public void GetRemainingWorkingTimeWithHolidayShouldOnlyEnumerateWorkingTime(DateTime startTime, TimeSpan workingHours, DateTime expectedDueDate, string expectation)
            {
                // Arrange
                var service = new ServicePlannerManager(Common.MockWorkDays(), Common.MockHolidayPeriods());

                // Act
                var result = service.GetRemainingWorkingTime(startTime, expectedDueDate);

                // Assert - 
                Assert.AreEqual(workingHours.TotalHours, result.TotalHours, expectation);
            }