anchor.diff:    List<String> _undoList = new List<String>();
   
     int insertPos = -1;
  -
  -  final TextProcessingService _textProcessingService;
  -  final TextareaDomService _textareaDomService;
   
     ReplaceDialogComponent(this._textProcessingService,
         this._textareaDomService);
  
positive.code:     replacementText ??= "";
      if (textToReplace.length > 0) {
        TextareaSelection selInfo = _textareaDomService.getCurrentSelectionInfo();
        note.text = getUpdatedText();
        saveAndUpdateState(selInfo.start);
      }
    }
  
    void saveAndUpdateState(int cursorPos) {
      trackCursorPosition(cursorPos);
      note.save();
      _undoList.add(note.text);
    }
  
negative.code:     selector: 'replace-dialog',
      templateUrl: 'replace_component.html',
      providers: const [TextProcessingService, TextareaDomService])
  class ReplaceDialogComponent implements OnChanges {
  
    final TextProcessingService _textProcessingService;
    final TextareaDomService _textareaDomService;
  
    @Input()
    bool showDialog = false;
  