new EqualsTester()
        .addEqualityGroup(wrapperFunction.apply(instance), wrapperFunction.apply(instance))
        .addEqualityGroup(wrapperFunction.apply(generator.newFreshProxy(interfaceType)))
        // TODO: add an overload to EqualsTester to print custom error message?
        .testEquals();
  }

  private static <T> void testToString(
      Class<T> interfaceType, Function<? super T, ? extends T> wrapperFunction) {

 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingCollection<E extends @Nullable Object> extends ForwardingObject
    implements Collection<E> {
  // TODO(lowasser): identify places where thread safety is actually lost

  /** Constructor for use by subclasses. */
  protected ForwardingCollection() {}

  @Override
  protected abstract Collection<E> delegate();

   * this class ({@code Resources}) will be used instead.
   *
   * @throws IllegalArgumentException if the resource is not found
   */
  @CanIgnoreReturnValue // being used to check if a resource exists
  // TODO(cgdecker): maybe add a better way to check if a resource exists
  // e.g. Optional<URL> tryGetResource or boolean resourceExists
  public static URL getResource(String resourceName) {
    ClassLoader loader =

 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingCollection<E extends @Nullable Object> extends ForwardingObject
    implements Collection<E> {
  // TODO(lowasser): identify places where thread safety is actually lost

  /** Constructor for use by subclasses. */
  protected ForwardingCollection() {}

  @Override
  protected abstract Collection<E> delegate();

 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingList<E extends @Nullable Object> extends ForwardingCollection<E>
    implements List<E> {
  // TODO(lowasser): identify places where thread safety is actually lost

  /** Constructor for use by subclasses. */
  protected ForwardingList() {}

  @Override
  protected abstract List<E> delegate();

  @Override

        CollectionSize.ANY);
    return MapTestSuiteBuilder.using(generator)
        .named(name)
        .withFeatures(featuresList)
        .createTestSuite();
  }

  // TODO: consider being null-hostile in these tests

  private static Test testsForHashMapNullKeysForbidden() {
    return wrappedHashMapTests(
        new WrappedHashMapGenerator() {
          @Override

        .addEqualityGroup(orderedMirror)
        .addEqualityGroup(unordered, unorderedMirror)
        .testEquals();
  }

  // Tests for Graph.edges() and Network.asGraph().edges() methods
  // TODO(user): Move these to a more appropriate location in the test suite.

  @Test
  public void endpointPair_directedGraph() {
    MutableGraph<Integer> directedGraph = GraphBuilder.directed().allowsSelfLoops(true).build();

@GwtIncompatible // not worth using in GWT for now
final class CompactLinkedHashMap<K extends @Nullable Object, V extends @Nullable Object>
    extends CompactHashMap<K, V> {
  // TODO(lowasser): implement removeEldestEntry so this can be used as a drop-in replacement

  /** Creates an empty {@code CompactLinkedHashMap} instance. */
  public static <K extends @Nullable Object, V extends @Nullable Object>

      return new WrappedCallable<T>(callable);
    }

    @Override
    protected Runnable wrapTask(Runnable command) {
      return new WrappedRunnable(command);
    }
  }

  // TODO: If this test can ever depend on Mockito or the like, use it instead.
  private static final class MockExecutor implements ExecutorService {
    private String lastMethodCalled = "";
    private long lastTimeoutInMillis = -1;

        .addEqualityGroup(orderedMirror)
        .addEqualityGroup(unordered, unorderedMirror)
        .testEquals();
  }

  // Tests for Graph.edges() and Network.asGraph().edges() methods
  // TODO(user): Move these to a more appropriate location in the test suite.

  @Test
  public void endpointPair_directedGraph() {
    MutableGraph<Integer> directedGraph = GraphBuilder.directed().allowsSelfLoops(true).build();