[sync/backports]: Synchronize with scala/scala3-lts

.github/Dockerfile

@@ -15,7 +15,8 @@ RUN apt-get update && \
                        openjdk-17-jdk-headless \
                        openjdk-21-jdk-headless && \
     (curl -fsSL https://deb.nodesource.com/setup_18.x | bash -) && \
-    apt-get install -y nodejs
+    apt-get install -y nodejs && \
+    apt-get install -y zip unzip
 
 
 # Install sbt

.github/workflows/ci.yaml

@@ -48,7 +48,7 @@ jobs:
   test_non_bootstrapped:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -100,7 +100,7 @@ jobs:
   test:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -175,7 +175,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Test
-        run: sbt ";scala3-bootstrapped/compile; scala3-bootstrapped/testCompilation"
+        run: sbt ";scala3-bootstrapped/compile; scala3-bootstrapped/testCompilation; scala3-presentation-compiler-bootstrapped/test; scala3-language-server/test"
         shell: cmd
 
       - name: build binary
@@ -230,7 +230,7 @@ jobs:
     name: MiMa
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -276,7 +276,7 @@ jobs:
   community_build_a:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -330,7 +330,7 @@ jobs:
   community_build_b:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -384,7 +384,7 @@ jobs:
   community_build_c:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -438,7 +438,7 @@ jobs:
   test_sbt:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -483,7 +483,7 @@ jobs:
   test_java8:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -539,7 +539,7 @@ jobs:
   publish_nightly:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -580,6 +580,14 @@ jobs:
           echo "This build version: $ver"
           echo "THISBUILD_VERSION=$ver" >> $GITHUB_ENV
 
+      - name: Check is version matching pattern
+        shell: bash
+        run: |
+          if ! grep -Eo "3\.[0-9]+\.[0-9]+-RC[0-9]+-bin-[0-9]{8}-[a-zA-Z0-9]{7}-NIGHTLY" <<< "${{ env.THISBUILD_VERSION }}"; then
+            echo "Version used by compiler to publish nightly release does not match expected pattern"
+            exit 1
+          fi
+
       - name: Check whether not yet published
         id: not_yet_published
         continue-on-error: true
@@ -594,7 +602,7 @@ jobs:
   nightly_documentation:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -648,7 +656,7 @@ jobs:
       contents: write  # for actions/create-release to create a release
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
       options: --cpu-shares 4096
       volumes:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
@@ -685,6 +693,16 @@ jobs:
       - name: Add SBT proxy repositories
         run: cp -vf .github/workflows/repositories /root/.sbt/ ; true
 
+      - name: Check compiler version
+        shell: bash
+        run : |
+          version=$(./project/scripts/sbt "print scala3-compiler-bootstrapped/version" | tail -n1)
+          echo "This build version: ${version}"
+          if [ "${version}" != "${{ env.RELEASE_TAG }}" ]; then
+            echo "Compiler version for this build '${version}', does not match tag: ${{ env.RELEASE_TAG }}"
+            exit 1
+          fi
+
       - name: Prepare Release
         run: |
           ./project/scripts/sbt dist/packArchive
@@ -740,7 +758,7 @@ jobs:
   open_issue_on_failure:
     runs-on: [self-hosted, Linux]
     container:
-      image: lampepfl/dotty:2023-11-07
+      image: lampepfl/dotty:2024-10-18
     needs: [nightly_documentation, test_windows_full]
     # The `failure()` expression is true iff at least one of the dependencies
     # of this job (including transitive dependencies) has failed.

community-build/src/scala/dotty/communitybuild/projects.scala

@@ -492,8 +492,8 @@ object projects:
 
   lazy val scalaCollectionCompat = SbtCommunityProject(
     project        = "scala-collection-compat",
-    sbtTestCommand = "compat30/test",
-    sbtPublishCommand = "compat30/publishLocal",
+    sbtTestCommand = "compat3/test",
+    sbtPublishCommand = "compat3/publishLocal",
   )
 
   lazy val scalaJava8Compat = SbtCommunityProject(

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -19,6 +19,7 @@ import printing.Formatting.hl
 import config.Printers
 
 import scala.annotation.internal.sharable
+import dotty.tools.dotc.util.SrcPos
 
 object desugar {
   import untpd.*
@@ -934,8 +935,8 @@ object desugar {
           paramss match
             case rightParam :: paramss1 => // `rightParam` must have a single parameter and without `given` flag
 
-              def badRightAssoc(problem: String) =
-                report.error(em"right-associative extension method $problem", mdef.srcPos)
+              def badRightAssoc(problem: String, pos: SrcPos) =
+                report.error(em"right-associative extension method $problem", pos)
                 extParamss ++ mdef.paramss
 
               rightParam match
@@ -951,11 +952,23 @@ object desugar {
                     //
                     // If you change the names of the clauses below, also change them in right-associative-extension-methods.md
                     val (leftTyParamsAndLeadingUsing, leftParamAndTrailingUsing) = extParamss.span(isUsingOrTypeParamClause)
+
+                    val names = (for ps <- mdef.paramss; p <- ps yield p.name).toSet[Name]
+
+                    val tt = new untpd.UntypedTreeTraverser:
+                      def traverse(tree: Tree)(using Context): Unit = tree match
+                        case tree: Ident if names.contains(tree.name) =>
+                          badRightAssoc(s"cannot have a forward reference to ${tree.name}", tree.srcPos)
+                        case _ => traverseChildren(tree)
+
+                    for ts <- leftParamAndTrailingUsing; t <- ts do
+                      tt.traverse(t)
+
                     leftTyParamsAndLeadingUsing ::: rightTyParams ::: rightParam :: leftParamAndTrailingUsing ::: paramss1
                   else
-                    badRightAssoc("cannot start with using clause")
+                    badRightAssoc("cannot start with using clause", mdef.srcPos)
                 case _ =>
-                  badRightAssoc("must start with a single parameter")
+                  badRightAssoc("must start with a single parameter", mdef.srcPos)
             case _ =>
               // no value parameters, so not an infix operator.
               extParamss ++ mdef.paramss

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

@@ -10,7 +10,7 @@ import java.io.IOException
 import java.util.jar.Attributes.{ Name => AttributeName }
 import java.nio.charset.StandardCharsets
 
-/** Loads `library.properties` from the jar. */
+/** Loads `compiler.properties` from the jar. */
 object Properties extends PropertiesTrait {
   protected def propCategory: String = "compiler"
   protected def pickJarBasedOn: Class[PropertiesTrait] = classOf[PropertiesTrait]

compiler/src/dotty/tools/dotc/core/Phases.scala

@@ -333,15 +333,20 @@ object Phases {
       for unit <- units do
         given unitCtx: Context = runCtx.fresh.setPhase(this.start).setCompilationUnit(unit).withRootImports
         if ctx.run.enterUnit(unit) then
-          try run
-          catch case ex: Throwable if !ctx.run.enrichedErrorMessage =>
-            println(ctx.run.enrichErrorMessage(s"unhandled exception while running $phaseName on $unit"))
-            throw ex
+          try
+            run
+            buf += unitCtx.compilationUnit
+          catch
+            case _: CompilationUnit.SuspendException => // this unit will be run again in `Run#compileSuspendedUnits`
+            case ex: Throwable if !ctx.run.enrichedErrorMessage =>
+              println(ctx.run.enrichErrorMessage(s"unhandled exception while running $phaseName on $unit"))
+              throw ex
           finally ctx.run.advanceUnit()
-          buf += unitCtx.compilationUnit
         end if
       end for
-      buf.result()
+      val res = buf.result()
+      ctx.run.nn.checkSuspendedUnits(res)
+      res
     end runOn
 
     /** Convert a compilation unit's tree to a string; can be overridden */

compiler/src/dotty/tools/dotc/core/Types.scala

@@ -140,6 +140,9 @@ object Types extends TypeUtils {
               !t.isPermanentlyInstantiated || test(t.permanentInst, theAcc)
             case t: LazyRef =>
               !t.completed || test(t.ref, theAcc)
+            case t: ParamRef =>
+              (t: Type).mightBeProvisional = false // break cycles
+              test(t.underlying, theAcc)
             case _ =>
               (if theAcc != null then theAcc else ProAcc()).foldOver(false, t)
         end if

compiler/src/dotty/tools/dotc/parsing/JavaParsers.scala

@@ -363,8 +363,8 @@ object JavaParsers {
     def annotation(): Option[Tree] = {
       def classOrId(): Tree =
         val id = qualId()
-        if in.lookaheadToken == CLASS then
-          in.nextToken()
+        if in.token == DOT && in.lookaheadToken == CLASS then
+          accept(DOT)
           accept(CLASS)
           TypeApply(
             Select(

compiler/src/dotty/tools/dotc/parsing/Parsers.scala

@@ -429,6 +429,14 @@ object Parsers {
       finally inEnum = saved
     }
 
+    private var inMatchPattern = false
+    private def withinMatchPattern[T](body: => T): T = {
+      val saved = inMatchPattern
+      inMatchPattern = true
+      try body
+      finally inMatchPattern = saved
+    }
+
     private var staged = StageKind.None
     def withinStaged[T](kind: StageKind)(op: => T): T = {
       val saved = staged
@@ -1857,7 +1865,7 @@ object Parsers {
       if isSimpleLiteral then
         SingletonTypeTree(simpleLiteral())
       else if in.token == USCORE then
-        if ctx.settings.YkindProjector.value == "underscores" then
+        if ctx.settings.YkindProjector.value == "underscores" && !inMatchPattern then
           val start = in.skipToken()
           Ident(tpnme.USCOREkw).withSpan(Span(start, in.lastOffset, start))
         else
@@ -2883,7 +2891,7 @@ object Parsers {
     def caseClause(exprOnly: Boolean = false): CaseDef = atSpan(in.offset) {
       val (pat, grd) = inSepRegion(InCase) {
         accept(CASE)
-        (pattern(), guard())
+        (withinMatchPattern(pattern()), guard())
       }
       CaseDef(pat, grd, atSpan(accept(ARROW)) {
         if exprOnly then
@@ -2907,7 +2915,7 @@ object Parsers {
             val start = in.skipToken()
             Ident(tpnme.WILDCARD).withSpan(Span(start, in.lastOffset, start))
           case _ =>
-            rejectWildcardType(infixType())
+            withinMatchPattern(rejectWildcardType(infixType()))
         }
       }
       CaseDef(pat, EmptyTree, atSpan(accept(ARROW)) {

compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala

@@ -214,6 +214,8 @@ enum ErrorMessageID(val isActive: Boolean = true) extends java.lang.Enum[ErrorMe
   case UnusedSymbolID // errorNumber: 198
   case TailrecNestedCallID //errorNumber: 199 - unused in LTS
   case FinalLocalDefID // errorNumber: 200
+  case NonNamedArgumentInJavaAnnotationID // errorNumber: 201 - unused in LTS
+  case QuotedTypeMissingID // errorNumber: 202
 
   def errorNumber = ordinal - 1
 

compiler/src/dotty/tools/dotc/reporting/MessageKind.scala

@@ -22,6 +22,7 @@ enum MessageKind:
   case Compatibility
   case PotentialIssue
   case UnusedSymbol
+  case Staging
 
   /** Human readable message that will end up being shown to the user.
    *  NOTE: This is only used in the situation where you have multiple words
@@ -39,5 +40,6 @@ enum MessageKind:
       case MatchCaseUnreachable => "Match case Unreachable"
       case PotentialIssue => "Potential Issue"
       case UnusedSymbol => "Unused Symbol"
+      case Staging => "Staging Issue"
       case kind => kind.toString
 end MessageKind