public TextWithMnemonic append(@NotNull @Nls String textToAppend) {
    return new TextWithMnemonic(text + textToAppend,
                                mnemonicIndex < text.length() ? mnemonicIndex : mnemonicIndex + textToAppend.length(),
                                mnemonicSuffix);
  }
public TextWithMnemonic append(@NotNull @Nls String textToAppend)