private static void swapAtComma(@NotNull PsiElement comma) {
    PsiElement prev = smartAdvance(comma, false);
    PsiElement next = smartAdvance(comma, true);
    if (prev != null && next != null) {
      if (Flipper.tryFlip(prev, next)) {
        return;
      }
      swapViaDocument(comma, prev, next);
    }
  }
private static void swapAtComma(@NotNull PsiElement comma)