assertFalse(filter(createUnfiltered(contents), EVEN).contains(new Object()));
      }
    }

    public void testAddAllFailsAtomically() {
      ImmutableList<Integer> toAdd = ImmutableList.of(2, 4, 3);
      for (List<Integer> contents : SAMPLE_INPUTS) {
        C filtered = filter(createUnfiltered(contents), EVEN);
        C filteredToModify = filter(createUnfiltered(contents), EVEN);