@Nonnull
    public static <T> Traverser<T> traverseStream(@Nonnull Stream<T> stream) {
        return traverseSpliterator(stream.spliterator()).onFirstNull(stream::close);
    }
@Test
    public void when_traverseStream_then_seeAllItems() {
        validateTraversal(traverseStream(of(1, 2)));
    }