Itenso.TimePeriod.TimePeriodCollection.Move C# (CSharp) Method

        public virtual void Move( TimeSpan delta )
        {
            if ( delta == TimeSpan.Zero )
            {
                return;
            }

            foreach ( ITimePeriod timePeriod in periods )
            {
                DateTime start = timePeriod.Start + delta;
                timePeriod.Setup( start, start.Add( timePeriod.Duration ) );
            }
        }

        public void MoveTest()
        {
            DateTime now = ClockProxy.Clock.Now;
            SchoolDay schoolDay = new SchoolDay( now );
            TimePeriodCollection timePeriods = new TimePeriodCollection( schoolDay );

            DateTime startDate = schoolDay.Start;
            DateTime endDate = schoolDay.End;
            TimeSpan startDuration = timePeriods.Duration;

            TimeSpan duration = Duration.Hour;
            timePeriods.Move( duration );

            Assert.AreEqual( timePeriods.Start, startDate.Add( duration ) );
            Assert.AreEqual( timePeriods.End, endDate.Add( duration ) );
            Assert.AreEqual( timePeriods.Duration, startDuration );
        }