actsLikeIteratorHelper(Lists.newArrayList("A", "B", "C"));
  }

  @GwtIncompatible // works but takes 5 minutes to run
  public void testPeekingIteratorAcceptsNullElements() {
    actsLikeIteratorHelper(Lists.<@Nullable String>newArrayList(null, "A", null));
  }

  public void testPeekOnEmptyList() {
    List<?> list = emptyList();