list.add("a");
    list.add("b");
    Iterator<String> iterator = list.iterator();
    advance(iterator, 1);
    assertEquals("b", iterator.next());
  }

  public void testAdvance_pastEnd() {
    List<String> list = new ArrayList<>();
    list.add("a");
    list.add("b");
    Iterator<String> iterator = list.iterator();
    advance(iterator, 5);
    assertFalse(iterator.hasNext());