Index: pkg/compiler/lib/src/js_backend/namer_names.dart |
diff --git a/pkg/compiler/lib/src/js_backend/namer_names.dart b/pkg/compiler/lib/src/js_backend/namer_names.dart |
index 5d6eae3b59b22397624a5f598eee5357de9d6654..60e159745cea7327c9ea61b72e01a83cf0ccd05c 100644 |
--- a/pkg/compiler/lib/src/js_backend/namer_names.dart |
+++ b/pkg/compiler/lib/src/js_backend/namer_names.dart |
@@ -193,7 +193,8 @@ class TokenName extends _NamerName implements jsAst.ReferenceCountedAstNode { |
int get hashCode => super.hashCode; |
finalize() { |
- assert(!isFinalized); |
+ assert(invariant(NO_LOCATION_SPANNABLE, !isFinalized, |
+ message: "TokenName($key)=$_name has already been finalized.")); |
_name = _scope.getNextName(); |
} |
} |