Fix #1990: Handle case where inlining changes class of outer

The new situation in the test was that outer of the inlined method
was `A` but it's as seen from type is a subtype `B`.

We need two fixes:

 - Ignore outerSelects in TreeChecker. These are treated as having fixed symbols.
 - Adapt the outer-path logic to deal with code that's moved to another context.

1 files changed, 5 insertions, 1 deletions

diff --git a/compiler/src/dotty/tools/dotc/transform/TreeChecker.scala b/compiler/src/dotty/tools/dotc/transform/TreeChecker.scala
index b2b99160b..7a4af647f 100644
--- a/compiler/src/dotty/tools/dotc/transform/TreeChecker.scala
+++ b/compiler/src/dotty/tools/dotc/transform/TreeChecker.scala
@@ -12,6 +12,7 @@ import core.Types._
 import core.Flags._
 import core.Constants._
 import core.StdNames._
+import core.NameOps._
 import core.Decorators._
 import core.TypeErasure.isErasedType
 import core.Phases.Phase
@@ -336,7 +337,10 @@ class TreeChecker extends Phase with SymTransformer {
       assert(tree.isTerm || !ctx.isAfterTyper, tree.show + " at " + ctx.phase)
       val tpe = tree.typeOpt
       val sym = tree.symbol
-      if (!tpe.isInstanceOf[WithFixedSym] && sym.exists && !sym.is(Private)) {
+      if (!tpe.isInstanceOf[WithFixedSym] &&
+          sym.exists && !sym.is(Private) &&
+          !tree.name.isOuterSelect // outer selects have effectively fixed symbols
+          ) {
         val qualTpe = tree.qualifier.typeOpt
         val member =
           if (sym.is(Private)) qualTpe.member(tree.name)