public static void AdvanceBy(this TestScheduler @this, TimeSpan time)
 {
     @this.AssertNotNull(nameof(@this));
     @this.AdvanceBy(time.Ticks);
 }
 public static void ScheduleRelative(this TestScheduler @this, TimeSpan dueTime, Action action)
 {
     @this.AssertNotNull(nameof(@this));
     @this.ScheduleRelative(dueTime.Ticks, action);
 }
 public static void ScheduleRelative <TState>(this TestScheduler @this, TState state, TimeSpan dueTime, Func <IScheduler, TState, IDisposable> action)
 {
     @this.AssertNotNull(nameof(@this));
     @this.ScheduleRelative(state, dueTime.Ticks, action);
 }
 public static void AdvanceTo(this TestScheduler @this, DateTime dateTime)
 {
     @this.AssertNotNull(nameof(@this));
     @this.AdvanceTo(dateTime.Ticks);
 }