Merge pull request #2996 from paulp/pr/3971

SI-3971 error message carat mispoints at curried methods.

2 files changed, 14 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
index 1f4d5cbac2..f893e4f0ff 100644
--- a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
@@ -157,6 +157,16 @@ trait ContextErrors {
       }
 
       def AdaptTypeError(tree: Tree, found: Type, req: Type) = {
+        // SI-3971 unwrapping to the outermost Apply helps prevent confusion with the
+        // error message point.
+        def callee = {
+          def unwrap(t: Tree): Tree = t match {
+            case Apply(app: Apply, _) => unwrap(app)
+            case _                    => t
+          }
+          unwrap(tree)
+        }
+
         // If the expected type is a refinement type, and the found type is a refinement or an anon
         // class, we can greatly improve the error message by retyping the tree to recover the actual
         // members present, then display along with the expected members. This is done here because
@@ -181,7 +191,7 @@ trait ContextErrors {
         }
         assert(!foundType.isErroneous && !req.isErroneous, (foundType, req))
 
-        issueNormalTypeError(tree, withAddendum(tree.pos)(typeErrorMsg(foundType, req)))
+        issueNormalTypeError(callee, withAddendum(callee.pos)(typeErrorMsg(foundType, req)))
         infer.explainTypes(foundType, req)
       }
 
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 157c6ba4de..d88a615c7f 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -4177,6 +4177,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper
             case If(_, t, e)                        => treesInResult(t) ++ treesInResult(e)
             case Try(b, catches, _)                 => treesInResult(b) ++ catches
             case Typed(r, Function(Nil, EmptyTree)) => treesInResult(r)
+            case Select(qual, name)                 => treesInResult(qual)
+            case Apply(fun, args)                   => treesInResult(fun) ++ args.flatMap(treesInResult)
+            case TypeApply(fun, args)               => treesInResult(fun) ++ args.flatMap(treesInResult)
             case _                                  => Nil
           })
           def errorInResult(tree: Tree) = treesInResult(tree) exists (_.pos == typeError.errPos)