assertThat(longIterator.nextLong()).isEqualTo(2);
    assertThat(longIterator.nextLong()).isEqualTo(3);
    assertThat(longIterator.hasNext()).isFalse();
  }

  public void testCopyOf_array_empty() {
    /*
     * We don't guarantee the same-as property, so we aren't obligated to test it. However, it's
     * useful in testing - when two things are the same then one can't have bugs the other doesn't.
     */