rangeSet.add(range1);
        rangeSet.add(range2);
        testIntersects(rangeSet);
        testIntersects(rangeSet.complement());
      }
    }
  }

  public void testEmptyEnclosing() {
    testEnclosing(TreeRangeSet.<Integer>create());
    testEnclosing(TreeRangeSet.<Integer>create().complement());
  }

  public void testAllSingleRangesEnclosing() {