private void highlightRegExpGroup(RegExpGroup group, HighlightManager highlightManager) {
    Editor editor = myRegExp.getEditor();
    if (editor == null) {
      return;
    }
    final PsiElement[] array = {group};
    List<RangeHighlighter> highlighter = new SmartList<>();
    highlightManager.addOccurrenceHighlights(editor, array, RegExpHighlighter.MATCHED_GROUPS, true, highlighter);
    myRegExpHighlight = highlighter.get(0);
  }
private void highlightRegExpGroup(RegExpGroup group, HighlightManager highlightManager)