From 6e58d25acd99ff44533730867cfc09873cb95f7a Mon Sep 17 00:00:00 2001
From: Jan Chyb <jan.chyb.99@gmail.com>
Date: Thu, 22 Aug 2024 15:37:26 +0200
Subject: [PATCH 01/39] Avoid using the current denotation in
 NamedType.disambiguate

While recalculating denotation in NamedType we might call
NamedType.disambiguate which uses a denotation to decide about
the correct overloaded method. Using current denotation here might cause
stale symbol errors, so instead we use the lastKnownDenotation,
which should be enough for the use case here, as targetName should not
change between phases/runs.

Later in the denotation recalculation a similar thing happens with
SourceLanguage.apply, where we also now avoid using currentDenotation,
as whether the symbol comes from java or Scala 2 should
also not change between phases/runs.
---
 .../dotty/tools/dotc/core/Denotations.scala   |  2 +-
 .../dotty/tools/dotc/core/TypeErasure.scala   |  9 +++++++--
 .../src/dotty/tools/dotc/core/Types.scala     |  5 ++++-
 tests/pos-macros/i20574/Exports.scala         |  3 +++
 tests/pos-macros/i20574/Macros.scala          | 20 +++++++++++++++++++
 .../pos-macros/i20574/OverloadedInline.scala  | 13 ++++++++++++
 tests/pos-macros/i20574/Test.scala            |  5 +++++
 7 files changed, 53 insertions(+), 4 deletions(-)
 create mode 100644 tests/pos-macros/i20574/Exports.scala
 create mode 100644 tests/pos-macros/i20574/Macros.scala
 create mode 100644 tests/pos-macros/i20574/OverloadedInline.scala
 create mode 100644 tests/pos-macros/i20574/Test.scala

diff --git a/compiler/src/dotty/tools/dotc/core/Denotations.scala b/compiler/src/dotty/tools/dotc/core/Denotations.scala
index 60a7555456bf..816b28177333 100644
--- a/compiler/src/dotty/tools/dotc/core/Denotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/Denotations.scala
@@ -961,7 +961,7 @@ object Denotations {
     }
 
     def staleSymbolError(using Context): Nothing =
-      if symbol.isPackageObject && ctx.run != null && ctx.run.nn.isCompilingSuspended
+      if symbol.lastKnownDenotation.isPackageObject && ctx.run != null && ctx.run.nn.isCompilingSuspended
       then throw StaleSymbolTypeError(symbol)
       else throw StaleSymbolException(staleSymbolMsg)
 
diff --git a/compiler/src/dotty/tools/dotc/core/TypeErasure.scala b/compiler/src/dotty/tools/dotc/core/TypeErasure.scala
index ce4956e6e847..9491bdab9de8 100644
--- a/compiler/src/dotty/tools/dotc/core/TypeErasure.scala
+++ b/compiler/src/dotty/tools/dotc/core/TypeErasure.scala
@@ -24,11 +24,16 @@ enum SourceLanguage:
 object SourceLanguage:
   /** The language in which `sym` was defined. */
   def apply(sym: Symbol)(using Context): SourceLanguage =
-    if sym.is(JavaDefined) then
+    // We might be using this method while recalculating the denotation,
+    // so let's use `lastKnownDenotation`.
+    // This is ok as the source of the symbol and whether it is inline should
+    // not change between runs/phases.
+    val denot = sym.lastKnownDenotation
+    if denot.is(JavaDefined) then
       SourceLanguage.Java
     // Scala 2 methods don't have Inline set, except for the ones injected with `patchStdlibClass`
     // which are really Scala 3 methods.
-    else if sym.isClass && sym.is(Scala2x) || (sym.maybeOwner.is(Scala2x) && !sym.is(Inline)) then
+    else if denot.isClass && denot.is(Scala2x) || (denot.maybeOwner.lastKnownDenotation.is(Scala2x) && !denot.is(Inline)) then
       SourceLanguage.Scala2
     else
       SourceLanguage.Scala3
diff --git a/compiler/src/dotty/tools/dotc/core/Types.scala b/compiler/src/dotty/tools/dotc/core/Types.scala
index aba8c3bb31fd..8867f2fbe3db 100644
--- a/compiler/src/dotty/tools/dotc/core/Types.scala
+++ b/compiler/src/dotty/tools/dotc/core/Types.scala
@@ -2491,7 +2491,10 @@ object Types extends TypeUtils {
     }
 
     private def disambiguate(d: Denotation)(using Context): Denotation =
-      disambiguate(d, currentSignature, currentSymbol.targetName)
+      // this method might be triggered while the denotation is already being recomputed
+      // in NamedType, so it's better to use lastKnownDenotation instead, as targetName
+      // should not change between phases/runs
+      disambiguate(d, currentSignature, currentSymbol.lastKnownDenotation.targetName)
 
     private def disambiguate(d: Denotation, sig: Signature | Null, target: Name)(using Context): Denotation =
       if (sig != null)
diff --git a/tests/pos-macros/i20574/Exports.scala b/tests/pos-macros/i20574/Exports.scala
new file mode 100644
index 000000000000..328d832fad88
--- /dev/null
+++ b/tests/pos-macros/i20574/Exports.scala
@@ -0,0 +1,3 @@
+object Exports{
+  export OverloadedInline.*
+}
diff --git a/tests/pos-macros/i20574/Macros.scala b/tests/pos-macros/i20574/Macros.scala
new file mode 100644
index 000000000000..a40c1f361ce1
--- /dev/null
+++ b/tests/pos-macros/i20574/Macros.scala
@@ -0,0 +1,20 @@
+import scala.quoted.*
+
+object Macros{
+
+  inline def A() : String = {
+     ${ A_impl }
+  }
+
+  def A_impl(using Quotes): Expr[String] = {
+    Expr("Whatever")
+  }
+
+  inline def B[T]: Int = {
+    ${ B_Impl[T] }
+  }
+
+  def B_Impl[T](using Quotes): Expr[Int] = {
+    Expr(0)
+  }
+}
diff --git a/tests/pos-macros/i20574/OverloadedInline.scala b/tests/pos-macros/i20574/OverloadedInline.scala
new file mode 100644
index 000000000000..5bf2347c45c0
--- /dev/null
+++ b/tests/pos-macros/i20574/OverloadedInline.scala
@@ -0,0 +1,13 @@
+import Macros.*
+
+object OverloadedInline{
+
+    A()
+    inline def overloaded_inline[T]: Unit = {
+        overloaded_inline[T](0)
+    }
+
+    inline def overloaded_inline[T](dummy: Int): Unit = {
+        val crash = B[T]
+    }
+}
diff --git a/tests/pos-macros/i20574/Test.scala b/tests/pos-macros/i20574/Test.scala
new file mode 100644
index 000000000000..abc2b4eb0bc9
--- /dev/null
+++ b/tests/pos-macros/i20574/Test.scala
@@ -0,0 +1,5 @@
+import Exports.*
+
+object Test {
+   overloaded_inline[Unit]
+}

From 8258bb0e327a4c2fabaac23e39c3c860e0fb4038 Mon Sep 17 00:00:00 2001
From: Hamza Remmal <hamza@remmal.dev>
Date: Tue, 8 Oct 2024 15:57:11 +0200
Subject: [PATCH 02/39] Drop support for old experimental in community-build

---
 .../communitybuild/CommunityBuildRunner.scala   | 13 ++++++-------
 .../src/scala/dotty/communitybuild/Main.scala   |  5 +----
 .../scala/dotty/communitybuild/projects.scala   | 17 ++---------------
 3 files changed, 9 insertions(+), 26 deletions(-)

diff --git a/community-build/src/scala/dotty/communitybuild/CommunityBuildRunner.scala b/community-build/src/scala/dotty/communitybuild/CommunityBuildRunner.scala
index 6a0c54c4b00b..b3065fefe87f 100644
--- a/community-build/src/scala/dotty/communitybuild/CommunityBuildRunner.scala
+++ b/community-build/src/scala/dotty/communitybuild/CommunityBuildRunner.scala
@@ -16,13 +16,12 @@ object CommunityBuildRunner:
    *  and avoid network overhead. See https://github.com/lampepfl/dotty-drone
    *  for more infrastructural details.
    */
-  extension (self: CommunityProject) def run()(using suite: CommunityBuildRunner): Unit =
-    if self.requiresExperimental && !compilerSupportExperimental then
-      log(s"Skipping ${self.project} - it needs experimental features unsupported in this build.")
-      return
-    self.dependencies.foreach(_.publish())
-    self.testOnlyDependencies().foreach(_.publish())
-    suite.runProject(self)
+  extension (self: CommunityProject) 
+    def run()(using suite: CommunityBuildRunner): Unit =
+      self.dependencies.foreach(_.publish())
+      self.testOnlyDependencies().foreach(_.publish())
+      suite.runProject(self)
+  end extension
 
 trait CommunityBuildRunner:
 
diff --git a/community-build/src/scala/dotty/communitybuild/Main.scala b/community-build/src/scala/dotty/communitybuild/Main.scala
index 852cee46af22..c813f5ff684b 100644
--- a/community-build/src/scala/dotty/communitybuild/Main.scala
+++ b/community-build/src/scala/dotty/communitybuild/Main.scala
@@ -55,10 +55,7 @@ object Main:
         Seq("rm", "-rf", destStr).!
         Files.createDirectory(dest)
         val (toRun, ignored) =
-          allProjects.partition( p =>
-            p.docCommand != null
-            && (!p.requiresExperimental || compilerSupportExperimental)
-          )
+          allProjects.partition(_.docCommand != null)
 
         val paths = toRun.map { project =>
           val name = project.project
diff --git a/community-build/src/scala/dotty/communitybuild/projects.scala b/community-build/src/scala/dotty/communitybuild/projects.scala
index a0444505801a..e8d6c3d2894d 100644
--- a/community-build/src/scala/dotty/communitybuild/projects.scala
+++ b/community-build/src/scala/dotty/communitybuild/projects.scala
@@ -10,9 +10,6 @@ lazy val compilerVersion: String =
   val file = communitybuildDir.resolve("scala3-bootstrapped.version")
   new String(Files.readAllBytes(file), UTF_8)
 
-lazy val compilerSupportExperimental: Boolean =
-  compilerVersion.contains("SNAPSHOT") || compilerVersion.contains("NIGHTLY")
-
 lazy val sbtPluginFilePath: String =
   // Workaround for https://github.com/sbt/sbt/issues/4395
   new File(sys.props("user.home") + "/.sbt/1.0/plugins").mkdirs()
@@ -43,7 +40,6 @@ sealed trait CommunityProject:
   val testOnlyDependencies: () => List[CommunityProject]
   val binaryName: String
   val runCommandsArgs: List[String] = Nil
-  val requiresExperimental: Boolean
   val environment: Map[String, String] = Map.empty
 
   final val projectDir = communitybuildDir.resolve("community-projects").resolve(project)
@@ -53,7 +49,6 @@ sealed trait CommunityProject:
 
   /** Publish this project to the local Maven repository */
   final def publish(): Unit =
-    // TODO what should this do with .requiresExperimental?
     if !published then
       publishDependencies()
       log(s"Publishing $project")
@@ -65,11 +60,6 @@ sealed trait CommunityProject:
       published = true
 
   final def doc(): Unit =
-    if this.requiresExperimental && !compilerSupportExperimental then
-      log(
-        s"Skipping ${this.project} - it needs experimental features unsupported in this build."
-      )
-      return
     publishDependencies()
     log(s"Documenting $project")
     if docCommand eq null then
@@ -89,8 +79,7 @@ final case class MillCommunityProject(
     baseCommand: String,
     dependencies: List[CommunityProject] = Nil,
     testOnlyDependencies: () => List[CommunityProject] = () => Nil,
-    ignoreDocs: Boolean = false,
-    requiresExperimental: Boolean = false,
+    ignoreDocs: Boolean = false
     ) extends CommunityProject:
   override val binaryName: String = "./mill"
   override val testCommand = s"$baseCommand.test"
@@ -109,8 +98,7 @@ final case class SbtCommunityProject(
     testOnlyDependencies: () => List[CommunityProject] = () => Nil,
     sbtPublishCommand: String = null,
     sbtDocCommand: String = null,
-    scalacOptions: List[String] = SbtCommunityProject.scalacOptions,
-    requiresExperimental: Boolean = false,
+    scalacOptions: List[String] = SbtCommunityProject.scalacOptions
   ) extends CommunityProject:
   override val binaryName: String = "sbt"
 
@@ -260,7 +248,6 @@ object projects:
     project       = "intent",
     sbtTestCommand   = "test",
     sbtDocCommand = "doc",
-    requiresExperimental = true,
   )
 
   lazy val scalacheck = SbtCommunityProject(

From e0428038159bff79774fd49c889f824f302dba9d Mon Sep 17 00:00:00 2001
From: Jamie Thompson <bishbashboshjt@gmail.com>
Date: Fri, 11 Oct 2024 01:00:36 +0200
Subject: [PATCH 03/39] fix code rendering error in givens.md

an extra code fence was added, so the bottom of the page is incorrectly rendered
---
 docs/_docs/reference/contextual/givens.md | 2 --
 1 file changed, 2 deletions(-)

diff --git a/docs/_docs/reference/contextual/givens.md b/docs/_docs/reference/contextual/givens.md
index 088ded2e8db4..9c074da0da6e 100644
--- a/docs/_docs/reference/contextual/givens.md
+++ b/docs/_docs/reference/contextual/givens.md
@@ -90,8 +90,6 @@ time it is accessed. If the given is a mere alias to some immutable value, the g
 Here is the full syntax for given instances. Some of these forms of givens are explained in a separate page: [Other Forms of Givens](../more-givens.md).
 
 ```ebnf
-Here is the complete context-free syntax for all proposed features.
-```
 TmplDef           ::=  ... | 'given' GivenDef
 GivenDef          ::=  [id ':'] GivenSig
 GivenSig          ::=  GivenImpl

From 9de4b7c3b7a0d35f75a5dd050e2eca58b9fd5152 Mon Sep 17 00:00:00 2001
From: Seth Tisue <seth@tisue.net>
Date: Thu, 10 Oct 2024 18:24:04 -0700
Subject: [PATCH 04/39] REPL: JLine 3.27.0 (was 3.25.1)

---
 project/Build.scala | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/project/Build.scala b/project/Build.scala
index 84ce00d11577..60511f648b57 100644
--- a/project/Build.scala
+++ b/project/Build.scala
@@ -694,9 +694,9 @@ object Build {
       libraryDependencies ++= Seq(
         "org.scala-lang.modules" % "scala-asm" % "9.7.0-scala-2", // used by the backend
         Dependencies.compilerInterface,
-        "org.jline" % "jline-reader" % "3.25.1",   // used by the REPL
-        "org.jline" % "jline-terminal" % "3.25.1",
-        "org.jline" % "jline-terminal-jna" % "3.25.1", // needed for Windows
+        "org.jline" % "jline-reader" % "3.27.0",   // used by the REPL
+        "org.jline" % "jline-terminal" % "3.27.0",
+        "org.jline" % "jline-terminal-jna" % "3.27.0", // needed for Windows
         ("io.get-coursier" %% "coursier" % "2.0.16" % Test).cross(CrossVersion.for3Use2_13),
       ),
 

From aee3230df033af599847d460ecd16064af9c702c Mon Sep 17 00:00:00 2001
From: Tomasz Godzik <tgodzik@virtuslab.com>
Date: Fri, 11 Oct 2024 18:43:25 +0200
Subject: [PATCH 05/39] backport: include inline when printing param names

---
 .../tools/pc/printer/ShortenedTypePrinter.scala      |  3 ++-
 .../pc/tests/completion/CompletionArgSuite.scala     | 12 ++++++------
 .../pc/tests/completion/CompletionCancelSuite.scala  |  4 ++--
 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/presentation-compiler/src/main/dotty/tools/pc/printer/ShortenedTypePrinter.scala b/presentation-compiler/src/main/dotty/tools/pc/printer/ShortenedTypePrinter.scala
index a738440c585d..d9c11a5ada8c 100644
--- a/presentation-compiler/src/main/dotty/tools/pc/printer/ShortenedTypePrinter.scala
+++ b/presentation-compiler/src/main/dotty/tools/pc/printer/ShortenedTypePrinter.scala
@@ -527,7 +527,8 @@ class ShortenedTypePrinter(
         else if includeDefaultParam == ShortenedTypePrinter.IncludeDefaultParam.ResolveLater && isDefaultParam
         then " = ..."
         else "" // includeDefaultParam == Never or !isDefaultParam
-      s"$keywordName: ${paramTypeString}$default"
+      val inline = if(param.is(Flags.Inline)) "inline " else ""
+      s"$inline$keywordName: ${paramTypeString}$default"
     end if
   end paramLabel
 
diff --git a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionArgSuite.scala b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionArgSuite.scala
index 17f21b16d6e8..dc81d2596c6f 100644
--- a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionArgSuite.scala
+++ b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionArgSuite.scala
@@ -796,7 +796,7 @@ class CompletionArgSuite extends BaseCompletionSuite:
          |  def k: Int = m(1, a@@)
          |""".stripMargin,
       """|aaa = : Int
-         |assert(assertion: Boolean): Unit
+         |assert(inline assertion: Boolean): Unit
          |""".stripMargin,
       topLines = Some(2),
     )
@@ -810,7 +810,7 @@ class CompletionArgSuite extends BaseCompletionSuite:
          |  def k: Int = m(inn = 1, a@@)
          |""".stripMargin,
       """|aaa = : Int
-         |assert(assertion: Boolean): Unit
+         |assert(inline assertion: Boolean): Unit
          |""".stripMargin,
       topLines = Some(2),
     )
@@ -912,7 +912,7 @@ class CompletionArgSuite extends BaseCompletionSuite:
          |""".stripMargin,
       """|aaa = : Int
          |abb = : Option[Int]
-         |assert(assertion: Boolean): Unit
+         |assert(inline assertion: Boolean): Unit
          |""".stripMargin,
       topLines = Some(3),
     )
@@ -927,7 +927,7 @@ class CompletionArgSuite extends BaseCompletionSuite:
          |""".stripMargin,
       """|aaa = : Int
          |abb = : Option[Int]
-         |assert(assertion: Boolean): Unit
+         |assert(inline assertion: Boolean): Unit
          |""".stripMargin,
       topLines = Some(3),
     )
@@ -945,7 +945,7 @@ class CompletionArgSuite extends BaseCompletionSuite:
          |""".stripMargin,
       """|aaa = : Int
          |abb = : Option[Int]
-         |assert(assertion: Boolean): Unit
+         |assert(inline assertion: Boolean): Unit
          |""".stripMargin,
       topLines = Some(3),
     )
@@ -963,7 +963,7 @@ class CompletionArgSuite extends BaseCompletionSuite:
          |""".stripMargin,
       """|abb = : Option[Int]
          |acc = : List[Int]
-         |assert(assertion: Boolean): Unit
+         |assert(inline assertion: Boolean): Unit
          |""".stripMargin,
       topLines = Some(3),
     )
diff --git a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionCancelSuite.scala b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionCancelSuite.scala
index 4746eb93f25d..c1d0e017def7 100644
--- a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionCancelSuite.scala
+++ b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionCancelSuite.scala
@@ -90,8 +90,8 @@ class CompletionCancelSuite extends BaseCompletionSuite:
         |  val x = asser@@
         |}
       """.stripMargin,
-      """|assert(assertion: Boolean): Unit
-         |assert(assertion: Boolean, message: => Any): Unit
+      """|assert(inline assertion: Boolean): Unit
+         |assert(inline assertion: Boolean, inline message: => Any): Unit
          |""".stripMargin
     )
 

From 6429b4b05bfc6904ef1fe76589a3bfe833383ef9 Mon Sep 17 00:00:00 2001
From: Tomasz Godzik <tgodzik@virtuslab.com>
Date: Fri, 11 Oct 2024 18:45:20 +0200
Subject: [PATCH 06/39] backport: use uri from params in pc for location

---
 .../src/main/dotty/tools/pc/PcDefinitionProvider.scala    | 8 ++++----
 .../dotty/tools/pc/utils/InteractiveEnrichments.scala     | 6 ------
 2 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala b/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala
index fc97dd1f1176..6f2f4cd5f34e 100644
--- a/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala
+++ b/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala
@@ -131,13 +131,13 @@ class PcDefinitionProvider(
           otherDefs.headOption.orElse(exportedDefs.headOption)  match
             case Some(srcTree) =>
               val pos = srcTree.namePos
-              pos.toLocation match
-                case None => DefinitionResultImpl.empty
-                case Some(loc) =>
+              if pos.exists then
+                  val loc = new Location(params.uri().toString(), pos.toLsp)
                   DefinitionResultImpl(
                     SemanticdbSymbols.symbolName(sym),
-                    List(loc).asJava
+                    List(loc).asJava,
                   )
+                else DefinitionResultImpl.empty
             case None =>
               DefinitionResultImpl.empty
         else
diff --git a/presentation-compiler/src/main/dotty/tools/pc/utils/InteractiveEnrichments.scala b/presentation-compiler/src/main/dotty/tools/pc/utils/InteractiveEnrichments.scala
index 8ff11694ff1c..66080a363d51 100644
--- a/presentation-compiler/src/main/dotty/tools/pc/utils/InteractiveEnrichments.scala
+++ b/presentation-compiler/src/main/dotty/tools/pc/utils/InteractiveEnrichments.scala
@@ -99,12 +99,6 @@ object InteractiveEnrichments extends CommonMtagsEnrichments:
     def focusAt(point: Int): SourcePosition =
       pos.withSpan(pos.span.withPoint(point).focus)
 
-    def toLocation: Option[l.Location] =
-      for
-        uri <- InteractiveDriver.toUriOption(pos.source)
-        range <- if pos.exists then Some(pos.toLsp) else None
-      yield new l.Location(uri.toString(), range)
-
     def encloses(other: SourcePosition): Boolean =
       pos.start <= other.start && pos.end >= other.end
 

From 87db0da58d70ace996b65c179baa48929526ab22 Mon Sep 17 00:00:00 2001
From: Tomasz Godzik <tgodzik@virtuslab.com>
Date: Fri, 11 Oct 2024 19:02:02 +0200
Subject: [PATCH 07/39] backport: Finer grained accessibility check for
 auto-imports

---
 .../tools/pc/CompilerSearchVisitor.scala      |  2 +-
 .../dotty/tools/pc/PcDefinitionProvider.scala |  2 +-
 .../completion/CompletionSnippetSuite.scala   | 23 +++++++++++++++++++
 .../pc/tests/completion/CompletionSuite.scala | 13 +++++++++++
 4 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/presentation-compiler/src/main/dotty/tools/pc/CompilerSearchVisitor.scala b/presentation-compiler/src/main/dotty/tools/pc/CompilerSearchVisitor.scala
index 035c1062a3e3..9fb84ee1f513 100644
--- a/presentation-compiler/src/main/dotty/tools/pc/CompilerSearchVisitor.scala
+++ b/presentation-compiler/src/main/dotty/tools/pc/CompilerSearchVisitor.scala
@@ -28,7 +28,7 @@ class CompilerSearchVisitor(
     owner.isStatic && owner.isPublic
 
   private def isAccessible(sym: Symbol): Boolean = try
-    sym != NoSymbol && sym.isPublic && sym.isStatic || isAccessibleImplicitClass(sym)
+    (sym != NoSymbol && sym.isAccessibleFrom(ctx.owner.info) && sym.isStatic) || isAccessibleImplicitClass(sym)
   catch
     case err: AssertionError =>
       logger.log(Level.WARNING, err.getMessage())
diff --git a/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala b/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala
index 6f2f4cd5f34e..3b2284bef1d0 100644
--- a/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala
+++ b/presentation-compiler/src/main/dotty/tools/pc/PcDefinitionProvider.scala
@@ -137,7 +137,7 @@ class PcDefinitionProvider(
                     SemanticdbSymbols.symbolName(sym),
                     List(loc).asJava,
                   )
-                else DefinitionResultImpl.empty
+              else DefinitionResultImpl.empty
             case None =>
               DefinitionResultImpl.empty
         else
diff --git a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSnippetSuite.scala b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSnippetSuite.scala
index 381375c65131..a002e722f1f0 100644
--- a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSnippetSuite.scala
+++ b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSnippetSuite.scala
@@ -385,6 +385,29 @@ class CompletionSnippetSuite extends BaseCompletionSuite:
     )
 
   @Test def `no-apply` =
+    checkSnippet(
+      s"""|package example
+          |
+          |object Widget{}
+          |object Main {
+          |  Wi@@
+          |}
+          |""".stripMargin,
+      """|Widget -  example
+         |Window -  java.awt
+         |WindowPeer -  java.awt.peer
+         |WithFilter - [A](p: A => Boolean, xs: Array[A]): WithFilter[A]
+         |WithFilter - [A, CC[_$$2]](self: IterableOps[A, CC, ?], p: A => Boolean): WithFilter[A, CC]
+         |WithFilter - [K, V, IterableCC[_$$3], CC[_$$4,_$$5] <: IterableOps[?, AnyConstr, ?]](self: MapOps[K, V, CC, ?] & IterableOps[(K, V), IterableCC, ?], p: ((K, V)) => Boolean): WithFilter[K, V, IterableCC, CC]
+         |WithFilter - [K, V, IterableCC[_$$1], MapCC[X,Y] <: scala.collection.Map[X, Y], CC[X,Y] <: scala.collection.Map[X, Y] & SortedMapOps[X, Y, CC, ?]](self: SortedMapOps[K, V, CC, ?] & MapOps[K, V, MapCC, ?] & IterableOps[(K, V), IterableCC, ?], p: ((K, V)) => Boolean): WithFilter[K, V, IterableCC, MapCC, CC]
+         |WithFilter - [A, IterableCC[_$$1], CC[X] <: SortedSet[X]](self: SortedSetOps[A, CC, ?] & IterableOps[A, IterableCC, ?], p: A => Boolean): WithFilter[A, IterableCC, CC]
+         |WithFilter - (p: Char => Boolean, s: String): WithFilter
+         |WithFilter - [A](l: Stream[A] @uncheckedVariance, p: A => Boolean): WithFilter[A]
+         |""".stripMargin,
+      includeDetail = true,
+    )
+
+  @Test def `no-apply2` =
     checkSnippet(
       s"""|package example
           |
diff --git a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSuite.scala b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSuite.scala
index 57975d2c8e98..1d525c17bdf1 100644
--- a/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSuite.scala
+++ b/presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSuite.scala
@@ -2107,6 +2107,19 @@ class CompletionSuite extends BaseCompletionSuite:
         |""".stripMargin
    )
 
+  @Test def `shadowing` =
+   check(
+     """|package pkg
+        |object Main {
+        |  val x = ListBuff@@
+        |}
+        |""".stripMargin,
+     """|ListBuffer[A](elems: A*): ListBuffer[A] - scala.collection.mutable
+        |new ListBuffer[A]: ListBuffer[A] - scala.collection.mutable
+        |ListBuffer - scala.collection.mutable
+        |""".stripMargin
+   )
+
   @Test def `conflict-edit-2` =
     checkEdit(
       """|package a

From d459140ef14fe66644f90b9cc3b359e3cb3741ce Mon Sep 17 00:00:00 2001
From: Alexander <azazf93@gmail.com>
Date: Thu, 10 Oct 2024 22:18:26 +0300
Subject: [PATCH 08/39] Do not consider uninhabited constructors when
 performing exhaustive match checking

---
 .../tools/dotc/transform/patmat/Space.scala   | 35 ++++++++++++++-----
 tests/init-global/pos/i18629.scala            |  2 +-
 tests/patmat/i13931.scala                     |  2 +-
 tests/warn/patmat-nothing-exhaustive.scala    | 10 ++++++
 4 files changed, 38 insertions(+), 11 deletions(-)
 create mode 100644 tests/warn/patmat-nothing-exhaustive.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/patmat/Space.scala b/compiler/src/dotty/tools/dotc/transform/patmat/Space.scala
index 20b0099d82e2..9fb3c00c67c4 100644
--- a/compiler/src/dotty/tools/dotc/transform/patmat/Space.scala
+++ b/compiler/src/dotty/tools/dotc/transform/patmat/Space.scala
@@ -648,21 +648,38 @@ object SpaceEngine {
         // we get
         //    <== refineUsingParent(NatT, class Succ, []) = Succ[NatT]
         //    <== isSub(Succ[NatT] <:< Succ[Succ[<?>]]) = false
-        def getAppliedClass(tp: Type): Type = tp match
-          case tp @ AppliedType(_: HKTypeLambda, _)                        => tp
-          case tp @ AppliedType(tycon: TypeRef, _) if tycon.symbol.isClass => tp
+        def getAppliedClass(tp: Type): (Type, List[Type]) = tp match
+          case tp @ AppliedType(_: HKTypeLambda, _)                        => (tp, Nil)
+          case tp @ AppliedType(tycon: TypeRef, _) if tycon.symbol.isClass => (tp, tp.args)
           case tp @ AppliedType(tycon: TypeProxy, _)                       => getAppliedClass(tycon.superType.applyIfParameterized(tp.args))
-          case tp                                                          => tp
-        val tp = getAppliedClass(tpOriginal)
-        def getChildren(sym: Symbol): List[Symbol] =
+          case tp                                                          => (tp, Nil)
+        val (tp, typeArgs) = getAppliedClass(tpOriginal)
+        // This function is needed to get the arguments of the types that will be applied to the class.
+        // This is necessary because if the arguments of the types contain Nothing, 
+        // then this can affect whether the class will be taken into account during the exhaustiveness check
+        def getTypeArgs(parent: Symbol, child: Symbol, typeArgs: List[Type]): List[Type] =
+          val superType = child.typeRef.superType
+          if typeArgs.exists(_.isBottomType) && superType.isInstanceOf[ClassInfo] then
+            val parentClass = superType.asInstanceOf[ClassInfo].declaredParents.find(_.classSymbol == parent).get
+            val paramTypeMap = Map.from(parentClass.argTypes.map(_.typeSymbol).zip(typeArgs))
+            val substArgs = child.typeRef.typeParamSymbols.map(param => paramTypeMap.getOrElse(param, WildcardType))
+            substArgs
+          else Nil
+        def getChildren(sym: Symbol, typeArgs: List[Type]): List[Symbol] =
           sym.children.flatMap { child =>
             if child eq sym then List(sym) // i3145: sealed trait Baz, val x = new Baz {}, Baz.children returns Baz...
             else if tp.classSymbol == defn.TupleClass || tp.classSymbol == defn.NonEmptyTupleClass then
               List(child) // TupleN and TupleXXL classes are used for Tuple, but they aren't Tuple's children
-            else if (child.is(Private) || child.is(Sealed)) && child.isOneOf(AbstractOrTrait) then getChildren(child)
-            else List(child)
+            else if (child.is(Private) || child.is(Sealed)) && child.isOneOf(AbstractOrTrait) then
+              getChildren(child, getTypeArgs(sym, child, typeArgs))
+            else
+              val childSubstTypes = child.typeRef.applyIfParameterized(getTypeArgs(sym, child, typeArgs))
+              // if a class contains a field of type Nothing,
+              // then it can be ignored in pattern matching, because it is impossible to obtain an instance of it
+              val existFieldWithBottomType = childSubstTypes.fields.exists(_.info.isBottomType)
+              if existFieldWithBottomType then Nil else List(child)
           }
-        val children = trace(i"getChildren($tp)")(getChildren(tp.classSymbol))
+        val children = trace(i"getChildren($tp)")(getChildren(tp.classSymbol, typeArgs))
 
         val parts = children.map { sym =>
           val sym1 = if (sym.is(ModuleClass)) sym.sourceModule else sym
diff --git a/tests/init-global/pos/i18629.scala b/tests/init-global/pos/i18629.scala
index f97c21ee918d..03f1f5d5cda4 100644
--- a/tests/init-global/pos/i18629.scala
+++ b/tests/init-global/pos/i18629.scala
@@ -1,6 +1,6 @@
 object Foo {
   val bar = List() match {
     case List() => ???
-    case _ => ???
+    case null => ???
   }
 }
diff --git a/tests/patmat/i13931.scala b/tests/patmat/i13931.scala
index 0d8d9eb9dcd3..562f059771c1 100644
--- a/tests/patmat/i13931.scala
+++ b/tests/patmat/i13931.scala
@@ -3,5 +3,5 @@ class Test:
     case Seq() => println("empty")
     case _ => println("non-empty")
 
-  def test2 = IndexedSeq() match { case IndexedSeq() => case _ => }
+  def test2 = IndexedSeq() match { case IndexedSeq() => case null => }
   def test3 = IndexedSeq() match { case IndexedSeq(1) => case _ => }
diff --git a/tests/warn/patmat-nothing-exhaustive.scala b/tests/warn/patmat-nothing-exhaustive.scala
new file mode 100644
index 000000000000..4e9181256fda
--- /dev/null
+++ b/tests/warn/patmat-nothing-exhaustive.scala
@@ -0,0 +1,10 @@
+enum TestAdt:
+  case Inhabited
+  case Uninhabited(no: Nothing)
+
+def test1(t: TestAdt): Int = t match
+  case TestAdt.Inhabited => 1
+
+def test2(o: Option[Option[Nothing]]): Int = o match
+  case Some(None) => 1
+  case None => 2

From c6b23cc2944c183a36bc607e1eed9361cc9e3b83 Mon Sep 17 00:00:00 2001
From: Jamie Thompson <bishbashboshjt@gmail.com>
Date: Mon, 14 Oct 2024 15:20:12 +0200
Subject: [PATCH 09/39] backend computes line number from source of position

---
 .../src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala    | 8 +++++++-
 compiler/src/dotty/tools/dotc/util/SourceFile.scala       | 3 ++-
 compiler/src/dotty/tools/dotc/util/SourcePosition.scala   | 4 ++++
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala b/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala
index 394700c2898e..38e5617fc3d7 100644
--- a/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala
+++ b/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala
@@ -623,7 +623,13 @@ trait BCodeSkelBuilder extends BCodeHelpers {
       }
 
       if (emitLines && tree.span.exists && !tree.hasAttachment(SyntheticUnit)) {
-        val nr = ctx.source.offsetToLine(tree.span.point) + 1
+        val nr =
+          val sourcePos = tree.sourcePos
+          (
+            if sourcePos.exists then sourcePos.finalPosition.line
+            else ctx.source.offsetToLine(tree.span.point) // fallback
+          ) + 1
+
         if (nr != lastEmittedLineNr) {
           lastEmittedLineNr = nr
           getNonLabelNode(lastInsn) match {
diff --git a/compiler/src/dotty/tools/dotc/util/SourceFile.scala b/compiler/src/dotty/tools/dotc/util/SourceFile.scala
index 9da4f58f2deb..3ea43d16a7c8 100644
--- a/compiler/src/dotty/tools/dotc/util/SourceFile.scala
+++ b/compiler/src/dotty/tools/dotc/util/SourceFile.scala
@@ -119,7 +119,8 @@ class SourceFile(val file: AbstractFile, computeContent: => Array[Char]) extends
    *  For regular source files, simply return the argument.
    */
   def positionInUltimateSource(position: SourcePosition): SourcePosition =
-    SourcePosition(underlying, position.span shift start)
+    if isSelfContained then position // return the argument
+    else SourcePosition(underlying, position.span shift start)
 
   private def calculateLineIndicesFromContents() = {
     val cs = content()
diff --git a/compiler/src/dotty/tools/dotc/util/SourcePosition.scala b/compiler/src/dotty/tools/dotc/util/SourcePosition.scala
index 904704b2349c..384d2f1fb2f3 100644
--- a/compiler/src/dotty/tools/dotc/util/SourcePosition.scala
+++ b/compiler/src/dotty/tools/dotc/util/SourcePosition.scala
@@ -79,6 +79,10 @@ extends SrcPos, interfaces.SourcePosition, Showable {
     rec(this)
   }
 
+  def finalPosition: SourcePosition = {
+    source.positionInUltimateSource(this)
+  }
+
 
   override def toString: String =
     s"${if (source.exists) source.file.toString else "(no source)"}:$span"

From 731f61e567fde22cf463bc544b6aea1e8b159910 Mon Sep 17 00:00:00 2001
From: Adrien Piquerez <adrien.piquerez@gmail.com>
Date: Mon, 14 Oct 2024 16:47:53 +0200
Subject: [PATCH 10/39] Shade scalajs.ir under dotty.tools

---
 .../dotty/tools/backend/sjs/JSCodeGen.scala   | 14 ++++----
 .../dotty/tools/backend/sjs/JSEncoding.scala  | 12 +++----
 .../tools/backend/sjs/JSExportsGen.scala      | 14 ++++----
 .../dotty/tools/backend/sjs/JSPositions.scala |  2 +-
 .../tools/dotc/transform/CheckReentrant.scala |  2 +-
 .../tools/dotc/transform/sjs/JSSymUtils.scala |  2 +-
 .../dotc/transform/sjs/PrepJSExports.scala    |  4 +--
 .../dotc/transform/sjs/PrepJSInterop.scala    |  2 +-
 project/Build.scala                           | 35 +++++++++++++++----
 .../backend/sjs/JSCodeGen.scala               | 12 +++----
 .../backend/sjs/JSEncoding.scala              | 12 +++----
 .../backend/sjs/JSExportsGen.scala            | 12 +++----
 .../backend/sjs/JSPositions.scala             |  2 +-
 13 files changed, 73 insertions(+), 52 deletions(-)

diff --git a/compiler/src/dotty/tools/backend/sjs/JSCodeGen.scala b/compiler/src/dotty/tools/backend/sjs/JSCodeGen.scala
index 6e2449b5c299..7ba39768871b 100644
--- a/compiler/src/dotty/tools/backend/sjs/JSCodeGen.scala
+++ b/compiler/src/dotty/tools/backend/sjs/JSCodeGen.scala
@@ -25,13 +25,13 @@ import dotty.tools.dotc.transform.{Erasure, ValueClasses}
 import dotty.tools.dotc.util.SourcePosition
 import dotty.tools.dotc.report
 
-import org.scalajs.ir
-import org.scalajs.ir.{ClassKind, Position, Names => jsNames, Trees => js, Types => jstpe}
-import org.scalajs.ir.Names.{ClassName, MethodName, SimpleMethodName}
-import org.scalajs.ir.OriginalName
-import org.scalajs.ir.OriginalName.NoOriginalName
-import org.scalajs.ir.Trees.OptimizerHints
-import org.scalajs.ir.Version.Unversioned
+import dotty.tools.sjs.ir
+import dotty.tools.sjs.ir.{ClassKind, Position, Names => jsNames, Trees => js, Types => jstpe}
+import dotty.tools.sjs.ir.Names.{ClassName, MethodName, SimpleMethodName}
+import dotty.tools.sjs.ir.OriginalName
+import dotty.tools.sjs.ir.OriginalName.NoOriginalName
+import dotty.tools.sjs.ir.Trees.OptimizerHints
+import dotty.tools.sjs.ir.Version.Unversioned
 
 import dotty.tools.dotc.transform.sjs.JSSymUtils.*
 
diff --git a/compiler/src/dotty/tools/backend/sjs/JSEncoding.scala b/compiler/src/dotty/tools/backend/sjs/JSEncoding.scala
index 098f592daa30..9a7753680bc3 100644
--- a/compiler/src/dotty/tools/backend/sjs/JSEncoding.scala
+++ b/compiler/src/dotty/tools/backend/sjs/JSEncoding.scala
@@ -15,12 +15,12 @@ import StdNames.*
 
 import dotty.tools.dotc.transform.sjs.JSSymUtils.*
 
-import org.scalajs.ir
-import org.scalajs.ir.{Trees => js, Types => jstpe}
-import org.scalajs.ir.Names.{LocalName, LabelName, SimpleFieldName, FieldName, SimpleMethodName, MethodName, ClassName}
-import org.scalajs.ir.OriginalName
-import org.scalajs.ir.OriginalName.NoOriginalName
-import org.scalajs.ir.UTF8String
+import dotty.tools.sjs.ir
+import dotty.tools.sjs.ir.{Trees => js, Types => jstpe}
+import dotty.tools.sjs.ir.Names.{LocalName, LabelName, SimpleFieldName, FieldName, SimpleMethodName, MethodName, ClassName}
+import dotty.tools.sjs.ir.OriginalName
+import dotty.tools.sjs.ir.OriginalName.NoOriginalName
+import dotty.tools.sjs.ir.UTF8String
 
 import dotty.tools.backend.jvm.DottyBackendInterface.symExtensions
 
diff --git a/compiler/src/dotty/tools/backend/sjs/JSExportsGen.scala b/compiler/src/dotty/tools/backend/sjs/JSExportsGen.scala
index b5f9446758a9..e6c73357aa4c 100644
--- a/compiler/src/dotty/tools/backend/sjs/JSExportsGen.scala
+++ b/compiler/src/dotty/tools/backend/sjs/JSExportsGen.scala
@@ -22,12 +22,12 @@ import TypeErasure.ErasedValueType
 import dotty.tools.dotc.util.{SourcePosition, SrcPos}
 import dotty.tools.dotc.report
 
-import org.scalajs.ir.{Position, Names => jsNames, Trees => js, Types => jstpe}
-import org.scalajs.ir.Names.DefaultModuleID
-import org.scalajs.ir.OriginalName.NoOriginalName
-import org.scalajs.ir.Position.NoPosition
-import org.scalajs.ir.Trees.OptimizerHints
-import org.scalajs.ir.Version.Unversioned
+import dotty.tools.sjs.ir.{Position, Names => jsNames, Trees => js, Types => jstpe}
+import dotty.tools.sjs.ir.Names.DefaultModuleID
+import dotty.tools.sjs.ir.OriginalName.NoOriginalName
+import dotty.tools.sjs.ir.Position.NoPosition
+import dotty.tools.sjs.ir.Trees.OptimizerHints
+import dotty.tools.sjs.ir.Version.Unversioned
 
 import dotty.tools.dotc.transform.sjs.JSExportUtils.*
 import dotty.tools.dotc.transform.sjs.JSSymUtils.*
@@ -932,7 +932,7 @@ final class JSExportsGen(jsCodeGen: JSCodeGen)(using Context) {
         InstanceOfTypeTest(tpe.tycon.typeSymbol.typeRef)
 
       case _ =>
-        import org.scalajs.ir.Names
+        import dotty.tools.sjs.ir.Names
 
         (toIRType(tpe): @unchecked) match {
           case jstpe.AnyType => NoTypeTest
diff --git a/compiler/src/dotty/tools/backend/sjs/JSPositions.scala b/compiler/src/dotty/tools/backend/sjs/JSPositions.scala
index 3b25187b0acd..a229c9ea0e58 100644
--- a/compiler/src/dotty/tools/backend/sjs/JSPositions.scala
+++ b/compiler/src/dotty/tools/backend/sjs/JSPositions.scala
@@ -13,7 +13,7 @@ import dotty.tools.dotc.report
 import dotty.tools.dotc.util.{SourceFile, SourcePosition}
 import dotty.tools.dotc.util.Spans.Span
 
-import org.scalajs.ir
+import dotty.tools.sjs.ir
 
 /** Conversion utilities from dotty Positions to IR Positions. */
 class JSPositions()(using Context) {
diff --git a/compiler/src/dotty/tools/dotc/transform/CheckReentrant.scala b/compiler/src/dotty/tools/dotc/transform/CheckReentrant.scala
index 073086ac5e2c..e8a402068bfc 100644
--- a/compiler/src/dotty/tools/dotc/transform/CheckReentrant.scala
+++ b/compiler/src/dotty/tools/dotc/transform/CheckReentrant.scala
@@ -43,7 +43,7 @@ class CheckReentrant extends MiniPhase {
     requiredClass("scala.annotation.internal.unshared"))
 
   private val scalaJSIRPackageClass = new CtxLazy(
-    getPackageClassIfDefined("org.scalajs.ir"))
+    getPackageClassIfDefined("dotty.tools.sjs.ir"))
 
   def isIgnored(sym: Symbol)(using Context): Boolean =
     sym.hasAnnotation(sharableAnnot()) ||
diff --git a/compiler/src/dotty/tools/dotc/transform/sjs/JSSymUtils.scala b/compiler/src/dotty/tools/dotc/transform/sjs/JSSymUtils.scala
index 936b6958fb33..87ee2be91465 100644
--- a/compiler/src/dotty/tools/dotc/transform/sjs/JSSymUtils.scala
+++ b/compiler/src/dotty/tools/dotc/transform/sjs/JSSymUtils.scala
@@ -17,7 +17,7 @@ import Types.*
 
 import dotty.tools.backend.sjs.JSDefinitions.jsdefn
 
-import org.scalajs.ir.{Trees => js}
+import dotty.tools.sjs.ir.{Trees => js}
 
 /** Additional extensions for `Symbol`s that are only relevant for Scala.js. */
 object JSSymUtils {
diff --git a/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSExports.scala b/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSExports.scala
index f66141bff8ad..5aa35a277cb5 100644
--- a/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSExports.scala
+++ b/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSExports.scala
@@ -21,8 +21,8 @@ import dotty.tools.backend.sjs.JSDefinitions.jsdefn
 import JSExportUtils.*
 import JSSymUtils.*
 
-import org.scalajs.ir.Names.DefaultModuleID
-import org.scalajs.ir.Trees.TopLevelExportDef.isValidTopLevelExportName
+import dotty.tools.sjs.ir.Names.DefaultModuleID
+import dotty.tools.sjs.ir.Trees.TopLevelExportDef.isValidTopLevelExportName
 
 object PrepJSExports {
   import tpd.*
diff --git a/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSInterop.scala b/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSInterop.scala
index 1b8fdd268ece..c7316482c193 100644
--- a/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSInterop.scala
+++ b/compiler/src/dotty/tools/dotc/transform/sjs/PrepJSInterop.scala
@@ -23,7 +23,7 @@ import Types.*
 
 import JSSymUtils.*
 
-import org.scalajs.ir.Trees.JSGlobalRef
+import dotty.tools.sjs.ir.Trees.JSGlobalRef
 
 import dotty.tools.backend.sjs.JSDefinitions.jsdefn
 
diff --git a/project/Build.scala b/project/Build.scala
index 84ce00d11577..0cf4e3abcaaf 100644
--- a/project/Build.scala
+++ b/project/Build.scala
@@ -616,18 +616,36 @@ object Build {
   def findArtifactPath(classpath: Def.Classpath, name: String): String =
     findArtifact(classpath, name).getAbsolutePath
 
+  /** Replace package names in package definitions, for shading.
+   * It assumes the full package def is written on a single line.
+   * It does not adapt the imports accordingly.
+   */
+  def replacePackage(lines: List[String])(replace: PartialFunction[String, String]): List[String] = {
+    def recur(lines: List[String]): List[String] =
+      lines match {
+        case head :: tail =>
+          if (head.startsWith("package ")) {
+            val packageName = head.stripPrefix("package ").trim
+            val newPackageName = replace.applyOrElse(packageName, (_: String) => packageName)
+            s"package $newPackageName" :: tail
+          } else head :: recur(tail)
+        case _ => lines
+      }
+    recur(lines)
+  }
+
   /** Insert UnsafeNulls Import after package */
-  def insertUnsafeNullsImport(lines: Seq[String]): Seq[String] = {
-    def recur(ls: Seq[String], foundPackage: Boolean): Seq[String] = ls match {
-      case Seq(l, rest @ _*) =>
+  def insertUnsafeNullsImport(lines: List[String]): List[String] = {
+    def recur(ls: List[String], foundPackage: Boolean): List[String] = ls match {
+      case l :: rest =>
         val lt = l.trim()
         if (foundPackage) {
           if (!(lt.isEmpty || lt.startsWith("package ")))
-            "import scala.language.unsafeNulls" +: ls
-          else l +: recur(rest, foundPackage)
+            "import scala.language.unsafeNulls" :: ls
+          else l :: recur(rest, foundPackage)
         } else {
           if (lt.startsWith("package ")) l +: recur(rest, true)
-          else l +: recur(rest, foundPackage)
+          else l :: recur(rest, foundPackage)
         }
       case _ => ls
     }
@@ -928,7 +946,10 @@ object Build {
           val sjsSources = (trgDir ** "*.scala").get.toSet
           sjsSources.foreach(f => {
             val lines = IO.readLines(f)
-            IO.writeLines(f, insertUnsafeNullsImport(lines))
+            val linesWithPackage = replacePackage(lines) {
+              case "org.scalajs.ir" => "dotty.tools.sjs.ir"
+            }
+            IO.writeLines(f, insertUnsafeNullsImport(linesWithPackage))
           })
           sjsSources
         } (Set(scalaJSIRSourcesJar)).toSeq
diff --git a/tests/pos-with-compiler-cc/backend/sjs/JSCodeGen.scala b/tests/pos-with-compiler-cc/backend/sjs/JSCodeGen.scala
index c670b2de97b1..81f09b082850 100644
--- a/tests/pos-with-compiler-cc/backend/sjs/JSCodeGen.scala
+++ b/tests/pos-with-compiler-cc/backend/sjs/JSCodeGen.scala
@@ -25,12 +25,12 @@ import dotty.tools.dotc.transform.SymUtils._
 import dotty.tools.dotc.util.SourcePosition
 import dotty.tools.dotc.report
 
-import org.scalajs.ir
-import org.scalajs.ir.{ClassKind, Position, Names => jsNames, Trees => js, Types => jstpe}
-import org.scalajs.ir.Names.{ClassName, MethodName, SimpleMethodName}
-import org.scalajs.ir.OriginalName
-import org.scalajs.ir.OriginalName.NoOriginalName
-import org.scalajs.ir.Trees.OptimizerHints
+import dotty.tools.sjs.ir
+import dotty.tools.sjs.ir.{ClassKind, Position, Names => jsNames, Trees => js, Types => jstpe}
+import dotty.tools.sjs.ir.Names.{ClassName, MethodName, SimpleMethodName}
+import dotty.tools.sjs.ir.OriginalName
+import dotty.tools.sjs.ir.OriginalName.NoOriginalName
+import dotty.tools.sjs.ir.Trees.OptimizerHints
 
 import dotty.tools.dotc.transform.sjs.JSSymUtils._
 
diff --git a/tests/pos-with-compiler-cc/backend/sjs/JSEncoding.scala b/tests/pos-with-compiler-cc/backend/sjs/JSEncoding.scala
index 73a150c60290..518295543610 100644
--- a/tests/pos-with-compiler-cc/backend/sjs/JSEncoding.scala
+++ b/tests/pos-with-compiler-cc/backend/sjs/JSEncoding.scala
@@ -15,12 +15,12 @@ import StdNames._
 
 import dotty.tools.dotc.transform.sjs.JSSymUtils._
 
-import org.scalajs.ir
-import org.scalajs.ir.{Trees => js, Types => jstpe}
-import org.scalajs.ir.Names.{LocalName, LabelName, FieldName, SimpleMethodName, MethodName, ClassName}
-import org.scalajs.ir.OriginalName
-import org.scalajs.ir.OriginalName.NoOriginalName
-import org.scalajs.ir.UTF8String
+import dotty.tools.sjs.ir
+import dotty.tools.sjs.ir.{Trees => js, Types => jstpe}
+import dotty.tools.sjs.ir.Names.{LocalName, LabelName, FieldName, SimpleMethodName, MethodName, ClassName}
+import dotty.tools.sjs.ir.OriginalName
+import dotty.tools.sjs.ir.OriginalName.NoOriginalName
+import dotty.tools.sjs.ir.UTF8String
 
 import dotty.tools.backend.jvm.DottyBackendInterface.symExtensions
 
diff --git a/tests/pos-with-compiler-cc/backend/sjs/JSExportsGen.scala b/tests/pos-with-compiler-cc/backend/sjs/JSExportsGen.scala
index 78412999bb34..82b69e6a16a7 100644
--- a/tests/pos-with-compiler-cc/backend/sjs/JSExportsGen.scala
+++ b/tests/pos-with-compiler-cc/backend/sjs/JSExportsGen.scala
@@ -22,11 +22,11 @@ import TypeErasure.ErasedValueType
 import dotty.tools.dotc.util.{SourcePosition, SrcPos}
 import dotty.tools.dotc.report
 
-import org.scalajs.ir.{Position, Names => jsNames, Trees => js, Types => jstpe}
-import org.scalajs.ir.Names.DefaultModuleID
-import org.scalajs.ir.OriginalName.NoOriginalName
-import org.scalajs.ir.Position.NoPosition
-import org.scalajs.ir.Trees.OptimizerHints
+import dotty.tools.sjs.ir.{Position, Names => jsNames, Trees => js, Types => jstpe}
+import dotty.tools.sjs.ir.Names.DefaultModuleID
+import dotty.tools.sjs.ir.OriginalName.NoOriginalName
+import dotty.tools.sjs.ir.Position.NoPosition
+import dotty.tools.sjs.ir.Trees.OptimizerHints
 
 import dotty.tools.dotc.transform.sjs.JSExportUtils._
 import dotty.tools.dotc.transform.sjs.JSSymUtils._
@@ -924,7 +924,7 @@ final class JSExportsGen(jsCodeGen: JSCodeGen)(using Context) {
         InstanceOfTypeTest(tpe.tycon.typeSymbol.typeRef)
 
       case _ =>
-        import org.scalajs.ir.Names
+        import dotty.tools.sjs.ir.Names
 
         (toIRType(tpe): @unchecked) match {
           case jstpe.AnyType => NoTypeTest
diff --git a/tests/pos-with-compiler-cc/backend/sjs/JSPositions.scala b/tests/pos-with-compiler-cc/backend/sjs/JSPositions.scala
index 2fd007165952..620e76ab4bab 100644
--- a/tests/pos-with-compiler-cc/backend/sjs/JSPositions.scala
+++ b/tests/pos-with-compiler-cc/backend/sjs/JSPositions.scala
@@ -13,7 +13,7 @@ import dotty.tools.dotc.report
 import dotty.tools.dotc.util.{SourceFile, SourcePosition}
 import dotty.tools.dotc.util.Spans.Span
 
-import org.scalajs.ir
+import dotty.tools.sjs.ir
 
 /** Conversion utilities from dotty Positions to IR Positions. */
 class JSPositions()(using Context) {

From 54ddb427898fa1a245a4bed320c113b518ca6081 Mon Sep 17 00:00:00 2001
From: Jamie Thompson <bishbashboshjt@gmail.com>
Date: Mon, 14 Oct 2024 17:43:32 +0200
Subject: [PATCH 11/39] add demonstration of plugin adjusting positions

---
 .../BootstrappedOnlyCompilationTests.scala    |  8 ++-
 .../run/scriptWrapper/Framework_1.scala       |  3 +
 .../scriptWrapper/LineNumberPlugin_1.scala    | 68 +++++++++++++++++++
 tests/plugins/run/scriptWrapper/Test_3.scala  | 25 +++++++
 tests/plugins/run/scriptWrapper/foo_2.scala   | 18 +++++
 .../run/scriptWrapper/foo_original_2.scala    |  8 +++
 .../run/scriptWrapper/plugin.properties       |  1 +
 7 files changed, 129 insertions(+), 2 deletions(-)
 create mode 100644 tests/plugins/run/scriptWrapper/Framework_1.scala
 create mode 100644 tests/plugins/run/scriptWrapper/LineNumberPlugin_1.scala
 create mode 100644 tests/plugins/run/scriptWrapper/Test_3.scala
 create mode 100644 tests/plugins/run/scriptWrapper/foo_2.scala
 create mode 100644 tests/plugins/run/scriptWrapper/foo_original_2.scala
 create mode 100644 tests/plugins/run/scriptWrapper/plugin.properties

diff --git a/compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala b/compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala
index a40c1ec1e5b2..5cd4f837b823 100644
--- a/compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala
+++ b/compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala
@@ -193,7 +193,7 @@ class BootstrappedOnlyCompilationTests {
 
     // 1. hack with absolute path for -Xplugin
     // 2. copy `pluginFile` to destination
-    def compileFilesInDir(dir: String): CompilationTest = {
+    def compileFilesInDir(dir: String, run: Boolean = false): CompilationTest = {
       val outDir = defaultOutputDir + "testPlugins/"
       val sourceDir = new java.io.File(dir)
 
@@ -201,7 +201,10 @@ class BootstrappedOnlyCompilationTests {
       val targets = dirs.map { dir =>
         val compileDir = createOutputDirsForDir(dir, sourceDir, outDir)
         Files.copy(dir.toPath.resolve(pluginFile), compileDir.toPath.resolve(pluginFile), StandardCopyOption.REPLACE_EXISTING)
-        val flags = TestFlags(withCompilerClasspath, noCheckOptions).and("-Xplugin:" + compileDir.getAbsolutePath)
+        val flags = {
+          val base = TestFlags(withCompilerClasspath, noCheckOptions).and("-Xplugin:" + compileDir.getAbsolutePath)
+          if run then base.withRunClasspath(withCompilerClasspath) else base
+        }
         SeparateCompilationSource("testPlugins", dir, flags, compileDir)
       }
 
@@ -210,6 +213,7 @@ class BootstrappedOnlyCompilationTests {
 
     compileFilesInDir("tests/plugins/neg").checkExpectedErrors()
     compileDir("tests/plugins/custom/analyzer", withCompilerOptions.and("-Yretain-trees")).checkCompile()
+    compileFilesInDir("tests/plugins/run", run = true).checkRuns()
   }
 }
 
diff --git a/tests/plugins/run/scriptWrapper/Framework_1.scala b/tests/plugins/run/scriptWrapper/Framework_1.scala
new file mode 100644
index 000000000000..c8a15de8342b
--- /dev/null
+++ b/tests/plugins/run/scriptWrapper/Framework_1.scala
@@ -0,0 +1,3 @@
+package framework
+
+class entrypoint extends scala.annotation.Annotation
diff --git a/tests/plugins/run/scriptWrapper/LineNumberPlugin_1.scala b/tests/plugins/run/scriptWrapper/LineNumberPlugin_1.scala
new file mode 100644
index 000000000000..888d5f95838d
--- /dev/null
+++ b/tests/plugins/run/scriptWrapper/LineNumberPlugin_1.scala
@@ -0,0 +1,68 @@
+package scriptWrapper
+
+import dotty.tools.dotc.*
+import core.*
+import Contexts.Context
+import Contexts.ctx
+import plugins.*
+import ast.tpd
+import util.SourceFile
+
+class LineNumberPlugin extends StandardPlugin {
+  val name: String = "linenumbers"
+  val description: String = "adjusts line numbers of script files"
+
+  override def initialize(options: List[String])(using Context): List[PluginPhase] = FixLineNumbers() :: Nil
+}
+
+// Loosely follows Mill linenumbers plugin (scan for marker with "original" source, adjust line numbers to match)
+class FixLineNumbers extends PluginPhase {
+
+  val codeMarker = "//USER_CODE_HERE"
+
+  def phaseName: String = "fixLineNumbers"
+  override def runsAfter: Set[String] = Set("posttyper")
+  override def runsBefore: Set[String] = Set("pickler")
+
+  override def transformUnit(tree: tpd.Tree)(using Context): tpd.Tree = {
+    val sourceContent = ctx.source.content()
+    val lines = new String(sourceContent).linesWithSeparators.toVector
+    val codeMarkerLine = lines.indexWhere(_.startsWith(codeMarker))
+
+    if codeMarkerLine < 0 then
+      tree
+    else
+      val adjustedFile = lines.collectFirst {
+        case s"//USER_SRC_FILE:./$file" => file.trim
+      }.getOrElse("<unknown>")
+
+      val adjustedSrc = ctx.source.file.container.lookupName(adjustedFile, directory = false) match
+        case null =>
+          report.error(s"could not find file $adjustedFile", tree.sourcePos)
+          return tree
+        case file =>
+          SourceFile(file, scala.io.Codec.UTF8)
+
+      val userCodeOffset = ctx.source.lineToOffset(codeMarkerLine + 1) // lines.take(codeMarkerLine).map(_.length).sum
+      val lineMapper = LineMapper(codeMarkerLine, userCodeOffset, adjustedSrc)
+      lineMapper.transform(tree)
+  }
+
+}
+
+class LineMapper(markerLine: Int, userCodeOffset: Int, adjustedSrc: SourceFile) extends tpd.TreeMapWithPreciseStatContexts() {
+
+  override def transform(tree: tpd.Tree)(using Context): tpd.Tree = {
+    val tree0 = super.transform(tree)
+    val pos = tree0.sourcePos
+    if pos.exists && pos.start >= userCodeOffset then
+      val tree1 = tree0.cloneIn(adjustedSrc).withSpan(pos.span.shift(-userCodeOffset))
+      // if tree1.show.toString == "???" then
+      //   val pos1 = tree1.sourcePos
+      //   sys.error(s"rewrote ??? at ${pos1.source}:${pos1.line + 1}:${pos1.column + 1} (sourced from ${markerLine + 2})")
+      tree1
+    else
+      tree0
+  }
+
+}
diff --git a/tests/plugins/run/scriptWrapper/Test_3.scala b/tests/plugins/run/scriptWrapper/Test_3.scala
new file mode 100644
index 000000000000..341af27ee433
--- /dev/null
+++ b/tests/plugins/run/scriptWrapper/Test_3.scala
@@ -0,0 +1,25 @@
+@main def Test: Unit = {
+  val mainCls = Class.forName("foo_sc")
+  val mainMethod = mainCls.getMethod("main", classOf[Array[String]])
+  val stackTrace: Array[String] = {
+    try
+      mainMethod.invoke(null, Array.empty[String])
+      sys.error("Expected an exception")
+    catch
+      case e: java.lang.reflect.InvocationTargetException =>
+        val cause = e.getCause
+        if cause != null then
+          cause.getStackTrace.map(_.toString)
+        else
+          throw e
+  }
+
+  val expected = Set(
+    "foo_sc$.getRandom(foo_2.scala:3)", // adjusted line number (11 -> 3)
+    "foo_sc$.brokenRandom(foo_2.scala:5)", // adjusted line number (13 -> 5)
+    "foo_sc$.run(foo_2.scala:8)", // adjusted line number (16 -> 8)
+  )
+
+  val missing = expected -- stackTrace
+  assert(missing.isEmpty, s"Missing: $missing")
+}
diff --git a/tests/plugins/run/scriptWrapper/foo_2.scala b/tests/plugins/run/scriptWrapper/foo_2.scala
new file mode 100644
index 000000000000..02e3f034e757
--- /dev/null
+++ b/tests/plugins/run/scriptWrapper/foo_2.scala
@@ -0,0 +1,18 @@
+// generated code
+// script: foo.sc
+object foo_sc {
+def main(args: Array[String]): Unit = {
+  run // assume some macro generates this by scanning for @entrypoint
+}
+//USER_SRC_FILE:./foo_original_2.scala
+//USER_CODE_HERE
+import framework.*
+
+def getRandom: Int = brokenRandom // LINE 3;
+
+def brokenRandom: Int = ??? // LINE 5;
+
+@entrypoint
+def run = println("Hello, here is a random number: " + getRandom) // LINE 8;
+//END_USER_CODE_HERE
+}
diff --git a/tests/plugins/run/scriptWrapper/foo_original_2.scala b/tests/plugins/run/scriptWrapper/foo_original_2.scala
new file mode 100644
index 000000000000..162ddd1724a1
--- /dev/null
+++ b/tests/plugins/run/scriptWrapper/foo_original_2.scala
@@ -0,0 +1,8 @@
+import framework.*
+
+def getRandom: Int = brokenRandom // LINE 3;
+
+def brokenRandom: Int = ??? // LINE 5;
+
+@entrypoint
+def run = println("Hello, here is a random number: " + getRandom) // LINE 8;
diff --git a/tests/plugins/run/scriptWrapper/plugin.properties b/tests/plugins/run/scriptWrapper/plugin.properties
new file mode 100644
index 000000000000..f1fc6067e611
--- /dev/null
+++ b/tests/plugins/run/scriptWrapper/plugin.properties
@@ -0,0 +1 @@
+pluginClass=scriptWrapper.LineNumberPlugin

From 44ecf4beb7b7b748ccf58d2bb3329ec87eb61d2b Mon Sep 17 00:00:00 2001
From: Jamie Thompson <bishbashboshjt@gmail.com>
Date: Mon, 14 Oct 2024 18:12:41 +0200
Subject: [PATCH 12/39] dont introduce new API

---
 compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala | 2 +-
 compiler/src/dotty/tools/dotc/util/SourcePosition.scala     | 5 -----
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala b/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala
index 38e5617fc3d7..4f4caf36d92a 100644
--- a/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala
+++ b/compiler/src/dotty/tools/backend/jvm/BCodeSkelBuilder.scala
@@ -626,7 +626,7 @@ trait BCodeSkelBuilder extends BCodeHelpers {
         val nr =
           val sourcePos = tree.sourcePos
           (
-            if sourcePos.exists then sourcePos.finalPosition.line
+            if sourcePos.exists then sourcePos.source.positionInUltimateSource(sourcePos).line
             else ctx.source.offsetToLine(tree.span.point) // fallback
           ) + 1
 
diff --git a/compiler/src/dotty/tools/dotc/util/SourcePosition.scala b/compiler/src/dotty/tools/dotc/util/SourcePosition.scala
index 384d2f1fb2f3..a7358755043c 100644
--- a/compiler/src/dotty/tools/dotc/util/SourcePosition.scala
+++ b/compiler/src/dotty/tools/dotc/util/SourcePosition.scala
@@ -79,11 +79,6 @@ extends SrcPos, interfaces.SourcePosition, Showable {
     rec(this)
   }
 
-  def finalPosition: SourcePosition = {
-    source.positionInUltimateSource(this)
-  }
-
-
   override def toString: String =
     s"${if (source.exists) source.file.toString else "(no source)"}:$span"
 

From b94160bceeec20950875644f17593f169208e07e Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Tue, 15 Oct 2024 16:47:43 +0200
Subject: [PATCH 13/39] Fix relative docs in `givens.md` (#21774)

Previously were referring to non-exisitng file in the outer directory.

[skip ci]
---
 docs/_docs/reference/contextual/givens.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/_docs/reference/contextual/givens.md b/docs/_docs/reference/contextual/givens.md
index 9c074da0da6e..2b360dfc7af0 100644
--- a/docs/_docs/reference/contextual/givens.md
+++ b/docs/_docs/reference/contextual/givens.md
@@ -87,7 +87,7 @@ time it is accessed. If the given is a mere alias to some immutable value, the g
 
 ## Syntax
 
-Here is the full syntax for given instances. Some of these forms of givens are explained in a separate page: [Other Forms of Givens](../more-givens.md).
+Here is the full syntax for given instances. Some of these forms of givens are explained in a separate page: [Other Forms of Givens](./more-givens.md).
 
 ```ebnf
 TmplDef           ::=  ... | 'given' GivenDef
@@ -113,4 +113,4 @@ A given instance starts with the reserved keyword `given`, which is followed by
     - A _structural given_ implements one or more class constructors with a
       list of member definitions in a template body.
 
-**Note** Parts of the given syntax have changed in Scala 3.6. The original syntax from Scala 3.0 on is described in a separate page [Previous Given Syntax](../previous-givens.md). The original syntax is still supported for now but will be deprecated and phased out over time.
+**Note** Parts of the given syntax have changed in Scala 3.6. The original syntax from Scala 3.0 on is described in a separate page [Previous Given Syntax](./previous-givens.md). The original syntax is still supported for now but will be deprecated and phased out over time.

From e546f0779905e8a2ca8df68139b808ec89213008 Mon Sep 17 00:00:00 2001
From: Matt Bovel <matthieu@bovel.net>
Date: Tue, 15 Oct 2024 16:58:30 +0200
Subject: [PATCH 14/39] Add so68877939.scala

---
 tests/pos/so68877939.scala | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
 create mode 100644 tests/pos/so68877939.scala

diff --git a/tests/pos/so68877939.scala b/tests/pos/so68877939.scala
new file mode 100644
index 000000000000..41c5ee8ac659
--- /dev/null
+++ b/tests/pos/so68877939.scala
@@ -0,0 +1,15 @@
+abstract class Quantity[A <: Quantity[A]]
+sealed trait UnitOfMeasure[A <: Quantity[A]]
+
+class Time extends Quantity[Time]
+object Minutes extends UnitOfMeasure[Time]
+
+class PowerRamp extends Quantity[PowerRamp]
+object KilowattsPerHour extends UnitOfMeasure[PowerRamp]
+
+type Test[X <: UnitOfMeasure[?]] = X match
+  case UnitOfMeasure[t] => t
+
+@main def main =
+  summon[Test[Minutes.type] =:= Time]
+  summon[Test[KilowattsPerHour.type] =:= PowerRamp]

From f6bfa0afddd35bc965e5930f1e050e293cf9dfe1 Mon Sep 17 00:00:00 2001
From: Seth Tisue <seth@tisue.net>
Date: Tue, 15 Oct 2024 11:09:50 -0700
Subject: [PATCH 15/39] Scala 2.13.15 (was .14) (#21648)

Co-authored-by: Wojciech Mazur <wmazur@virtuslab.com>
---
 .../community-projects/scala-collection-compat         |  2 +-
 community-build/community-projects/stdLib213           |  2 +-
 .../src/scala/dotty/communitybuild/projects.scala      |  4 ++--
 project/Build.scala                                    | 10 +++++-----
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/community-build/community-projects/scala-collection-compat b/community-build/community-projects/scala-collection-compat
index 2bf3fea914b2..c9d3a8b160a3 160000
--- a/community-build/community-projects/scala-collection-compat
+++ b/community-build/community-projects/scala-collection-compat
@@ -1 +1 @@
-Subproject commit 2bf3fea914b2f13e4805b3e7b519bdf0e595e4c9
+Subproject commit c9d3a8b160a35c9915816dd84a1063e18db4a84a
diff --git a/community-build/community-projects/stdLib213 b/community-build/community-projects/stdLib213
index fcc67cd56c67..b6f70d2347f2 160000
--- a/community-build/community-projects/stdLib213
+++ b/community-build/community-projects/stdLib213
@@ -1 +1 @@
-Subproject commit fcc67cd56c67851bf31019ec25ccb09d08b9561b
+Subproject commit b6f70d2347f2857695e5c0fe544b0f921544b02a
diff --git a/community-build/src/scala/dotty/communitybuild/projects.scala b/community-build/src/scala/dotty/communitybuild/projects.scala
index e8d6c3d2894d..31c1bb95743c 100644
--- a/community-build/src/scala/dotty/communitybuild/projects.scala
+++ b/community-build/src/scala/dotty/communitybuild/projects.scala
@@ -476,8 +476,8 @@ 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(
diff --git a/project/Build.scala b/project/Build.scala
index 9b4e24f37c75..5b04d623f122 100644
--- a/project/Build.scala
+++ b/project/Build.scala
@@ -149,8 +149,8 @@ object Build {
    *  scala-library.
    */
   def stdlibVersion(implicit mode: Mode): String = mode match {
-    case NonBootstrapped => "2.13.14"
-    case Bootstrapped => "2.13.14"
+    case NonBootstrapped => "2.13.15"
+    case Bootstrapped => "2.13.15"
   }
 
   /** Version of the scala-library for which we will generate TASTy.
@@ -160,7 +160,7 @@ object Build {
    *  We can use nightly versions to tests the future compatibility in development.
    *  Nightly versions: https://scala-ci.typesafe.com/ui/native/scala-integration/org/scala-lang
    */
-  val stdlibBootstrappedVersion = "2.13.14"
+  val stdlibBootstrappedVersion = "2.13.15"
 
   val dottyOrganization = "org.scala-lang"
   val dottyGithubUrl = "https://github.com/scala/scala3"
@@ -1426,7 +1426,7 @@ object Build {
       BuildInfoPlugin.buildInfoDefaultSettings
 
   lazy val presentationCompilerSettings = {
-    val mtagsVersion = "1.3.4"
+    val mtagsVersion = "1.3.5"
     Seq(
       libraryDependencies ++= Seq(
         "org.lz4" % "lz4-java" % "1.8.0",
@@ -1436,7 +1436,7 @@ object Build {
           .exclude("org.eclipse.lsp4j","org.eclipse.lsp4j.jsonrpc"),
         "org.eclipse.lsp4j" % "org.eclipse.lsp4j" % "0.20.1",
       ),
-      libraryDependencies += ("org.scalameta" % "mtags-shared_2.13.14" % mtagsVersion % SourceDeps),
+      libraryDependencies += ("org.scalameta" % "mtags-shared_2.13.15" % mtagsVersion % SourceDeps),
       ivyConfigurations += SourceDeps.hide,
       transitiveClassifiers := Seq("sources"),
       scalacOptions ++= Seq("-source", "3.3"), // To avoid fatal migration warnings

From af9ee8ea8f232e08d5248d088fae00949f608f36 Mon Sep 17 00:00:00 2001
From: Georgi Krastev <joro.kr.21@gmail.com>
Date: Wed, 16 Oct 2024 10:40:02 +0200
Subject: [PATCH 16/39] Fix tupleTypeFromSeq for XXL tuples

---
 library/src/scala/quoted/Expr.scala |  2 +-
 tests/pos/i21779/Macro_1.scala      | 36 +++++++++++++++++++++++++++++
 tests/pos/i21779/Test_2.scala       |  3 +++
 3 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 tests/pos/i21779/Macro_1.scala
 create mode 100644 tests/pos/i21779/Test_2.scala

diff --git a/library/src/scala/quoted/Expr.scala b/library/src/scala/quoted/Expr.scala
index f1045e5bdaca..d1385a0193d6 100644
--- a/library/src/scala/quoted/Expr.scala
+++ b/library/src/scala/quoted/Expr.scala
@@ -256,7 +256,7 @@ object Expr {
   private def tupleTypeFromSeq(seq: Seq[Expr[Any]])(using Quotes): quotes.reflect.TypeRepr =
     import quotes.reflect.*
     val consRef = Symbol.classSymbol("scala.*:").typeRef
-    seq.foldLeft(TypeRepr.of[EmptyTuple]) { (ts, expr) =>
+    seq.foldRight(TypeRepr.of[EmptyTuple]) { (expr, ts) =>
       AppliedType(consRef, expr.asTerm.tpe :: ts :: Nil)
     }
 
diff --git a/tests/pos/i21779/Macro_1.scala b/tests/pos/i21779/Macro_1.scala
new file mode 100644
index 000000000000..d40f5e28de5e
--- /dev/null
+++ b/tests/pos/i21779/Macro_1.scala
@@ -0,0 +1,36 @@
+import scala.quoted.*
+
+object Macro:
+  transparent inline def tupleXxl: Tuple =
+    ${tupleXxlExpr}
+
+  def tupleXxlExpr(using Quotes) =
+    import quotes.reflect.*
+    Expr.ofTupleFromSeq(
+      Seq(
+        Expr("a"),
+        Expr(2),
+        Expr(3),
+        Expr(4),
+        Expr(5),
+        Expr(6),
+        Expr(7),
+        Expr(8),
+        Expr(9),
+        Expr(10),
+        Expr(11),
+        Expr(12),
+        Expr(13),
+        Expr(14),
+        Expr(15),
+        Expr(16),
+        Expr(17),
+        Expr(18),
+        Expr(19),
+        Expr(20),
+        Expr(21),
+        Expr(22),
+        Expr(23),
+      )
+    )
+
diff --git a/tests/pos/i21779/Test_2.scala b/tests/pos/i21779/Test_2.scala
new file mode 100644
index 000000000000..e614e3ca564d
--- /dev/null
+++ b/tests/pos/i21779/Test_2.scala
@@ -0,0 +1,3 @@
+object Test:
+  val result: ("a", 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23) =
+    Macro.tupleXxl

From 5a68b16cc6632504ceed509772ef0e4aad8d5025 Mon Sep 17 00:00:00 2001
From: Kacper Korban <kacper.f.korban@gmail.com>
Date: Wed, 16 Oct 2024 14:20:13 +0200
Subject: [PATCH 17/39] Add a docs page for betterFors experimental feature

---
 .../reference/experimental/better-fors.md     | 79 +++++++++++++++++++
 1 file changed, 79 insertions(+)
 create mode 100644 docs/_docs/reference/experimental/better-fors.md

diff --git a/docs/_docs/reference/experimental/better-fors.md b/docs/_docs/reference/experimental/better-fors.md
new file mode 100644
index 000000000000..7add425caf51
--- /dev/null
+++ b/docs/_docs/reference/experimental/better-fors.md
@@ -0,0 +1,79 @@
+---
+layout: doc-page
+title: "Better fors"
+nightlyOf: https://docs.scala-lang.org/scala3/reference/experimental/better-fors.html
+---
+
+The `betterFors` language extension improves the usability of `for`-comprehensions.
+
+The extension is enabled by the language import `import scala.language.experimental.betterFors` or by setting the command line option `-language:experimental.betterFors`.
+
+The biggest user facing change is the new ability to start `for`-comprehensions with with aliases. This means that the following previously invalid code is now valid:
+
+```scala
+for
+  as = List(1, 2, 3)
+  bs = List(4, 5, 6)
+  a <- as
+  b <- bs
+yield a + b
+```
+
+The desugaring of this code is the same as if the aliases were introduced with `val`:
+
+```scala
+val as = List(1, 2, 3)
+val bs = List(4, 5, 6)
+for
+  a <- as
+  b <- bs
+yield a + b
+```
+
+Additionally this extension changes the way `for`-comprehensions are desugared. The desugaring is now done in a more intuitive way and the desugared code can be more efficient, because it avoids some unnecessary method calls. There are two main changes in the desugaring:
+
+1. **Simpler Desugaring for Pure Aliases**:
+    When an alias is not followed by a guard, the desugaring is simplified. The last generator and the aliases don't have to be wrapped in a tuple, and instead the aliases are simply introduced as local variables in a block with the next generator.
+    **Current Desugaring**:
+      ```scala
+      for {
+        a <- doSth(arg)
+        b = a
+      } yield a + b
+      ```
+      Desugars to:
+      ```scala
+      doSth(arg).map { a =>
+        val b = a
+        (a, b)
+      }.map { case (a, b) =>
+        a + b
+      }
+      ```
+    **New Desugaring**:
+      ```scala
+      doSth(arg).map { a =>
+        val b = a
+        a + b
+      }
+      ```
+    This change makes the desugaring more intuitive and avoids unnecessary `map` calls, when an alias is not followed by a guard.
+
+2. **Avoiding Redundant `map` Calls**:
+    When the result of the `for`-comprehension is the same expression as the last generator pattern, the desugaring avoids an unnecessary `map` call. but th eequality of the last pattern and the result has to be able to be checked syntactically, so it is either a variable or a tuple of variables.
+    **Current Desugaring**:
+      ```scala
+      for {
+        a <- List(1, 2, 3)
+      } yield a
+      ```
+      Desugars to:
+      ```scala
+      List(1, 2, 3).map(a => a)
+      ```
+    **New Desugaring**:
+      ```scala
+      List(1, 2, 3)
+      ```
+
+For more details on the desugaring scheme see the comment in [`Desugar.scala#makeFor`](https://github.com/scala/scala3/blob/main/compiler/src/dotty/tools/dotc/ast/Desugar.scala#L1928).
\ No newline at end of file

From a4387dbc8383f76a7be66b03c4598fcc16741727 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Pa=C5=82ka?= <prolativus@gmail.com>
Date: Wed, 16 Oct 2024 15:55:59 +0200
Subject: [PATCH 18/39] Apply implicit conversion from derived Conversion
 instance defined as implicit rather than given

---
 .../dotty/tools/dotc/typer/Implicits.scala    |  2 +-
 tests/pos/i21757.scala                        | 33 +++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 tests/pos/i21757.scala

diff --git a/compiler/src/dotty/tools/dotc/typer/Implicits.scala b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
index 3c2f025dc095..c42b196b8dfb 100644
--- a/compiler/src/dotty/tools/dotc/typer/Implicits.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
@@ -1176,7 +1176,7 @@ trait Implicits:
             case _ => info.derivesFrom(defn.ConversionClass)
           def tryConversion(using Context) = {
             val untpdConv =
-              if ref.symbol.is(Given) && producesConversion(ref.symbol.info) then
+              if ref.symbol.isOneOf(GivenOrImplicit) && producesConversion(ref.symbol.info) then
                 untpd.Select(
                   untpd.TypedSplice(
                     adapt(generated,
diff --git a/tests/pos/i21757.scala b/tests/pos/i21757.scala
new file mode 100644
index 000000000000..7595540c4b58
--- /dev/null
+++ b/tests/pos/i21757.scala
@@ -0,0 +1,33 @@
+object ConversionChain {
+
+  class X(val value: Int)
+
+  class Y(val x: X)
+
+  class Z(val y: Y)
+
+  trait Conv[A, B] extends Conversion[A, B]
+
+  given xy: Conv[X, Y] = { (x: X) => new Y(x) }
+
+  given yz: Conv[Y, Z] = { (y: Y) => new Z(y) }
+
+  object ConvUtils {
+    implicit def hypotheticalSyllogism[A, B, C]( // implicit def instead of given
+        using
+        ab: Conv[A, B],
+        bc: Conv[B, C]
+    ): Conv[A, C] = {
+
+      new Conv[A, C] {
+        def apply(a: A): C = bc(ab(a))
+      }
+    }
+  }
+  import ConvUtils.hypotheticalSyllogism
+
+  def test(): Unit = {
+    val x = new X(42)
+    val z: Z = x
+  }
+}

From 7f70ed3a3d100b697d18b541a0ec09ca788b826d Mon Sep 17 00:00:00 2001
From: Jan Chyb <jan.chyb.99@gmail.com>
Date: Wed, 16 Oct 2024 18:42:12 +0200
Subject: [PATCH 19/39] Add the macro type-print test to an
 run-macros-scala2-library-tasty.blacklist

---
 compiler/test/dotc/run-macros-scala2-library-tasty.blacklist | 1 +
 1 file changed, 1 insertion(+)

diff --git a/compiler/test/dotc/run-macros-scala2-library-tasty.blacklist b/compiler/test/dotc/run-macros-scala2-library-tasty.blacklist
index 63a6e2cee345..6fdfccf7646c 100644
--- a/compiler/test/dotc/run-macros-scala2-library-tasty.blacklist
+++ b/compiler/test/dotc/run-macros-scala2-library-tasty.blacklist
@@ -2,3 +2,4 @@
 tasty-extractors-1
 tasty-extractors-2
 tasty-extractors-types
+type-print

From 6d9ee4dcc21a1f6bd644883c099d57f6c7fbbeab Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Thu, 17 Oct 2024 19:29:59 +0200
Subject: [PATCH 20/39] Fix CI workflows for publishing releases.  (#21789)

Reuse SDKs generated in `build-sdk-package` job.
Store .sha256 for each of the files, instead of creating sha256.txt with
shas for the reach directory to ease validation
---
 .github/workflows/ci.yaml | 280 ++++++++++++++++++++++++++------------
 1 file changed, 194 insertions(+), 86 deletions(-)

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 95a6ed24df13..5baa8d3dea81 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -729,7 +729,7 @@ jobs:
         - ${{ github.workspace }}/../../cache/sbt:/root/.sbt
         - ${{ github.workspace }}/../../cache/ivy:/root/.ivy2/cache
         - ${{ github.workspace }}/../../cache/general:/root/.cache
-    needs: [test_non_bootstrapped, test, mima, community_build_a, community_build_b, community_build_c, test_sbt, test_java8]
+    needs: [test_non_bootstrapped, test, mima, community_build_a, community_build_b, community_build_c, test_sbt, test_java8, build-sdk-package]
     if: "github.event_name == 'push'
          && startsWith(github.event.ref, 'refs/tags/')"
 
@@ -765,31 +765,51 @@ jobs:
       # Extract the release tag
       - name: Extract the release tag
         run : echo "RELEASE_TAG=${GITHUB_REF#*refs/tags/}" >> $GITHUB_ENV
-      # BUILD THE SDKs
-      - name: Build and pack the SDK (universal)
-        run : |
-          ./project/scripts/sbt dist/packArchive
-          sha256sum dist/target/scala3-* > dist/target/sha256sum.txt
-      - name: Build and pack the SDK (linux x86-64)
-        run : |
-          ./project/scripts/sbt dist-linux-x86_64/packArchive
-          sha256sum dist/linux-x86_64/target/scala3-* > dist/linux-x86_64/target/sha256sum.txt
-      - name: Build and pack the SDK (linux aarch64)
-        run : |
-          ./project/scripts/sbt dist-linux-aarch64/packArchive
-          sha256sum dist/linux-aarch64/target/scala3-* > dist/linux-aarch64/target/sha256sum.txt
-      - name: Build and pack the SDK (mac x86-64)
-        run : |
-          ./project/scripts/sbt dist-mac-x86_64/packArchive
-          sha256sum dist/mac-x86_64/target/scala3-* > dist/mac-x86_64/target/sha256sum.txt
-      - name: Build and pack the SDK (mac aarch64)
-        run : |
-          ./project/scripts/sbt dist-mac-aarch64/packArchive
-          sha256sum dist/mac-aarch64/target/scala3-* > dist/mac-aarch64/target/sha256sum.txt
-      - name: Build and pack the SDK (win x86-64)
+
+      - name: Prepare the SDKs
         run : |
-          ./project/scripts/sbt dist-win-x86_64/packArchive
-          sha256sum dist/win-x86_64/target/scala3-* > dist/win-x86_64/target/sha256sum.txt
+          function prepareSDK() {
+            distroSuffix="$1"
+            artifactId="$2"
+            artifactName="scala3-${{ env.RELEASE_TAG }}${distroSuffix}"
+
+            downloadedArchive="./artifact.zip"
+            if [[ -f "${downloadedArchive}" ]]; then
+              rm "${downloadedArchive}"
+            fi
+
+            # Download previously prepared SDK bundle
+            curl -L \
+              -H "Authorization: token ${{secrets.GITHUB_TOKEN}}" \
+              -H "Accept: application/vnd.github+json" \
+              -o "${downloadedArchive}" \
+              --retry 5 --retry-delay 10 --retry-connrefused \
+              --max-time 600 --connect-timeout 60  \
+              https://api.github.com/repos/scala/scala3/actions/artifacts/${artifactId}/zip
+
+            # Repackage content of .zip to .tar.gz and prepare digest
+            tmpDir="./archive-tmp-dir"
+            if [[ -d "${tmpDir}" ]]; then
+              rm -r "${tmpDir}"
+            fi
+            mkdir "${tmpDir}"
+            unzip "${downloadedArchive}" -d "${tmpDir}"
+
+            mv "${downloadedArchive}" "./${artifactName}.zip"
+            tar -czf "${artifactName}.tar.gz" -C "${tmpDir}" .
+
+            # Caluclate SHA for each of archive files
+            for file in "${artifactName}.zip" "${artifactName}.tar.gz"; do
+              sha256sum "${file}" > "${file}.sha256"
+            done
+          }
+          prepareSDK "" ${{needs.build-sdk-package.outputs.universal-id}}
+          prepareSDK "-aarch64-pc-linux"     ${{needs.build-sdk-package.outputs.linux-aarch64-id}}
+          prepareSDK "-x86_64-pc-linux"      ${{needs.build-sdk-package.outputs.linux-x86_64-id}}
+          prepareSDK "-aarch64-apple-darwin" ${{needs.build-sdk-package.outputs.mac-aarch64-id}}
+          prepareSDK "-x86_64-apple-darwin"  ${{needs.build-sdk-package.outputs.mac-x86_64-id}}
+          prepareSDK "-x86_64-pc-win32"      ${{needs.build-sdk-package.outputs.win-x86_64-id}}
+
       # Create the GitHub release
       - name: Create GitHub Release
         id: create_gh_release
@@ -803,179 +823,267 @@ jobs:
           draft: true
           prerelease: ${{ contains(env.RELEASE_TAG, '-') }}
 
-      - name: Upload zip archive to GitHub Release (universal)
+      # The following steps are generated using template:
+      # def template(distribution: String, suffix: String) =
+      #   def upload(kind: String, path: String, contentType: String) =
+      #     s"""- name: Upload $kind to GitHub Release ($distribution)
+      #         uses: actions/upload-release-asset@v1
+      #         env:
+      #           GITHUB_TOKEN: $${{ secrets.GITHUB_TOKEN }}
+      #         with:
+      #           upload_url: $${{ steps.create_gh_release.outputs.upload_url }}
+      #           asset_path: ./${path}
+      #           asset_name: ${path}
+      #           asset_content_type: ${contentType}"""
+      #   val filename = s"scala3-$${{ env.RELEASE_TAG }}${suffix}"
+      #   s"""
+      #       # $distribution
+      #       ${upload("zip archive", s"$filename.zip", "application/zip")}
+      #       ${upload("zip archive SHA", s"$filename.zip.sha256", "text/plain")}
+      #       ${upload("tar.gz archive", s"$filename.tar.gz", "application/gzip")}
+      #       ${upload("tar.gz archive SHA", s"$filename.tar.gz.sha256", "text/plain")}
+      # """
+
+      # @main def gen =
+      #   Seq(
+      #     template("Universal", ""),
+      #     template("Linux x86-64", "-x86_64-pc-linux"),
+      #     template("Linux aarch64", "-aarch64-pc-linux"),
+      #     template("Mac x86-64", "-x86_64-apple-darwin"),
+      #     template("Mac aarch64", "-aarcb64-apple-darwin"),
+      #     template("Windows x86_64", "-x86_64-pc-win32")
+      #   ).foreach(println)
+      # Universal
+      - name: Upload zip archive to GitHub Release (Universal)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/target/scala3-${{ env.RELEASE_TAG }}.zip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}.zip
           asset_name: scala3-${{ env.RELEASE_TAG }}.zip
           asset_content_type: application/zip
-      - name: Upload tar.gz archive to GitHub Release (universal)
+      - name: Upload zip archive SHA to GitHub Release (Universal)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/target/scala3-${{ env.RELEASE_TAG }}.tar.gz
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}.zip.sha256
+          asset_content_type: text/plain
+      - name: Upload tar.gz archive to GitHub Release (Universal)
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}.tar.gz
           asset_name: scala3-${{ env.RELEASE_TAG }}.tar.gz
           asset_content_type: application/gzip
+      - name: Upload tar.gz archive SHA to GitHub Release (Universal)
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}.tar.gz.sha256
+          asset_content_type: text/plain
+
 
-      - name: Upload zip archive to GitHub Release (linux x86-64)
+      # Linux x86-64
+      - name: Upload zip archive to GitHub Release (Linux x86-64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/linux-x86_64/target/scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.zip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.zip
           asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.zip
           asset_content_type: application/zip
-      - name: Upload tar.gz archive to GitHub Release (linux x86-64)
+      - name: Upload zip archive SHA to GitHub Release (Linux x86-64)
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.zip.sha256
+          asset_content_type: text/plain
+      - name: Upload tar.gz archive to GitHub Release (Linux x86-64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/linux-x86_64/target/scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.tar.gz
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.tar.gz
           asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.tar.gz
           asset_content_type: application/gzip
+      - name: Upload tar.gz archive SHA to GitHub Release (Linux x86-64)
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-linux.tar.gz.sha256
+          asset_content_type: text/plain
+
 
-      - name: Upload zip archive to GitHub Release (linux aarch64)
+      # Linux aarch64
+      - name: Upload zip archive to GitHub Release (Linux aarch64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/linux-aarch64/target/scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.zip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.zip
           asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.zip
           asset_content_type: application/zip
-      - name: Upload tar.gz archive to GitHub Release (linux aarch64)
+      - name: Upload zip archive SHA to GitHub Release (Linux aarch64)
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.zip.sha256
+          asset_content_type: text/plain
+      - name: Upload tar.gz archive to GitHub Release (Linux aarch64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/linux-aarch64/target/scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.tar.gz
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.tar.gz
           asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.tar.gz
           asset_content_type: application/gzip
+      - name: Upload tar.gz archive SHA to GitHub Release (Linux aarch64)
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-pc-linux.tar.gz.sha256
+          asset_content_type: text/plain
 
-      - name: Upload zip archive to GitHub Release (mac x86-64)
+
+      # Mac x86-64
+      - name: Upload zip archive to GitHub Release (Mac x86-64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/mac-x86_64/target/scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.zip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.zip
           asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.zip
           asset_content_type: application/zip
-      - name: Upload tar.gz archive to GitHub Release (mac x86-64)
+      - name: Upload zip archive SHA to GitHub Release (Mac x86-64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/mac-x86_64/target/scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.tar.gz
-          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.tar.gz
-          asset_content_type: application/gzip
-
-      - name: Upload zip archive to GitHub Release (mac aarch64)
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.zip.sha256
+          asset_content_type: text/plain
+      - name: Upload tar.gz archive to GitHub Release (Mac x86-64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/mac-aarch64/target/scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.zip
-          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.zip
-          asset_content_type: application/zip
-      - name: Upload tar.gz archive to GitHub Release (mac aarch64)
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.tar.gz
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.tar.gz
+          asset_content_type: application/gzip
+      - name: Upload tar.gz archive SHA to GitHub Release (Mac x86-64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/mac-aarch64/target/scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.tar.gz
-          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.tar.gz
-          asset_content_type: application/gzip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-apple-darwin.tar.gz.sha256
+          asset_content_type: text/plain
+
 
-      - name: Upload zip archive to GitHub Release (win x86-64)
+      # Mac aarch64
+      - name: Upload zip archive to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/win-x86_64/target/scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.zip
-          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.zip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip
           asset_content_type: application/zip
-      - name: Upload tar.gz archive to GitHub Release (win x86-64)
+      - name: Upload zip archive SHA to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/win-x86_64/target/scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.tar.gz
-          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.tar.gz
-          asset_content_type: application/gzip
-
-
-      - name: Upload SHA256 sum of the release artefacts to GitHub Release (universal)
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip.sha256
+          asset_content_type: text/plain
+      - name: Upload tar.gz archive to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/target/sha256sum.txt
-          asset_name: sha256sum.txt
-          asset_content_type: text/plain
-
-      - name: Upload SHA256 sum of the release artefacts to GitHub Release (linux x86-64)
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz
+          asset_content_type: application/gzip
+      - name: Upload tar.gz archive SHA to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/linux-x86_64/target/sha256sum.txt
-          asset_name: sha256sum-x86_64-pc-linux.txt
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz.sha256
           asset_content_type: text/plain
 
-      - name: Upload SHA256 sum of the release artefacts to GitHub Release (linux aarch64)
+
+      # Windows x86_64
+      - name: Upload zip archive to GitHub Release (Windows x86_64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/linux-aarch64/target/sha256sum.txt
-          asset_name: sha256sum-aarch64-pc-linux.txt
-          asset_content_type: text/plain
-
-      - name: Upload SHA256 sum of the release artefacts to GitHub Release (mac x86-64)
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.zip
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.zip
+          asset_content_type: application/zip
+      - name: Upload zip archive SHA to GitHub Release (Windows x86_64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/mac-x86_64/target/sha256sum.txt
-          asset_name: sha256sum-x86_64-apple-darwin.txt
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.zip.sha256
           asset_content_type: text/plain
-
-      - name: Upload SHA256 sum of the release artefacts to GitHub Release (mac aarch64)
+      - name: Upload tar.gz archive to GitHub Release (Windows x86_64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/mac-aarch64/target/sha256sum.txt
-          asset_name: sha256sum-aarch64-apple-darwin.txt
-          asset_content_type: text/plain
-
-      - name: Upload SHA256 sum of the release artefacts to GitHub Release (win x86-64)
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.tar.gz
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.tar.gz
+          asset_content_type: application/gzip
+      - name: Upload tar.gz archive SHA to GitHub Release (Windows x86_64)
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./dist/win-x86_64/target/sha256sum.txt
-          asset_name: sha256sum-x86_64-pc-win32.txt
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-x86_64-pc-win32.tar.gz.sha256
           asset_content_type: text/plain
 
       - name: Publish Release

From a0db7c1ebf476cfdd1c0396b0ba1bd622e2d36b4 Mon Sep 17 00:00:00 2001
From: noti0na1 <noti0na1@users.noreply.github.com>
Date: Thu, 26 Sep 2024 21:06:14 +0200
Subject: [PATCH 21/39] Allow opaque type def in repl

---
 compiler/src/dotty/tools/dotc/parsing/Parsers.scala | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
index 5a3be6505715..4172914c0fb0 100644
--- a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
+++ b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
@@ -4696,6 +4696,8 @@ object Parsers {
           stats += closure(in.offset, Location.InBlock, modifiers(BitSet(IMPLICIT)))
         else if isIdent(nme.extension) && followingIsExtension() then
           stats += extension()
+        else if ctx.mode.is(Mode.Interactive) && isDefIntro(localModifierTokens) then
+          stats +++= localDef(in.offset)
         else if isDefIntro(localModifierTokens, excludedSoftModifiers = Set(nme.`opaque`)) then
           stats +++= localDef(in.offset)
         else

From 16ebbea25de6074ead7388c09434758c424700a6 Mon Sep 17 00:00:00 2001
From: noti0na1 <noti0na1@users.noreply.github.com>
Date: Fri, 4 Oct 2024 03:42:03 +0200
Subject: [PATCH 22/39] Only allow opaque type def at outermost

---
 compiler/src/dotty/tools/dotc/parsing/Parsers.scala | 4 ++--
 compiler/src/dotty/tools/repl/ParseResult.scala     | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
index 4172914c0fb0..6d35aeb9ac82 100644
--- a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
+++ b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
@@ -4684,7 +4684,7 @@ object Parsers {
      *                 | Expr1
      *                 |
      */
-    def blockStatSeq(): List[Tree] = checkNoEscapingPlaceholders {
+    def blockStatSeq(outermost: Boolean = false): List[Tree] = checkNoEscapingPlaceholders {
       val stats = new ListBuffer[Tree]
       while
         var empty = false
@@ -4696,7 +4696,7 @@ object Parsers {
           stats += closure(in.offset, Location.InBlock, modifiers(BitSet(IMPLICIT)))
         else if isIdent(nme.extension) && followingIsExtension() then
           stats += extension()
-        else if ctx.mode.is(Mode.Interactive) && isDefIntro(localModifierTokens) then
+        else if outermost && ctx.mode.is(Mode.Interactive) && isDefIntro(localModifierTokens) then
           stats +++= localDef(in.offset)
         else if isDefIntro(localModifierTokens, excludedSoftModifiers = Set(nme.`opaque`)) then
           stats +++= localDef(in.offset)
diff --git a/compiler/src/dotty/tools/repl/ParseResult.scala b/compiler/src/dotty/tools/repl/ParseResult.scala
index b9139343bca1..24a624173050 100644
--- a/compiler/src/dotty/tools/repl/ParseResult.scala
+++ b/compiler/src/dotty/tools/repl/ParseResult.scala
@@ -122,7 +122,7 @@ object ParseResult {
 
   private def parseStats(using Context): List[untpd.Tree] = {
     val parser = new Parser(ctx.source)
-    val stats = parser.blockStatSeq()
+    val stats = parser.blockStatSeq(outermost = true)
     parser.accept(Tokens.EOF)
     stats
   }

From 634d9b79beae0e4098ef93affd25a5d761268e14 Mon Sep 17 00:00:00 2001
From: noti0na1 <noti0na1@users.noreply.github.com>
Date: Fri, 11 Oct 2024 05:50:21 +0200
Subject: [PATCH 23/39] Add REPL test

---
 .../dotty/tools/repl/ReplCompilerTests.scala  | 28 ++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/compiler/test/dotty/tools/repl/ReplCompilerTests.scala b/compiler/test/dotty/tools/repl/ReplCompilerTests.scala
index 374f53dbd011..221eb8acb9de 100644
--- a/compiler/test/dotty/tools/repl/ReplCompilerTests.scala
+++ b/compiler/test/dotty/tools/repl/ReplCompilerTests.scala
@@ -462,10 +462,36 @@ class ReplCompilerTests extends ReplTest:
     .andThen:
       run("0") // check for crash
       val last = lines()
-      println(last)
       assertTrue(last(0), last(0) == ("Options incompatible with repl will be ignored: -Ybest-effort, -Ywith-best-effort-tasty"))
       assertTrue(last(1), last(1) == ("val res0: Int = 0"))
 
+  @Test def `i9879`: Unit = initially:
+    run {
+      """|opaque type A = Int; def getA: A = 0
+         |object Wrapper { opaque type A = Int; def getA: A = 1 }
+         |val x = getA
+         |val y = Wrapper.getA""".stripMargin
+    }
+    val expected = List(
+      "def getA: A",
+      "// defined object Wrapper",
+      "val x: A = 0",
+      "val y: Wrapper.A = 1"
+    )
+    assertEquals(expected, lines())
+
+  @Test def `i9879b`: Unit = initially:
+    run {
+      """|def test =
+         |  type A = Int
+         |  opaque type B = String
+         |  object Wrapper { opaque type C = Int }
+         |  ()""".stripMargin
+    }
+    val all = lines()
+    assertEquals(6, all.length)
+    assertTrue(all.head.startsWith("-- [E103] Syntax Error"))
+    assertTrue(all.exists(_.trim().startsWith("|  Illegal start of statement: this modifier is not allowed here")))
 
 object ReplCompilerTests:
 

From 3a98a1cd3efd52fdb7e92f03d7d9ddc7f8ed3282 Mon Sep 17 00:00:00 2001
From: noti0na1 <noti0na1@users.noreply.github.com>
Date: Fri, 18 Oct 2024 10:44:58 +0200
Subject: [PATCH 24/39] Remove extra if

---
 compiler/src/dotty/tools/dotc/parsing/Parsers.scala | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
index 6d35aeb9ac82..6390d8d32d3f 100644
--- a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
+++ b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
@@ -4696,9 +4696,11 @@ object Parsers {
           stats += closure(in.offset, Location.InBlock, modifiers(BitSet(IMPLICIT)))
         else if isIdent(nme.extension) && followingIsExtension() then
           stats += extension()
-        else if outermost && ctx.mode.is(Mode.Interactive) && isDefIntro(localModifierTokens) then
-          stats +++= localDef(in.offset)
-        else if isDefIntro(localModifierTokens, excludedSoftModifiers = Set(nme.`opaque`)) then
+        else if isDefIntro(localModifierTokens,
+            excludedSoftModifiers =
+              // Allow opaque definitions at outermost level in REPL.
+              if outermost && ctx.mode.is(Mode.Interactive)
+              then Set.empty else Set(nme.`opaque`)) then
           stats +++= localDef(in.offset)
         else
           empty = true

From dd47185afa1a2ef0e0fa6f99ed7c40d0e87b49ee Mon Sep 17 00:00:00 2001
From: Hamza Remmal <hamza@remmal.dev>
Date: Fri, 18 Oct 2024 12:22:18 +0200
Subject: [PATCH 25/39] Add zip and unzip to the CI

---
 .github/Dockerfile        |  3 ++-
 .github/workflows/ci.yaml | 26 +++++++++++++-------------
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/.github/Dockerfile b/.github/Dockerfile
index d56ec6a59f2d..59d46fd169d9 100644
--- a/.github/Dockerfile
+++ b/.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
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 95a6ed24df13..8d91e22c8ee8 100644
--- a/.github/workflows/ci.yaml
+++ b/.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
@@ -160,7 +160,7 @@ jobs:
   test_scala2_library_tasty:
     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
@@ -287,7 +287,7 @@ 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
@@ -338,7 +338,7 @@ 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
@@ -395,7 +395,7 @@ 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
@@ -452,7 +452,7 @@ 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
@@ -509,7 +509,7 @@ 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
@@ -554,7 +554,7 @@ 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
@@ -614,7 +614,7 @@ 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
@@ -677,7 +677,7 @@ 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
@@ -723,7 +723,7 @@ 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
@@ -985,7 +985,7 @@ 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.

From 3161e06b3509d93d39ae05f52f95ea407e53fb84 Mon Sep 17 00:00:00 2001
From: Kacper Korban <kacper.f.korban@gmail.com>
Date: Fri, 18 Oct 2024 13:14:05 +0200
Subject: [PATCH 26/39] Add batter-fors doc link to sidebar

---
 docs/sidebar.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/sidebar.yml b/docs/sidebar.yml
index f12e732f1c6f..74aee3dfc668 100644
--- a/docs/sidebar.yml
+++ b/docs/sidebar.yml
@@ -162,6 +162,7 @@ subsection:
           - page: reference/experimental/modularity.md
           - page: reference/experimental/typeclasses.md
           - page: reference/experimental/runtimeChecked.md
+          - page: reference/experimental/better-fors.md
       - page: reference/syntax.md
       - title: Language Versions
         index: reference/language-versions/language-versions.md

From 6d040c517682856fad4b4969e08c4eb405da551e Mon Sep 17 00:00:00 2001
From: Kacper Korban <kacper.f.korban@gmail.com>
Date: Fri, 18 Oct 2024 17:47:33 +0200
Subject: [PATCH 27/39] fix: Drop copied parent refinements before generating
 bytecode (#21733)

Refinements are copied over from parents, because they might be needed
for tracked members that should have more specific types in the child.
These members are generated without an implementation and should not be
used in runtime.

possible fix for #21213

---------

Co-authored-by: Dale Wijnand <dale.wijnand@gmail.com>
Co-authored-by: Matt Bovel <matthieu@bovel.net>
---
 compiler/src/dotty/tools/dotc/Compiler.scala  |  1 +
 .../transform/DropParentRefinements.scala     | 35 +++++++++++++++++++
 .../dotty/tools/dotc/transform/Getters.scala  |  2 +-
 .../src/dotty/tools/dotc/typer/Namer.scala    |  8 ++---
 .../src/dotty/tools/dotc/typer/Typer.scala    |  5 ++-
 .../transformed/lazy-vals-legacy.check        |  2 +-
 .../printing/transformed/lazy-vals-new.check  |  2 +-
 tests/run/i21213-min.check                    |  1 +
 tests/run/i21213-min.scala                    |  9 +++++
 tests/run/i21213.check                        |  1 +
 tests/run/i21213.scala                        | 10 ++++++
 11 files changed, 68 insertions(+), 8 deletions(-)
 create mode 100644 compiler/src/dotty/tools/dotc/transform/DropParentRefinements.scala
 create mode 100644 tests/run/i21213-min.check
 create mode 100644 tests/run/i21213-min.scala
 create mode 100644 tests/run/i21213.check
 create mode 100644 tests/run/i21213.scala

diff --git a/compiler/src/dotty/tools/dotc/Compiler.scala b/compiler/src/dotty/tools/dotc/Compiler.scala
index 9b130e7d7804..f9503e4f8554 100644
--- a/compiler/src/dotty/tools/dotc/Compiler.scala
+++ b/compiler/src/dotty/tools/dotc/Compiler.scala
@@ -132,6 +132,7 @@ class Compiler {
          new ElimStaticThis,         // Replace `this` references to static objects by global identifiers
          new CountOuterAccesses) ::  // Identify outer accessors that can be dropped
     List(new DropOuterAccessors,     // Drop unused outer accessors
+         new DropParentRefinements,  // Drop parent refinements from a template
          new CheckNoSuperThis,       // Check that supercalls don't contain references to `this`
          new Flatten,                // Lift all inner classes to package scope
          new TransformWildcards,     // Replace wildcards with default values
diff --git a/compiler/src/dotty/tools/dotc/transform/DropParentRefinements.scala b/compiler/src/dotty/tools/dotc/transform/DropParentRefinements.scala
new file mode 100644
index 000000000000..1960568dc505
--- /dev/null
+++ b/compiler/src/dotty/tools/dotc/transform/DropParentRefinements.scala
@@ -0,0 +1,35 @@
+package dotty.tools.dotc.transform
+
+import dotty.tools.dotc.transform.MegaPhase.MiniPhase
+import dotty.tools.dotc.ast.tpd
+import dotty.tools.dotc.core.Contexts.Context
+import dotty.tools.dotc.core.DenotTransformers.IdentityDenotTransformer
+import dotty.tools.dotc.typer.Typer
+
+object DropParentRefinements:
+  val name: String = "dropParentRefinements"
+  val description: String = "drop parent refinements from a template"
+
+/** Drop parent refinements from a template, as they are generated without
+  * an implementation. These refinements are unusally required for tracked
+  * members with more specific types.
+  */
+class DropParentRefinements extends MiniPhase with IdentityDenotTransformer:
+  thisPhase =>
+  import tpd.*
+
+  override def phaseName: String = DropParentRefinements.name
+
+  override def description: String = DropParentRefinements.description
+
+  override def runsAfterGroupsOf: Set[String] = Set(CountOuterAccesses.name)
+
+  override def changesMembers: Boolean = true // the phase drops parent refinements
+
+  override def transformTemplate(tree: tpd.Template)(using Context): tpd.Tree =
+    val newBody = tree.body.filter(!_.hasAttachment(Typer.RefinementFromParent))
+    tree.body.foreach { member =>
+      if member.hasAttachment(Typer.RefinementFromParent) then
+        member.symbol.dropAfter(thisPhase)
+    }
+    cpy.Template(tree)(body = newBody)
diff --git a/compiler/src/dotty/tools/dotc/transform/Getters.scala b/compiler/src/dotty/tools/dotc/transform/Getters.scala
index 43289209d146..a58dffa04223 100644
--- a/compiler/src/dotty/tools/dotc/transform/Getters.scala
+++ b/compiler/src/dotty/tools/dotc/transform/Getters.scala
@@ -103,7 +103,7 @@ class Getters extends MiniPhase with SymTransformer { thisPhase =>
   override def transformValDef(tree: ValDef)(using Context): Tree =
     val sym = tree.symbol
     if !sym.is(Method) then return tree
-    val getterDef = DefDef(sym.asTerm, tree.rhs).withSpan(tree.span)
+    val getterDef = DefDef(sym.asTerm, tree.rhs).withSpan(tree.span).withAttachmentsFrom(tree)
     if !sym.is(Mutable) then return getterDef
     ensureSetter(sym.asTerm)
     if !newSetters.contains(sym.setter) then return getterDef
diff --git a/compiler/src/dotty/tools/dotc/typer/Namer.scala b/compiler/src/dotty/tools/dotc/typer/Namer.scala
index 6167db62fbe0..0849e57b8c7d 100644
--- a/compiler/src/dotty/tools/dotc/typer/Namer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Namer.scala
@@ -877,16 +877,16 @@ class Namer { typer: Typer =>
     protected def addAnnotations(sym: Symbol): Unit = original match {
       case original: untpd.MemberDef =>
         lazy val annotCtx = annotContext(original, sym)
-        original.setMods: 
+        original.setMods:
           original.mods.withAnnotations :
-            original.mods.annotations.mapConserve: annotTree =>  
+            original.mods.annotations.mapConserve: annotTree =>
               val cls = typedAheadAnnotationClass(annotTree)(using annotCtx)
               if (cls eq sym)
                 report.error(em"An annotation class cannot be annotated with iself", annotTree.srcPos)
                 annotTree
               else
-                val ann = 
-                  if cls.is(JavaDefined) then Checking.checkNamedArgumentForJavaAnnotation(annotTree, cls.asClass) 
+                val ann =
+                  if cls.is(JavaDefined) then Checking.checkNamedArgumentForJavaAnnotation(annotTree, cls.asClass)
                   else annotTree
                 val ann1 = Annotation.deferred(cls)(typedAheadExpr(ann)(using annotCtx))
                 sym.addAnnotation(ann1)
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index ce72aac596c0..89ce01231fed 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -78,6 +78,9 @@ object Typer {
   /** An attachment for GADT constraints that were inferred for a pattern. */
   val InferredGadtConstraints = new Property.StickyKey[core.GadtConstraint]
 
+  /** Indicates that a definition was copied over from the parent refinements */
+  val RefinementFromParent = new Property.StickyKey[Unit]
+
   /** An attachment on a Select node with an `apply` field indicating that the `apply`
    *  was inserted by the Typer.
    */
@@ -3071,7 +3074,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
             ( if sym.isType then TypeDef(sym.asType)
               else if sym.is(Method) then DefDef(sym.asTerm)
               else ValDef(sym.asTerm)
-            ).withSpan(impl.span.startPos)
+            ).withSpan(impl.span.startPos).withAttachment(RefinementFromParent, ())
           body ++ refinements
         case None =>
           body
diff --git a/tests/printing/transformed/lazy-vals-legacy.check b/tests/printing/transformed/lazy-vals-legacy.check
index 2768a89b9c9e..d8969619d2b2 100644
--- a/tests/printing/transformed/lazy-vals-legacy.check
+++ b/tests/printing/transformed/lazy-vals-legacy.check
@@ -1,4 +1,4 @@
-[[syntax trees at end of MegaPhase{dropOuterAccessors, checkNoSuperThis, flatten, transformWildcards, moveStatic, expandPrivate, restoreScopes, selectStatic, Collect entry points, collectSuperCalls, repeatableAnnotations}]] // tests/printing/transformed/lazy-vals-legacy.scala
+[[syntax trees at end of MegaPhase{dropOuterAccessors, dropParentRefinements, checkNoSuperThis, flatten, transformWildcards, moveStatic, expandPrivate, restoreScopes, selectStatic, Collect entry points, collectSuperCalls, repeatableAnnotations}]] // tests/printing/transformed/lazy-vals-legacy.scala
 package <empty> {
   @SourceFile("tests/printing/transformed/lazy-vals-legacy.scala") final module
     class A extends Object {
diff --git a/tests/printing/transformed/lazy-vals-new.check b/tests/printing/transformed/lazy-vals-new.check
index 05471e5677dc..8997f0109e79 100644
--- a/tests/printing/transformed/lazy-vals-new.check
+++ b/tests/printing/transformed/lazy-vals-new.check
@@ -1,4 +1,4 @@
-[[syntax trees at end of MegaPhase{dropOuterAccessors, checkNoSuperThis, flatten, transformWildcards, moveStatic, expandPrivate, restoreScopes, selectStatic, Collect entry points, collectSuperCalls, repeatableAnnotations}]] // tests/printing/transformed/lazy-vals-new.scala
+[[syntax trees at end of MegaPhase{dropOuterAccessors, dropParentRefinements, checkNoSuperThis, flatten, transformWildcards, moveStatic, expandPrivate, restoreScopes, selectStatic, Collect entry points, collectSuperCalls, repeatableAnnotations}]] // tests/printing/transformed/lazy-vals-new.scala
 package <empty> {
   @SourceFile("tests/printing/transformed/lazy-vals-new.scala") final module
     class A extends Object {
diff --git a/tests/run/i21213-min.check b/tests/run/i21213-min.check
new file mode 100644
index 000000000000..5716ca5987cb
--- /dev/null
+++ b/tests/run/i21213-min.check
@@ -0,0 +1 @@
+bar
diff --git a/tests/run/i21213-min.scala b/tests/run/i21213-min.scala
new file mode 100644
index 000000000000..0f6aa6f8ddd5
--- /dev/null
+++ b/tests/run/i21213-min.scala
@@ -0,0 +1,9 @@
+import scala.language.experimental.modularity
+import scala.language.future
+
+sealed abstract class Foo(tracked val discriminator: String)
+class Bar extends Foo("bar")
+
+val bar: Foo = Bar()
+object Test extends App:
+  println(bar.discriminator)
diff --git a/tests/run/i21213.check b/tests/run/i21213.check
new file mode 100644
index 000000000000..5716ca5987cb
--- /dev/null
+++ b/tests/run/i21213.check
@@ -0,0 +1 @@
+bar
diff --git a/tests/run/i21213.scala b/tests/run/i21213.scala
new file mode 100644
index 000000000000..ec609afd7da3
--- /dev/null
+++ b/tests/run/i21213.scala
@@ -0,0 +1,10 @@
+import scala.language.experimental.modularity
+import scala.language.future
+
+enum Foo(tracked val discriminator: String):
+  case Bar() extends Foo("bar")
+  case Baz() extends Foo("baz")
+
+val bar: Foo = Foo.Bar()
+object Test extends App:
+  println(bar.discriminator)

From 34f1c546b968f2d14443e48e268a93c3f19923d1 Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Sat, 19 Oct 2024 20:04:40 +0200
Subject: [PATCH 28/39] Fix and future-proof the CI release scripts (#21810)

- Forward-ports changes to `publish_release` CI job from `release-3.6.1`
branch.
* Fix building SDK archives, don't use `build-sdk-packages` job that
produced artifacts in SNAPSHOT version
  * Fix typos introduced in template (forward port from `release-3.6.0`)
- Detect and check version used to publish artifacts:
* For release builds ensure that `version` is always matching tag used
to trigger CI job
* For nightly builds ensure that `version` is following the expected
pattern
---
 .github/workflows/ci.yaml | 89 +++++++++++++++++++++------------------
 1 file changed, 47 insertions(+), 42 deletions(-)

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index d64c02c55042..72f4f5559fd7 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -663,6 +663,13 @@ jobs:
           echo "This build version: $ver"
           echo "THISBUILD_VERSION=$ver" >> $GITHUB_ENV
 
+      - name: Check is version matching pattern
+        run: |
+          if ! grep -Eo "3\.[0-9]+\.[0-9]+-RC[0-9]+-bin-[0-9]{8}-[a-zA-Z0-9]{7}-NIGHTLY" <<< "${{ env.THISBUILD_VERSION }}"; then
+            echo "Version used by compiler to publish nightly release does not match expected pattern"
+            exit 1
+          fi
+
       - name: Check whether not yet published
         id: not_yet_published
         continue-on-error: true
@@ -766,49 +773,47 @@ jobs:
       - name: Extract the release tag
         run : echo "RELEASE_TAG=${GITHUB_REF#*refs/tags/}" >> $GITHUB_ENV
 
+      - 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 the SDKs
+        shell: bash
         run : |
-          function prepareSDK() {
+          prepareSDK() {
             distroSuffix="$1"
-            artifactId="$2"
+            sbtProject="$2"
+            distDir="$3"
+
+            # Build binaries
+            ./project/scripts/sbt "${sbtProject}/Universal/stage"
+
+            outputPath="${distDir}/target/universal/stage"
             artifactName="scala3-${{ env.RELEASE_TAG }}${distroSuffix}"
+            zipArchive="${artifactName}.zip"
+            tarGzArchive="${artifactName}.tar.gz"
 
-            downloadedArchive="./artifact.zip"
-            if [[ -f "${downloadedArchive}" ]]; then
-              rm "${downloadedArchive}"
-            fi
-
-            # Download previously prepared SDK bundle
-            curl -L \
-              -H "Authorization: token ${{secrets.GITHUB_TOKEN}}" \
-              -H "Accept: application/vnd.github+json" \
-              -o "${downloadedArchive}" \
-              --retry 5 --retry-delay 10 --retry-connrefused \
-              --max-time 600 --connect-timeout 60  \
-              https://api.github.com/repos/scala/scala3/actions/artifacts/${artifactId}/zip
-
-            # Repackage content of .zip to .tar.gz and prepare digest
-            tmpDir="./archive-tmp-dir"
-            if [[ -d "${tmpDir}" ]]; then
-              rm -r "${tmpDir}"
-            fi
-            mkdir "${tmpDir}"
-            unzip "${downloadedArchive}" -d "${tmpDir}"
-
-            mv "${downloadedArchive}" "./${artifactName}.zip"
-            tar -czf "${artifactName}.tar.gz" -C "${tmpDir}" .
+            cwd=$(pwd)
+            (cd $outputPath && zip -r ${zipArchive} . && mv ${zipArchive} "${cwd}/")
+            tar -czf ${tarGzArchive} -C "$outputPath" .
 
             # Caluclate SHA for each of archive files
-            for file in "${artifactName}.zip" "${artifactName}.tar.gz"; do
+            for file in "${zipArchive}" "${tarGzArchive}"; do
               sha256sum "${file}" > "${file}.sha256"
             done
           }
-          prepareSDK "" ${{needs.build-sdk-package.outputs.universal-id}}
-          prepareSDK "-aarch64-pc-linux"     ${{needs.build-sdk-package.outputs.linux-aarch64-id}}
-          prepareSDK "-x86_64-pc-linux"      ${{needs.build-sdk-package.outputs.linux-x86_64-id}}
-          prepareSDK "-aarch64-apple-darwin" ${{needs.build-sdk-package.outputs.mac-aarch64-id}}
-          prepareSDK "-x86_64-apple-darwin"  ${{needs.build-sdk-package.outputs.mac-x86_64-id}}
-          prepareSDK "-x86_64-pc-win32"      ${{needs.build-sdk-package.outputs.win-x86_64-id}}
+          prepareSDK ""                      "dist"               "./dist/"
+          prepareSDK "-aarch64-pc-linux"     "dist-linux-aarch64" "./dist/linux-aarch64/"
+          prepareSDK "-x86_64-pc-linux"      "dist-linux-x86_64"  "./dist/linux-x86_64/"
+          prepareSDK "-aarch64-apple-darwin" "dist-mac-aarch64"   "./dist/mac-aarch64/"
+          prepareSDK "-x86_64-apple-darwin"  "dist-mac-x86_64"    "./dist/mac-x86_64/"
+          prepareSDK "-x86_64-pc-win32"      "dist-win-x86_64"    "./dist/win-x86_64/"
 
       # Create the GitHub release
       - name: Create GitHub Release
@@ -850,7 +855,7 @@ jobs:
       #     template("Linux x86-64", "-x86_64-pc-linux"),
       #     template("Linux aarch64", "-aarch64-pc-linux"),
       #     template("Mac x86-64", "-x86_64-apple-darwin"),
-      #     template("Mac aarch64", "-aarcb64-apple-darwin"),
+      #     template("Mac aarch64", "-aarch64-apple-darwin"),
       #     template("Windows x86_64", "-x86_64-pc-win32")
       #   ).foreach(println)
       # Universal
@@ -1016,8 +1021,8 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip
-          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.zip
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.zip
           asset_content_type: application/zip
       - name: Upload zip archive SHA to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
@@ -1025,8 +1030,8 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip.sha256
-          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.zip.sha256
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.zip.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.zip.sha256
           asset_content_type: text/plain
       - name: Upload tar.gz archive to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
@@ -1034,8 +1039,8 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz
-          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.tar.gz
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.tar.gz
           asset_content_type: application/gzip
       - name: Upload tar.gz archive SHA to GitHub Release (Mac aarch64)
         uses: actions/upload-release-asset@v1
@@ -1043,8 +1048,8 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           upload_url: ${{ steps.create_gh_release.outputs.upload_url }}
-          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz.sha256
-          asset_name: scala3-${{ env.RELEASE_TAG }}-aarcb64-apple-darwin.tar.gz.sha256
+          asset_path: ./scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.tar.gz.sha256
+          asset_name: scala3-${{ env.RELEASE_TAG }}-aarch64-apple-darwin.tar.gz.sha256
           asset_content_type: text/plain
 
 

From bcbdb5ef52c93dd34b93294a9774fdd57d9fb2aa Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Sat, 19 Oct 2024 20:04:59 +0200
Subject: [PATCH 29/39] Prepare development setup for 3.6.2 (#21811)

- Set baseVersiont o 3.6.2
- Set referenceVersion to 3.6.1 and move `src/boostrapped` files to
`src`
- Set mimaPreviousArtifactVersion to 3.6.1 (exception from the rule due
to broken 3.6.0 release)
---
 .../{src-bootstrapped => src}/scala/NamedTuple.scala   |  0
 project/Build.scala                                    | 10 ++++++----
 2 files changed, 6 insertions(+), 4 deletions(-)
 rename library/{src-bootstrapped => src}/scala/NamedTuple.scala (100%)

diff --git a/library/src-bootstrapped/scala/NamedTuple.scala b/library/src/scala/NamedTuple.scala
similarity index 100%
rename from library/src-bootstrapped/scala/NamedTuple.scala
rename to library/src/scala/NamedTuple.scala
diff --git a/project/Build.scala b/project/Build.scala
index 5b04d623f122..3433053629f7 100644
--- a/project/Build.scala
+++ b/project/Build.scala
@@ -91,11 +91,12 @@ object DottyJSPlugin extends AutoPlugin {
 object Build {
   import ScaladocConfigs._
 
-  val referenceVersion = "3.5.2-RC1"
+  val referenceVersion = "3.6.1"
 
-  val baseVersion = "3.6.1"
+  val baseVersion = "3.6.2"
   // Will be required by some automation later
-  val prereleaseVersion = s"$baseVersion-RC1"
+  // TODO: Introduce automation and handling for RC versions before 3.6.2-RC1
+  // val prereleaseVersion = s"$baseVersion-RC1"
 
   // LTS or Next
   val versionLine = "Next"
@@ -113,8 +114,9 @@ object Build {
    *  For a baseVersion `3.M.P` the mimaPreviousDottyVersion should be set to:
    *   - `3.M.0`     if `P > 0`
    *   - `3.(M-1).0` if `P = 0`
+   *  3.6.1 is an exception from this rule - 3.6.0 was a broken release
    */
-  val mimaPreviousDottyVersion = "3.5.0"
+  val mimaPreviousDottyVersion = "3.6.1"
 
   /** LTS version against which we check binary compatibility.
    *

From 40956e15df0048d76d8f4e5bebac920743e00cdc Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Sat, 19 Oct 2024 23:10:00 +0200
Subject: [PATCH 30/39] Downgrade referenceVersion to 3.6.0 and add notes how
 referenceVersion should be set (#21813)

The main branch should always use a compiler with experimental tasty -
it's required for non_boostrapped tests to pass. It's required because
we cannot consume stable version of tasty from it's experimental
subversion (it's assumed that stable version > experimental version for
the same major/minor pair)

We pick 3.6.0 (released by mistake during 3.6.0-RC1) because that's the
last non-stable version pushed to Maven. Typically we would use the last
RC version

[test_non_bootstrapped]
---
 project/Build.scala | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/project/Build.scala b/project/Build.scala
index 3433053629f7..464ba4a86411 100644
--- a/project/Build.scala
+++ b/project/Build.scala
@@ -91,7 +91,13 @@ object DottyJSPlugin extends AutoPlugin {
 object Build {
   import ScaladocConfigs._
 
-  val referenceVersion = "3.6.1"
+  /** Version of the Scala compiler used to build the artifacts.
+   *  Reference version should track the latest version pushed to Maven:
+   *  - In main branch it should be the last RC version (using experimental TASTy required for non-bootstrapped tests)
+   *  - In release branch it should be the last stable release
+   *  3.6.0-RC1 was released as 3.6.0 - it's having and experimental TASTy version
+   */
+  val referenceVersion = "3.6.0"
 
   val baseVersion = "3.6.2"
   // Will be required by some automation later

From 654bc6c889251a9bb895d077ac43850ab234ffe4 Mon Sep 17 00:00:00 2001
From: Jentsch <d@jentsch.berlin>
Date: Sat, 19 Oct 2024 22:19:46 +0000
Subject: [PATCH 31/39] Fix scaladoc graph highlight background color in dark
 mode

Also fix two typos
---
 scaladoc/resources/dotty_res/scripts/ux.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/scaladoc/resources/dotty_res/scripts/ux.js b/scaladoc/resources/dotty_res/scripts/ux.js
index 7b875fbcef8e..97f9bf14939d 100644
--- a/scaladoc/resources/dotty_res/scripts/ux.js
+++ b/scaladoc/resources/dotty_res/scripts/ux.js
@@ -10,7 +10,7 @@ const attrsToCopy = [
 
 /**
  * @typedef {Object} SavedPageState
- * @property {Strign} mainDiv
+ * @property {String} mainDiv
  * @property {String} leftColumn
  * @property {String} title
  * @property {Record<string, string>} attrs
@@ -322,7 +322,7 @@ function attachAllListeners() {
 
   if (location.hash) {
     var target = location.hash.substring(1);
-    // setting the 'expand' class on the top-level container causes undesireable styles
+    // setting the 'expand' class on the top-level container causes undesirable styles
     // to apply to the top-level docs, so we avoid this logic for that element.
     if (target != "container") {
       var selected = document.getElementById(location.hash.substring(1));
@@ -568,7 +568,7 @@ function showGraph() {
         .attr("offset", "30%");
       radialGradient
         .append("stop")
-        .attr("stop-color", "var(--background-default)")
+        .attr("stop-color", "var(--background-main)")
         .attr("offset", "100%");
 
       var inner = svg.append("g");

From 022b1ffa21631fb96e424942ba12b49f6996ec77 Mon Sep 17 00:00:00 2001
From: Hamza Remmal <hamza@remmal.dev>
Date: Sun, 20 Oct 2024 08:45:12 +0200
Subject: [PATCH 32/39] Use bash shell when using here-strings (#21817)

<img width="1032" alt="Screenshot 2024-10-20 at 07 14 49"
src="https://github.com/user-attachments/assets/321ba7ce-9fd2-413c-aec3-14215fbee786">


[positive](https://github.com/WojciechMazur/dotty/actions/runs/11416876799/job/31768568868)
test in #21810 also uses `bash` instead of `sh`

Closes #21815
---
 .github/workflows/ci.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 72f4f5559fd7..91086858c514 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -664,6 +664,7 @@ jobs:
           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"

From 959f68c1259aa12734432c990d71d3fa2d99427e Mon Sep 17 00:00:00 2001
From: Matt Bovel <matthieu@bovel.net>
Date: Mon, 21 Oct 2024 18:22:43 +0200
Subject: [PATCH 33/39] Warn when named tuples resemble assignments
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-Authored-By: Nicolas Stucki <3648029+nicolasstucki@users.noreply.github.com>
Co-Authored-By: Oliver Bračevac <bracevac@users.noreply.github.com>
---
 compiler/src/dotty/tools/dotc/ast/Desugar.scala          | 9 ++++++---
 .../src/dotty/tools/dotc/reporting/ErrorMessageID.scala  | 1 +
 compiler/src/dotty/tools/dotc/reporting/messages.scala   | 9 +++++++++
 tests/warn/21681.check                                   | 7 +++++++
 tests/warn/21681.scala                                   | 3 +++
 tests/warn/21770.check                                   | 7 +++++++
 tests/warn/21770.scala                                   | 5 +++++
 7 files changed, 38 insertions(+), 3 deletions(-)
 create mode 100644 tests/warn/21681.check
 create mode 100644 tests/warn/21681.scala
 create mode 100644 tests/warn/21770.check
 create mode 100644 tests/warn/21770.scala

diff --git a/compiler/src/dotty/tools/dotc/ast/Desugar.scala b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
index e1a6b97fc7d3..482210845fea 100644
--- a/compiler/src/dotty/tools/dotc/ast/Desugar.scala
+++ b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
@@ -1605,9 +1605,10 @@ object desugar {
 
   /** Translate tuple expressions
    *
-   *     ()             ==>   ()
-   *     (t)            ==>   t
-   *     (t1, ..., tN)  ==>   TupleN(t1, ..., tN)
+   *     ()                       ==>   ()
+   *     (t)                      ==>   t
+   *     (t1, ..., tN)            ==>   TupleN(t1, ..., tN)
+   *     (n1 = t1, ..., nN = tN)  ==>   NamedTuple.build[(n1, ..., nN)]()(TupleN(t1, ..., tN))
    */
   def tuple(tree: Tuple, pt: Type)(using Context): Tree =
     var elems = checkWellFormedTupleElems(tree.trees)
@@ -1638,6 +1639,8 @@ object desugar {
       if ctx.mode.is(Mode.Type) then
         AppliedTypeTree(ref(defn.NamedTupleTypeRef), namesTuple :: tup :: Nil)
       else
+        if names.length == 1 && ctx.scope.lookup(names.head).is(Flags.Mutable) then
+          report.migrationWarning(AmbiguousNamedTupleAssignment(names.head, elemValues.head), tree.srcPos)
         Apply(
           Apply(
             TypeApply(
diff --git a/compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala b/compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala
index db523c879ea2..6d0a85b3ef0f 100644
--- a/compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala
+++ b/compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala
@@ -216,6 +216,7 @@ enum ErrorMessageID(val isActive: Boolean = true) extends java.lang.Enum[ErrorMe
   case FinalLocalDefID // errorNumber: 200
   case NonNamedArgumentInJavaAnnotationID // errorNumber: 201
   case QuotedTypeMissingID // errorNumber: 202
+  case AmbiguousNamedTupleAssignmentID // errorNumber: 203
 
   def errorNumber = ordinal - 1
 
diff --git a/compiler/src/dotty/tools/dotc/reporting/messages.scala b/compiler/src/dotty/tools/dotc/reporting/messages.scala
index 97cd70113c2e..3b7fba1cb52d 100644
--- a/compiler/src/dotty/tools/dotc/reporting/messages.scala
+++ b/compiler/src/dotty/tools/dotc/reporting/messages.scala
@@ -3343,3 +3343,12 @@ final class QuotedTypeMissing(tpe: Type)(using Context) extends StagingMessage(Q
         |"""
 
 end QuotedTypeMissing
+
+final class AmbiguousNamedTupleAssignment(key: Name, value: untpd.Tree)(using Context) extends SyntaxMsg(AmbiguousNamedTupleAssignmentID):
+  override protected def msg(using Context): String =
+    i"""Ambiguous syntax: this is interpreted as a named tuple with one element,
+      |not as an assignment.
+      |
+      |To assign a value, use curly braces: `{${key} = ${value}}`."""
+  
+  override protected def explain(using Context): String = ""
diff --git a/tests/warn/21681.check b/tests/warn/21681.check
new file mode 100644
index 000000000000..e86ce4e36134
--- /dev/null
+++ b/tests/warn/21681.check
@@ -0,0 +1,7 @@
+-- [E203] Syntax Migration Warning: tests/warn/21681.scala:3:2 ---------------------------------------------------------
+3 |  (age = 29) // warn
+  |  ^^^^^^^^^^
+  |  Ambiguous syntax: this is interpreted as a named tuple with one element,
+  |  not as an assignment.
+  |
+  |  To assign a value, use curly braces: `{age = 29}`.
diff --git a/tests/warn/21681.scala b/tests/warn/21681.scala
new file mode 100644
index 000000000000..76a19c96e1cb
--- /dev/null
+++ b/tests/warn/21681.scala
@@ -0,0 +1,3 @@
+def main() =
+  var age: Int = 28
+  (age = 29) // warn
diff --git a/tests/warn/21770.check b/tests/warn/21770.check
new file mode 100644
index 000000000000..0899f11d6ca5
--- /dev/null
+++ b/tests/warn/21770.check
@@ -0,0 +1,7 @@
+-- [E203] Syntax Migration Warning: tests/warn/21770.scala:5:9 ---------------------------------------------------------
+5 |  f(i => (cache = Some(i))) // warn
+  |         ^^^^^^^^^^^^^^^^^
+  |         Ambiguous syntax: this is interpreted as a named tuple with one element,
+  |         not as an assignment.
+  |
+  |         To assign a value, use curly braces: `{cache = Some(i)}`.
diff --git a/tests/warn/21770.scala b/tests/warn/21770.scala
new file mode 100644
index 000000000000..9696a31d6ba8
--- /dev/null
+++ b/tests/warn/21770.scala
@@ -0,0 +1,5 @@
+def f(g: Int  => Unit) = g(0)
+
+def test = 
+  var cache: Option[Int] = None
+  f(i => (cache = Some(i))) // warn

From a00a806361666822c2a8098c2f45f8b93df15483 Mon Sep 17 00:00:00 2001
From: Matt Bovel <matthieu@bovel.net>
Date: Mon, 21 Oct 2024 19:51:53 +0200
Subject: [PATCH 34/39] Move AmbiguousNamedTupleAssignment check to Typer
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-Authored-By: Nicolas Stucki <3648029+nicolasstucki@users.noreply.github.com>
Co-Authored-By: Oliver Bračevac <bracevac@users.noreply.github.com>
---
 compiler/src/dotty/tools/dotc/ast/Desugar.scala |  2 --
 compiler/src/dotty/tools/dotc/typer/Typer.scala | 13 +++++++++++++
 tests/pos/21681d.scala                          | 16 ++++++++++++++++
 tests/warn/21681b.check                         |  7 +++++++
 tests/warn/21681b.scala                         |  3 +++
 5 files changed, 39 insertions(+), 2 deletions(-)
 create mode 100644 tests/pos/21681d.scala
 create mode 100644 tests/warn/21681b.check
 create mode 100644 tests/warn/21681b.scala

diff --git a/compiler/src/dotty/tools/dotc/ast/Desugar.scala b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
index 482210845fea..e66c71731b4f 100644
--- a/compiler/src/dotty/tools/dotc/ast/Desugar.scala
+++ b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
@@ -1639,8 +1639,6 @@ object desugar {
       if ctx.mode.is(Mode.Type) then
         AppliedTypeTree(ref(defn.NamedTupleTypeRef), namesTuple :: tup :: Nil)
       else
-        if names.length == 1 && ctx.scope.lookup(names.head).is(Flags.Mutable) then
-          report.migrationWarning(AmbiguousNamedTupleAssignment(names.head, elemValues.head), tree.srcPos)
         Apply(
           Apply(
             TypeApply(
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index 89ce01231fed..e7bd7d874634 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -3398,6 +3398,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
   /** Translate tuples of all arities */
   def typedTuple(tree: untpd.Tuple, pt: Type)(using Context): Tree =
     val tree1 = desugar.tuple(tree, pt)
+    checkAmbiguousNamedTupleAssignment(tree)
     if tree1 ne tree then typed(tree1, pt)
     else
       val arity = tree.trees.length
@@ -3423,6 +3424,18 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
           val resTpe = TypeOps.nestedPairs(elemTpes)
           app1.cast(resTpe)
 
+ /** Checks if `tree` is a named tuple with one element that could be
+  *  interpreted as an assignment, such as `(x = 1)`. If so, issues a warning.
+  */
+  def checkAmbiguousNamedTupleAssignment(tree: untpd.Tuple)(using Context): Unit =
+    tree.trees match
+      case List(NamedArg(name, value)) =>
+        val typedName = typedIdent(untpd.Ident(name), WildcardType)
+        val sym = typedName.symbol
+        if sym.exists && (sym.is(Flags.Mutable) || sym.setter.exists) then
+          report.migrationWarning(AmbiguousNamedTupleAssignment(name, value), tree.srcPos)
+      case _ => ()
+
   /** Retrieve symbol attached to given tree */
   protected def retrieveSym(tree: untpd.Tree)(using Context): Symbol = tree.removeAttachment(SymOfTree) match {
     case Some(sym) =>
diff --git a/tests/pos/21681d.scala b/tests/pos/21681d.scala
new file mode 100644
index 000000000000..97a01dec74aa
--- /dev/null
+++ b/tests/pos/21681d.scala
@@ -0,0 +1,16 @@
+def test1() =
+  class Person:
+    def age: Int = ???
+    def age_=(x: Int): Unit = ???
+
+  val person = Person()
+  
+  (person.age = 29) // no warn (interpreted as `person.age_=(29)`)
+
+def test2() =
+  class Person:
+    var age: Int = 28
+
+  val person = Person()
+  
+  (person.age = 29) // no warn (interpreted as `person.age_=(29)`)
diff --git a/tests/warn/21681b.check b/tests/warn/21681b.check
new file mode 100644
index 000000000000..32760e00ebb6
--- /dev/null
+++ b/tests/warn/21681b.check
@@ -0,0 +1,7 @@
+-- [E203] Syntax Migration Warning: tests/warn/21681b.scala:3:2 --------------------------------------------------------
+3 |  (age = 29) // warn
+  |  ^^^^^^^^^^
+  |  Ambiguous syntax: this is interpreted as a named tuple with one element,
+  |  not as an assignment.
+  |
+  |  To assign a value, use curly braces: `{age = 29}`.
diff --git a/tests/warn/21681b.scala b/tests/warn/21681b.scala
new file mode 100644
index 000000000000..710d69b0dd23
--- /dev/null
+++ b/tests/warn/21681b.scala
@@ -0,0 +1,3 @@
+object Test:
+  var age: Int = 28
+  (age = 29) // warn

From d1e68f19c99d4171f0c4a6f17cef0ceb72a20bd8 Mon Sep 17 00:00:00 2001
From: Matt Bovel <matthieu@bovel.net>
Date: Tue, 22 Oct 2024 14:09:45 +0200
Subject: [PATCH 35/39] Try to type as an `Assign`

---
 compiler/src/dotty/tools/dotc/typer/Typer.scala | 8 +++++---
 tests/warn/21681c.check                         | 7 +++++++
 tests/warn/21681c.scala                         | 5 +++++
 3 files changed, 17 insertions(+), 3 deletions(-)
 create mode 100644 tests/warn/21681c.check
 create mode 100644 tests/warn/21681c.scala

diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index e7bd7d874634..23855455e67b 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -3430,9 +3430,11 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
   def checkAmbiguousNamedTupleAssignment(tree: untpd.Tuple)(using Context): Unit =
     tree.trees match
       case List(NamedArg(name, value)) =>
-        val typedName = typedIdent(untpd.Ident(name), WildcardType)
-        val sym = typedName.symbol
-        if sym.exists && (sym.is(Flags.Mutable) || sym.setter.exists) then
+        val tmpCtx = ctx.fresh.setNewTyperState()
+        typedAssign(untpd.Assign(untpd.Ident(name), value), WildcardType)(using tmpCtx)
+        if !tmpCtx.reporter.hasErrors then
+          // If there are no errors typing the above, then the named tuple is
+          // ambiguous and we issue a warning.
           report.migrationWarning(AmbiguousNamedTupleAssignment(name, value), tree.srcPos)
       case _ => ()
 
diff --git a/tests/warn/21681c.check b/tests/warn/21681c.check
new file mode 100644
index 000000000000..11c427f87cfe
--- /dev/null
+++ b/tests/warn/21681c.check
@@ -0,0 +1,7 @@
+-- [E203] Syntax Migration Warning: tests/warn/21681c.scala:5:2 --------------------------------------------------------
+5 |  (age = 29) // warn
+  |  ^^^^^^^^^^
+  |  Ambiguous syntax: this is interpreted as a named tuple with one element,
+  |  not as an assignment.
+  |
+  |  To assign a value, use curly braces: `{age = 29}`.
diff --git a/tests/warn/21681c.scala b/tests/warn/21681c.scala
new file mode 100644
index 000000000000..5e2eae11708c
--- /dev/null
+++ b/tests/warn/21681c.scala
@@ -0,0 +1,5 @@
+object Test:
+  def age: Int = ???
+  def age_=(x: Int): Unit = ()
+  age = 29
+  (age = 29) // warn

From ecc332fe6feccb893226c5705038772fb36b9f9b Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Tue, 22 Oct 2024 18:56:56 +0200
Subject: [PATCH 36/39] Scala 2 forwardport: `-Yprofile-trace` (#19897)

* Scala 2 tracing profiler backport from
https://github.com/scala/scala/pull/7364 extended with more Scala 3
idiomatic syntax based on inlined methods
* Fixes the `context.profiler` which could have been `null`, now it's
initially a NoOp Profiler
* Check dependencies of `-Yprofile-enabled` dependent tasks, now we get
an error if `-Yprofile-trace` is set without `-Yprofile-enabled`
---
 compiler/src/dotty/tools/dotc/Compiler.scala  |   5 +-
 compiler/src/dotty/tools/dotc/Run.scala       |   7 +-
 .../tools/dotc/config/ScalaSettings.scala     |  10 +-
 .../dotty/tools/dotc/config/Settings.scala    |  15 +-
 .../src/dotty/tools/dotc/core/Contexts.scala  |   1 +
 .../src/dotty/tools/dotc/core/Phases.scala    |   2 +-
 .../dotty/tools/dotc/core/SymbolLoaders.scala |  12 +-
 .../tools/dotc/profile/ChromeTrace.scala      | 190 +++++++++++++
 .../dotty/tools/dotc/profile/FileUtils.scala  | 204 ++++++++++++++
 .../dotty/tools/dotc/profile/Profiler.scala   | 256 ++++++++++++++----
 .../dotc/profile/ThreadPoolFactory.scala      |   4 +-
 .../dotty/tools/dotc/transform/Splicer.scala  |   5 +-
 .../dotty/tools/dotc/typer/Implicits.scala    |   2 +-
 .../src/dotty/tools/dotc/typer/Typer.scala    |   8 +-
 .../dotty/tools/dotc/typer/TyperPhase.scala   |   2 +-
 .../tools/dotc/profile/ChromeTraceTest.scala  |  93 +++++++
 .../tools/dotc/profile/FileUtilsTest.scala    |  91 +++++++
 .../pc/completions/CompletionProvider.scala   |   6 +-
 18 files changed, 835 insertions(+), 78 deletions(-)
 create mode 100644 compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala
 create mode 100644 compiler/src/dotty/tools/dotc/profile/FileUtils.scala
 create mode 100644 compiler/test/dotty/tools/dotc/profile/ChromeTraceTest.scala
 create mode 100644 compiler/test/dotty/tools/dotc/profile/FileUtilsTest.scala

diff --git a/compiler/src/dotty/tools/dotc/Compiler.scala b/compiler/src/dotty/tools/dotc/Compiler.scala
index f9503e4f8554..d8ba1ab5dc2e 100644
--- a/compiler/src/dotty/tools/dotc/Compiler.scala
+++ b/compiler/src/dotty/tools/dotc/Compiler.scala
@@ -152,7 +152,10 @@ class Compiler {
     List(new GenBCode) ::             // Generate JVM bytecode
     Nil
 
-  var runId: Int = 1
+  // TODO: Initially 0, so that the first nextRunId call would return InitialRunId == 1
+  // Changing the initial runId from 1 to 0 makes the scala2-library-bootstrap fail to compile,
+  // when the underlying issue is fixed, please update dotc.profiler.RealProfiler.chromeTrace logic
+  private var runId: Int = 1
   def nextRunId: Int = {
     runId += 1; runId
   }
diff --git a/compiler/src/dotty/tools/dotc/Run.scala b/compiler/src/dotty/tools/dotc/Run.scala
index 11a0430480d9..50fd668c7696 100644
--- a/compiler/src/dotty/tools/dotc/Run.scala
+++ b/compiler/src/dotty/tools/dotc/Run.scala
@@ -339,10 +339,9 @@ class Run(comp: Compiler, ictx: Context) extends ImplicitRunInfo with Constraint
         if phaseWillRun then
           Stats.trackTime(s"phase time ms/$phase") {
             val start = System.currentTimeMillis
-            val profileBefore = profiler.beforePhase(phase)
-            try units = phase.runOn(units)
-            catch case _: InterruptedException => cancelInterrupted()
-            profiler.afterPhase(phase, profileBefore)
+            profiler.onPhase(phase):
+              try units = phase.runOn(units)
+              catch case _: InterruptedException => cancelInterrupted()
             if (ctx.settings.Xprint.value.containsPhase(phase))
               for (unit <- units)
                 def printCtx(unit: CompilationUnit) = phase.printingContext(
diff --git a/compiler/src/dotty/tools/dotc/config/ScalaSettings.scala b/compiler/src/dotty/tools/dotc/config/ScalaSettings.scala
index 72a051ea8154..6ef33d24f8be 100644
--- a/compiler/src/dotty/tools/dotc/config/ScalaSettings.scala
+++ b/compiler/src/dotty/tools/dotc/config/ScalaSettings.scala
@@ -441,12 +441,10 @@ private sealed trait YSettings:
   val YlegacyLazyVals: Setting[Boolean] = BooleanSetting(ForkSetting, "Ylegacy-lazy-vals", "Use legacy (pre 3.3.0) implementation of lazy vals.")
   val YcompileScala2Library: Setting[Boolean] = BooleanSetting(ForkSetting, "Ycompile-scala2-library", "Used when compiling the Scala 2 standard library.")
   val YprofileEnabled: Setting[Boolean] = BooleanSetting(ForkSetting, "Yprofile-enabled", "Enable profiling.")
-  val YprofileDestination: Setting[String] = StringSetting(ForkSetting, "Yprofile-destination", "file", "Where to send profiling output - specify a file, default is to the console.", "")
-      //.withPostSetHook( _ => YprofileEnabled.value = true )
-  val YprofileExternalTool: Setting[List[String]] = PhasesSetting(ForkSetting, "Yprofile-external-tool", "Enable profiling for a phase using an external tool hook. Generally only useful for a single phase.", "typer")
-      //.withPostSetHook( _ => YprofileEnabled.value = true )
-  val YprofileRunGcBetweenPhases: Setting[List[String]] = PhasesSetting(ForkSetting, "Yprofile-run-gc", "Run a GC between phases - this allows heap size to be accurate at the expense of more time. Specify a list of phases, or *", "_")
-      //.withPostSetHook( _ => YprofileEnabled.value = true )
+  val YprofileDestination: Setting[String] = StringSetting(ForkSetting, "Yprofile-destination", "file", "Where to send profiling output - specify a file, default is to the console.", "", depends = List(YprofileEnabled -> true))
+  val YprofileExternalTool: Setting[List[String]] = PhasesSetting(ForkSetting, "Yprofile-external-tool", "Enable profiling for a phase using an external tool hook. Generally only useful for a single phase.", "typer", depends = List(YprofileEnabled -> true))
+  val YprofileRunGcBetweenPhases: Setting[List[String]] = PhasesSetting(ForkSetting, "Yprofile-run-gc", "Run a GC between phases - this allows heap size to be accurate at the expense of more time. Specify a list of phases, or *", "_", depends = List(YprofileEnabled -> true))
+  val YprofileTrace: Setting[String]  = StringSetting(ForkSetting, "Yprofile-trace", "file", s"Capture trace of compilation in JSON Chrome Trace format to the specified file. This option requires ${YprofileEnabled.name}. The output file can be visualized using https://ui.perfetto.dev/.", "", depends = List(YprofileEnabled -> true))
 
   val YbestEffort: Setting[Boolean] = BooleanSetting(ForkSetting, "Ybest-effort", "Enable best-effort compilation attempting to produce betasty to the META-INF/best-effort directory, regardless of errors, as part of the pickler phase.")
   val YwithBestEffortTasty: Setting[Boolean] = BooleanSetting(ForkSetting, "Ywith-best-effort-tasty", "Allow to compile using best-effort tasty files. If such file is used, the compiler will stop after the pickler phase.")
diff --git a/compiler/src/dotty/tools/dotc/config/Settings.scala b/compiler/src/dotty/tools/dotc/config/Settings.scala
index a5fc6a64aa45..f85f2cc57de4 100644
--- a/compiler/src/dotty/tools/dotc/config/Settings.scala
+++ b/compiler/src/dotty/tools/dotc/config/Settings.scala
@@ -73,6 +73,11 @@ object Settings:
   def validateSettingString(name: String): Unit =
     assert(settingCharacters.matches(name), s"Setting string $name contains invalid characters")
 
+  /** List of setting-value pairs that are required for another setting to be valid.
+    * For example, `s = Setting(..., depends = List(YprofileEnabled -> true))`
+    * means that `s` requires `YprofileEnabled` to be set to `true`.
+    */
+  type SettingDependencies = List[(Setting[?], Any)]
 
   case class Setting[T: ClassTag] private[Settings] (
     category: SettingCategory,
@@ -83,7 +88,7 @@ object Settings:
     choices: Option[Seq[?]] = None,
     prefix: Option[String] = None,
     aliases: List[String] = Nil,
-    depends: List[(Setting[?], Any)] = Nil,
+    depends: SettingDependencies = Nil,
     ignoreInvalidArgs: Boolean = false,
     preferPrevious: Boolean = false,
     propertyClass: Option[Class[?]] = None,
@@ -385,8 +390,8 @@ object Settings:
     def BooleanSetting(category: SettingCategory, name: String, descr: String, initialValue: Boolean = false, aliases: List[String] = Nil, preferPrevious: Boolean = false, deprecation: Option[Deprecation] = None, ignoreInvalidArgs: Boolean = false): Setting[Boolean] =
       publish(Setting(category, prependName(name), descr, initialValue, aliases = aliases, preferPrevious = preferPrevious, deprecation = deprecation, ignoreInvalidArgs = ignoreInvalidArgs))
 
-    def StringSetting(category: SettingCategory, name: String, helpArg: String, descr: String, default: String, aliases: List[String] = Nil, deprecation: Option[Deprecation] = None): Setting[String] =
-      publish(Setting(category, prependName(name), descr, default, helpArg, aliases = aliases, deprecation = deprecation))
+    def StringSetting(category: SettingCategory, name: String, helpArg: String, descr: String, default: String, aliases: List[String] = Nil, deprecation: Option[Deprecation] = None, depends: SettingDependencies = Nil): Setting[String] =
+      publish(Setting(category, prependName(name), descr, default, helpArg, aliases = aliases, deprecation = deprecation, depends = depends))
 
     def ChoiceSetting(category: SettingCategory, name: String, helpArg: String, descr: String, choices: List[String], default: String, aliases: List[String] = Nil, legacyArgs: Boolean = false, deprecation: Option[Deprecation] = None): Setting[String] =
       publish(Setting(category, prependName(name), descr, default, helpArg, Some(choices), aliases = aliases, legacyArgs = legacyArgs, deprecation = deprecation))
@@ -412,8 +417,8 @@ object Settings:
     def PathSetting(category: SettingCategory, name: String, descr: String, default: String, aliases: List[String] = Nil, deprecation: Option[Deprecation] = None): Setting[String] =
       publish(Setting(category, prependName(name), descr, default, aliases = aliases, deprecation = deprecation))
 
-    def PhasesSetting(category: SettingCategory, name: String, descr: String, default: String = "", aliases: List[String] = Nil, deprecation: Option[Deprecation] = None): Setting[List[String]] =
-      publish(Setting(category, prependName(name), descr, if (default.isEmpty) Nil else List(default), aliases = aliases, deprecation = deprecation))
+    def PhasesSetting(category: SettingCategory, name: String, descr: String, default: String = "", aliases: List[String] = Nil, deprecation: Option[Deprecation] = None, depends: SettingDependencies = Nil): Setting[List[String]] =
+      publish(Setting(category, prependName(name), descr, if (default.isEmpty) Nil else List(default), aliases = aliases, deprecation = deprecation, depends = depends))
 
     def PrefixSetting(category: SettingCategory, name0: String, descr: String, deprecation: Option[Deprecation] = None): Setting[List[String]] =
       val name = prependName(name0)
diff --git a/compiler/src/dotty/tools/dotc/core/Contexts.scala b/compiler/src/dotty/tools/dotc/core/Contexts.scala
index 388720e7f3f4..d69c7408d0b1 100644
--- a/compiler/src/dotty/tools/dotc/core/Contexts.scala
+++ b/compiler/src/dotty/tools/dotc/core/Contexts.scala
@@ -769,6 +769,7 @@ object Contexts {
           .updated(settingsStateLoc, settingsGroup.defaultState)
           .updated(notNullInfosLoc, Nil)
           .updated(compilationUnitLoc, NoCompilationUnit)
+          .updated(profilerLoc, Profiler.NoOp)
       c._searchHistory = new SearchRoot
       c._gadtState = GadtState(GadtConstraint.empty)
       c
diff --git a/compiler/src/dotty/tools/dotc/core/Phases.scala b/compiler/src/dotty/tools/dotc/core/Phases.scala
index 85df3f9f2c18..015cf6fc0f2c 100644
--- a/compiler/src/dotty/tools/dotc/core/Phases.scala
+++ b/compiler/src/dotty/tools/dotc/core/Phases.scala
@@ -370,7 +370,7 @@ object Phases {
       // Test that we are in a state where we need to check if the phase should be skipped for a java file,
       // this prevents checking the expensive `unit.typedAsJava` unnecessarily.
       val doCheckJava = skipIfJava && !isAfterLastJavaPhase
-      for unit <- units do
+      for unit <- units do ctx.profiler.onUnit(this, unit):
         given unitCtx: Context = runCtx.fresh.setPhase(this.start).setCompilationUnit(unit).withRootImports
         if ctx.run.enterUnit(unit) then
           try
diff --git a/compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala b/compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala
index 51e6a5e6138a..5690720a1b3f 100644
--- a/compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala
+++ b/compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala
@@ -8,7 +8,7 @@ import java.nio.channels.ClosedByInterruptException
 import scala.util.control.NonFatal
 
 import dotty.tools.dotc.classpath.FileUtils.{hasTastyExtension, hasBetastyExtension}
-import dotty.tools.io.{ ClassPath, ClassRepresentation, AbstractFile }
+import dotty.tools.io.{ ClassPath, ClassRepresentation, AbstractFile, NoAbstractFile }
 import dotty.tools.backend.jvm.DottyBackendInterface.symExtensions
 
 import Contexts.*, Symbols.*, Flags.*, SymDenotations.*, Types.*, Scopes.*, Names.*
@@ -333,7 +333,15 @@ abstract class SymbolLoader extends LazyType { self =>
     def description(using Context): String = s"proxy to ${self.description}"
   }
 
-  override def complete(root: SymDenotation)(using Context): Unit = {
+  private inline def profileCompletion[T](root: SymDenotation)(inline body: T)(using Context): T = {
+    val sym = root.symbol
+    def associatedFile = root.symbol.associatedFile match
+      case file: AbstractFile => file
+      case _ => NoAbstractFile
+    ctx.profiler.onCompletion(sym, associatedFile)(body)
+  }
+
+  override def complete(root: SymDenotation)(using Context): Unit = profileCompletion(root) {
     def signalError(ex: Exception): Unit = {
       if (ctx.debug) ex.printStackTrace()
       val msg = ex.getMessage()
diff --git a/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala b/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala
new file mode 100644
index 000000000000..c33039f46398
--- /dev/null
+++ b/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala
@@ -0,0 +1,190 @@
+// Scala 2 compiler backport of https://github.com/scala/scala/pull/7364
+/*
+ * 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.dotc.profile
+
+import scala.language.unsafeNulls
+
+import java.io.Closeable
+import java.lang.management.ManagementFactory
+import java.nio.file.{Files, Path}
+import java.util
+import java.util.concurrent.TimeUnit
+
+import scala.collection.mutable
+
+object ChromeTrace {
+  private object EventType {
+    final val Start = "B"
+    final val Instant = "I"
+    final val End = "E"
+    final val Complete = "X"
+
+    final val Counter = "C"
+
+    final val AsyncStart = "b"
+    final val AsyncInstant = "n"
+    final val AsyncEnd = "e"
+  }
+}
+
+/** Allows writing a subset of captrue traces based on https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/preview#
+  * Can be visualized using https://ui.perfetto.dev/, Chrome's about://tracing (outdated) or the tooling in https://www.google.com.au/search?q=catapult+tracing&oq=catapult+tracing+&aqs=chrome..69i57.3974j0j4&sourceid=chrome&ie=UTF-8 */
+final class ChromeTrace(f: Path) extends Closeable {
+  import ChromeTrace.EventType
+  private val traceWriter = FileUtils.newAsyncBufferedWriter(f)
+  private val context = mutable.Stack[JsonContext](TopContext)
+  private val tidCache = new ThreadLocal[String]() {
+    override def initialValue(): String = "%05d".format(Thread.currentThread().getId())
+  }
+  objStart()
+  fld("traceEvents")
+  context.push(ValueContext)
+  arrStart()
+  traceWriter.newLine()
+
+  private val pid = ManagementFactory.getRuntimeMXBean().getName().replaceAll("@.*", "")
+
+  override def close(): Unit = {
+    arrEnd()
+    objEnd()
+    context.pop()
+    tidCache.remove()
+    traceWriter.close()
+  }
+
+  def traceDurationEvent(name: String, startNanos: Long, durationNanos: Long, tid: String = this.tid(), pidSuffix: String = ""): Unit = {
+    val durationMicros = nanosToMicros(durationNanos)
+    val startMicros = nanosToMicros(startNanos)
+    objStart()
+    str("cat", "scalac")
+    str("name", name)
+    str("ph", EventType.Complete)
+    str("tid", tid)
+    writePid(pidSuffix)
+    lng("ts", startMicros)
+    lng("dur", durationMicros)
+    objEnd()
+    traceWriter.newLine()
+  }
+
+  private def writePid(pidSuffix: String) = {
+    if (pidSuffix == "")
+      str("pid", pid)
+    else
+      str2("pid", pid, "-", pidSuffix)
+  }
+
+  def traceCounterEvent(name: String, counterName: String, count: Long, processWide: Boolean): Unit = {
+    objStart()
+    str("cat", "scalac")
+    str("name", name)
+    str("ph", EventType.Counter)
+    str("tid", tid())
+    writePid(pidSuffix = if (processWide) "" else tid())
+    lng("ts", microTime())
+    fld("args")
+    objStart()
+    lng(counterName, count)
+    objEnd()
+    objEnd()
+    traceWriter.newLine()
+  }
+
+  def traceDurationEventStart(cat: String, name: String, colour: String = "", pidSuffix: String = tid()): Unit = traceDurationEventStartEnd(EventType.Start, cat, name, colour, pidSuffix)
+  def traceDurationEventEnd(cat: String, name: String, colour: String = "", pidSuffix: String = tid()): Unit = traceDurationEventStartEnd(EventType.End, cat, name, colour, pidSuffix)
+
+  private def traceDurationEventStartEnd(eventType: String, cat: String, name: String, colour: String, pidSuffix: String = ""): Unit = {
+    objStart()
+    str("cat", cat)
+    str("name", name)
+    str("ph", eventType)
+    writePid(pidSuffix)
+    str("tid", tid())
+    lng("ts", microTime())
+    if (colour != "") {
+      str("cname", colour)
+    }
+    objEnd()
+    traceWriter.newLine()
+  }
+
+  private def tid(): String = tidCache.get()
+
+  private def nanosToMicros(t: Long): Long = TimeUnit.NANOSECONDS.toMicros(t)
+
+  private def microTime(): Long = nanosToMicros(System.nanoTime())
+
+  private sealed abstract class JsonContext
+  private case class ArrayContext(var first: Boolean) extends JsonContext
+  private case class ObjectContext(var first: Boolean) extends JsonContext
+  private case object ValueContext extends JsonContext
+  private case object TopContext extends JsonContext
+
+  private def str(name: String, value: String): Unit = {
+    fld(name)
+    traceWriter.write("\"")
+    traceWriter.write(value) // This assumes no escaping is needed
+    traceWriter.write("\"")
+  }
+  private def str2(name: String, value: String, valueContinued1: String, valueContinued2: String): Unit = {
+    fld(name)
+    traceWriter.write("\"")
+    traceWriter.write(value) // This assumes no escaping is needed
+    traceWriter.write(valueContinued1) // This assumes no escaping is needed
+    traceWriter.write(valueContinued2) // This assumes no escaping is needed
+    traceWriter.write("\"")
+  }
+  private def lng(name: String, value: Long): Unit = {
+    fld(name)
+    traceWriter.write(String.valueOf(value))
+    traceWriter.write("")
+  }
+  private def objStart(): Unit = {
+    context.top match {
+      case ac @ ArrayContext(first) =>
+        if (first) ac.first = false
+        else traceWriter.write(",")
+      case _ =>
+    }
+    context.push(ObjectContext(true))
+    traceWriter.write("{")
+  }
+  private def objEnd(): Unit = {
+    traceWriter.write("}")
+    context.pop()
+  }
+  private def arrStart(): Unit = {
+    traceWriter.write("[")
+    context.push(ArrayContext(true))
+  }
+  private def arrEnd(): Unit = {
+    traceWriter.write("]")
+    context.pop()
+  }
+
+  private def fld(name: String) = {
+    val topContext = context.top
+    topContext match {
+      case oc @ ObjectContext(first) =>
+        if (first) oc.first = false
+        else traceWriter.write(",")
+      case context =>
+        throw new IllegalStateException("Wrong context: " + context)
+    }
+    traceWriter.write("\"")
+    traceWriter.write(name)
+    traceWriter.write("\"")
+    traceWriter.write(":")
+  }
+}
\ No newline at end of file
diff --git a/compiler/src/dotty/tools/dotc/profile/FileUtils.scala b/compiler/src/dotty/tools/dotc/profile/FileUtils.scala
new file mode 100644
index 000000000000..4aec428c05bf
--- /dev/null
+++ b/compiler/src/dotty/tools/dotc/profile/FileUtils.scala
@@ -0,0 +1,204 @@
+// Scala 2 compiler backport of https://github.com/scala/scala/pull/7364
+
+/*
+* 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.dotc.profile
+
+import scala.language.unsafeNulls
+
+import java.io.{BufferedWriter, IOException, OutputStreamWriter, Writer}
+import java.nio.CharBuffer
+import java.nio.charset.{Charset, CharsetEncoder, StandardCharsets}
+import java.nio.file.{Files, OpenOption, Path}
+import java.util.concurrent.LinkedBlockingQueue
+import java.util.concurrent.atomic.AtomicBoolean
+
+
+import scala.concurrent.duration.Duration
+import scala.concurrent.{Await, Promise}
+import scala.util.{Failure, Success}
+import scala.annotation.internal.sharable
+
+object FileUtils {
+  def newAsyncBufferedWriter(path: Path, charset: Charset = StandardCharsets.UTF_8.nn, options: Array[OpenOption] = NO_OPTIONS, threadsafe: Boolean = false): LineWriter = {
+    val encoder: CharsetEncoder = charset.newEncoder
+    val writer = new OutputStreamWriter(Files.newOutputStream(path, options: _*), encoder)
+    newAsyncBufferedWriter(new BufferedWriter(writer), threadsafe)
+  }
+  def newAsyncBufferedWriter(underlying: Writer, threadsafe: Boolean): LineWriter = {
+    val async = new AsyncBufferedWriter(underlying)
+    if (threadsafe) new ThreadsafeWriter(async) else async
+  }
+  private val NO_OPTIONS = new Array[OpenOption](0)
+
+  sealed abstract class LineWriter extends Writer {
+    def newLine(): Unit
+  }
+  private class ThreadsafeWriter(val underlying: AsyncBufferedWriter) extends LineWriter {
+    lock = underlying
+    override def write(c: Int): Unit =
+      lock.synchronized (underlying.write(c))
+
+    override def write(cbuf: Array[Char]): Unit =
+      lock.synchronized (underlying.write(cbuf))
+
+    override def write(cbuf: Array[Char], off: Int, len: Int): Unit =
+      lock.synchronized (underlying.write(cbuf, off, len))
+
+    override def write(str: String): Unit =
+      lock.synchronized (underlying.write(str))
+
+    override def write(str: String, off: Int, len: Int): Unit =
+      lock.synchronized (underlying.write(str, off, len))
+
+    override def flush(): Unit =
+      lock.synchronized (underlying.flush())
+
+    override def close(): Unit =
+      lock.synchronized (underlying.close())
+
+    override def newLine(): Unit =
+      lock.synchronized (underlying.newLine())
+
+  }
+
+  private object AsyncBufferedWriter {
+    @sharable private val Close = CharBuffer.allocate(0)
+    @sharable private val Flush = CharBuffer.allocate(0)
+  }
+  private class AsyncBufferedWriter(val underlying: Writer, bufferSize : Int = 4096) extends LineWriter {
+    private var current: CharBuffer = allocate
+    override def write(c: Int): Unit = super.write(c)
+    private def flushAsync(): Unit = {
+      background.ensureProcessed(current)
+      current = allocate
+    }
+//    allocate or reuse a CharArray which is guaranteed to have a backing array
+    private def allocate: CharBuffer = {
+      val reused = background.reuseBuffer
+      if (reused eq null)      CharBuffer.allocate(bufferSize)
+      else {
+        //we don't care about race conditions
+        background.reuseBuffer = null
+        reused.clear()
+        reused
+      }
+    }
+
+    override def write(cbuf: Array[Char], initialOffset: Int, initialLength: Int): Unit = {
+      var offset = initialOffset
+      var length = initialLength
+      while (length > 0) {
+        val capacity = current.remaining()
+        if (length <= capacity) {
+          current.put(cbuf, offset, length)
+          length = 0
+        } else {
+          current.put(cbuf, offset, capacity)
+          flushAsync()
+          length -= capacity
+          offset += capacity
+        }
+      }
+    }
+
+    override def write(s: String,  initialOffset: Int, initialLength: Int): Unit = {
+      var offset = initialOffset
+      var length = initialLength
+      while (length > 0) {
+        val capacity = current.remaining()
+        if (length <= capacity) {
+          current.put(s, offset, offset + length)
+          length = 0
+        } else {
+          current.put(s, offset, offset + capacity)
+          flushAsync()
+          length -= capacity
+          offset += capacity
+        }
+      }
+    }
+
+    def newLine(): Unit = write(scala.util.Properties.lineSeparator)
+
+    /** slightly breaks the flush contract in that the flush is not complete when the method returns */
+    override def flush(): Unit = {
+      flushAsync()
+    }
+
+    override def close(): Unit = {
+      background.ensureProcessed(current)
+      background.ensureProcessed(AsyncBufferedWriter.Close)
+      current = null
+      Await.result(background.asyncStatus.future, Duration.Inf)
+      underlying.close()
+    }
+    private object background extends Runnable{
+
+      import scala.concurrent.ExecutionContext.Implicits.global
+
+      private val pending = new LinkedBlockingQueue[CharBuffer]
+      //a failure detected will case an Failure, Success indicates a close
+      val asyncStatus = Promise[Unit]()
+      private val scheduled = new AtomicBoolean
+      @volatile var reuseBuffer: CharBuffer = _
+
+      def ensureProcessed(buffer: CharBuffer): Unit = {
+        if (asyncStatus.isCompleted) {
+          asyncStatus.future.value.get match {
+            case Success(()) => throw new IllegalStateException("closed")
+            case Failure(t) => throw new IOException("async failure", t)
+          }
+        }
+
+        //order is essential - add to the queue before the CAS
+        pending.add(buffer)
+        if (scheduled.compareAndSet(false, true)) {
+          global.execute(background)
+        }
+      }
+
+      def run(): Unit = {
+        try {
+          while (!pending.isEmpty) {
+            val next = pending.poll()
+            if (next eq AsyncBufferedWriter.Flush) {
+              underlying.flush()
+            } else if (next eq AsyncBufferedWriter.Close) {
+              underlying.flush()
+              underlying.close()
+              asyncStatus.trySuccess(())
+            } else {
+              val array = next.array()
+              next.flip()
+              underlying.write(array, next.arrayOffset() + next.position(), next.limit())
+              reuseBuffer = next
+            }
+          }
+        } catch {
+          case t: Throwable =>
+            asyncStatus.tryFailure(t)
+            throw t
+        }
+        finally scheduled.set(false)
+
+        //we are not scheduled any more
+        //as a last check ensure that we didnt race with an addition to the queue
+        //order is essential - queue is checked before CAS
+        if ((!pending.isEmpty) && scheduled.compareAndSet(false, true)) {
+          global.execute(background)
+        }
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/compiler/src/dotty/tools/dotc/profile/Profiler.scala b/compiler/src/dotty/tools/dotc/profile/Profiler.scala
index a13c9d41b529..69a806215ddd 100644
--- a/compiler/src/dotty/tools/dotc/profile/Profiler.scala
+++ b/compiler/src/dotty/tools/dotc/profile/Profiler.scala
@@ -4,6 +4,7 @@ import scala.annotation.*
 import scala.language.unsafeNulls
 
 import java.io.{FileWriter, PrintWriter}
+import java.nio.file.Paths
 import java.lang.management.{ManagementFactory, GarbageCollectorMXBean, RuntimeMXBean, MemoryMXBean, ClassLoadingMXBean, CompilationMXBean}
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.atomic.AtomicInteger
@@ -12,8 +13,15 @@ import javax.management.{Notification, NotificationEmitter, NotificationListener
 
 import dotty.tools.dotc.core.Phases.Phase
 import dotty.tools.dotc.core.Contexts.*
+import dotty.tools.dotc.CompilationUnit
+import dotty.tools.dotc.core.Types.Type
+import dotty.tools.dotc.core.Symbols.{Symbol, NoSymbol}
+import dotty.tools.dotc.core.Flags
+import dotty.tools.backend.jvm.DottyBackendInterface.symExtensions
 import dotty.tools.io.AbstractFile
 import annotation.internal.sharable
+import dotty.tools.dotc.core.Periods.InitialRunId
+import scala.collection.mutable.UnrolledBuffer
 
 object Profiler {
   def apply()(using Context): Profiler =
@@ -25,14 +33,19 @@ object Profiler {
       new RealProfiler(reporter)
     }
 
-  private[profile] val emptySnap: ProfileSnap = ProfileSnap(0, "", 0, 0, 0, 0, 0, 0)
+  final def NoOp: Profiler = NoOpProfiler
+
+  private[profile] val emptySnap: ProfileSnap = ProfileSnap(0, "", 0, 0, 0, 0, 0, 0, 0, 0)
 }
 
-case class GcEventData(pool:String, reportTimeNs: Long, gcStartMillis:Long, gcEndMillis:Long, name:String, action:String, cause:String, threads:Long)
+case class GcEventData(pool:String, reportTimeNs: Long, gcStartMillis:Long, gcEndMillis:Long, durationMillis: Long, name:String, action:String, cause:String, threads:Long){
+  val endNanos = System.nanoTime()
+}
 
 case class ProfileSnap(threadId: Long, threadName: String, snapTimeNanos : Long,
                        idleTimeNanos:Long, cpuTimeNanos: Long, userTimeNanos: Long,
-                       allocatedBytes:Long, heapBytes:Long) {
+                       allocatedBytes:Long, heapBytes:Long,
+                       totalClassesLoaded: Long, totalJITCompilationTime: Long) {
   def updateHeap(heapBytes:Long): ProfileSnap =
     copy(heapBytes = heapBytes)
 }
@@ -66,22 +79,63 @@ case class ProfileRange(start: ProfileSnap, end:ProfileSnap, phase:Phase, purpos
   def retainedHeapMB: Double = toMegaBytes(end.heapBytes - start.heapBytes)
 }
 
+private opaque type TracedEventId <: String = String
+private object TracedEventId:
+  def apply(stringValue: String): TracedEventId = stringValue
+  final val Empty: TracedEventId = ""
+
 sealed trait Profiler {
 
   def finished(): Unit
 
-  def beforePhase(phase: Phase): ProfileSnap
-
-  def afterPhase(phase: Phase, profileBefore: ProfileSnap): Unit
+  inline def onPhase[T](phase: Phase)(inline body: T): T =
+    val (event, snapshot) = beforePhase(phase)
+    try body
+    finally afterPhase(event, phase, snapshot)
+  protected final val EmptyPhaseEvent = (TracedEventId.Empty, Profiler.emptySnap)
+  protected def beforePhase(phase: Phase): (TracedEventId, ProfileSnap) = EmptyPhaseEvent
+  protected def afterPhase(event: TracedEventId, phase: Phase, profileBefore: ProfileSnap): Unit = ()
+
+  inline def onUnit[T](phase: Phase, unit: CompilationUnit)(inline body: T): T =
+    val event = beforeUnit(phase, unit)
+    try body
+    finally afterUnit(event)
+  protected def beforeUnit(phase: Phase, unit: CompilationUnit): TracedEventId = TracedEventId.Empty
+  protected def afterUnit(event: TracedEventId): Unit = ()
+
+  inline def onTypedDef[T](sym: Symbol)(inline body: T): T =
+    val event = beforeTypedDef(sym)
+    try body
+    finally afterTypedDef(event)
+   protected def beforeTypedDef(sym: Symbol): TracedEventId = TracedEventId.Empty
+   protected def afterTypedDef(token: TracedEventId): Unit = ()
+
+  inline def onImplicitSearch[T](pt: Type)(inline body: T): T =
+    val event = beforeImplicitSearch(pt)
+    try body
+    finally afterImplicitSearch(event)
+  protected def beforeImplicitSearch(pt: Type): TracedEventId  = TracedEventId.Empty
+  protected def afterImplicitSearch(event: TracedEventId): Unit = ()
+
+  inline def onMacroSplice[T](macroSym: Symbol)(inline body: T): T =
+    val event = beforeMacroSplice(macroSym)
+    try body
+    finally afterMacroSplice(event)
+  protected def beforeMacroSplice(macroSym: Symbol): TracedEventId = TracedEventId.Empty
+  protected def afterMacroSplice(event: TracedEventId): Unit = ()
+
+  inline def onCompletion[T](root: Symbol, associatedFile: => AbstractFile)(inline body: T): T =
+    val (event, completionName) = beforeCompletion(root, associatedFile)
+    try body
+    finally afterCompletion(event, completionName)
+  protected final val EmptyCompletionEvent = (TracedEventId.Empty, "")
+  protected def beforeCompletion(root: Symbol, associatedFile: => AbstractFile): (TracedEventId, String) = EmptyCompletionEvent
+  protected def afterCompletion(event: TracedEventId, completionName: String): Unit = ()
 }
 private [profile] object NoOpProfiler extends Profiler {
-
-  override def beforePhase(phase: Phase): ProfileSnap = Profiler.emptySnap
-
-  override def afterPhase(phase: Phase, profileBefore: ProfileSnap): Unit = ()
-
   override def finished(): Unit = ()
 }
+
 private [profile] object RealProfiler {
   import scala.jdk.CollectionConverters.*
   val runtimeMx: RuntimeMXBean = ManagementFactory.getRuntimeMXBean
@@ -92,17 +146,6 @@ private [profile] object RealProfiler {
   val threadMx: ExtendedThreadMxBean = ExtendedThreadMxBean.proxy
   if (threadMx.isThreadCpuTimeSupported) threadMx.setThreadCpuTimeEnabled(true)
   private val idGen = new AtomicInteger()
-}
-
-private [profile] class RealProfiler(reporter : ProfileReporter)(using Context) extends Profiler with NotificationListener {
-  def completeBackground(threadRange: ProfileRange): Unit =
-    reporter.reportBackground(this, threadRange)
-
-  def outDir: AbstractFile = ctx.settings.outputDir.value
-
-  val id: Int = RealProfiler.idGen.incrementAndGet()
-
-  private val mainThread = Thread.currentThread()
 
   @nowarn("cat=deprecation")
   private[profile] def snapThread(idleTimeNanos: Long): ProfileSnap = {
@@ -117,13 +160,47 @@ private [profile] class RealProfiler(reporter : ProfileReporter)(using Context)
       cpuTimeNanos = threadMx.getCurrentThreadCpuTime,
       userTimeNanos = threadMx.getCurrentThreadUserTime,
       allocatedBytes = threadMx.getThreadAllocatedBytes(Thread.currentThread().getId),
-      heapBytes = readHeapUsage()
+      heapBytes = readHeapUsage(),
+      totalClassesLoaded = classLoaderMx.getTotalLoadedClassCount,
+      totalJITCompilationTime = compileMx.getTotalCompilationTime
     )
   }
   private def readHeapUsage() = RealProfiler.memoryMx.getHeapMemoryUsage.getUsed
+}
+
+private [profile] class RealProfiler(reporter : ProfileReporter)(using Context) extends Profiler with NotificationListener {
+  val id: Int = RealProfiler.idGen.incrementAndGet()
+  private val mainThread = Thread.currentThread()
+  private val gcEvents = UnrolledBuffer[GcEventData]()
+  private var nextAfterUnitSnap: Long = System.nanoTime()
+
+  private final val GcThreadId = "GC"
+
+  enum Category:
+    def name: String = this.toString().toLowerCase()
+    case Run, Phase, File, TypeCheck, Implicit, Macro, Completion
+  private [profile] val chromeTrace =
+    if ctx.settings.YprofileTrace.isDefault
+    then null
+    else
+      val filename = ctx.settings.YprofileTrace.value
+      // Compilation units requiring multi-stage compilation (macros) would create a new profiler instances
+      // We need to store the traces in the seperate file to prevent overriding its content.
+      // Alternatives: sharing ChromeTrace instance between all runs / manual concatation after all runs are done
+      // FIXME: The first assigned runId is equal to 2 instead of 1 (InitialRunId).
+      // Fix me when bug described in Compiler.runId is resolved by removing +/- 1 adjustments
+      val suffix = if ctx.runId > InitialRunId + 1 then s".${ctx.runId - 1}" else ""
+      ChromeTrace(Paths.get(s"$filename$suffix"))
+
+  private val compilerRunEvent: TracedEventId = traceDurationStart(Category.Run, s"scalac-$id")
+
+  def completeBackground(threadRange: ProfileRange): Unit =
+    reporter.reportBackground(this, threadRange)
+
+  def outDir: AbstractFile = ctx.settings.outputDir.value
 
   @nowarn
-  private def doGC: Unit = {
+  private def doGC(): Unit = {
     System.gc()
     System.runFinalization()
   }
@@ -142,6 +219,15 @@ private [profile] class RealProfiler(reporter : ProfileReporter)(using Context)
       case gc =>
     }
     reporter.close(this)
+    if chromeTrace != null then
+      traceDurationEnd(Category.Run, compilerRunEvent)
+      for gcEvent <- gcEvents
+      do {
+        val durationNanos = TimeUnit.MILLISECONDS.toNanos(gcEvent.durationMillis)
+        val startNanos = gcEvent.endNanos - durationNanos
+        chromeTrace.traceDurationEvent(gcEvent.name, startNanos, durationNanos, tid = GcThreadId)
+      }
+      chromeTrace.close()
   }
 
 
@@ -150,10 +236,7 @@ private [profile] class RealProfiler(reporter : ProfileReporter)(using Context)
     import java.lang.{Integer => jInt}
     val reportNs = System.nanoTime()
     val data = notification.getUserData
-    val seq = notification.getSequenceNumber
-    val message = notification.getMessage
     val tpe = notification.getType
-    val time= notification.getTimeStamp
     data match {
       case cd: CompositeData if tpe == "com.sun.management.gc.notification" =>
         val name = cd.get("gcName").toString
@@ -164,49 +247,127 @@ private [profile] class RealProfiler(reporter : ProfileReporter)(using Context)
         val startTime = info.get("startTime").asInstanceOf[jLong].longValue()
         val endTime = info.get("endTime").asInstanceOf[jLong].longValue()
         val threads = info.get("GcThreadCount").asInstanceOf[jInt].longValue()
-        reporter.reportGc(GcEventData("", reportNs, startTime, endTime, name, action, cause, threads))
+        val gcEvent = GcEventData("", reportNs, startTime, endTime, duration, name, action, cause, threads)
+        synchronized { gcEvents += gcEvent }
+        reporter.reportGc(gcEvent)
     }
   }
 
-  override def afterPhase(phase: Phase, snapBefore: ProfileSnap): Unit = {
+  override def afterPhase(event: TracedEventId, phase: Phase, snapBefore: ProfileSnap): Unit = {
     assert(mainThread eq Thread.currentThread())
-    val initialSnap = snapThread(0)
+    val initialSnap = RealProfiler.snapThread(0)
     if (ctx.settings.YprofileExternalTool.value.contains(phase.toString)) {
       println("Profile hook stop")
       ExternalToolHook.after()
     }
     val finalSnap = if (ctx.settings.YprofileRunGcBetweenPhases.value.contains(phase.toString)) {
-      doGC
-      initialSnap.updateHeap(readHeapUsage())
+      doGC()
+      initialSnap.updateHeap(RealProfiler.readHeapUsage())
     }
     else initialSnap
-
+    traceDurationEnd(Category.Phase, event)
+    traceThreadSnapshotCounters()
     reporter.reportForeground(this, ProfileRange(snapBefore, finalSnap, phase, "", 0, Thread.currentThread))
   }
 
-  override def beforePhase(phase: Phase): ProfileSnap = {
+  override def beforePhase(phase: Phase): (TracedEventId, ProfileSnap) = {
     assert(mainThread eq Thread.currentThread())
+    traceThreadSnapshotCounters()
+    val eventId = traceDurationStart(Category.Phase, phase.phaseName)
     if (ctx.settings.YprofileRunGcBetweenPhases.value.contains(phase.toString))
-      doGC
+      doGC()
     if (ctx.settings.YprofileExternalTool.value.contains(phase.toString)) {
       println("Profile hook start")
       ExternalToolHook.before()
     }
-    snapThread(0)
+    (eventId, RealProfiler.snapThread(0))
+  }
+
+  override def beforeUnit(phase: Phase, unit: CompilationUnit): TracedEventId = {
+    assert(mainThread eq Thread.currentThread())
+    if chromeTrace != null then
+      traceThreadSnapshotCounters()
+      traceDurationStart(Category.File, unit.source.name)
+    else TracedEventId.Empty
+  }
+
+  override def afterUnit(event: TracedEventId): Unit = {
+    assert(mainThread eq Thread.currentThread())
+    if chromeTrace != null then
+      traceDurationEnd(Category.File, event)
+      traceThreadSnapshotCounters()
   }
-}
 
+  private def traceThreadSnapshotCounters(initialSnap: => ProfileSnap = RealProfiler.snapThread(0)) =
+    if chromeTrace != null && System.nanoTime() > nextAfterUnitSnap then {
+      val snap = initialSnap
+      chromeTrace.traceCounterEvent("allocBytes", "allocBytes", snap.allocatedBytes, processWide = false)
+      chromeTrace.traceCounterEvent("heapBytes", "heapBytes", snap.heapBytes, processWide = true)
+      chromeTrace.traceCounterEvent("classesLoaded", "classesLoaded", snap.totalClassesLoaded, processWide = true)
+      chromeTrace.traceCounterEvent("jitCompilationTime", "jitCompilationTime", snap.totalJITCompilationTime, processWide = true)
+      chromeTrace.traceCounterEvent("userTime", "userTime", snap.userTimeNanos, processWide = false)
+      chromeTrace.traceCounterEvent("cpuTime", "cpuTime", snap.cpuTimeNanos, processWide = false)
+      chromeTrace.traceCounterEvent("idleTime", "idleTime", snap.idleTimeNanos, processWide = false)
+      nextAfterUnitSnap = System.nanoTime() + 10 * 1000 * 1000
+    }
 
-case class EventType(name: String)
-object EventType {
-  //main thread with other tasks
-  val MAIN: EventType = EventType("main")
-  //other task ( background thread)
-  val BACKGROUND: EventType = EventType("background")
-  //total for compile
-  val GC: EventType = EventType("GC")
+  override def beforeTypedDef(sym: Symbol): TracedEventId = traceDurationStart(Category.TypeCheck, symbolName(sym))
+  override def afterTypedDef(event: TracedEventId): Unit = traceDurationEnd(Category.TypeCheck, event)
+
+  override def beforeImplicitSearch(pt: Type): TracedEventId = traceDurationStart(Category.Implicit, s"?[${symbolName(pt.typeSymbol)}]", colour = "yellow")
+  override def afterImplicitSearch(event: TracedEventId): Unit = traceDurationEnd(Category.Implicit, event, colour = "yellow")
+
+  override def beforeMacroSplice(macroSym: Symbol): TracedEventId = traceDurationStart(Category.Macro, s"«${symbolName(macroSym)}»", colour = "olive")
+  override def afterMacroSplice(event: TracedEventId): Unit = traceDurationEnd(Category.Macro, event, colour = "olive")
+
+  override def beforeCompletion(root: Symbol, associatedFile: => AbstractFile): (TracedEventId, String) =
+    if chromeTrace == null
+    then EmptyCompletionEvent
+    else
+      val completionName = this.completionName(root, associatedFile)
+      val event = TracedEventId(associatedFile.name)
+      chromeTrace.traceDurationEventStart(Category.Completion.name, "↯", colour = "thread_state_sleeping")
+      chromeTrace.traceDurationEventStart(Category.File.name, event)
+      chromeTrace.traceDurationEventStart(Category.Completion.name, completionName)
+      (event, completionName)
+
+  override def afterCompletion(event: TracedEventId, completionName: String): Unit =
+    if chromeTrace != null
+    then
+      chromeTrace.traceDurationEventEnd(Category.Completion.name, completionName)
+      chromeTrace.traceDurationEventEnd(Category.File.name, event)
+      chromeTrace.traceDurationEventEnd(Category.Completion.name, "↯", colour = "thread_state_sleeping")
+
+  private inline def traceDurationStart(category: Category, inline eventName: String, colour: String = ""): TracedEventId =
+    if chromeTrace == null
+    then TracedEventId.Empty
+    else
+      val event = TracedEventId(eventName)
+      chromeTrace.traceDurationEventStart(category.name, event, colour)
+      event
+
+  private inline def traceDurationEnd(category: Category, event: TracedEventId, colour: String = ""): Unit =
+    if chromeTrace != null then
+      chromeTrace.traceDurationEventEnd(category.name, event, colour)
+
+  private def symbolName(sym: Symbol): String = s"${sym.showKind} ${sym.showName}"
+  private def completionName(root: Symbol, associatedFile: AbstractFile): String =
+    def isTopLevel = root.owner != NoSymbol && root.owner.is(Flags.Package)
+    if root.is(Flags.Package) || isTopLevel
+    then root.javaBinaryName
+    else
+      val enclosing = root.enclosingClass
+      s"${enclosing.javaBinaryName}::${root.name}"
 }
 
+enum EventType(name: String):
+  // main thread with other tasks
+  case MAIN extends EventType("main")
+  // other task ( background thread)
+  case BACKGROUND extends EventType("background")
+  // total for compile
+  case GC extends EventType("GC")
+
 sealed trait ProfileReporter {
   def reportBackground(profiler: RealProfiler, threadRange: ProfileRange): Unit
   def reportForeground(profiler: RealProfiler, threadRange: ProfileRange): Unit
@@ -259,9 +420,8 @@ class StreamProfileReporter(out:PrintWriter) extends ProfileReporter {
     out.println(s"${EventType.GC},$start,${data.reportTimeNs},${data.gcStartMillis}, ${data.gcEndMillis},${data.name},${data.action},${data.cause},${data.threads}")
   }
 
-
   override def close(profiler: RealProfiler): Unit = {
-    out.flush
-    out.close
+    out.flush()
+    out.close()
   }
 }
diff --git a/compiler/src/dotty/tools/dotc/profile/ThreadPoolFactory.scala b/compiler/src/dotty/tools/dotc/profile/ThreadPoolFactory.scala
index e3ea69d9be06..1a81153b9b08 100644
--- a/compiler/src/dotty/tools/dotc/profile/ThreadPoolFactory.scala
+++ b/compiler/src/dotty/tools/dotc/profile/ThreadPoolFactory.scala
@@ -94,9 +94,9 @@ object ThreadPoolFactory {
       val data = new ThreadProfileData
       localData.set(data)
 
-      val profileStart = profiler.snapThread(0)
+      val profileStart = RealProfiler.snapThread(0)
       try worker.run finally {
-        val snap = profiler.snapThread(data.idleNs)
+        val snap = RealProfiler.snapThread(data.idleNs)
         val threadRange = ProfileRange(profileStart, snap, phase, shortId, data.taskCount, Thread.currentThread())
         profiler.completeBackground(threadRange)
       }
diff --git a/compiler/src/dotty/tools/dotc/transform/Splicer.scala b/compiler/src/dotty/tools/dotc/transform/Splicer.scala
index e42f997e7265..b5386d5bd1df 100644
--- a/compiler/src/dotty/tools/dotc/transform/Splicer.scala
+++ b/compiler/src/dotty/tools/dotc/transform/Splicer.scala
@@ -47,13 +47,14 @@ object Splicer {
   def splice(tree: Tree, splicePos: SrcPos, spliceExpansionPos: SrcPos, classLoader: ClassLoader)(using Context): Tree = tree match {
     case Quote(quotedTree, Nil) => quotedTree
     case _ =>
-      val macroOwner = newSymbol(ctx.owner, nme.MACROkw, Macro | Synthetic, defn.AnyType, coord = tree.span)
+      val owner = ctx.owner
+      val macroOwner = newSymbol(owner, nme.MACROkw, Macro | Synthetic, defn.AnyType, coord = tree.span)
       try
         val sliceContext = SpliceScope.contextWithNewSpliceScope(splicePos.sourcePos).withOwner(macroOwner)
         inContext(sliceContext) {
           val oldContextClassLoader = Thread.currentThread().getContextClassLoader
           Thread.currentThread().setContextClassLoader(classLoader)
-          try {
+          try ctx.profiler.onMacroSplice(owner){
             val interpreter = new SpliceInterpreter(splicePos, classLoader)
 
             // Some parts of the macro are evaluated during the unpickling performed in quotedExprToTree
diff --git a/compiler/src/dotty/tools/dotc/typer/Implicits.scala b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
index c42b196b8dfb..0727c83d8469 100644
--- a/compiler/src/dotty/tools/dotc/typer/Implicits.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
@@ -1082,7 +1082,7 @@ trait Implicits:
    *                         it should be applied, EmptyTree otherwise.
    *  @param span            The position where errors should be reported.
    */
-  def inferImplicit(pt: Type, argument: Tree, span: Span)(using Context): SearchResult =
+  def inferImplicit(pt: Type, argument: Tree, span: Span)(using Context): SearchResult = ctx.profiler.onImplicitSearch(pt):
     trace(s"search implicit ${pt.show}, arg = ${argument.show}: ${argument.tpe.show}", implicits, show = true) {
       record("inferImplicit")
       assert(ctx.phase.allowsImplicitSearch,
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index 23855455e67b..3810bc66841e 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -2823,7 +2823,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
       case _ =>
         typed(rhs)
 
-  def typedValDef(vdef: untpd.ValDef, sym: Symbol)(using Context): Tree = {
+  def typedValDef(vdef: untpd.ValDef, sym: Symbol)(using Context): Tree = ctx.profiler.onTypedDef(sym) {
     val ValDef(name, tpt, _) = vdef
     checkNonRootName(vdef.name, vdef.nameSpan)
     completeAnnotations(vdef, sym)
@@ -2851,7 +2851,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
     sym.owner.info.decls.openForMutations.unlink(sym)
     EmptyTree
 
-  def typedDefDef(ddef: untpd.DefDef, sym: Symbol)(using Context): Tree = if !sym.info.exists then retractDefDef(sym) else {
+  def typedDefDef(ddef: untpd.DefDef, sym: Symbol)(using Context): Tree = if !sym.info.exists then retractDefDef(sym) else ctx.profiler.onTypedDef(sym) {
 
     // TODO: - Remove this when `scala.language.experimental.erasedDefinitions` is no longer experimental.
     //       - Modify signature to `erased def erasedValue[T]: T`
@@ -2963,7 +2963,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
     if !sym.is(Module) && !sym.isConstructor && sym.info.finalResultType.isErasedClass then
       sym.setFlag(Erased)
 
-  def typedTypeDef(tdef: untpd.TypeDef, sym: Symbol)(using Context): Tree = {
+  def typedTypeDef(tdef: untpd.TypeDef, sym: Symbol)(using Context): Tree = ctx.profiler.onTypedDef(sym) {
     val TypeDef(name, rhs) = tdef
     completeAnnotations(tdef, sym)
     val rhs1 = tdef.rhs match
@@ -2977,7 +2977,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
     assignType(cpy.TypeDef(tdef)(name, rhs1), sym)
   }
 
-  def typedClassDef(cdef: untpd.TypeDef, cls: ClassSymbol)(using Context): Tree = {
+  def typedClassDef(cdef: untpd.TypeDef, cls: ClassSymbol)(using Context): Tree = ctx.profiler.onTypedDef(cls) {
     if (!cls.info.isInstanceOf[ClassInfo]) return EmptyTree.assertingErrorsReported
 
     val TypeDef(name, impl @ Template(constr, _, self, _)) = cdef: @unchecked
diff --git a/compiler/src/dotty/tools/dotc/typer/TyperPhase.scala b/compiler/src/dotty/tools/dotc/typer/TyperPhase.scala
index 0c63f5b4ecb1..264d0f170769 100644
--- a/compiler/src/dotty/tools/dotc/typer/TyperPhase.scala
+++ b/compiler/src/dotty/tools/dotc/typer/TyperPhase.scala
@@ -43,7 +43,7 @@ class TyperPhase(addRootImports: Boolean = true) extends Phase {
   def typeCheck(using Context)(using subphase: SubPhase): Boolean = monitor(subphase.name) {
     val unit = ctx.compilationUnit
     try
-      if !unit.suspended then
+      if !unit.suspended then ctx.profiler.onUnit(ctx.phase, unit):
         unit.tpdTree = ctx.typer.typedExpr(unit.untpdTree)
         typr.println("typed: " + unit.source)
         record("retained untyped trees", unit.untpdTree.treeSize)
diff --git a/compiler/test/dotty/tools/dotc/profile/ChromeTraceTest.scala b/compiler/test/dotty/tools/dotc/profile/ChromeTraceTest.scala
new file mode 100644
index 000000000000..07dc53da1f83
--- /dev/null
+++ b/compiler/test/dotty/tools/dotc/profile/ChromeTraceTest.scala
@@ -0,0 +1,93 @@
+package dotty.tools.dotc.profile
+
+import java.io.*
+
+import org.junit.Assert.*
+import org.junit.*
+import java.nio.file.Files
+import java.nio.charset.StandardCharsets
+import java.util.concurrent.locks.LockSupport
+import scala.concurrent.duration.*
+
+class ChromeTraceTest:
+  private def testTraceOutputs(generator: ChromeTrace => Unit)(checkContent: PartialFunction[List[String], Unit]): Unit = {
+    val outfile = Files.createTempFile("trace-", ".json").nn
+    val tracer = new ChromeTrace(outfile)
+    try generator(tracer)
+    finally tracer.close()
+    val contentLines = scala.io.Source.fromFile(outfile.toFile().nn).getLines().toList
+    checkContent.applyOrElse(
+      contentLines,
+      content => fail(s"Invalid output lines: ${content.mkString(System.lineSeparator().nn)}")
+    )
+  }
+
+  @Test def traceCounterEvent(): Unit = testTraceOutputs{ tracer =>
+    tracer.traceCounterEvent("foo", "counter1", 42, processWide = true)
+    tracer.traceCounterEvent("bar", "counter2", 21, processWide = false)
+  }{
+    case """{"traceEvents":[""" ::
+        s"""{"cat":"scalac","name":"foo","ph":"C","tid":"${tid1}","pid":"${pid1}","ts":${ts1},"args":{"counter1":42}}""" ::
+        s""",{"cat":"scalac","name":"bar","ph":"C","tid":"${tid2}","pid":"${pid2}","ts":${ts2},"args":{"counter2":21}}""" ::
+           "]}" :: Nil =>
+      assertEquals(tid1, tid2)
+      assertTrue(tid1.toIntOption.isDefined)
+      assertNotEquals(pid1, pid2)
+      assertTrue(pid1.toIntOption.isDefined)
+      assertEquals(s"$pid1-$tid1", pid2)
+      assertTrue(ts1.toLong < ts2.toLong)
+  }
+
+  @Test def traceDurationEvent(): Unit = testTraceOutputs{ tracer =>
+    tracer.traceDurationEvent(name = "name1", startNanos = 1000L, durationNanos = 2500L,  tid = "this-thread")
+    tracer.traceDurationEvent(name = "name2", startNanos = 1000L, durationNanos = 5000L,  tid = "this-thread", pidSuffix = "pidSuffix")
+  }{
+    case """{"traceEvents":[""" ::
+        s"""{"cat":"scalac","name":"name1","ph":"X","tid":"this-thread","pid":"${pid1}","ts":1,"dur":2}""" ::
+        s""",{"cat":"scalac","name":"name2","ph":"X","tid":"this-thread","pid":"${pid2}","ts":1,"dur":5}""" ::
+           "]}" :: Nil =>
+      assertTrue(pid1.toIntOption.isDefined)
+      assertEquals(s"$pid1-pidSuffix", pid2)
+  }
+
+  @Test def traceDurationEvents(): Unit = {
+    val testStart = System.nanoTime()
+    testTraceOutputs{ tracer =>
+    tracer.traceDurationEventStart(cat = "test1", name = "event1")
+    LockSupport.parkNanos(2.millis.toNanos)
+    tracer.traceDurationEventStart(cat = "test2", name = "event2", colour = "RED", pidSuffix = "pid-suffix")
+    LockSupport.parkNanos(4.millis.toNanos)
+    tracer.traceDurationEventEnd(cat = "test2", name = "event2")
+    LockSupport.parkNanos(8.millis.toNanos)
+    tracer.traceDurationEventEnd(cat = "test1", name = "event1", colour = "RED", pidSuffix = "pid-suffix")
+  }{
+    case """{"traceEvents":[""" ::
+        s"""{"cat":"test1","name":"event1","ph":"B","pid":"${pid1}","tid":"${tid1}","ts":${ts1}}""" ::
+        s""",{"cat":"test2","name":"event2","ph":"B","pid":"${pid2}","tid":"${tid2}","ts":${ts2},"cname":"RED"}""" ::
+        s""",{"cat":"test2","name":"event2","ph":"E","pid":"${pid3}","tid":"${tid3}","ts":${ts3}}""" ::
+        s""",{"cat":"test1","name":"event1","ph":"E","pid":"${pid4}","tid":"${tid4}","ts":${ts4},"cname":"RED"}""" ::
+           "]}" :: Nil =>
+      val traceEnd = System.nanoTime()
+      assertTrue(tid1.toIntOption.isDefined)
+      assertEquals(pid1, pid3)
+      assertTrue(pid1.endsWith(s"-$tid1"))
+      assertEquals(pid2, pid4)
+      assertTrue(pid2.endsWith("-pid-suffix"))
+      List(tid1, tid2, tid3).foreach: tid =>
+        assertEquals(tid4, tid)
+      List(pid1, pid2, pid3, pid4).foreach: pid =>
+        assertTrue(pid.takeWhile(_ != '-').toIntOption.isDefined)
+
+      List(ts1, ts2, ts3, ts4).map(_.toLong) match {
+        case all @ List(ts1, ts2, ts3, ts4) =>
+          all.foreach: ts =>
+            // Timestamps are presented using Epoch microsecondos
+            assertTrue(ts >= testStart / 1000)
+            assertTrue(ts <= traceEnd / 1000)
+          assertTrue(ts2 >= ts1 + 2.millis.toMicros)
+          assertTrue(ts3 >= ts2 + 4.millis.toMicros)
+          assertTrue(ts4 >= ts3 + 8.millis.toMicros)
+        case _ => fail("unreachable")
+      }
+  }
+}
diff --git a/compiler/test/dotty/tools/dotc/profile/FileUtilsTest.scala b/compiler/test/dotty/tools/dotc/profile/FileUtilsTest.scala
new file mode 100644
index 000000000000..3253cff52057
--- /dev/null
+++ b/compiler/test/dotty/tools/dotc/profile/FileUtilsTest.scala
@@ -0,0 +1,91 @@
+package dotty.tools.dotc.profile
+
+import java.io.*
+
+import org.junit.Assert.*
+import org.junit.*
+
+class FileUtilsTest {
+
+  @Test def writeIsSame(): Unit = {
+    val fileTest = File.createTempFile("FileUtilsTest", "t1").nn
+    val fileExpected = File.createTempFile("FileUtilsTest", "t2").nn
+
+    val sTest = FileUtils.newAsyncBufferedWriter(new FileWriter(fileTest), threadsafe = false)
+    val sExpected = new BufferedWriter(new FileWriter(fileExpected))
+
+    def writeBoth(s:String, asChars: Boolean) = {
+      if (asChars) {
+        sTest.write(s.toCharArray)
+        sExpected.write(s.toCharArray)
+      } else {
+        sTest.write(s)
+        sExpected.write(s)
+      }
+    }
+
+    for (i <- 1 to 2000) {
+      writeBoth(s"line $i text;", asChars = true)
+      writeBoth(s"line $i chars", asChars = false)
+      sTest.newLine()
+      sExpected.newLine()
+    }
+    sTest.close()
+    sExpected.close()
+
+    assertEquals(fileExpected.length(),fileTest.length())
+
+    val expIn = new BufferedReader(new FileReader(fileExpected))
+    val testIn = new BufferedReader(new FileReader(fileTest))
+
+    var exp = expIn.readLine()
+    while (exp ne null) {
+      val actual = testIn.readLine()
+      assertEquals(exp, actual)
+      exp = expIn.readLine()
+    }
+    expIn.close()
+    testIn.close()
+    fileTest.delete()
+    fileExpected.delete()
+  }
+
+  @Ignore
+  @Test def showPerformance(): Unit = {
+    //warmup
+    for (i <- 1 to 1000) {
+      writeIsSame()
+    }
+
+    val fileTest = File.createTempFile("FileUtilsTest", "t1").nn
+    val fileExpected = File.createTempFile("FileUtilsTest", "t2").nn
+
+    for (i <- 1 to 10) {
+      val sTest = FileUtils.newAsyncBufferedWriter(fileTest.toPath.nn)
+      val sExpected = new BufferedWriter(new FileWriter(fileExpected))
+
+      val t1 = System.nanoTime()
+      List.tabulate(10000) {i =>
+        sTest.write(s"line $i text;")
+        sTest.newLine()
+      }
+      val t2 = System.nanoTime()
+      sTest.close()
+      val t3 = System.nanoTime()
+      List.tabulate(10000) {i =>
+        sExpected.write(s"line $i text;")
+        sExpected.newLine()
+      }
+      val t4 = System.nanoTime()
+      sExpected.close()
+
+      println(s"async    took ${t2 - t1} ns")
+      println(s"buffered took ${t4 - t3} ns")
+
+      fileTest.delete()
+      fileExpected.delete()
+    }
+  }
+
+}
+
diff --git a/presentation-compiler/src/main/dotty/tools/pc/completions/CompletionProvider.scala b/presentation-compiler/src/main/dotty/tools/pc/completions/CompletionProvider.scala
index 5578fab412d1..adaeadb12978 100644
--- a/presentation-compiler/src/main/dotty/tools/pc/completions/CompletionProvider.scala
+++ b/presentation-compiler/src/main/dotty/tools/pc/completions/CompletionProvider.scala
@@ -21,6 +21,7 @@ import dotty.tools.dotc.interactive.Interactive
 import dotty.tools.dotc.interactive.Completion
 import dotty.tools.dotc.interactive.InteractiveDriver
 import dotty.tools.dotc.parsing.Tokens
+import dotty.tools.dotc.profile.Profiler
 import dotty.tools.dotc.util.SourceFile
 import dotty.tools.pc.AutoImports.AutoImportEdits
 import dotty.tools.pc.AutoImports.AutoImportsGenerator
@@ -75,7 +76,10 @@ class CompletionProvider(
     val pos = driver.sourcePosition(params)
     val (items, isIncomplete) = driver.compilationUnits.get(uri) match
       case Some(unit) =>
-        val newctx = ctx.fresh.setCompilationUnit(unit).withPhase(Phases.typerPhase(using ctx))
+        val newctx = ctx.fresh
+          .setCompilationUnit(unit)
+          .setProfiler(Profiler()(using ctx))
+          .withPhase(Phases.typerPhase(using ctx))
         val tpdPath0 = Interactive.pathTo(unit.tpdTree, pos.span)(using newctx)
         val adjustedPath = Interactive.resolveTypedOrUntypedPath(tpdPath0, pos)(using newctx)
 

From f7f51edb424b281f751a9a47ea2397d5cf5b0343 Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Wed, 23 Oct 2024 10:46:09 +0200
Subject: [PATCH 37/39] Don't warn for deprecated Thread.getId() calls in
 `ChromeTrace` (#21831)

---
 compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala | 1 +
 1 file changed, 1 insertion(+)

diff --git a/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala b/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala
index c33039f46398..4950f439640f 100644
--- a/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala
+++ b/compiler/src/dotty/tools/dotc/profile/ChromeTrace.scala
@@ -45,6 +45,7 @@ final class ChromeTrace(f: Path) extends Closeable {
   private val traceWriter = FileUtils.newAsyncBufferedWriter(f)
   private val context = mutable.Stack[JsonContext](TopContext)
   private val tidCache = new ThreadLocal[String]() {
+    @annotation.nowarn("cat=deprecation")
     override def initialValue(): String = "%05d".format(Thread.currentThread().getId())
   }
   objStart()

From 15922f93c59dc0ae60ae1b26362962b0b5c04921 Mon Sep 17 00:00:00 2001
From: Dale Wijnand <dale.wijnand@gmail.com>
Date: Wed, 21 Aug 2024 16:06:44 +0100
Subject: [PATCH 38/39] Fix enclosingClass from returning refinement classes

Looking at how i20952 is compiled, the call

    ctx.owner.enclosingClass.derivesFrom(sym.owner)

in SuperAccessors (that I moved to ProtectedAccessors) accidentally
fails, because the refinement class returned as the enclosing class of
`val prog` doesn't derive from SuperClass.  But if the enclosing class
of `prog` returned is `trait Child` then no super accessor call is
necessary.
---
 .../tools/dotc/core/SymDenotations.scala      |  6 +++---
 .../dotc/transform/ProtectedAccessors.scala   |  5 ++++-
 .../tools/dotc/transform/SuperAccessors.scala |  2 +-
 tests/pos/i20952.scala                        | 20 +++++++++++++++++++
 4 files changed, 28 insertions(+), 5 deletions(-)
 create mode 100644 tests/pos/i20952.scala

diff --git a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
index 906e74735097..f54b8a62fa25 100644
--- a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -1162,10 +1162,10 @@ object SymDenotations {
     final def enclosingClass(using Context): Symbol = {
       def enclClass(sym: Symbol, skip: Boolean): Symbol = {
         def newSkip = sym.is(JavaStaticTerm)
-        if (!sym.exists)
+        if !sym.exists then
           NoSymbol
-        else if (sym.isClass)
-          if (skip) enclClass(sym.owner, newSkip) else sym
+        else if sym.isClass then
+          if skip || sym.isRefinementClass then enclClass(sym.owner, newSkip) else sym
         else
           enclClass(sym.owner, skip || newSkip)
       }
diff --git a/compiler/src/dotty/tools/dotc/transform/ProtectedAccessors.scala b/compiler/src/dotty/tools/dotc/transform/ProtectedAccessors.scala
index 482da0edb82b..359ec701d164 100644
--- a/compiler/src/dotty/tools/dotc/transform/ProtectedAccessors.scala
+++ b/compiler/src/dotty/tools/dotc/transform/ProtectedAccessors.scala
@@ -44,7 +44,10 @@ object ProtectedAccessors {
   /** Do we need a protected accessor for accessing sym from the current context's owner? */
   def needsAccessor(sym: Symbol)(using Context): Boolean =
     needsAccessorIfNotInSubclass(sym) &&
-    !ctx.owner.enclosingClass.derivesFrom(sym.owner)
+    !needsAccessorIsSubclass(sym)
+
+  def needsAccessorIsSubclass(sym: Symbol)(using Context): Boolean =
+    ctx.owner.enclosingClass.derivesFrom(sym.owner)
 }
 
 class ProtectedAccessors extends MiniPhase {
diff --git a/compiler/src/dotty/tools/dotc/transform/SuperAccessors.scala b/compiler/src/dotty/tools/dotc/transform/SuperAccessors.scala
index ce2b8fa591d8..5a63235fc3c0 100644
--- a/compiler/src/dotty/tools/dotc/transform/SuperAccessors.scala
+++ b/compiler/src/dotty/tools/dotc/transform/SuperAccessors.scala
@@ -195,7 +195,7 @@ class SuperAccessors(thisPhase: DenotTransformer) {
          * Otherwise, we need to go through an accessor,
          * which the implementing class will provide an implementation for.
          */
-        if ctx.owner.enclosingClass.derivesFrom(sym.owner) then
+        if ProtectedAccessors.needsAccessorIsSubclass(sym) then
           if sym.is(JavaDefined) then
             report.error(em"${ctx.owner} accesses protected $sym inside a concrete trait method: use super.${sel.name} instead", sel.srcPos)
           sel
diff --git a/tests/pos/i20952.scala b/tests/pos/i20952.scala
new file mode 100644
index 000000000000..68344fdab672
--- /dev/null
+++ b/tests/pos/i20952.scala
@@ -0,0 +1,20 @@
+package object packer: // the super class needs to be in a different package
+  class SuperClass():
+    protected val problem: Any = ??? // needs to be protected
+
+class SuperClass():
+  protected val problem: Any = ??? // needs to be protected
+
+// type Target = SuperClass        // passes
+type Target = packer.SuperClass // error
+
+trait Child extends Target:
+
+  val aliased: problem.type = problem
+  type Alias = problem.type
+
+  val newProblem: Any {val prog: problem.type} = ???  // error
+  val newProblem2: Any {val prog: Alias} = ???         // passes
+  val newProblem3: Any {val prog: aliased.type} = ???  // passes
+
+class ChildImpl extends Target with Child // concrete implementation is needed

From 641b67a0ce50ae52cc401ea3855bd4bac9ab4622 Mon Sep 17 00:00:00 2001
From: Wojciech Mazur <wmazur@virtuslab.com>
Date: Wed, 23 Oct 2024 23:22:44 +0200
Subject: [PATCH 39/39] Add minimal set of tests for runner installed from .msi
 file (#21835)

Add minimal set of tests to check installation of Scala runner from .msi
file.
---
 .github/workflows/ci.yaml      | 10 ++++-
 .github/workflows/test-msi.yml | 77 ++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+), 1 deletion(-)
 create mode 100644 .github/workflows/test-msi.yml

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 91086858c514..ffa7e515b926 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -1119,7 +1119,15 @@ jobs:
   build-msi-package:
     uses: ./.github/workflows/build-msi.yml
     if  : github.event_name == 'pull_request' && contains(github.event.pull_request.body, '[test_msi]')
-    # TODO: ADD A JOB THAT DEPENDS ON THIS TO TEST THE MSI
+
+  test-msi-package:
+    uses: ./.github/workflows/test-msi.yml
+    needs: [build-msi-package]
+    with:
+      # Ensure that version starts with prefix 3.
+      # In the future it can be adapted to compare with with git tag or version set in the build.s 
+      version: "3."
+      java-version: 8
 
   build-sdk-package:
     uses: ./.github/workflows/build-sdk.yml
diff --git a/.github/workflows/test-msi.yml b/.github/workflows/test-msi.yml
new file mode 100644
index 000000000000..1299c3d55061
--- /dev/null
+++ b/.github/workflows/test-msi.yml
@@ -0,0 +1,77 @@
+###################################################################################################
+###                  THIS IS A REUSABLE WORKFLOW TO TEST SCALA WITH MSI RUNNER                  ###
+### HOW TO USE:                                                                                 ###
+###  Provide optional `version` to test if installed binaries are installed with                ###
+###  correct Scala version.                                                                     ###
+### NOTE: Requires `scala.msi` artifact uploaded within the same run                            ###
+###                                                                                             ###
+###################################################################################################
+
+name: Test 'scala' MSI Package
+run-name: Test 'scala' (${{ inputs.version }}) MSI Package
+
+on:
+  workflow_call:
+    inputs:
+      version:
+        required: true
+        type: string
+      java-version:
+        required: true
+        type    : string
+
+jobs:
+  test:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: ${{ inputs.java-version }}
+      - name: Download MSI artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: scala.msi
+          path: .
+
+      # Run the MSI installer
+      # During normal installation msiexec would modify the PATH automatically. 
+      # However, it seems not to work in GH Actions. Append the PATH manually instead.
+      - name: Install Scala Runner
+        shell: pwsh
+        run: |
+          Start-Process 'msiexec.exe' -ArgumentList '/I "scala.msi" /L*V "install.log" /qb' -Wait
+          Get-Content 'install.log'
+          Add-Content $env:GITHUB_PATH "C:\Program Files (x86)\scala\bin"
+
+      # Run tests to ensure the Scala Runner was installed and works
+      - name: Test Scala Runner
+        shell: pwsh
+        run: |
+          scala --version
+          if (-not (scala --version | Select-String "Scala version \(default\): ${{ inputs.version }}")) {
+            Write-Host "Invalid Scala version of MSI installed runner, expected ${{ inputs.version }}"
+            Exit 1
+          }
+      - name : Test the `scalac` command
+        shell: pwsh
+        run: |
+          scalac --version
+          if (-not (scalac --version | Select-String "Scala compiler version ${{ inputs.version }}")) {
+            Write-Host "Invalid scalac version of MSI installed runner, expected ${{ inputs.version }}"
+            Exit 1
+          }
+      - name : Test the `scaladoc` command
+        shell: pwsh
+        run: |
+          scaladoc --version
+          if (-not (scaladoc --version | Select-String "Scaladoc version ${{ inputs.version }}")) {
+            Write-Host "Invalid scaladoc version of MSI installed runner, expected ${{ inputs.version }}"
+            Exit 1
+          }
+      - name : Uninstall the `scala` package
+        shell: pwsh
+        run: |
+          Start-Process 'msiexec.exe' -ArgumentList '/X "scala.msi" /L*V "uninstall.log" /qb' -Wait
+          Get-Content 'uninstall.log'
+        
\ No newline at end of file