assertThat(set.tailSet(strings[i], true))
          .containsExactlyElementsIn(sortedNumberNames(i, strings.length))
          .inOrder();
    }
  }

  public void testTailSetExclusive() {
    String[] strings = NUMBER_NAMES.toArray(new String[0]);
    ImmutableSortedSet<String> set = ImmutableSortedSet.copyOf(strings);
    sort(strings);
    for (int i = 0; i < strings.length; i++) {