Change owner as necessary when typing a TypedSplice

When typing an untpd.TypedSplice it could be that the owner
at the time the tree is originally typed is different from the owner
at the time the tree is unwrapped. In that case the owner needs
to be changed.

Problem was noticed in Course-2002-02 after changing Closure to
be a pure expression. This means that TypedSplices containing
closures are no longer lifted out from containing closures
during eta expansion, and the owner chain got corrupted.

1 files changed, 8 insertions, 3 deletions

diff --git a/src/dotty/tools/dotc/ast/untpd.scala b/src/dotty/tools/dotc/ast/untpd.scala
index 114c13684..a0a353c13 100644
--- a/src/dotty/tools/dotc/ast/untpd.scala
+++ b/src/dotty/tools/dotc/ast/untpd.scala
@@ -21,10 +21,15 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
   }
 
   /** A typed subtree of an untyped tree needs to be wrapped in a TypedSlice */
-  case class TypedSplice(tree: tpd.Tree) extends ProxyTree {
+  abstract case class TypedSplice(tree: tpd.Tree)(val owner: Symbol) extends ProxyTree {
     def forwardTo = tree
   }
 
+  object TypedSplice {
+    def apply(tree: tpd.Tree)(implicit ctx: Context): TypedSplice =
+      new TypedSplice(tree)(ctx.owner) {}
+  }
+
   /** mods object name impl */
   case class ModuleDef(name: TermName, impl: Template)
     extends MemberDef {
@@ -232,7 +237,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
       case AppliedTypeTree(tycon, targs) =>
         (tycon, targs)
       case TypedSplice(AppliedTypeTree(tycon, targs)) =>
-        (TypedSplice(tycon), targs map TypedSplice)
+        (TypedSplice(tycon), targs map (TypedSplice(_)))
       case TypedSplice(tpt1: Tree) =>
         val argTypes = tpt1.tpe.argTypes
         val tycon = tpt1.tpe.withoutArgs(argTypes)
@@ -260,7 +265,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
   def AppliedTypeTree(tpt: Tree, arg: Tree): AppliedTypeTree =
     AppliedTypeTree(tpt, arg :: Nil)
 
-  def TypeTree(tpe: Type): TypedSplice = TypedSplice(TypeTree().withTypeUnchecked(tpe))
+  def TypeTree(tpe: Type)(implicit ctx: Context): TypedSplice = TypedSplice(TypeTree().withTypeUnchecked(tpe))
 
   def TypeDef(name: TypeName, tparams: List[TypeDef], rhs: Tree): TypeDef =
     if (tparams.isEmpty) TypeDef(name, rhs) else new PolyTypeDef(name, tparams, rhs)