1 files changed, 19 insertions, 0 deletions
diff --git a/src/compiler/scala/tools/nsc/symtab/Types.scala b/src/compiler/scala/tools/nsc/symtab/Types.scala
index 5ec350c35f..428bdb3ab6 100644
--- a/src/compiler/scala/tools/nsc/symtab/Types.scala
+++ b/src/compiler/scala/tools/nsc/symtab/Types.scala
@@ -122,6 +122,13 @@ trait Types requires SymbolTable {
     /** Is this type produced as a repair for an error? */
     def isError: boolean = symbol.isError;
 
+    /** Is this type produced as a repair for an error? */
+    def isErroneous: boolean = {
+      ErroneousTraverser.result = false;
+      ErroneousTraverser.traverse(this);
+      ErroneousTraverser.result
+    }
+
     /** Does this type denote a stable reference (i.e. singleton type)? */
     def isStable: boolean = false;
 
@@ -1340,6 +1347,18 @@ trait Types requires SymbolTable {
     }
   }
 
+  /** A map to implement the contains method */
+  object ErroneousTraverser extends TypeTraverser {
+    var result: boolean = _;
+    def traverse(tp: Type): TypeTraverser = {
+      if (!result) {
+        result = tp.isError
+        mapOver(tp)
+      }
+      this
+    }
+  }
+
   /** A map to compute the most deeply nested owner that contains all the symbols
    *  of thistype or prefixless typerefs/singletype occurrences in given type */
   object commonOwnerMap extends TypeMap {