assertSame(value, callable.call());
    // Expect the same value on subsequent calls
    assertSame(value, callable.call());
  }

  @J2ktIncompatible
  @GwtIncompatible
  public void testAsAsyncCallable() throws Exception {
    final String expected = "MyCallableString";
    Callable<String> callable =
        new Callable<String>() {
          @Override
          public String call() throws Exception {