public void Create_Appointment_returns_view_if_the_model_is_invalid()
{
var controller = GetAppointmentsController(new InMemoryAppointmentRepository());
controller.ModelState.AddModelError("", "Name is required");
var appointment = MakeAppointment();
var result = controller.Create(appointment) as ViewResult;
Assert.That(result.ViewName, Is.EqualTo("Create"));
}