@Test
public void testRemoveLast() {

    SafeIterableMap<Integer, Integer> map = from(1, 2, 3, 4).to(10, 20, 30, 40);
    assertThat(map.remove(4), is(40));
    assertThat(map, is(from(1, 2, 3).to(10, 20, 30)));
}