expectAddFailure(sortedMultiset.tailMultiset(b.getElement(), OPEN), b);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), CLOSED), a);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), CLOSED), b);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), OPEN), a);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), OPEN), b);

    expectAddFailure(sortedMultiset.tailMultiset(b.getElement(), OPEN), b);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), CLOSED), a);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), CLOSED), b);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), OPEN), a);
    expectAddFailure(sortedMultiset.tailMultiset(c.getElement(), OPEN), b);

    features.addAll(parentBuilder.getFeatures());

    if (!features.remove(SERIALIZABLE_INCLUDING_VIEWS)) {
      features.remove(SERIALIZABLE);
    }

    SortedMultiset<E> emptyMultiset = (SortedMultiset<E>) delegate.create();
    Comparator<? super E> comparator = emptyMultiset.comparator();
    SampleElements<E> samples = delegate.samples();
    List<E> samplesList =

final class UnmodifiableSortedMultiset<E extends @Nullable Object> extends UnmodifiableMultiset<E>
    implements SortedMultiset<E> {
  UnmodifiableSortedMultiset(SortedMultiset<E> delegate) {
    super(delegate);
  }

  @Override
  protected SortedMultiset<E> delegate() {
    return (SortedMultiset<E>) super.delegate();
  }

  @Override
  public Comparator<? super E> comparator() {
    return delegate().comparator();

    TreeMultisetImpl {
      @Override
      public <E extends Comparable<E>> SortedMultiset<E> create(Collection<E> contents) {
        return TreeMultiset.create(contents);
      }
    },
    ImmutableSortedMultisetImpl {
      @Override
      public <E extends Comparable<E>> SortedMultiset<E> create(Collection<E> contents) {
        return ImmutableSortedMultiset.copyOf(contents);
      }
    };

    TreeMultisetImpl {
      @Override
      public <E extends Comparable<E>> SortedMultiset<E> create(Collection<E> contents) {
        return TreeMultiset.create(contents);
      }
    },
    ImmutableSortedMultisetImpl {
      @Override
      public <E extends Comparable<E>> SortedMultiset<E> create(Collection<E> contents) {
        return ImmutableSortedMultiset.copyOf(contents);
      }
    };

      }
    }

    // Test that toArray() is used to make a defensive copy in copyOf(), so concurrently modified
    // synchronized collections can be safely copied.
    SortedMultiset<String> toCopy = mock(SortedMultiset.class);
    TestHashSet<Entry<String>> entrySet = new TestHashSet<>();
    when((Comparator<Comparable<String>>) toCopy.comparator())
        .thenReturn(Ordering.<Comparable<String>>natural());