Restore testing in the CI and fix scala3-staging build

.github/workflows/stdlib.yaml

@@ -221,6 +221,8 @@ jobs:
       - uses: sbt/setup-sbt@v1
       - name: Compile `scala3-staging`
         run: ./project/scripts/sbt scala3-staging-new/compile
+      - name: Test `scala3-staging`
+        run: ./project/scripts/sbt scala3-staging-new/test
 
   scala3-tasty-inspector:
     runs-on: ubuntu-latest

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

@@ -9,6 +9,13 @@ import dotty.tools.io.AbstractFileClassLoader
 
 object ClasspathFromClassloader {
 
+  // Class name of the REPL classloader.
+  // We can't import AbstractFileClassLoader directly because the REPL module
+  // depends on compiler, not vice-versa. The class name comparison is required
+  // anyway because the REPL classloader class is normally loaded with a different
+  // classloader (see the comment below at the usage site).
+  private final val ReplAbstractFileClassLoaderName = "dotty.tools.repl.AbstractFileClassLoader"
+
   /** Attempt to recreate a classpath from a classloader.
    *
    *  BEWARE: with exotic enough classloaders, this may not work at all or do
@@ -29,7 +36,8 @@ object ClasspathFromClassloader {
             classpathBuff ++=
               cl.getURLs.iterator.map(url => Paths.get(url.toURI).toAbsolutePath.toString)
           case _ =>
-            if cl.getClass.getName == classOf[AbstractFileClassLoader].getName then
+            if cl.getClass.getName == ReplAbstractFileClassLoaderName ||
+               cl.getClass.getName == classOf[AbstractFileClassLoader].getName then
               // HACK: We can't just collect the classpath from arbitrary parent
               // classloaders since the current classloader might intentionally
               // filter loading classes from its parent (for example

compiler/test/dotty/Properties.scala

@@ -52,31 +52,31 @@ object Properties {
   val testsSafeMode: Boolean = sys.props.isDefinedAt("dotty.tests.safemode")
 
   /** Extra directory containing sources for the compiler */
-  def dottyCompilerManagedSources: Path = Paths.get(sys.props("dotty.tests.dottyCompilerManagedSources"))
+  def dottyCompilerManagedSources: Path = Paths.get(requireNonEmptyProperty("dotty.tests.dottyCompilerManagedSources"))
 
   /** dotty-interfaces jar */
-  def dottyInterfaces: String = sys.props("dotty.tests.classes.dottyInterfaces")
+  def dottyInterfaces: String = requireNonEmptyProperty("dotty.tests.classes.dottyInterfaces")
 
   /** dotty-compiler jar */
-  def dottyCompiler: String = sys.props("dotty.tests.classes.dottyCompiler")
+  def dottyCompiler: String = requireNonEmptyProperty("dotty.tests.classes.dottyCompiler")
 
   /** dotty-repl jar */
-  def dottyRepl: String = sys.props("dotty.tests.classes.dottyRepl")
+  def dottyRepl: String = requireNonEmptyProperty("dotty.tests.classes.dottyRepl")
 
   /** dotty-staging jar */
-  def dottyStaging: String = sys.props("dotty.tests.classes.dottyStaging")
+  def dottyStaging: String = requireNonEmptyProperty("dotty.tests.classes.dottyStaging")
 
   /** dotty-tasty-inspector jar */
-  def dottyTastyInspector: String = sys.props("dotty.tests.classes.dottyTastyInspector")
+  def dottyTastyInspector: String = requireNonEmptyProperty("dotty.tests.classes.dottyTastyInspector")
 
   /** tasty-core jar */
-  def tastyCore: String = sys.props("dotty.tests.classes.tastyCore")
+  def tastyCore: String = requireNonEmptyProperty("dotty.tests.classes.tastyCore")
 
   /** compiler-interface jar */
-  def compilerInterface: String = sys.props("dotty.tests.classes.compilerInterface")
+  def compilerInterface: String = requireNonEmptyProperty("dotty.tests.classes.compilerInterface")
 
   /** scala-library jar */
-  def scalaLibrary: String = sys.props("dotty.tests.classes.scalaLibrary")
+  def scalaLibrary: String = requireNonEmptyProperty("dotty.tests.classes.scalaLibrary")
 
   // TODO: Remove this once we migrate the test suite
   def usingScalaLibraryCCTasty: Boolean = true
@@ -85,20 +85,27 @@ object Properties {
   def usingScalaLibraryTasty: Boolean = true
 
   /** scala-asm jar */
-  def scalaAsm: String = sys.props("dotty.tests.classes.scalaAsm")
+  def scalaAsm: String = requireNonEmptyProperty("dotty.tests.classes.scalaAsm")
 
   /** jline-terminal jar */
-  def jlineTerminal: String = sys.props("dotty.tests.classes.jlineTerminal")
+  def jlineTerminal: String = requireNonEmptyProperty("dotty.tests.classes.jlineTerminal")
 
   /** jline-reader jar */
-  def jlineReader: String = sys.props("dotty.tests.classes.jlineReader")
+  def jlineReader: String = requireNonEmptyProperty("dotty.tests.classes.jlineReader")
 
   /** scalajs-javalib jar */
-  def scalaJSJavalib: String = sys.props("dotty.tests.classes.scalaJSJavalib")
+  def scalaJSJavalib: String = requireNonEmptyProperty("dotty.tests.classes.scalaJSJavalib")
 
   /** scalajs-scalalib jar */
-  def scalaJSScalalib: String = sys.props("dotty.tests.classes.scalaJSScalalib")
+  def scalaJSScalalib: String = requireNonEmptyProperty("dotty.tests.classes.scalaJSScalalib")
 
   /** scalajs-library jar */
-  def scalaJSLibrary: String = sys.props("dotty.tests.classes.scalaJSLibrary")
+  def scalaJSLibrary: String = requireNonEmptyProperty("dotty.tests.classes.scalaJSLibrary")
+
+  private def requireNonEmptyProperty(name: String): String = {
+    sys.props(name).ensuring(
+      value => value != null && value.nonEmpty,
+      s"Property $name is not set"
+    )
+  }
 }

project/Build.scala

@@ -1009,6 +1009,7 @@ object Build {
     // when compiling a project that depends on scala3-staging (see sbt-test/sbt-dotty/quoted-example-project),
     // but we always need it to be present on the JVM classpath at runtime.
     .dependsOn(`scala3-compiler-bootstrapped-new` % "provided; compile->runtime; test->test")
+    .dependsOn(`scala3-repl` % "provided; compile->runtime; test->test")
     .settings(publishSettings)
     .settings(
       name          := "scala3-staging",
@@ -1021,6 +1022,7 @@ object Build {
       // Add the source directories for the sbt-bridge (boostrapped)
       Compile / unmanagedSourceDirectories := Seq(baseDirectory.value / "src"),
       Test    / unmanagedSourceDirectories := Seq(baseDirectory.value / "test"),
+      Test    / unmanagedResourceDirectories := Seq(baseDirectory.value / "test-resources"),
       // Packaging configuration of `scala3-staging`
       Compile / packageBin / publishArtifact := true,
       Compile / packageDoc / publishArtifact := true,
@@ -1056,6 +1058,21 @@ object Build {
       scalaCompilerBridgeBinaryJar := {
         Some((`scala3-sbt-bridge-nonbootstrapped` / Compile / packageBin).value)
       },
+      Test / javaOptions ++= {
+        val externalDeps = (ThisProject / Runtime / externalDependencyClasspath).value
+        Seq(
+          s"-Ddotty.tests.classes.compilerInterface=${findArtifactPath(externalDeps, "compiler-interface")}",
+          s"-Ddotty.tests.classes.dottyCompiler=${(`scala3-compiler-bootstrapped-new` / Compile / packageBin).value}",
+          s"-Ddotty.tests.classes.dottyInterfaces=${(`scala3-interfaces` / Compile / packageBin).value}",
+          s"-Ddotty.tests.classes.dottyRepl=${(`scala3-repl` / Compile / packageBin).value}",
+          s"-Ddotty.tests.classes.dottyStaging=${(ThisProject / Compile / packageBin).value}",
+          s"-Ddotty.tests.classes.jlineReader=${findArtifactPath(externalDeps, "jline-reader")}",
+          s"-Ddotty.tests.classes.jlineTerminal=${findArtifactPath(externalDeps, "jline-terminal")}",
+          s"-Ddotty.tests.classes.scalaAsm=${findArtifactPath(externalDeps, "scala-asm")}",
+          s"-Ddotty.tests.classes.scalaLibrary=${(`scala-library-bootstrapped` / Compile / packageBin).value}",
+          s"-Ddotty.tests.classes.tastyCore=${(`tasty-core-bootstrapped-new` / Compile / packageBin).value}",
+        )
+      },
       bspEnabled := false,
     )