initThreeCopies();
    assertEquals(3, getMultiset().count(e0()));
    Multiset.Entry<E> entry = getOnlyElement(getMultiset().entrySet());
    assertEquals(3, entry.getCount());
    assertTrue(getMultiset().remove(e0()));
    assertEquals(2, entry.getCount());
    assertTrue(getMultiset().elementSet().remove(e0()));
    assertEquals(0, entry.getCount());
    getMultiset().add(e0(), 2);
    assertEquals(2, entry.getCount());
  }

  public void testLastIndexOf_duplicate() {
    E[] array = createSamplesArray();
    array[getNumElements() / 2] = e0();
    collection = getSubjectGenerator().create(array);
    assertEquals(
        "lastIndexOf(duplicate) should return index of last occurrence",
        getNumElements() / 2,
        getList().lastIndexOf(e0()));
  }

        collection.removeAll(MinimalCollection.of(e0())));
    expectMissing(e0());
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testRemoveAll_somePresent() {
    assertTrue(
        "removeAll(intersectingCollection) should return true",
        collection.removeAll(MinimalCollection.of(e0(), e3())));
    expectMissing(e0());
  }

  public void testAddAllAtIndex_withDuplicates() {
    MinimalCollection<E> elementsToAdd = MinimalCollection.of(e0(), e1(), e0(), e1());
    assertTrue("addAll(n, hasDuplicates) should return true", getList().addAll(0, elementsToAdd));
    expectAdded(0, e0(), e1(), e0(), e1());
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)

  public void testAddAll_withDuplicates() {
    MinimalCollection<E> elementsToAdd = MinimalCollection.of(e0(), e1(), e0(), e1());
    assertTrue("addAll(hasDuplicates) should return true", getList().addAll(elementsToAdd));
    expectAdded(e0(), e1(), e0(), e1());
  }

    new IteratorTester<E>(
        4,
        MODIFIABLE,
        getSubjectGenerator().order(asList(e0(), e1(), e1(), e2())),
        IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<E> newTargetIterator() {
        return getSubjectGenerator().create(e0(), e1(), e1(), e2()).iterator();
      }
    }.test();
  }

  @CollectionSize.Require(SEVERAL)
  public void testRetainAll_countIgnored() {
    resetContainer(getSubjectGenerator().create(e0(), e2(), e1(), e0()));
    assertTrue(getList().retainAll(asList(e0(), e1())));
    assertContentsInOrder(getList(), e0(), e1(), e0());
  }

        "multiset.elementSet().contains(present) returned false",
        getMultiset().elementSet().contains(e0()));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testEntrySet_contains() {
    assertTrue(
        "multiset.entrySet() didn't contain [present, 1]",
        getMultiset().entrySet().contains(Multisets.immutableEntry(e0(), 1)));
  }

  public void testEntrySet_contains_count0() {
    assertFalse(

        "multiset.elementSet().contains(present) returned false",
        getMultiset().elementSet().contains(e0()));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testEntrySet_contains() {
    assertTrue(
        "multiset.entrySet() didn't contain [present, 1]",
        getMultiset().entrySet().contains(Multisets.immutableEntry(e0(), 1)));
  }

  public void testEntrySet_contains_count0() {
    assertFalse(

  private void assertZeroToZero() {
    assertSetCount(e3(), 0);
  }

  private void assertOneToOne() {
    assertSetCount(e0(), 1);
  }

  private void assertThreeToThree() {
    initThreeCopies();
    assertSetCount(e0(), 3);
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testSetCount_zeroToZero_addSupported() {
    assertZeroToZero();
  }