protected Iterator<Integer> newTargetIterator() {
            return ImmutableList.of(1, 2).iterator();
          }
        };
    assertFailure(tester);
  }

  public void testUnknownOrder() {
    new IteratorTester<Integer>(
        3, MODIFIABLE, newArrayList(1, 2), IteratorTester.KnownOrder.UNKNOWN_ORDER) {
      @Override
      protected Iterator<Integer> newTargetIterator() {

        private @Nullable LinkedListMultimap<String, Integer> multimap;

        @Override
        protected ListIterator<Entry<String, Integer>> newTargetIterator() {
          multimap = create();
          multimap.putAll("foo", asList(2, 3));
          multimap.putAll("bar", asList(4, 5));
          multimap.put("foo", 6);

    new IteratorTester<String>(
        5, UNMODIFIABLE, asList("foo", "bar", "baz"), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<String> newTargetIterator() {
        return Lists.asList("foo", new String[] {"bar", "baz"}).iterator();
      }
    }.test();
  }

  private void checkFooBarBazList(List<String> list) {

   * in the given order. Warning: it is not enough to simply pull multiple iterators from the same
   * source Iterable, unless that Iterator is unmodifiable.
   */
  protected abstract I newTargetIterator();

  /**
   * Override this to verify anything after running a list of Stimuli.
   *
   * <p>For example, verify that calls to remove() actually removed the correct elements.
   *

   * in the given order. Warning: it is not enough to simply pull multiple iterators from the same
   * source Iterable, unless that Iterator is unmodifiable.
   */
  protected abstract I newTargetIterator();

  /**
   * Override this to verify anything after running a list of Stimuli.
   *
   * <p>For example, verify that calls to remove() actually removed the correct elements.
   *

      protected Iterator<String> newTargetIterator() {
        return of("a").iterator();
      }
    }.test();
  }

  @GwtIncompatible // slow (~30s)
  public void testIterator_general() {
    new IteratorTester<String>(
        5, UNMODIFIABLE, asList("a", "b", "c"), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<String> newTargetIterator() {

  public void testSkip_iterator() {
    new IteratorTester<Integer>(
        5, MODIFIABLE, newArrayList(2, 3), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return skip(new LinkedHashSet<>(asList(1, 2, 3)), 1).iterator();
      }
    }.test();
  }

  @GwtIncompatible // slow (~35s)
  public void testSkip_iteratorList() {

  public void testSkip_iterator() {
    new IteratorTester<Integer>(
        5, MODIFIABLE, newArrayList(2, 3), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return skip(new LinkedHashSet<>(asList(1, 2, 3)), 1).iterator();
      }
    }.test();
  }

  @GwtIncompatible // slow (~35s)
  public void testSkip_iteratorList() {

    Set<Set<Integer>> powerSet = powerSet(elements);
    new IteratorTester<Set<Integer>>(6, UNMODIFIABLE, expected, KNOWN_ORDER) {
      @Override
      protected Iterator<Set<Integer>> newTargetIterator() {
        return powerSet.iterator();
      }
    }.test();
  }

  public void testPowerSetIteration_iteratorTester_fast() {
    ImmutableSet<Integer> elements = ImmutableSet.of(1, 2);

            new LinkedList<>(values),
            IteratorTester.KnownOrder.UNKNOWN_ORDER) {
          private @Nullable MinMaxPriorityQueue<T> mmHeap;

          @Override
          protected Iterator<T> newTargetIterator() {
            mmHeap = MinMaxPriorityQueue.create(values);
            return mmHeap.iterator();
          }

          @Override
          protected void verify(List<T> elements) {