private static void appendRoots(StringBuffer message, List<? extends PsiDirectory> source, Function<? super PsiDirectory, String> directoryPresentation) {
    int limit = Math.min(source.size(), 10);
    message.append(StringUtil.join(source.subList(0, limit), directoryPresentation, "\n"));
    if (limit < source.size()) {
      message.append("\n...\n");
    }
  }
private static void appendRoots(StringBuffer message, List<? extends PsiDirectory> source, Function<? super PsiDirectory, String> directoryPresentation)