Iterable<Long> iterable = iterable(Collections.<Long>emptySet());
    assertThat(ImmutableLongArray.copyOf(iterable)).isSameInstanceAs(ImmutableLongArray.of());
  }

  public void testCopyOf_iterable_notCollection_nonempty() {
    List<Long> list = Arrays.asList(0L, 1L, 3L);
    ImmutableLongArray iia = ImmutableLongArray.copyOf(iterable(list));
    list.set(2, 2L);