Merge branch 'main' into scaladoc-types-rendering-fixes

Author: Florian3k

.github/workflows/ci.yaml

@@ -253,7 +253,7 @@ jobs:
 
       - name: MiMa
         run: |
-          ./project/scripts/sbt ";scala3-interfaces/mimaReportBinaryIssues ;scala3-library-bootstrapped/mimaReportBinaryIssues ;scala3-library-bootstrappedJS/mimaReportBinaryIssues; tasty-core-bootstrapped/mimaReportBinaryIssues"
+          ./project/scripts/sbt ";scala3-interfaces/mimaReportBinaryIssues ;scala3-library-bootstrapped/mimaReportBinaryIssues ;scala3-library-bootstrappedJS/mimaReportBinaryIssues; tasty-core-bootstrapped/mimaReportBinaryIssues; stdlib-bootstrapped/mimaReportBinaryIssues"
 
   community_build_a:
     runs-on: [self-hosted, Linux]

.github/workflows/scaladoc.yaml

@@ -4,9 +4,11 @@ on:
   push:
     branches-ignore:
       - 'language-reference-stable'
+      - 'gh-readonly-queue/**'
   pull_request:
     branches-ignore:
       - 'language-reference-stable'
+  merge_group:
 permissions:
   contents: read
 
@@ -15,7 +17,8 @@ jobs:
     env:
       AZURE_STORAGE_SAS_TOKEN: ${{ secrets.AZURE_STORAGE_SAS_TOKEN }}
     runs-on: ubuntu-latest
-    if: "(    github.event_name == 'pull_request'
+    if: "github.event_name == 'merge_group'
+         || (    github.event_name == 'pull_request'
            && !contains(github.event.pull_request.body, '[skip ci]')
            && !contains(github.event.pull_request.body, '[skip docs]')
          )

CONTRIBUTING.md

@@ -2,4 +2,4 @@
 
 Firstly, thanks for being willing to contribute to Dotty! Head on over the
 [Scala 3 Contributing
-Guide](https://docs.scala-lang.org/scala3/guides/contribution/contribution-intro.html), which should have all the info you're looking for.
+Guide](https://dotty.epfl.ch/docs/contributing/index.html), which should have all the info you're looking for.

MAINTENANCE.md

@@ -61,28 +61,36 @@ At the end of their supervision period, the supervisor reports to the team durin
 
 The following is the list of all the principal areas of the compiler and the core team members who are responsible for their maintenance:
 
+### Compiler
 - Parser: @odersky
 - Typer: @odersky, @smarter, (@dwijnand)
 - Erasure: @smarter, @odersky
 - Enums: @bishabosha
+- Derivation & Mirrors: @bishabosha, (@dwijnand)
 - Export: @bishabosha, @odersky
 - Pattern Matching: @dwijnand, (@liufengyun), @sjrd
 - Inline: @nicolasstucki, @odersky
-- Metaprogramming (Quotes, Reflect, Staging): @nicolasstucki, @aherlihy
-- Match types: @OlivierBlanvillain, @dwijnand
-- GADT: @abgruszecki, @dwijnand
-- Scaladoc: @KacperFKorban,  @BarkingBad, @pikinier20
-- Initialization checker: @olhotak, @liufengyun, @anatoliykmetyuk
+- Metaprogramming (Quotes, Reflect, Staging): @nicolasstucki, @jchyb
+- Match types: @sjrd, @dwijnand, @Decel
+- GADT: @dwijnand, @Linyxus
+- Initialization checker: @olhotak, @liufengyun
 - Safe nulls: @noti0na1, @olhotak
+- Lazy vals: @szymon-rd, @sjrd
 - tailrec: @sjrd, @mbovel
 - JS backend: @sjrd
-- forward compat (-scala-release): @prolativ, @Kordyjan, (@nicolasstucki)
-- Benchmarks: @anatoliykmetyuk, @mbovel
-- REPL: @dwijnand, @anatoliykmetyuk, @prolativ
+- JVM backend: @sjrd
+- Java-compat: @smarter
+
+### Tooling
+- REPL: @dwijnand, @prolativ
+- Scaladoc: @Florian3k
+- SemanticDB: @tanishiking
+- Coverage: @TheElectronWill
+- Linting (especially unused warnings) / Reporting UX: @szymon-rd
+
+### Infrastructure
 - CI: @anatoliykmetyuk
 - Community Build: @anatoliykmetyuk
+- Open Community Build: @WojciechMazur
 - Vulpix: @dwijnand, @prolativ
-- JVM backend: @Kordyjan, (@sjrd)
-- Derivation & Mirrors: @bishabosha, (@dwijnand)
-- Linting (especially unused warnings) / Reporting UX: VirtusLab TBD?
-- Java-compat: @Kordyjan
+- Benchmarks: @mbovel

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

@@ -140,7 +140,7 @@ final case class SbtCommunityProject(
       case Some(ivyHome) => List(s"-Dsbt.ivy.home=$ivyHome")
       case _ => Nil
     extraSbtArgs ++ sbtProps ++ List(
-      "-sbt-version", "1.8.0",
+      "-sbt-version", "1.8.2",
       "-Dsbt.supershell=false",
       s"-Ddotty.communitybuild.dir=$communitybuildDir",
       s"--addPluginSbtFile=$sbtPluginFilePath"

compiler/src/dotty/tools/backend/jvm/BackendUtils.scala

@@ -35,6 +35,7 @@ class BackendUtils(val postProcessor: PostProcessor) {
     case "18" => asm.Opcodes.V18
     case "19" => asm.Opcodes.V19
     case "20" => asm.Opcodes.V20
+    case "21" => asm.Opcodes.V21
   }
 
   lazy val extraProc: Int = {

compiler/src/dotty/tools/dotc/CompilationUnit.scala

@@ -154,11 +154,13 @@ object CompilationUnit {
     var containsCaptureChecking = false
     var containsMacroAnnotation = false
     def traverse(tree: Tree)(using Context): Unit = {
-      if (tree.symbol.isQuote)
-        containsQuote = true
       if tree.symbol.is(Flags.Inline) then
         containsInline = true
       tree match
+        case _: tpd.Quote =>
+          containsQuote = true
+        case tree: tpd.Apply if tree.symbol == defn.QuotedTypeModule_of =>
+          containsQuote = true
         case Import(qual, selectors) =>
           tpd.languageImport(qual) match
             case Some(prefix) =>

compiler/src/dotty/tools/dotc/Compiler.scala

@@ -35,7 +35,7 @@ class Compiler {
   protected def frontendPhases: List[List[Phase]] =
     List(new Parser) ::             // Compiler frontend: scanner, parser
     List(new TyperPhase) ::         // Compiler frontend: namer, typer
-    List(new CheckUnused) ::        // Check for unused elements
+    List(new CheckUnused.PostTyper) ::  // Check for unused elements
     List(new YCheckPositions) ::    // YCheck positions
     List(new sbt.ExtractDependencies) :: // Sends information on classes' dependencies to sbt via callbacks
     List(new semanticdb.ExtractSemanticDB) :: // Extract info into .semanticdb files
@@ -50,6 +50,7 @@ class Compiler {
     List(new Pickler) ::            // Generate TASTY info
     List(new Inlining) ::           // Inline and execute macros
     List(new PostInlining) ::       // Add mirror support for inlined code
+    List(new CheckUnused.PostInlining) ::  // Check for unused elements
     List(new Staging) ::            // Check staging levels and heal staged types
     List(new Splicing) ::           // Replace level 1 splices with holes
     List(new PickleQuotes) ::       // Turn quoted trees into explicit run-time data structures
@@ -58,7 +59,8 @@ class Compiler {
   /** Phases dealing with the transformation from pickled trees to backend trees */
   protected def transformPhases: List[List[Phase]] =
     List(new InstrumentCoverage) ::  // Perform instrumentation for code coverage (if -coverage-out is set)
-    List(new FirstTransform,         // Some transformations to put trees into a canonical form
+    List(new CrossVersionChecks,     // Check issues related to deprecated and experimental
+         new FirstTransform,         // Some transformations to put trees into a canonical form
          new CheckReentrant,         // Internal use only: Check that compiled program has no data races involving global vars
          new ElimPackagePrefixes,    // Eliminate references to package prefixes in Select nodes
          new CookComments,           // Cook the comments: expand variables, doc, etc.
@@ -70,8 +72,7 @@ class Compiler {
          new ElimRepeated,           // Rewrite vararg parameters and arguments
          new RefChecks) ::           // Various checks mostly related to abstract members and overriding
     List(new init.Checker) ::        // Check initialization of objects
-    List(new CrossVersionChecks,     // Check issues related to deprecated and experimental
-         new ProtectedAccessors,     // Add accessors for protected members
+    List(new ProtectedAccessors,     // Add accessors for protected members
          new ExtensionMethods,       // Expand methods of value classes with extension methods
          new UncacheGivenAliases,    // Avoid caching RHS of simple parameterless given aliases
          new ElimByName,             // Map by-name parameters to functions

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

@@ -338,9 +338,9 @@ object desugar {
   def quotedPattern(tree: untpd.Tree, expectedTpt: untpd.Tree)(using Context): untpd.Tree = {
     def adaptToExpectedTpt(tree: untpd.Tree): untpd.Tree = tree match {
       // Add the expected type as an ascription
-      case _: untpd.Splice =>
+      case _: untpd.SplicePattern =>
         untpd.Typed(tree, expectedTpt).withSpan(tree.span)
-      case Typed(expr: untpd.Splice, tpt) =>
+      case Typed(expr: untpd.SplicePattern, tpt) =>
         cpy.Typed(tree)(expr, untpd.makeAndType(tpt, expectedTpt).withSpan(tpt.span))
 
       // Propagate down the expected type to the leafs of the expression
@@ -637,7 +637,10 @@ object desugar {
     //       new C[...](p1, ..., pN)(moreParams)
     val (caseClassMeths, enumScaffolding) = {
       def syntheticProperty(name: TermName, tpt: Tree, rhs: Tree) =
-        DefDef(name, Nil, tpt, rhs).withMods(synthetic)
+        val mods =
+          if ctx.settings.Yscala2Stdlib.value then synthetic | Inline
+          else synthetic
+        DefDef(name, Nil, tpt, rhs).withMods(mods)
 
       def productElemMeths =
         val caseParams = derivedVparamss.head.toArray
@@ -735,13 +738,25 @@ object desugar {
               .withMods(appMods) :: Nil
           }
         val unapplyMeth = {
+          def scala2LibCompatUnapplyRhs(unapplyParamName: Name) =
+            assert(arity <= Definitions.MaxTupleArity, "Unexpected case class with tuple larger than 22: "+ cdef.show)
+            if arity == 1 then Apply(scalaDot(nme.Option), Select(Ident(unapplyParamName), nme._1))
+            else
+              val tupleApply = Select(Ident(nme.scala), s"Tuple$arity".toTermName)
+              val members = List.tabulate(arity) { n => Select(Ident(unapplyParamName), s"_${n+1}".toTermName) }
+              Apply(scalaDot(nme.Option), Apply(tupleApply, members))
+
           val hasRepeatedParam = constrVparamss.head.exists {
             case ValDef(_, tpt, _) => isRepeated(tpt)
           }
           val methName = if (hasRepeatedParam) nme.unapplySeq else nme.unapply
           val unapplyParam = makeSyntheticParameter(tpt = classTypeRef)
-          val unapplyRHS = if (arity == 0) Literal(Constant(true)) else Ident(unapplyParam.name)
+          val unapplyRHS =
+            if (arity == 0) Literal(Constant(true))
+            else if ctx.settings.Yscala2Stdlib.value then scala2LibCompatUnapplyRhs(unapplyParam.name)
+            else Ident(unapplyParam.name)
           val unapplyResTp = if (arity == 0) Literal(Constant(true)) else TypeTree()
+
           DefDef(
             methName,
             joinParams(derivedTparams, (unapplyParam :: Nil) :: Nil),
@@ -1824,16 +1839,6 @@ object desugar {
         flatTree(pats1 map (makePatDef(tree, mods, _, rhs)))
       case ext: ExtMethods =>
         Block(List(ext), Literal(Constant(())).withSpan(ext.span))
-      case CapturingTypeTree(refs, parent) =>
-        // convert   `{refs} T`   to `T @retains refs`
-        //           `{refs}-> T` to `-> (T @retainsByName refs)`
-        def annotate(annotName: TypeName, tp: Tree) =
-          Annotated(tp, New(scalaAnnotationDot(annotName), List(refs)))
-        parent match
-          case ByNameTypeTree(restpt) =>
-            cpy.ByNameTypeTree(parent)(annotate(tpnme.retainsByName, restpt))
-          case _ =>
-            annotate(tpnme.retains, parent)
       case f: FunctionWithMods if f.hasErasedParams => makeFunctionWithValDefs(f, pt)
     }
     desugared.withSpan(tree.span)
@@ -1927,7 +1932,7 @@ object desugar {
         }
         tree match
           case tree: FunctionWithMods =>
-            untpd.FunctionWithMods(applyVParams, tree.body, tree.mods, tree.erasedParams)
+            untpd.FunctionWithMods(applyVParams, result, tree.mods, tree.erasedParams)
           case _ => untpd.Function(applyVParams, result)
     }
   }
@@ -1986,15 +1991,13 @@ object desugar {
         trees foreach collect
       case Block(Nil, expr) =>
         collect(expr)
-      case Quote(expr) =>
+      case Quote(body, _) =>
         new UntypedTreeTraverser {
           def traverse(tree: untpd.Tree)(using Context): Unit = tree match {
-            case Splice(expr) => collect(expr)
+            case SplicePattern(body, _) => collect(body)
             case _ => traverseChildren(tree)
           }
-        }.traverse(expr)
-      case CapturingTypeTree(refs, parent) =>
-        collect(parent)
+        }.traverse(body)
       case _ =>
     }
     collect(tree)

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

@@ -223,9 +223,6 @@ trait TreeInfo[T <: Untyped] { self: Trees.Instance[T] =>
   /** Strip `=> T` to `T` and (under pureFunctions) `{refs}-> T` to `T` */
   def stripByNameType(tree: Tree)(using Context): Tree = unsplice(tree) match
     case ByNameTypeTree(t1) => t1
-    case untpd.CapturingTypeTree(_, parent) =>
-      val parent1 = stripByNameType(parent)
-      if parent1 eq parent then tree else parent1
     case _ => tree
 
   /** All type and value parameter symbols of this DefDef */
@@ -467,19 +464,21 @@ trait UntypedTreeInfo extends TreeInfo[Untyped] { self: Trees.Instance[Untyped]
     }
   }
 
-  /** Under pureFunctions: A builder and extractor for `=> T`, which is an alias for `{*}-> T`.
-   *  Only trees of the form `=> T` are matched; trees written directly as `{*}-> T`
+  /** Under pureFunctions: A builder and extractor for `=> T`, which is an alias for `->{cap} T`.
+   *  Only trees of the form `=> T` are matched; trees written directly as `->{cap} T`
    *  are ignored by the extractor.
    */
   object ImpureByNameTypeTree:
 
-    def apply(tp: ByNameTypeTree)(using Context): untpd.CapturingTypeTree =
-      untpd.CapturingTypeTree(
-        untpd.captureRoot.withSpan(tp.span.startPos) :: Nil, tp)
+    def apply(tp: Tree)(using Context): untpd.ByNameTypeTree =
+      untpd.ByNameTypeTree(
+        untpd.CapturesAndResult(
+          untpd.captureRoot.withSpan(tp.span.startPos) :: Nil, tp))
 
-    def unapply(tp: Tree)(using Context): Option[ByNameTypeTree] = tp match
-      case untpd.CapturingTypeTree(id @ Select(_, nme.CAPTURE_ROOT) :: Nil, bntp: ByNameTypeTree)
-      if id.span == bntp.span.startPos => Some(bntp)
+    def unapply(tp: Tree)(using Context): Option[Tree] = tp match
+      case untpd.ByNameTypeTree(
+        untpd.CapturesAndResult(id @ Select(_, nme.CAPTURE_ROOT) :: Nil, result))
+      if id.span == result.span.startPos => Some(result)
       case _ => None
   end ImpureByNameTypeTree
 }
@@ -1026,33 +1025,19 @@ trait TypedTreeInfo extends TreeInfo[Type] { self: Trees.Instance[Type] =>
       case t => assert(t.span.exists, i"$t")
     }
 
-  /** Extractors for quotes */
-  object Quoted {
+  object QuotedTypeOf {
     /** Extracts the content of a quoted tree.
      *  The result can be the contents of a term or type quote, which
      *  will return a term or type tree respectively.
      */
     def unapply(tree: tpd.Apply)(using Context): Option[tpd.Tree] =
-      if tree.symbol == defn.QuotedRuntime_exprQuote then
-        // quoted.runtime.Expr.quote[T](<body>)
-        Some(tree.args.head)
-      else if tree.symbol == defn.QuotedTypeModule_of then
+      if tree.symbol == defn.QuotedTypeModule_of then
         // quoted.Type.of[<body>](quotes)
         val TypeApply(_, body :: _) = tree.fun: @unchecked
         Some(body)
       else None
   }
 
-  /** Extractors for splices */
-  object Spliced {
-    /** Extracts the content of a spliced expression tree.
-     *  The result can be the contents of a term splice, which
-     *  will return a term tree.
-     */
-    def unapply(tree: tpd.Apply)(using Context): Option[tpd.Tree] =
-      if tree.symbol.isExprSplice then Some(tree.args.head) else None
-  }
-
   /** Extractors for type splices */
   object SplicedType {
     /** Extracts the content of a spliced type tree.

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

@@ -30,16 +30,10 @@ class TreeMapWithImplicits extends tpd.TreeMapWithPreciseStatContexts {
 
   private def patternScopeCtx(pattern: Tree)(using Context): Context = {
     val nestedCtx = ctx.fresh.setNewScope
-    new TreeTraverser {
-      def traverse(tree: Tree)(using Context): Unit = {
-        tree match {
-          case d: DefTree if d.symbol.isOneOf(GivenOrImplicitVal) =>
-            nestedCtx.enter(d.symbol)
-          case _ =>
-        }
-        traverseChildren(tree)
-      }
-    }.traverse(pattern)
+    pattern.foreachSubTree {
+      case d: DefTree if d.symbol.isOneOf(GivenOrImplicitVal) => nestedCtx.enter(d.symbol)
+      case _ =>
+    }
     nestedCtx
   }
 

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

@@ -146,11 +146,6 @@ class TreeTypeMap(
           val bind1 = tmap.transformSub(bind)
           val expr1 = tmap.transform(expr)
           cpy.Labeled(labeled)(bind1, expr1)
-        case tree @ Hole(_, _, args, content, tpt) =>
-          val args1 = args.mapConserve(transform)
-          val content1 = transform(content)
-          val tpt1 = transform(tpt)
-          cpy.Hole(tree)(args = args1, content = content1, tpt = tpt1)
         case tree1 =>
           super.transform(tree1)
       }