anchor.diff:      }
     }
   
  -  /// Return the annotations associated with the directive at the given
  -  /// [offset], or an empty list if the directive has no annotations or if
  -  /// there is no directive at the given offset.
  -  List<ElementAnnotation> getAnnotations(int offset) {
  -    if (annotationMap == null) {
  -      return const <ElementAnnotation>[];
  -    }
  -    return annotationMap[offset] ?? const <ElementAnnotation>[];
  -  }
  -
     @override
     ElementImpl getChild(String identifier) {
       //
  
positive.code:       TopLevelVariableElement from, TopLevelVariableElement to) {
      int index = _variables.indexOf(from);
      _variables[index] = to;
    }
  
    /// Set the annotations associated with the directive at the given [offset] to
    /// the given list of [annotations].
    void setAnnotations(int offset, List<ElementAnnotation> annotations) {
      annotationMap ??= new HashMap<int, List<ElementAnnotation>>();
      annotationMap[offset] = annotations;
    }
  
    @override
  
negative.code:   /// computed.
    Source librarySource;
  
    /// A list containing all of the top-level accessors (getters and setters)
    /// contained in this compilation unit.
    List<PropertyAccessorElement> _accessors;
  