@Test
void spliteratorCharacteristics() {

    final int c = instance.spliterator().characteristics();
    assertHasFlag(c, Spliterator.DISTINCT);
    assertHasFlag(c, Spliterator.IMMUTABLE);
    assertHasFlag(c, Spliterator.ORDERED);
    assertHasFlag(c, Spliterator.SIZED);
    assertHasFlag(c, Spliterator.SUBSIZED);
    assertHasFlag(c, Spliterator.NONNULL);
}