assertEquals(Range.closed(3, 10), rangeSet.rangeContaining(5));
    assertTrue(rangeSet.contains(5));
    assertNull(rangeSet.rangeContaining(1));
    assertFalse(rangeSet.contains(1));
  }

  public void testRangeContaining2() {
    RangeSet<Integer> rangeSet = TreeRangeSet.create();
    rangeSet.add(Range.closed(3, 10));
    rangeSet.remove(Range.open(5, 7));
    assertEquals(Range.closed(3, 5), rangeSet.rangeContaining(5));