Fix PostTyper normalization for named args

Needs to work also if named arg refers to an abstract type,
not a parameter.

1 files changed, 4 insertions, 6 deletions

diff --git a/src/dotty/tools/dotc/typer/Checking.scala b/src/dotty/tools/dotc/typer/Checking.scala
index 0baf48fa3..f18c5bf7c 100644
--- a/src/dotty/tools/dotc/typer/Checking.scala
+++ b/src/dotty/tools/dotc/typer/Checking.scala
@@ -54,13 +54,11 @@ object Checking {
     def traverse(tree: Tree)(implicit ctx: Context) = {
       tree match {
         case AppliedTypeTree(tycon, args) =>
-          // If `args` is a list of named argiments, return corresponding type parameters,
+          // If `args` is a list of named arguments, return corresponding type parameters,
           // otherwise return type parameters unchanged
-          def matchNamed(tparams: List[TypeSymbol], args: List[Tree]): List[TypeSymbol] = args match {
-            case Nil => Nil
-            case NamedArg(name, arg) :: args1 =>
-              val (matchingParam :: Nil, others) = tparams.partition(_.name == name)
-              matchingParam :: matchNamed(others, args1)
+          def matchNamed(tparams: List[TypeSymbol], args: List[Tree]): List[Symbol] = args match {
+            case (arg: NamedArg) :: _ =>
+              for (NamedArg(name, arg) <- args) yield tycon.tpe.member(name).symbol
             case _ =>
               tparams
           }