevelClass.name.startsWith(str.REPL_SESSION_LINE) then
-        new AbstractFileClassLoader(ctx.settings.outputDir.value, classLoader0, "false")
+        new AbstractFileClassLoader(ctx.settings.outputDir.value, classLoader0)
     else classLoader0
 
   /** Local variable environment */
@@ -204,11 +204,7 @@ class Interpreter(pos: SrcPos, classLoader0: ClassLoader)(using Context):
     }
 
   private def loadReplLineClass(moduleClass: Symbol): Class[?] = {
-    val lineClassloader = new AbstractFileClassLoader(
-      ctx.settings.outputDir.value,
-      classLoader,
-      "false"
-    )
+    val lineClassloader = new AbstractFileClassLoader(ctx.settings.outputDir.value, classLoader)
     lineClassloader.loadClass(moduleClass.name.firstPart.toString)
   }
 

compiler/src/dotty/tools/dotc/transform/Splicer.scala

@@ -22,7 +22,7 @@ import dotty.tools.dotc.quoted.Interpreter
 
 import scala.util.control.NonFatal
 import dotty.tools.dotc.util.SrcPos
-import dotty.tools.repl.AbstractFileClassLoader
+import dotty.tools.io.AbstractFileClassLoader
 
 import scala.reflect.ClassTag
 

compiler/src/dotty/tools/dotc/util/ClasspathFromClassloader.scala

@@ -5,7 +5,7 @@ import scala.language.unsafeNulls
 import java.net.URLClassLoader
 import java.nio.file.Paths
 
-import dotty.tools.repl.AbstractFileClassLoader
+import dotty.tools.io.AbstractFileClassLoader
 
 object ClasspathFromClassloader {
 

compiler/src/dotty/tools/io/AbstractFileClassLoader.scala

@@ -0,0 +1,61 @@
+/*
+ * Scala (https://www.scala-lang.org)
+ *
+ * Copyright EPFL and Lightbend, Inc.
+ *
+ * Licensed under Apache License 2.0
+ * (http://www.apache.org/licenses/LICENSE-2.0).
+ *
+ * See the NOTICE file distributed with this work for
+ * additional information regarding copyright ownership.
+ */
+
+package dotty.tools
+package io
+
+import scala.language.unsafeNulls
+
+import dotty.tools.io.AbstractFile
+
+import java.net.{URL, URLConnection, URLStreamHandler}
+import java.util.Collections
+
+class AbstractFileClassLoader(val root: AbstractFile, parent: ClassLoader) extends ClassLoader(parent):
+  private def findAbstractFile(name: String) = root.lookupPath(name.split('/').toIndexedSeq, directory = false)
+
+  // on JDK 20 the URL constructor we're using is deprecated,
+  // but the recommended replacement, URL.of, doesn't exist on JDK 8
+  @annotation.nowarn("cat=deprecation")
+  override protected def findResource(name: String): URL | Null =
+    findAbstractFile(name) match
+      case null => null
+      case file => new URL(null, s"memory:${file.path}", new URLStreamHandler {
+        override def openConnection(url: URL): URLConnection = new URLConnection(url) {
+          override def connect() = ()
+          override def getInputStream = file.input
+        }
+      })
+  override protected def findResources(name: String): java.util.Enumeration[URL] =
+    findResource(name) match
+      case null => Collections.enumeration(Collections.emptyList[URL])  //Collections.emptyEnumeration[URL]
+      case url  => Collections.enumeration(Collections.singleton(url))
+
+  override def findClass(name: String): Class[?] = {
+    var file: AbstractFile | Null = root
+    val pathParts = name.split("[./]").toList
+    for (dirPart <- pathParts.init) {
+      file = file.lookupName(dirPart, true)
+      if (file == null) {
+        throw new ClassNotFoundException(name)
+      }
+    }
+    file = file.lookupName(pathParts.last+".class", false)
+    if (file == null) {
+      throw new ClassNotFoundException(name)
+    }
+    val bytes = file.toByteArray
+    defineClass(name, bytes, 0, bytes.length)
+  }
+
+  override def loadClass(name: String): Class[?] = try findClass(name) catch case _: ClassNotFoundException => super.loadClass(name)
+end AbstractFileClassLoader

compiler/test/dotty/Properties.scala

@@ -60,6 +60,9 @@ object Properties {
   /** dotty-compiler jar */
   def dottyCompiler: String = sys.props("dotty.tests.classes.dottyCompiler")
 
+  /** dotty-repl jar */
+  def dottyRepl: String = sys.props("dotty.tests.classes.dottyRepl")
+
   /** dotty-staging jar */
   def dottyStaging: String = sys.props("dotty.tests.classes.dottyStaging")
 

compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala

@@ -156,22 +156,17 @@ class BootstrappedOnlyCompilationTests {
 
   @Test def picklingWithCompiler: Unit = {
     implicit val testGroup: TestGroup = TestGroup("testPicklingWithCompiler")
-    // Exclude this file from the test as it contains some changes that require scala 2.13.17
-    // This filter can be dropped once we drop the dependency to Scala 2 (in 3.8.0)
-    val rlibscala3 = FileFilter.exclude(List("ScalaRunTime.scala"))
-
     aggregateTests(
       compileDir("compiler/src/dotty/tools", picklingWithCompilerOptions, recursive = false),
       compileDir("compiler/src/dotty/tools/dotc", picklingWithCompilerOptions, recursive = false),
       compileDir("library/src/scala/runtime/function", picklingWithCompilerOptions),
-      compileFilesInDir("library/src/scala/runtime", picklingWithCompilerOptions, rlibscala3),
+      compileFilesInDir("library/src/scala/runtime", picklingWithCompilerOptions),
       compileFilesInDir("compiler/src/dotty/tools/backend/jvm", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/ast", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/core", picklingWithCompilerOptions, recursive = false),
       compileDir("compiler/src/dotty/tools/dotc/config", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/parsing", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/printing", picklingWithCompilerOptions),
-      compileDir("compiler/src/dotty/tools/repl", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/rewrites", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/transform", picklingWithCompilerOptions),
       compileDir("compiler/src/dotty/tools/dotc/typer", picklingWithCompilerOptions),

compiler/test/dotty/tools/vulpix/TestConfiguration.scala

@@ -34,8 +34,6 @@ object TestConfiguration {
   val withCompilerClasspath = mkClasspath(List(
     Properties.scalaLibrary,
     Properties.scalaAsm,
-    Properties.jlineTerminal,
-    Properties.jlineReader,
     Properties.compilerInterface,
     Properties.dottyInterfaces,
     Properties.tastyCore,
@@ -54,6 +52,16 @@ object TestConfiguration {
     Properties.scalaJSLibrary,
   ))
 
+  lazy val replClassPath =
+    withCompilerClasspath + File.pathSeparator + mkClasspath(List(
+      Properties.dottyRepl,
+      Properties.jlineTerminal,
+      Properties.jlineReader,
+  ))
+
+  lazy val replWithStagingClasspath = 
+    replClassPath + File.pathSeparator + mkClasspath(List(Properties.dottyStaging))
+
   def mkClasspath(classpaths: List[String]): String =
     classpaths.map({ p =>
       val file = new java.io.File(p)
@@ -71,6 +79,8 @@ object TestConfiguration {
   val unindentOptions = TestFlags(basicClasspath, Array("-no-indent") ++ checkOptions ++ noCheckOptions ++ yCheckOptions)
   val withCompilerOptions =
     defaultOptions.withClasspath(withCompilerClasspath).withRunClasspath(withCompilerClasspath)
+  lazy val withReplOptions =
+    defaultOptions.withRunClasspath(replClassPath)
   lazy val withStagingOptions =
     defaultOptions.withClasspath(withStagingClasspath).withRunClasspath(withStagingClasspath)
   lazy val withTastyInspectorOptions =