public void CancelPayment_ShouldBeClosed()
            {
                var reason = "cancelled";

                paymentRequest.CancelPayment(reason);

                Assert.Equal(PaymentStatus.Closed, paymentRequest.Status);
                Assert.Equal(reason, paymentRequest.Reason);
            }
 public override void ChangePaymentStatus(PaymentRequest payment, string reason)
 {
     payment.CancelPayment(reason);
 }
 public void CancelPayment_ShouldThrow()
 {
     Assert.Throws <PaymentDomainException>(() => paymentRequest.CancelPayment("cancelled"));
 }