Testing an event-sourced object's behavior

EventSourcedBehaviorTest.cs

private AppointmentCreated CreateAppointmentCreatedEvent()
{
    return new AppointmentCreated(
        appointmentId: Guid.NewGuid(),
        startTime: DateTimeOffset.Now.AddHours(3),
        endTime: DateTimeOffset.Now.AddHours(4),
        title: "Appointment");
}

private AppointmentRenamed CreateAppointmentRenamedEvent()
{
    return new AppointmentRenamed(title: "Renamed appointment");
}

private Appointment CreateSut(IEnumerable<IEvent> events)
{
    var sut = new Appointment();
    
    foreach (var @event in events)
        sut.ReplayEvent(@event);
    
    return sut;
}

[Fact]
public void Reschedule_AppendsAppointmentRescheduled()
{
    // GIVEN these events have happened
    var events = new IEvent[]
                 {
                     CreateAppointmentCreatedEvent(),
                     CreateAppointmentRenamedEvent()
                 };
    var sut = CreateSut(events);
    
    // WHEN we ask to reschedule
    var newStartTime = DateTimeOffset.Now.AddHours(5);
    var newEndTime = DateTimeOffset.Now.AddHours(6);
    sut.Reschedule(newStartTime, newEndTime);
    
    // THEN does the AppointmentRescheduledEvent get published?
    sut.AppendedEvents.ShouldAllBeEquivalentTo(
        new[]
        {
            new AppointmentRescheduled(newStartTime, newEndTime)
        },
        config => config.RespectingRuntimeTypes());
}