Merge branch 'master' into argument-file-fix-13552

Author: philwalk

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

@@ -56,9 +56,6 @@ class CompilationUnit protected (val source: SourceFile) {
    */
   var needsQuotePickling: Boolean = false
 
-  /** A structure containing a temporary map for generating inline accessors */
-  val inlineAccessors: InlineAccessors = new InlineAccessors
-
   var suspended: Boolean = false
   var suspendedAtInliningPhase: Boolean = false
 

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

@@ -113,11 +113,11 @@ trait TreeInfo[T >: Untyped <: Type] { self: Trees.Instance[T] =>
     case _ => 0
   }
 
-  /** The (last) list of arguments of an application */
-  def arguments(tree: Tree): List[Tree] = unsplice(tree) match {
-    case Apply(_, args) => args
-    case TypeApply(fn, _) => arguments(fn)
-    case Block(_, expr) => arguments(expr)
+  /** All term arguments of an application in a single flattened list */
+  def allArguments(tree: Tree): List[Tree] = unsplice(tree) match {
+    case Apply(fn, args) => allArguments(fn) ::: args
+    case TypeApply(fn, _) => allArguments(fn)
+    case Block(_, expr) => allArguments(expr)
     case _ => Nil
   }
 

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

@@ -7,14 +7,17 @@ import StdNames._
 import dotty.tools.dotc.ast.tpd
 import scala.util.Try
 import util.Spans.Span
+import printing.{Showable, Printer}
+import printing.Texts.Text
+import annotation.internal.sharable
 
 object Annotations {
 
   def annotClass(tree: Tree)(using Context) =
     if (tree.symbol.isConstructor) tree.symbol.owner
     else tree.tpe.typeSymbol
 
-  abstract class Annotation {
+  abstract class Annotation extends Showable {
     def tree(using Context): Tree
 
     def symbol(using Context): Symbol = annotClass(tree)
@@ -26,7 +29,8 @@ object Annotations {
     def derivedAnnotation(tree: Tree)(using Context): Annotation =
       if (tree eq this.tree) this else Annotation(tree)
 
-    def arguments(using Context): List[Tree] = ast.tpd.arguments(tree)
+    /** All arguments to this annotation in a single flat list */
+    def arguments(using Context): List[Tree] = ast.tpd.allArguments(tree)
 
     def argument(i: Int)(using Context): Option[Tree] = {
       val args = arguments
@@ -44,15 +48,48 @@ object Annotations {
     /** The tree evaluation has finished. */
     def isEvaluated: Boolean = true
 
+    /** Normally, type map over all tree nodes of this annotation, but can
+     *  be overridden. Returns EmptyAnnotation if type type map produces a range
+     *  type, since ranges cannot be types of trees.
+     */
+    def mapWith(tm: TypeMap)(using Context) =
+      val args = arguments
+      if args.isEmpty then this
+      else
+        val findDiff = new TreeAccumulator[Type]:
+          def apply(x: Type, tree: Tree)(using Context): Type =
+            if tm.isRange(x) then x
+            else
+              val tp1 = tm(tree.tpe)
+              foldOver(if tp1 =:= tree.tpe then x else tp1, tree)
+        val diff = findDiff(NoType, args)
+        if tm.isRange(diff) then EmptyAnnotation
+        else if diff.exists then derivedAnnotation(tm.mapOver(tree))
+        else this
+
+    /** Does this annotation refer to a parameter of `tl`? */
+    def refersToParamOf(tl: TermLambda)(using Context): Boolean =
+      val args = arguments
+      if args.isEmpty then false
+      else tree.existsSubTree {
+        case id: Ident => id.tpe match
+          case TermParamRef(tl1, _) => tl eq tl1
+          case _ => false
+        case _ => false
+      }
+
+    /** A string representation of the annotation. Overridden in BodyAnnotation.
+     */
+    def toText(printer: Printer): Text = printer.annotText(this)
+
     def ensureCompleted(using Context): Unit = tree
 
     def sameAnnotation(that: Annotation)(using Context): Boolean =
       symbol == that.symbol && tree.sameTree(that.tree)
   }
 
-  case class ConcreteAnnotation(t: Tree) extends Annotation {
+  case class ConcreteAnnotation(t: Tree) extends Annotation:
     def tree(using Context): Tree = t
-  }
 
   abstract class LazyAnnotation extends Annotation {
     protected var mySym: Symbol | (Context ?=> Symbol)
@@ -98,6 +135,7 @@ object Annotations {
       if (tree eq this.tree) this else ConcreteBodyAnnotation(tree)
     override def arguments(using Context): List[Tree] = Nil
     override def ensureCompleted(using Context): Unit = ()
+    override def toText(printer: Printer): Text = "@Body"
   }
 
   class ConcreteBodyAnnotation(body: Tree) extends BodyAnnotation {
@@ -194,6 +232,8 @@ object Annotations {
       apply(defn.SourceFileAnnot, Literal(Constant(path)))
   }
 
+  @sharable val EmptyAnnotation = Annotation(EmptyTree)
+
   def ThrowsAnnotation(cls: ClassSymbol)(using Context): Annotation = {
     val tref = cls.typeRef
     Annotation(defn.ThrowsAnnot.typeRef.appliedTo(tref), Ident(tref))

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

@@ -2526,17 +2526,6 @@ class TypeComparer(@constructorOnly initctx: Context) extends ConstraintHandling
         case _ => false
       })
 
-    /** Can we enumerate all instantiations of this type? */
-    def isClosedSum(tp: Symbol): Boolean =
-      tp.is(Sealed) && tp.isOneOf(AbstractOrTrait) && !tp.hasAnonymousChild
-
-    /** Splits a closed type into a disjunction of smaller types.
-     *  It should hold that `tp` and `decompose(tp).reduce(_ or _)`
-     *  denote the same set of values.
-     */
-    def decompose(sym: Symbol, tp: Type): List[Type] =
-      sym.children.map(x => refineUsingParent(tp, x)).filter(_.exists)
-
     def fullyInstantiated(tp: Type): Boolean = new TypeAccumulator[Boolean] {
       override def apply(x: Boolean, t: Type) =
         x && {
@@ -2558,6 +2547,10 @@ class TypeComparer(@constructorOnly initctx: Context) extends ConstraintHandling
       case (tp1: TypeRef, tp2: TypeRef) if tp1.symbol.isClass && tp2.symbol.isClass =>
         val cls1 = tp1.classSymbol
         val cls2 = tp2.classSymbol
+        def isDecomposable(tp: Symbol): Boolean =
+           tp.is(Sealed) && !tp.hasAnonymousChild
+        def decompose(sym: Symbol, tp: Type): List[Type] =
+          sym.children.map(x => refineUsingParent(tp, x)).filter(_.exists)
         if (cls1.derivesFrom(cls2) || cls2.derivesFrom(cls1))
           false
         else
@@ -2570,9 +2563,13 @@ class TypeComparer(@constructorOnly initctx: Context) extends ConstraintHandling
             // subtype, so they must be unrelated by single inheritance
             // of classes.
             true
-          else if (isClosedSum(cls1))
+          else if (isDecomposable(cls1))
+            // At this point, !cls1.derivesFrom(cls2): we know that direct
+            // instantiations of `cls1` (terms of the form `new cls1`) are not
+            // of type `tp2`. Therefore, we can safely decompose `cls1` using
+            // `.children`, even if `cls1` is non abstract.
             decompose(cls1, tp1).forall(x => provablyDisjoint(x, tp2))
-          else if (isClosedSum(cls2))
+          else if (isDecomposable(cls2))
             decompose(cls2, tp2).forall(x => provablyDisjoint(x, tp1))
           else
             false

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

@@ -164,9 +164,13 @@ object TypeOps:
         // with Nulls (which have no base classes). Under -Yexplicit-nulls, we take
         // corrective steps, so no widening is wanted.
         simplify(l, theMap) | simplify(r, theMap)
-      case AnnotatedType(parent, annot)
-      if annot.symbol == defn.UncheckedVarianceAnnot && !ctx.mode.is(Mode.Type) && !theMap.isInstanceOf[SimplifyKeepUnchecked] =>
-        simplify(parent, theMap)
+      case tp @ AnnotatedType(parent, annot) =>
+        val parent1 = simplify(parent, theMap)
+        if annot.symbol == defn.UncheckedVarianceAnnot
+            && !ctx.mode.is(Mode.Type)
+            && !theMap.isInstanceOf[SimplifyKeepUnchecked]
+        then parent1
+        else tp.derivedAnnotatedType(parent1, annot)
       case _: MatchType =>
         val normed = tp.tryNormalize
         if (normed.exists) normed else mapOver

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

@@ -1389,6 +1389,17 @@ object Types {
     /** Like `dealiasKeepAnnots`, but keeps only refining annotations */
     final def dealiasKeepRefiningAnnots(using Context): Type = dealias1(keepIfRefining)
 
+    /** Approximate this type with a type that does not contain skolem types. */
+    final def deskolemized(using Context): Type =
+      val deskolemizer = new ApproximatingTypeMap {
+        def apply(tp: Type) = /*trace(i"deskolemize($tp) at $variance", show = true)*/
+          tp match {
+            case tp: SkolemType => range(defn.NothingType, atVariance(1)(apply(tp.info)))
+            case _ => mapOver(tp)
+          }
+      }
+      deskolemizer(this)
+
     /** The result of normalization using `tryNormalize`, or the type itself if
      *  tryNormlize yields NoType
      */
@@ -3601,6 +3612,9 @@ object Types {
           case tp: AppliedType => tp.fold(status, compute(_, _, theAcc))
           case tp: TypeVar if !tp.isInstantiated => combine(status, Provisional)
           case tp: TermParamRef if tp.binder eq thisLambdaType => TrueDeps
+          case AnnotatedType(parent, ann) =>
+            if ann.refersToParamOf(thisLambdaType) then TrueDeps
+            else compute(status, parent, theAcc)
           case _: ThisType | _: BoundType | NoPrefix => status
           case _ =>
             (if theAcc != null then theAcc else DepAcc()).foldOver(status, tp)
@@ -3653,8 +3667,10 @@ object Types {
       if (isResultDependent) {
         val dropDependencies = new ApproximatingTypeMap {
           def apply(tp: Type) = tp match {
-            case tp @ TermParamRef(thisLambdaType, _) =>
+            case tp @ TermParamRef(`thisLambdaType`, _) =>
               range(defn.NothingType, atVariance(1)(apply(tp.underlying)))
+            case AnnotatedType(parent, ann) if ann.refersToParamOf(thisLambdaType) =>
+              mapOver(parent)
             case _ => mapOver(tp)
           }
         }
@@ -4104,18 +4120,17 @@ object Types {
 
     override def underlying(using Context): Type = tycon
 
-    override def superType(using Context): Type = {
-      if (ctx.period != validSuper) {
-        cachedSuper = tycon match {
+    override def superType(using Context): Type =
+      if ctx.period != validSuper then
+        validSuper = if (tycon.isProvisional) Nowhere else ctx.period
+        cachedSuper = tycon match
           case tycon: HKTypeLambda => defn.AnyType
           case tycon: TypeRef if tycon.symbol.isClass => tycon
-          case tycon: TypeProxy => tycon.superType.applyIfParameterized(args)
+          case tycon: TypeProxy =>
+            if isMatchAlias then validSuper = Nowhere
+            tycon.superType.applyIfParameterized(args).normalized
           case _ => defn.AnyType
-        }
-        validSuper = if (tycon.isProvisional) Nowhere else ctx.period
-      }
       cachedSuper
-    }
 
     override def translucentSuperType(using Context): Type = tycon match {
       case tycon: TypeRef if tycon.symbol.isOpaqueAlias =>
@@ -5379,6 +5394,8 @@ object Types {
       variance = saved
       derivedLambdaType(tp)(ptypes1, this(restpe))
 
+    def isRange(tp: Type): Boolean = tp.isInstanceOf[Range]
+
     /** Map this function over given type */
     def mapOver(tp: Type): Type = {
       record(s"TypeMap mapOver ${getClass}")
@@ -5422,8 +5439,9 @@ object Types {
 
         case tp @ AnnotatedType(underlying, annot) =>
           val underlying1 = this(underlying)
-          if (underlying1 eq underlying) tp
-          else derivedAnnotatedType(tp, underlying1, mapOver(annot))
+          val annot1 = annot.mapWith(this)
+          if annot1 eq EmptyAnnotation then underlying1
+          else derivedAnnotatedType(tp, underlying1, annot1)
 
         case _: ThisType
           | _: BoundType
@@ -5495,9 +5513,6 @@ object Types {
       else newScopeWith(elems1: _*)
     }
 
-    def mapOver(annot: Annotation): Annotation =
-      annot.derivedAnnotation(mapOver(annot.tree))
-
     def mapOver(tree: Tree): Tree = treeTypeMap(tree)
 
     /** Can be overridden. By default, only the prefix is mapped. */
@@ -5544,8 +5559,6 @@ object Types {
 
     protected def emptyRange = range(defn.NothingType, defn.AnyType)
 
-    protected def isRange(tp: Type): Boolean = tp.isInstanceOf[Range]
-
     protected def lower(tp: Type): Type = tp match {
       case tp: Range => tp.lo
       case _ => tp

compiler/src/dotty/tools/dotc/printing/PlainPrinter.scala

@@ -404,6 +404,10 @@ class PlainPrinter(_ctx: Context) extends Printer {
       case tp: ExprType =>
         // parameterless methods require special treatment, see #11201
         (if (isParameter) ": => " else ": ") ~ toTextGlobal(tp.widenExpr)
+      case tp: PolyType =>
+        "[" ~ paramsText(tp) ~ "]"
+        ~ (Str(": ") provided !tp.resultType.isInstanceOf[MethodType])
+        ~ toTextGlobal(tp.resultType)
       case tp =>
         ": " ~ toTextGlobal(tp)
     }
@@ -539,7 +543,10 @@ class PlainPrinter(_ctx: Context) extends Printer {
     case _ => literalText(String.valueOf(const.value))
   }
 
-  def toText(annot: Annotation): Text = s"@${annot.symbol.name}" // for now
+  /** Usual target for `Annotation#toText`, overridden in RefinedPrinter */
+  def annotText(annot: Annotation): Text = s"@${annot.symbol.name}"
+
+  def toText(annot: Annotation): Text = annot.toText(this)
 
   def toText(param: LambdaParam): Text =
     varianceSign(param.paramVariance)
@@ -570,7 +577,7 @@ class PlainPrinter(_ctx: Context) extends Printer {
         Text()
 
     nodeName ~ "(" ~ elems ~ tpSuffix ~ ")" ~ (Str(tree.sourcePos.toString) provided printDebug)
-  }.close // todo: override in refined printer
+  }.close
 
   def toText(pos: SourcePosition): Text =
     if (!pos.exists) "<no position>"

compiler/src/dotty/tools/dotc/printing/Printer.scala

@@ -119,6 +119,9 @@ abstract class Printer {
   /** A description of sym's location */
   def extendedLocationText(sym: Symbol): Text
 
+  /** Textual description of regular annotation in terms of its tree */
+  def annotText(annot: Annotation): Text
+
   /** Textual representation of denotation */
   def toText(denot: Denotation): Text