@Test
void mapShortToDouble() {

    final ToShort<Short> toShort = s -> s;
    final ToDoubleMapper<Short, ToShort<Short>, ShortToDoubleFunction> toDoubleMapper =
            (ToDoubleMapper<Short, ToShort<Short>, ShortToDoubleFunction>)
                    MapperUtil.mapShortToDouble(toShort, s -> 1);
    assertEquals(MapperType.SHORT_TO_DOUBLE, toDoubleMapper.mapperType());
}