SI-4842 Forbid access to in-construction this in self-constructor args

The check was already in place for direct calls to the super constructor.
Without this additional check, ExplicitOuter crashes, as it doesn't create
an $outer pointer for the constructor-arg scoped inner object, but expects
one to exist when transforming the Outer.this reference.

1 files changed, 7 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
index bcf2ba6b71..fcb73f5947 100644
--- a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
@@ -222,7 +222,13 @@ trait ContextErrors {
         NormalTypeError(tree, "super constructor cannot be passed a self reference unless parameter is declared by-name")
 
       def SuperConstrArgsThisReferenceError(tree: Tree) =
-        NormalTypeError(tree, "super constructor arguments cannot reference unconstructed `this`")
+        ConstrArgsThisReferenceError("super", tree)
+
+      def SelfConstrArgsThisReferenceError(tree: Tree) =
+        ConstrArgsThisReferenceError("self", tree)
+
+      private def ConstrArgsThisReferenceError(prefix: String, tree: Tree) =
+        NormalTypeError(tree, s"$prefix constructor arguments cannot reference unconstructed `this`")
 
       def TooManyArgumentListsForConstructor(tree: Tree) = {
         issueNormalTypeError(tree, "too many argument lists for constructor invocation")