'X', "d", 15, 'X', "d", 20, 'X', "d", 1, 'X', "e", 5, 'X');
    assertEquals("[1, 2, 3, 5, 10, 15, 20]", table.columnKeySet().toString());
  }

  public void testColumnKeySet_isSortedWithRealComparator() {
    table =
        create(
            String.CASE_INSENSITIVE_ORDER,
            Ordering.<Integer>natural().reverse(),
            "a",
            2,
            'X',