Shadowed references

In TypeAssigner#ensureAccible we sometimes pick an inherited public
member as the denotation of a NamedType instead of an inaccessible
private one. The problem is that both are denotations for the same type,
which caused a noDoubleBindings assert failure. We now solve this problem
by creating a "shadowed" named type to hold the inherited member.

The shadowed named type is distinguished by its name, which reads

    (inherited)originalName

In the future, we should make this more robust by using a general
tagging scheme to create shadowed names.

Another fix is about import symbols. They are now referenced with
NonMemberTermRefs. With this fix, the test suite passes with no
double def violations.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/dotty/tools/dotc/typer/TypeAssigner.scala b/src/dotty/tools/dotc/typer/TypeAssigner.scala
index b194bdd60..12f2415d8 100644
--- a/src/dotty/tools/dotc/typer/TypeAssigner.scala
+++ b/src/dotty/tools/dotc/typer/TypeAssigner.scala
@@ -110,7 +110,7 @@ trait TypeAssigner {
           // an inherited non-private member with the same name and signature.
           val d2 = pre.nonPrivateMember(name)
           if (reallyExists(d2) && firstTry)
-            test(pre.select(name, d2), false)
+            test(tpe.shadowed.withDenot(d2), false)
           else {
             val alts = tpe.denot.alternatives.map(_.symbol).filter(_.exists)
             val what = alts match {
@@ -326,7 +326,7 @@ trait TypeAssigner {
     tree.withType(sym.typeRef)
 
   def assignType(tree: untpd.Import, sym: Symbol)(implicit ctx: Context) =
-    tree.withType(sym.termRef)
+    tree.withType(sym.nonMemberTermRef)
 
   def assignType(tree: untpd.Annotated, annot: Tree, arg: Tree)(implicit ctx: Context) =
     tree.withType(AnnotatedType(Annotation(annot), arg.tpe))