public void GetElapsedTime(int day, int elapsedTime, bool isAfterCurrent) { Mock <IDatos> idatos = new Mock <IDatos>(); DateTimeService dateTimeService = new DateTimeService(); idatos.Setup(m => m.Date).Returns(new DateTime(2020, 1, day)); dateTimeService.CurrentDateTime = () => new DateTime(2020, 1, 20); var result = dateTimeService.GetElapsedTime(idatos.Object, isAfterCurrent); TimeSpan timeSpan = new TimeSpan(elapsedTime, 0, 0, 0); Assert.AreEqual(timeSpan, result); }