anchor.diff:      return socket1;
     }
   
  -  void add(T text) => controller.add(text);
  +  void add(dynamic text) => controller.add(text as T);
   
     void allowMultipleListeners() {
       stream = stream.asBroadcastStream();
  
positive.code:     pumpEventQueue().then((_) {
        responseController.addError(new NoResponseException(request));
      });
      return responseController.stream.firstWhere((response) {
        return response.id == id;
      });
    }
  }
  
  
negative.code:   Future close([int code, String reason]) =>
        controller.close().then((_) => twin.controller.close());
  
    StreamSubscription<T> listen(void onData(dynamic event),
            {Function onError, void onDone(), bool cancelOnError}) =>
        stream.listen((T data) => onData(data),
            onError: onError, onDone: onDone, cancelOnError: cancelOnError);
  
    noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
  
    Stream<T> where(bool test(dynamic t)) => stream.where((T data) => test(data));
  }
  
  class MockSource extends StringTypedMock implements Source {
  