@Override
  public String toString() {
    StringBuilder result = new StringBuilder("UndoableGroup[");
    final boolean multiline = myActions.size() > 1;

    if (multiline) result.append("\n");

    result.append(StringUtil.join(myActions, each -> (multiline ? "  " : "") + each.toString(), ",\n"));

    if (multiline) result.append("\n");
    result.append("]");
    return result.toString();
  }
@Override
  public String toString()