for (long a : TEST_LONGS) {
      BigInteger big =
          (a >= 0) ? BigInteger.valueOf(a) : BigInteger.valueOf(a).add(BigInteger.ZERO.setBit(64));
      equalsTester.addEqualityGroup(
          UnsignedLong.fromLongBits(a),
          UnsignedLong.valueOf(big),
          UnsignedLong.valueOf(big.toString()),
          UnsignedLong.valueOf(big.toString(16), 16));
    }

public abstract class AbstractStandardUndirectedGraphTest extends AbstractGraphTest {

  @After
  public void validateUndirectedEdges() {
    for (Integer node : graph.nodes()) {
      new EqualsTester()
          .addEqualityGroup(
              graph.predecessors(node), graph.successors(node), graph.adjacentNodes(node))
          .testEquals();
    }
  }

  @Override
  @Test
  public void nodes_checkReturnedSetMutability() {

        Set<Integer> expected = newHashSet();
        for (Integer i : contents) {
          if (EVEN.apply(i)) {
            expected.add(i);
          }
        }
        new EqualsTester()
            .addEqualityGroup(expected, filter(createUnfiltered(contents), EVEN))
            .testEquals();
      }
    }
  }

  public abstract static class AbstractFilteredSortedSetTest<C extends SortedSet<Integer>>

                return factory.getName()
                    + "("
                    + Joiner.on(", ").useForNull("null").join(factoryArgs)
                    + ")";
              }
            });
    tester.addEqualityGroup(instance, createInstance(factory, equalArgs));
    for (int i = 0; i < params.size(); i++) {
      List<Object> newArgs = Lists.newArrayList(args);

    FreshValueGenerator generator = new FreshValueGenerator();
    EqualsTester tester = new EqualsTester();
    for (int i = 0; i < instances; i++) {
      tester.addEqualityGroup(generator.generateFresh(type));
    }
    tester.testEquals();
  }

  private static <T> void assertEqualInstance(Class<T> type, T value) {
    FreshValueGenerator generator = new FreshValueGenerator();

    multimap.put("foo", 1);
    multimap.put("bar", 2);
    Multimap<String, Integer> multimapView = Multimaps.forMap(map);
    new EqualsTester().addEqualityGroup(multimap, multimapView).addEqualityGroup(map).testEquals();
    Multimap<String, Integer> multimap2 = HashMultimap.create();
    multimap2.put("foo", 1);
    assertFalse(multimapView.equals(multimap2));
    multimap2.put("bar", 1);

    FreshValueGenerator generator = new FreshValueGenerator();
    EqualsTester tester = new EqualsTester();
    for (int i = 0; i < instances; i++) {
      tester.addEqualityGroup(generator.generateFresh(type));
    }
    tester.testEquals();
  }

  private static <T> void assertEqualInstance(Class<T> type, T value) {
    FreshValueGenerator generator = new FreshValueGenerator();

    multimap.put("a", 1);
    multimap.put("b", 2);
    multimap.put("a", 3);
    multimap.put("c", 4);
    LinkedHashMultimap<String, Integer> copy = LinkedHashMultimap.create(multimap);
    new EqualsTester().addEqualityGroup(multimap, copy).testEquals();
  }

  public void testCreateFromSizes() {
    LinkedHashMultimap<String, Integer> multimap = LinkedHashMultimap.create(20, 15);
    multimap.put("foo", 1);

        assertEquals(newHashSet(elements), multimap.asMap().entrySet());
      }
    }.test();
  }

  public void testEquals() {
    new EqualsTester()
        .addEqualityGroup(
            LinkedListMultimap.create(), LinkedListMultimap.create(), LinkedListMultimap.create(1))
        .testEquals();
  }

  @GwtIncompatible // reflection
  public void testNulls() throws Exception {

  private static void assertHashStringEquivalence(HashFunction hashFunction, Random random) {
    // Test that only data and data-order is important, not the individual operations.
    new EqualsTester()
        .addEqualityGroup(
            hashFunction.hashUnencodedChars("abc"),
            hashFunction.newHasher().putUnencodedChars("abc").hash(),
            hashFunction.newHasher().putUnencodedChars("ab").putUnencodedChars("c").hash(),