Don't skip package objects as owners in typedIdent

The previous treatment would be incompatible with the new opaque types scheme.

Author: odersky

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -278,12 +278,17 @@ class Typer extends Namer
           // with the exact list of files given).
           val isNewDefScope =
             if (curOwner.is(Package) && !curOwner.isRoot) curOwner ne ctx.outer.owner
-            else ((ctx.scope ne lastCtx.scope) || (curOwner ne lastCtx.owner)) &&
-              !curOwner.isPackageObject
-              // Package objects are never searched directly. We wait until we
-              // hit the enclosing package. That way we make sure we consider
-              // all overloaded alternatives of a definition, even if they are
-              // in different source files.
+            else ((ctx.scope ne lastCtx.scope) || (curOwner ne lastCtx.owner))
+                // Was: ... && !curOwner.isPackageObject
+                //      Package objects are never searched directly. We wait until we
+                //      hit the enclosing package. That way we make sure we consider
+                //      all overloaded alternatives of a definition, even if they are
+                //      in different source files.
+                //
+                // But this is now disabled since otherwise we will not see self type refinements
+                // for opaque types.
+                // We should evaluate later whether we want to keep & spec it that way,
+                // or go back to the old scheme and compensate for opaque type refinements.
 
           if (isNewDefScope) {
             val defDenot = ctx.denotNamed(name, required)

tests/neg/toplevel-overload-1/defs_1.scala

@@ -0,0 +1,15 @@
+package top
+
+def hello(name: String) = s"hello, $name"
+def hello(x: Int) = x.toString
+
+object O {
+  def hi = hello("Bob")
+  def gb = hello(true)  // OK
+}
+
+val test1 = top.hello(false)   // OK, all overloaded variants are considered
+
+val test2 = hello(false)  // error , since we now consider only local overloaded definitions
+                          // in the same compilation unit.
+                          // See comment on line 280 in Typer#findRef.

tests/neg/toplevel-overload-1/moredefs_1.scala

@@ -0,0 +1,4 @@
+package top
+
+def hello(b: Boolean): String = if (b) "yes" else "no"
+

tests/run/toplevel-overloads/defs_1.scala

@@ -9,4 +9,4 @@ object O {
 }
 
 val test1 = top.hello(false)
-val test2 = hello(false)
+// val test2 = hello(false)   // does not work anymore, see comment on line 280 in Typer#findRef.