@Test
    void spliteratorTryAdvance() {
        final Spliterator<String> spliterator = instance.spliterator();
        final AtomicInteger cnt = new AtomicInteger();
        assertTrue(spliterator.tryAdvance(e -> cnt.incrementAndGet()));
        assertFalse(spliterator.tryAdvance(e -> cnt.incrementAndGet()));
    }
Test of mapToInt method, of class SingletonStream.
common-parent/singletonstream/src/test/java/com/speedment/common/singletonstream/SingletonStreamTest.java