} catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddAll_supportedNonePresent() {
    assertTrue(
        "addAll(nonePresent) should return true", collection.addAll(createDisjointCollection()));
    expectAdded(e3(), e4());
  }

  @CollectionFeature.Require(absent = SUPPORTS_ADD)