return delegate;
          }
        };
    new EqualsTester().addEqualityGroup(forward).testEquals();
  }

  public void testEqualsSymmetric() {
    final Set<String> delegate = Sets.newHashSet("foo");
    ForwardingObject forward =
        new ForwardingObject() {
          @Override
          protected Object delegate() {
            return delegate;
          }
        };

  @CheckForNull private ThreadFactory backingThreadFactory = null;

  /** Creates a new {@link ThreadFactory} builder. */
  public ThreadFactoryBuilder() {}

  /**
   * Sets the naming format to use when naming threads ({@link Thread#setName}) which are created
   * with this ThreadFactory.
   *
   * @param nameFormat a {@link String#format(String, Object...)}-compatible format String, to which

    }

    @Override
    Set<E> createElementSet() {
      return Sets.filter(unfiltered.elementSet(), predicate);
    }

    @Override
    Iterator<E> elementIterator() {
      throw new AssertionError("should never be called");
    }

    @Override
    Set<Entry<E>> createEntrySet() {
      return Sets.filter(
          unfiltered.entrySet(),
          new Predicate<Entry<E>>() {

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.collect.ObjectArrays;
import com.google.common.collect.Sets;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

    assertFalse(
        "Two Sets should not be equal if exactly one of them contains null.",
        getSet().equals(other));
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  public void testEquals_smallerSet() {
    Collection<E> fewerElements = getSampleElements(getNumElements() - 1);
    assertFalse(
        "Sets of different sizes should not be equal.",

import com.google.common.collect.testing.SampleElements.Enums;
import java.util.Collections;
import java.util.List;
import java.util.Set;

/**
 * An abstract TestSetGenerator for generating sets containing enum values.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestEnumSetGenerator implements TestSetGenerator<AnEnum> {
  @Override

    assertEquals("[" + JOINER.join(map.values()) + "]", map.values().toString());

    assertEquals(MinimalSet.from(map.entrySet()), map.entrySet());
    assertEquals(Sets.newHashSet(map.keySet()), map.keySet());
  }

  @Override
  Set<Integer> createUnfiltered(Iterable<Integer> contents) {
    return Sets.newHashSet(contents);
  }

  @Override
  Set<Integer> filter(Set<Integer> elements, Predicate<? super Integer> predicate) {
    return Sets.filter(elements, predicate);
  }

  @Override
  public void setUp() {
    friends = Sets.newHashSet("Tom", "Joe", "Dave");
    enemies = Sets.newHashSet("Dick", "Harry", "Tom");
  }

  public void testUnion() {
    Set<String> all = Sets.union(friends, enemies);
    assertEquals(5, all.size());

    ImmutableSet<String> immut = Sets.union(friends, enemies).immutableCopy();
    HashSet<String> mut = Sets.union(friends, enemies).copyInto(new HashSet<String>());

    return delegate.toArray(other);
  }

  @Override
  public String toString() {
    return delegate.toString();
  }

  // TODO(cpovirk): equals(), as well, in case it's any faster than Sets.equalsImpl?

  @Override
  public int hashCode() {
    return delegate.hashCode();
  }