anchor.diff:  
     _ServerNotifications(this.server);
   
  -  Stream<ServerStatusParams> get serverStatusEvents =>
  -      _serverStatusController.stream;
  -
     Stream<AnalysisErrorsParams> get analysisErrorsEvents =>
         _analysisErrorsController.stream;
  -
  -  Future listenToServer(Server server) async {
  -    server.listenToOutput(notificationProcessor: handleEvent);
  -
  -    await server.send(SERVER_REQUEST_SET_SUBSCRIPTIONS,
  -        ServerSetSubscriptionsParams([ServerService.STATUS]).toJson());
  -  }
  -
  -  @override
  -  void onServerStatus(ServerStatusParams event) {
  -    if (event.analysis != null) {
  -      _serverStatusController.add(event);
  -    }
  -  }
   
     Future get onNextAnalysisComplete {
       Completer completer = Completer();
  
positive.code:     return 0;
    }
  
    /// Parse and validate the user's options; throw a UsageException if there are
    /// issues, and return an [MigrateOptions] result otherwise.
    MigrateOptions _parseAndValidateOptions() {
  
negative.code:   @override
    final bool hidden;
  
    MigrateCommand({this.logProvider, this.hidden = false}) {
      MigrateOptions.defineOptions(argParser);
    }
  
    @override
    String get description =>
  