long r = 0;
    List<Facade<Integer>> list = new ArrayList<>(reps);
    for (int i = 0; i < reps; i++) {
      Facade<Integer> localFuture = impl.newFacade();
      list.add(localFuture);
      localFuture.setException(exception);
    }
    for (int i = 0; i < reps; i++) {
      Facade<Integer> facade = list.get(i);
      try {
        facade.get();
        r++;

    Collection<List<Integer>> permutationSet =
        Collections2.permutations(Collections.<Integer>emptyList());

    assertEquals(1, permutationSet.size());
    assertTrue(permutationSet.contains(Collections.<Integer>emptyList()));

    Iterator<List<Integer>> permutations = permutationSet.iterator();
    assertNextPermutation(Collections.<Integer>emptyList(), permutations);

  }

  private final boolean allowsSelfLoops;
  private final ElementOrder<Integer> incidentEdgeOrder;

  public StandardMutableUndirectedGraphTest(
      boolean allowsSelfLoops, ElementOrder<Integer> incidentEdgeOrder) {
    this.allowsSelfLoops = allowsSelfLoops;
    this.incidentEdgeOrder = incidentEdgeOrder;
  }

  @Override
  public MutableGraph<Integer> createGraph() {
    return GraphBuilder.undirected()

  }

  @Override
  TreeBasedTable<String, Integer, Character> makeTable() {
    TreeBasedTable<String, Integer, Character> table = TreeBasedTable.create();
    table.put("a", 1, 'a');
    table.put("z", 1, 'a');
    return table;
  }

  @Override
  protected Map<String, Map<Integer, Character>> makePopulatedMap() {
    TreeBasedTable<String, Integer, Character> table = makeTable();
    populateTable(table);

  public void testTransformEquals() {
    Map<String, Integer> underlying = ImmutableMap.of("a", 0, "b", 1, "c", 2);
    Map<String, Integer> expected = transformValues(underlying, Functions.<Integer>identity());

    assertMapsEqual(expected, expected);

    Map<String, Integer> equalToUnderlying = Maps.newTreeMap();
    equalToUnderlying.putAll(underlying);

    return new ConstantWeigher(constant);
  }

  /** Returns a {@link Weigher} that uses the integer key as the weight. */
  static Weigher<Integer, Object> intKeyWeigher() {
    return new IntKeyWeigher();
  }

  /** Returns a {@link Weigher} that uses the integer value as the weight. */
  static Weigher<Object, Integer> intValueWeigher() {
    return new IntValueWeigher();
  }

  public SubMapMultimapAsMapImplementsMapTest() {
    super(true, true, true);
  }

  private TreeMultimap<String, Integer> createMultimap() {
    TreeMultimap<String, Integer> multimap =
        TreeMultimap.create(
            Ordering.<String>natural().nullsFirst(), Ordering.<Integer>natural().nullsFirst());
    multimap.put("a", -1);
    multimap.put("a", -3);
    multimap.put("z", -2);
    return multimap;
  }

  @Override
  protected Table<String, Integer, Character> create(@Nullable Object... data) {
    Supplier<TreeMap<Integer, Character>> factory =
        new Supplier<TreeMap<Integer, Character>>() {
          @Override
          public TreeMap<Integer, Character> get() {
            return Maps.newTreeMap();
          }
        };
    Map<String, Map<Integer, Character>> backingMap = new LinkedHashMap<>();

    Cell<String, Integer, Character> entry = immutableCell("foo", 1, 'a');
    SerializableTester.reserializeAndAssert(entry);
  }

  public void testImmutableEntryToString() {
    Cell<String, Integer, Character> entry = immutableCell("foo", 1, 'a');
    assertThat(entry.toString()).isEqualTo("(foo,1)=a");

    Cell<@Nullable String, @Nullable Integer, @Nullable Character> nullEntry =

    testGraphMutation(GraphBuilder.undirected());
  }

  private static void testGraphMutation(GraphBuilder<? super Integer> graphBuilder) {
    Random gen = new Random(42); // Fixed seed so test results are deterministic.

    for (int trial = 0; trial < NUM_TRIALS; ++trial) {
      MutableGraph<Integer> graph = graphBuilder.allowsSelfLoops(true).build();

      assertThat(graph.nodes()).isEmpty();