public void SaveAndReturn() { var paymentRequest = new PaymentRequest { CardNumber = "1234123412341234", CardHolderName = "JOHN DOE", ExpiryDate = "10/20", Amount = 123.12, Currency = "GBP", CVV = "123" }; var paymentResponse = new PaymentResponse { Id = Guid.NewGuid(), Status = Status.Authorized }; var paymentInfo = new PaymentInfo(paymentRequest, paymentResponse); var memoryStorage = new MemoryStorage(); memoryStorage.SavePaymentInfo(paymentInfo); var returnedObject = memoryStorage.GetPaymentInfo(paymentResponse.Id); Assert.Equal(paymentRequest.CardHolderName, returnedObject.Request.CardHolderName); var nullObject = memoryStorage.GetPaymentInfo(Guid.NewGuid()); Assert.Null(nullObject); }