for (Integer j : IN_ORDER_VALUES) {
        assertEquals(Objects.equals(i, j), range.contains(j));
      }
    }
  }

  public void testSingletonRange() {
    GeneralRange<@Nullable Integer> range = GeneralRange.range(ORDERING, 3, CLOSED, 3, CLOSED);
    for (Integer i : IN_ORDER_VALUES) {
      assertEquals(ORDERING.compare(i, 3) == 0, range.contains(i));
    }
  }