anchor.diff:      return null;
     }
   
  -  /**
  -   * Returns `true` if there is a subscription for the given [service] and
  -   * [file].
  -   */
  +  /// Returns `true` if there is a subscription for the given [service] and
  +  /// [file].
     bool _hasAnalysisServiceSubscription(AnalysisService service, String file) {
       return analysisServices[service]?.contains(file) ?? false;
     }
  
positive.code:         libraryName: libraryName);
    }
  
    /**
     * Run [f] in a new [Future].
     *
     * This method is used to delay sending notifications. If there is a more
     * important consumer of an analysis results, specifically a code completion
     * computer, we want it to run before spending time of sending notifications.
     *
     * TODO(scheglov) Consider replacing this with full priority based scheduler.
     *
     * TODO(scheglov) Alternatively, if code completion work in a way that does
     * not produce (at first) fully resolved unit, but only part of it - a single
     * method, or a top-level declaration, we would not have this problem - the
     * completion computer would be the only consumer of the partial analysis
     * result.
     */
    void _runDelayed(f()) {
      new Future(f);
    }
  }
  
  /**
   * Used to record server exceptions.
   */
  class ServerException {
    final String message;
    final dynamic exception;
  
negative.code: //    });
    }
  
    /// If the state location can be accessed, return the file byte store,
    /// otherwise return the memory byte store.
    ByteStore _createByteStore() {
      const int M = 1024 * 1024 /*1 MiB*/;
      const int G = 1024 * 1024 * 1024 /*1 GiB*/;
  