Simplify the adaptation of types of return expressions

Add `adaptTypeOfReturn` hook to `AnnotationCheckers`.
Move adaptation of types of return expressions from `addAnnotations`
to `typedReturn` via `adaptTypeOfReturn` hook.

This resolves an inconsistency where previously types could have
a plus marker without additional CPS annotations. This also adds
additional test cases.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 79c1e660f0..8ba2d9e0fd 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -4096,7 +4096,8 @@ trait Typers extends Modes with Adaptations with Tags {
               if (typed(expr).tpe.typeSymbol != UnitClass)
                 unit.warning(tree.pos, "enclosing method " + name + " has result type Unit: return value discarded")
             }
-            treeCopy.Return(tree, checkDead(expr1)) setSymbol enclMethod.owner setType NothingClass.tpe
+            treeCopy.Return(tree, checkDead(expr1)).setSymbol(enclMethod.owner)
+                                                   .setType(adaptTypeOfReturn(expr1, restpt.tpe, NothingClass.tpe))
           }
         }
       }