@Test
void spliterator() {

    final List<Map.Entry<String, Integer>> expected = refStream().collect(Collectors.toList());
    final List<Map.Entry<String, Integer>> actual = new ArrayList<>();
    final Spliterator<Map.Entry<String, Integer>> spliterator = instance.spliterator();
    spliterator.forEachRemaining(actual::add);
    assertEquals(expected, actual);
}