// overlap above
    assertEquals(Range.closed(6, 8), range.intersection(Range.closed(6, 10)));

    // adjacent above
    assertEquals(Range.openClosed(8, 8), range.intersection(Range.openClosed(8, 10)));

    // separate above
    expected =
        assertThrows(
            IllegalArgumentException.class, () -> range.intersection(Range.closed(10, 12)));

    assertEquals(
        Range.openClosed(0, 3),
        ContiguousSet.create(Range.closed(1, 3), integers()).range(OPEN, CLOSED));
    assertEquals(
        Range.openClosed(0, 3),
        ContiguousSet.create(Range.closedOpen(1, 4), integers()).range(OPEN, CLOSED));
    assertEquals(
        Range.openClosed(0, 3),

    // overlap above
    assertEquals(Range.closed(6, 8), range.intersection(Range.closed(6, 10)));

    // adjacent above
    assertEquals(Range.openClosed(8, 8), range.intersection(Range.openClosed(8, 10)));

    // separate above
    expected =
        assertThrows(
            IllegalArgumentException.class, () -> range.intersection(Range.closed(10, 12)));

    assertEquals(
        Range.openClosed(0, 3),
        ContiguousSet.create(Range.closed(1, 3), integers()).range(OPEN, CLOSED));
    assertEquals(
        Range.openClosed(0, 3),
        ContiguousSet.create(Range.closedOpen(1, 4), integers()).range(OPEN, CLOSED));
    assertEquals(
        Range.openClosed(0, 3),

          .add(Range.closed(2, 4))
          .add(Range.open(6, 7))
          .add(Range.closedOpen(8, 10))
          .add(Range.openClosed(15, 17))
          .build();

  private static final ImmutableRangeSet<Integer> RANGE_SET_TWO =
      ImmutableRangeSet.<Integer>builder()
          .add(Range.openClosed(0, 3))
          .add(Range.closed(5, 8))
          .add(Range.closedOpen(12, 15))
          .add(Range.open(19, 20))

    assertEquals(
        ImmutableMap.of(Range.closedOpen(5, 7), 1, Range.openClosed(9, 10), 2),
        sub.asMapOfRanges());
    assertEquals(
        ImmutableMap.of(Range.open(3, 7), 1, Range.openClosed(9, 10), 2, Range.closed(12, 16), 3),
        rangeMap.asMapOfRanges());

    sub.remove(Range.closed(3, 9));
    assertEquals(ImmutableMap.of(Range.openClosed(9, 10), 2), sub.asMapOfRanges());
    assertEquals(

      assertThrows(IllegalArgumentException.class, () -> builder.put(Range.closedOpen(ii, ii), 1));
      assertThrows(IllegalArgumentException.class, () -> builder.put(Range.openClosed(ii, ii), 1));
    }
  }

  public void testOverlapRejection() {
    for (Range<Integer> range1 : RANGES) {
      for (Range<Integer> range2 : RANGES) {
        boolean expectRejection =

    assertEquals(set, Sets.subSet(set, Range.openClosed(0, 12)));
    assertEquals(ImmutableSortedSet.of(2, 4), Sets.subSet(set, Range.openClosed(0, 4)));
    assertEquals(ImmutableSortedSet.of(4, 6), Sets.subSet(set, Range.openClosed(2, 6)));
    assertEquals(ImmutableSortedSet.of(4, 6), Sets.subSet(set, Range.openClosed(3, 7)));
    assertEquals(empty, Sets.subSet(set, Range.openClosed(20, 30)));

      if (set.isEmpty()) {
        /*
         * The (tooLow + 1, tooHigh) arguments below would be invalid because tooLow would be
         * greater than tooHigh.
         */
        return ContiguousSet.create(Range.openClosed(0, 1), DiscreteDomain.integers()).subSet(0, 1);
      }
      int tooHigh = set.last() + 1;
      int tooLow = set.first() - 1;
      set.add(tooHigh);
      set.add(tooLow);

      if (set.isEmpty()) {
        /*
         * The (tooLow + 1, tooHigh) arguments below would be invalid because tooLow would be
         * greater than tooHigh.
         */
        return ContiguousSet.create(Range.openClosed(0, 1), DiscreteDomain.integers()).subSet(0, 1);
      }
      int tooHigh = set.last() + 1;
      int tooLow = set.first() - 1;
      set.add(tooHigh);
      set.add(tooLow);