assertThat(rangeSet.complement().asRanges())
          .containsExactlyElementsIn(complement.asRanges())
          .inOrder();
    }
  }

  public void testInvariantsEmpty() {
    testInvariants(TreeRangeSet.create());
  }

  public void testEmptyIntersecting() {
    testIntersects(TreeRangeSet.<Integer>create());
    testIntersects(TreeRangeSet.<Integer>create().complement());