}

  @Override
  public boolean equals(@CheckForNull Object obj) {
    if (obj == this) {
      return true;
    }
    if (obj instanceof FunctionalEquivalence) {
      FunctionalEquivalence<?, ?> that = (FunctionalEquivalence<?, ?>) obj;
      return function.equals(that.function) && resultEquivalence.equals(that.resultEquivalence);
    }
    return false;
  }

  @Override

  }

  @Override
  public boolean equals(@CheckForNull Object obj) {
    if (obj == this) {
      return true;
    }
    if (obj instanceof FunctionalEquivalence) {
      FunctionalEquivalence<?, ?> that = (FunctionalEquivalence<?, ?>) obj;
      return function.equals(that.function) && resultEquivalence.equals(that.resultEquivalence);
    }
    return false;
  }

  @Override

/** Basic sanity tests for classes in {@code common.base}. */

@GwtIncompatible
public class PackageSanityTests extends AbstractPackageSanityTests {
  public PackageSanityTests() {
    // package private classes like FunctionalEquivalence are tested through the public API.
    publicApiOnly();
  }

/** Basic sanity tests for classes in {@code common.base}. */

@GwtIncompatible
public class PackageSanityTests extends AbstractPackageSanityTests {
  public PackageSanityTests() {
    // package private classes like FunctionalEquivalence are tested through the public API.
    publicApiOnly();
  }

   *
   * @since 10.0
   */
  public final <F> Equivalence<F> onResultOf(Function<? super F, ? extends @Nullable T> function) {
    return new FunctionalEquivalence<>(function, this);
  }

  /**
   * Returns a wrapper of {@code reference} that implements {@link Wrapper#equals(Object)