public void TestFailDoesNotAllowThen()
        {
            promise
            .Then(NoArgCallback)
            .Fail(FailCallback)
            .Progress(ProgressCallback);


            promise.ReportFail(new Exception(exceptionStr));
            promise.Then(NoArgCallbackTwo);

            Assert.AreEqual(0, promise.ListenerCount());
        }
        public void TestCannotAddListenerTwiceFour()
        {
            promiseFourArg
            .Then(FourArgCallback)
            .Then(FourArgCallback);

            Assert.AreEqual(1, promiseFourArg.ListenerCount());
        }