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 =
            range1.isConnected(range2) && !range1.intersection(range2).isEmpty();