private static int getCommentStart(Editor editor, PsiFile psiFile, int line) {
    int offset = editor.getDocument().getLineStartOffset(line);
    CharSequence chars = editor.getDocument().getCharsSequence();
    offset = CharArrayUtil.shiftForward(chars, offset, " \t");
    final Commenter commenter = findCommenter(editor, psiFile, line);
    if (commenter == null) return -1;
    String prefix = commenter.getLineCommentPrefix();
    if (prefix == null) prefix = commenter.getBlockCommentPrefix();
    if (prefix == null) return -1;
    return CharArrayUtil.regionMatches(chars, offset, prefix) ? offset : -1;
  }
private static int getCommentStart(Editor editor, PsiFile psiFile, int line)