@Test
    void testMap() {
        final Optional<String> binLen = instance.map(String::length).map(Integer::toBinaryString).findFirst();
        assertEquals(Optional.of("1"), binLen);

        Optional<String> r = SingletonStream.of("C").map(s -> null).map(a -> "Olle").findAny();
        assertEquals(Optional.of("Olle"), r);

    }
Test of map method, of class SingletonStream.
common-parent/singletonstream/src/test/java/com/speedment/common/singletonstream/SingletonStreamTest.java