public void CallsCompareTo() { var firstCall = new PhoneCall() { From = "AAAA", To = "BBBB", Caller = null, Direction = CallDirection.Incoming, Duration = 120, StartTime = new DateTime(2000, 10, 5, 10, 21, 20, 300) }; var lastCall = new PhoneCall() { From = "AAAA", To = "CCCC", Caller = null, Direction = CallDirection.Incoming, Duration = 100, StartTime = new DateTime(2000, 10, 5, 10, 20, 19, 700) }; Assert.IsTrue(firstCall.CompareTo(lastCall) == 0); }