assertFalse(isNumber.apply(null));
  }

  @GwtIncompatible // Predicates.instanceOf
  public void testIsInstanceOf_interface() {
    Predicate<@Nullable Object> isComparable = Predicates.instanceOf(Comparable.class);

    assertTrue(isComparable.apply(1));
    assertTrue(isComparable.apply(2.0f));
    assertTrue(isComparable.apply(""));
    assertFalse(isComparable.apply(null));
  }

   *       Objects.equal}{@code (a, b)} implies that {@code predicate.apply(a) ==
   *       predicate.apply(b))}.
   * </ul>
   *
   * @throws NullPointerException if {@code input} is null and this predicate does not accept null
   *     arguments
   */
  boolean apply(@ParametricNullness T input);

  /**
   * Indicates whether another object is equal to this predicate.
   *

}

internal fun CacheControl.Builder.commonNoCache() =
  apply {
    this.noCache = true
  }

internal fun CacheControl.Builder.commonNoStore() =
  apply {
    this.noStore = true
  }

internal fun CacheControl.Builder.commonOnlyIfCached() =
  apply {
    this.onlyIfCached = true
  }

internal fun CacheControl.Builder.commonNoTransform() =
  apply {
    this.noTransform = true
  }

  ) = apply {
    actions += { stream ->
      stream.responseBody.writeUtf8(s)
      stream.responseBody.flush()
      responseSent.countDown()
    }
  }

  fun exhaustResponse() =
    apply {
      actions += { stream -> stream.responseBody.close() }
    }

  fun sleep(
    duration: Long,
    unit: TimeUnit,
  ) = apply {

    }

    fun allEnabledCipherSuites() =
      apply {
        require(tls) { "no cipher suites for cleartext connections" }
        this.cipherSuites = null
      }

    fun cipherSuites(vararg cipherSuites: CipherSuite): Builder =
      apply {
        require(tls) { "no cipher suites for cleartext connections" }

    checkNotNull(keyFunction);
    checkNotNull(valueFunction);
    return Collector.of(
        ImmutableMap.Builder<K, V>::new,
        (builder, input) -> builder.put(keyFunction.apply(input), valueFunction.apply(input)),
        ImmutableMap.Builder::combine,
        ImmutableMap.Builder::buildOrThrow);
  }

  static <T extends @Nullable Object, K, V> Collector<T, ?, ImmutableMap<K, V>> toImmutableMap(

    T instance = generator.newFreshProxy(interfaceType);
    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();
  }

          @Override
          public Arithmetic apply(Arithmetic arithmetic) {
            return new ForwardingArithmetic(arithmetic);
          }
        });
    tester.testForwarding(
        ParameterTypesDifferent.class,
        new Function<ParameterTypesDifferent, ParameterTypesDifferent>() {
          @Override
          public ParameterTypesDifferent apply(ParameterTypesDifferent delegate) {

        private
        fun newSimpleDateFormatUTC(pattern: String) = SimpleDateFormat(pattern).apply {
            timeZone = TimeZone.getTimeZone("UTC")
        }

        fun readBuildReceiptFromString(buildReceipt: String) =
            Properties().apply { load(buildReceipt.reader()) }

        const val buildReceiptFileName = "build-receipt.properties"

    socketFactory[ipv6] = server1.inetSocketAddress
    socketFactory[ipv4] = server2.inetSocketAddress

    client =
      client.newBuilder()
        .fastFallback(false)
        .apply {
          retryOnConnectionFailure = false
        }
        .build()

    executeSynchronously(request)
      .assertFailureMatches("stream was reset: REFUSED_STREAM")