@Test
public void takeIf_nullInput_returnsNullIfFalse() {

    final AtomicBoolean takeIfCalled = new AtomicBoolean(false);
    final SimpleClass returned = take((SimpleClass) null)
            .takeIf((in) -> {
                takeIfCalled.set(true);
                return false;
            })
            .unwrap();
    Assert.assertTrue(takeIfCalled.get());
    Assert.assertNull(returned);
}