public void Normal()
        {
            var dp1 = new DirectProcessor <int>();
            var dp2 = new DirectProcessor <int>();

            var ts = dp1.Window(dp2).Merge().Test();

            ts.AssertEmpty();

            dp1.OnNext(1);
            dp1.OnNext(2);

            dp2.OnNext(100);

            ts.AssertValues(1, 2)
            .AssertNoError()
            .AssertNotComplete();

            dp2.OnNext(200);

            ts.AssertValues(1, 2)
            .AssertNoError()
            .AssertNotComplete();

            dp1.OnNext(3);
            dp1.OnNext(4);
            dp1.OnNext(5);

            dp1.OnComplete();

            Assert.IsFalse(dp2.HasSubscribers);

            ts.AssertResult(1, 2, 3, 4, 5);
        }