public void AddWorkingDays_Subtract1Day_PreviousDayIsWorkday()
        {
            var today = new DateTime(2018, 01, 03);

            var workingCalendar    = new WorkingCalendar(new Dictionary <DateTime, DayType>());
            var previousWorkingDay = workingCalendar.AddWorkingDays(today, -1);

            Assert.AreEqual(new DateTime(2018, 01, 02), previousWorkingDay);
        }
        public void AddWorkingDays_Add1Day_NextDayIsWorkday()
        {
            var today = new DateTime(2018, 01, 01);

            var workingCalendar = new WorkingCalendar(new Dictionary <DateTime, DayType>());
            var nextWorkingDay  = workingCalendar.AddWorkingDays(today, 1);

            Assert.AreEqual(new DateTime(2018, 01, 02), nextWorkingDay);
        }