list.set(0, 2L);
    assertThat(array).isEqualTo(new long[] {2L, 1L});
    array[1] = 3L;
    assertThat(list).containsExactly(2L, 3L).inOrder();
  }

  public void testAsList_toArray_roundTrip() {
    long[] array = {0L, 1L, 2L};
    List<Long> list = Longs.asList(array);
    long[] newArray = Longs.toArray(list);

    // Make sure it returned a copy
    list.set(0, 4L);