protected void verify(List<String> elements) {
        assertEquals(elements, new ArrayList<>(multimap.keys()));
      }
    }.test();
  }

  @GwtIncompatible // unreasonably slow
  public void testValuesIteration() {
    List<Integer> addItems = ImmutableList.of(99, 88, 77);

    for (int startIndex : new int[] {0, 3, 5}) {
      new ListIteratorTester<Integer>(
          3,
          addItems,