public void TimeElapsedInYearsSince_ValidGameDate_ReturnCorrectNumberOfDays() { //ARRANGE StandardDateTime time = new StandardDateTime(); time.SetDatetime(new System.DateTime(5196, 9, 1)); //ACT long days = time.TimeElapsedInYearsSince(new StandardDateTime(new System.DateTime(5203, 11, 1, 1, 2, 0))); //ASSERT Assert.AreEqual(7, days); }