assertNull(v);
                  return null;
                }));
    expectUnchanged();
    assertEquals(getNumElements(), getMap().size());
  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  @CollectionSize.Require(absent = ZERO)
  public void testCompute_presentToPresent() {
    assertEquals(
        "Map.compute(present, functionReturningValue) should return new value",
        v3(),
        getMap()

                  assertNull(v);
                  return null;
                }));
    expectUnchanged();
    assertEquals(getNumElements(), getMap().size());
  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  @CollectionSize.Require(absent = ZERO)
  public void testCompute_presentToPresent() {
    assertEquals(
        "Map.compute(present, functionReturningValue) should return new value",
        v3(),
        getMap()

  }

  // retainAll(empty)

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testRetainAll_emptyPreviouslyEmpty() {
    expectReturnsFalse(empty);
    expectUnchanged();
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testRetainAll_emptyPreviouslyEmptyUnsupported() {

    assertNull(navigableSet.higher(e0()));
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testEmptySetPollLast() {
    assertNull(navigableSet.pollLast());
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ONE)
  public void testSingletonSetPollFirst() {
    assertEquals(a, navigableSet.pollFirst());

      }
    }
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testAsMapGetNullKeyPresent() {
    initMultimapWithNullKey();
    assertContentsAnyOrder(multimap().asMap().get(null), getValueForNullKey());
  }

  @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
  public void testAsMapGetNullKeyAbsent() {

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class MapIsEmptyTester<K, V> extends AbstractMapTester<K, V> {
  @CollectionSize.Require(ZERO)
  public void testIsEmpty_yes() {
    assertTrue("isEmpty() should return true", getMap().isEmpty());
  }

  @CollectionSize.Require(absent = ZERO)
  public void testIsEmpty_no() {
    assertFalse("isEmpty() should return false", getMap().isEmpty());
  }

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class CollectionIsEmptyTester<E> extends AbstractCollectionTester<E> {
  @CollectionSize.Require(ZERO)
  public void testIsEmpty_yes() {
    assertTrue("isEmpty() should return true", collection.isEmpty());
  }

  @CollectionSize.Require(absent = ZERO)
  public void testIsEmpty_no() {
    assertFalse("isEmpty() should return false", collection.isEmpty());
  }

  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_otherListContainingNull() {
    List<E> other = new ArrayList<>(getSampleElements());
    other.set(other.size() / 2, null);
    assertFalse(
        "Two Lists should not be equal if exactly one of them has null at a given index.",
        getList().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class ListRemoveAllTester<E> extends AbstractListTester<E> {
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testRemoveAll_duplicate() {
    ArrayWithDuplicate<E> arrayAndDuplicate = createArrayWithDuplicateElement();

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class ListRemoveAllTester<E> extends AbstractListTester<E> {
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testRemoveAll_duplicate() {
    ArrayWithDuplicate<E> arrayAndDuplicate = createArrayWithDuplicateElement();