testInvariants(rangeSet);
    assertThat(rangeSet.asRanges()).isEmpty();
    assertThat(rangeSet.complement().asRanges()).containsExactly(Range.<Integer>all());
  }

  public void testFillHoleExactly() {
    TreeRangeSet<Integer> rangeSet = TreeRangeSet.create();
    rangeSet.add(Range.closedOpen(1, 3));
    rangeSet.add(Range.closedOpen(4, 6));
    rangeSet.add(Range.closedOpen(3, 4));