public void Success()
{
var ms = new SingleSubject <int>();
Assert.False(ms.HasObserver());
Assert.False(ms.HasCompleted());
Assert.False(ms.HasException());
Assert.IsNull(ms.GetException());
Assert.False(ms.HasValue());
Assert.False(ms.TryGetValue(out var _));
var to = ms.Test();
Assert.True(ms.HasObserver());
Assert.False(ms.HasCompleted());
Assert.False(ms.HasException());
Assert.IsNull(ms.GetException());
Assert.False(ms.HasValue());
Assert.False(ms.TryGetValue(out var _));
to.AssertSubscribed().AssertEmpty();
ms.OnSuccess(1);
Assert.False(ms.HasObserver());
Assert.True(ms.HasCompleted());
Assert.False(ms.HasException());
Assert.IsNull(ms.GetException());
Assert.True(ms.HasValue());
var v = default(int);
Assert.True(ms.TryGetValue(out v));
Assert.AreEqual(1, v);
to.AssertResult(1);
ms.Test().AssertSubscribed().AssertResult(1);
ms.Test(true).AssertSubscribed().AssertEmpty();
}
