I don't follow. Under no circumstance would the test pass under invalid inputs, be it whether you use mocks, stubs, or even mockery (fakes?).
- Obviously it cannot pass while using mocks – a mock matches the real thing to every last detail. If it will fail while using the real thing, it will fail here as well.
- Obviously it cannot pass while using stubs – a stub matches the real thing, partially, to at least the minimum amount necessary for the sake of testing. If it will fail while using the real thing, it will fail here as well.
- Obviously it cannot pass while using mockery – mockery does not match the real thing in any way, but does require you to specify matching inputs with failure when they don't match. If it will fail while using the real thing, it will fail here as well.
I don't know what you are imagining, but I'm not convinced it is a thing. I mean, you could make it a thing - you can do anything your little heart desires, but there would be no reason to ever make it a thing.
Maybe we need some concrete tests to better illustrate what you are talking about?
https://stackoverflow.com/questions/3459287/whats-the-differ...
Stubs do not react based on their input parameters. However, even fakes have the issue of fault injection.
I don't want to just test valid inputs. I want to make sure I pass the correct inputs for the request parameters through to the dependencies. If pass 100.00 in the request but in my impl I pass 0.00 to the stub. The test will pass because the input is valid. But the implementation is not correct.
Also, mockery is just an alternative mocking api. There is nothing special here.
How would you test the case where the quota update fails with a stub? Here is mockery example again generated with chatgpt.
func TestHandleTransaction_QuotaUpdateFails(t *testing.T) {
// Create the mock services
mockAuth := new(mocks.AuthService)
mockPayment := new(mocks.PaymentService)
mockStorage := new(mocks.StorageService)
mockQuota := new(mocks.QuotaService)
mockNotification := new(mocks.NotificationService)
// Setup expectations
mockAuth.On("Authenticate", mock.Anything).Return("12345", nil)
mockQuota.On("CheckQuota", "12345").Return(true, nil) // Quota check passes
mockQuota.On("UpdateQuota", "12345", mock.AnythingOfType("int64")).Return(errors.New("quota update failed")) // Quota update fails
// No need to mock payment and storage as they should not be called if quota update fails
// Create the server with mock services
server := &Server{
Auth: mockAuth,
Payment: mockPayment,
Storage: mockStorage,
Quota: mockQuota,
Notification: mockNotification,
}
// Create a test request
transaction := TransactionRequest{
UserID: "12345",
AuthToken: "valid-token",
ProductID: "product123",
Price: 100.0,
Currency: "USD",
File: []byte("file data"),
}
requestBody, _ := json.Marshal(transaction)
request := httptest.NewRequest(http.MethodPost, "/transaction", bytes.NewReader(requestBody))
responseRecorder := httptest.NewRecorder()
// Call the endpoint
server.HandleTransaction(responseRecorder, request)
// Check the results
assert.Equal(t, http.StatusInternalServerError, responseRecorder.Code)
response := TransactionResponse{}
json.NewDecoder(responseRecorder.Body).Decode(&response)
assert.Equal(t, "error", response.Status)
assert.Contains(t, response.Message, "quota update failed")
// Assert that all expectations were met
mockAuth.AssertExpectations(t)
mockQuota.AssertExpectations(t)
// Assert no calls to payment and storage
mockPayment.AssertNotCalled(t, "Charge", mock.AnythingOfType("float64"), mock.AnythingOfType("string"), mock.AnythingOfType("string"))
mockStorage.AssertNotCalled(t, "Upload", mock.AnythingOfType("[]uint8"), "bucket-name", "key-name")
// No notification should be sent
mockNotification.AssertNotCalled(t, "SendNotification", "12345", mock.AnythingOfType("string"))
}I willingly accept your unconventional usage if it greases discussion, but the dictionary is right there. It records how most people use words. What mockery gives appears to be what most people consider a fake. It clearly does not fit the definition of mock. It arguably matches the definition of stub and I think you could reasonably call it that, but I posit that doesn't tell the whole story, which is no doubt why fake emerged.
That said, I don't know what your definitions are. You seem to flail around with them.
> Stubs do not react based on their input parameters.
All of mocks, stubs, and fakes react based on input...
> How would you test the case where the quota update fails with a stub?
... Although this seems like a poor example. It is not clear if the failure state is due to invalid input or due to some other issue.
This, I must say, makes for a really bad test. Tests are, first and foremost, the contract and documentation for your users. They are written so that other people can learn about the system and know what they can depend on during use. The self-validation offered by testing is there merely to ensure that what is written in the contract is true. –– Not that we were expecting anything more from ChatGPT, but this does, interestingly, indicate yet another problem with mockery. I hadn't even picked up on that one earlier. Glad we were able to keep the discussion going to learn more!
But, importantly, we lack necessary information to respond to your question. Perhaps you can clarify the intent here?
My suggestion is for you to provide code how you would test the same handler code and scenario using your methodology.
Show me a test that checks the error handling of quota check. Pretend the quota service is experiencing an outage on the second request you make to it.
type quotaNetworkFailure struct{ quotaSuccess }
func (quotaNetworkFailure) UpdateQuota() (bool, error) { return false, quota.ErrNetworkFailure }
func TestTransaction_QuotaUpdateNetworkFailure(t *testing.T) {
tx := &Transaction{
Auth: authSuccess{},
Payment: paymentSuccess{},
Storage: storageSuccess{},
Quota: quotaNetworkFailure{},
Notification: notificationSuccess{},
}
_, err := tx.Request("12345", "valid-token", "product123", 100.0, "USD", []byte("file data"))
if !errors.Is(quota.ErrNetworkFailure, err) {
t.Errorf("unexpected error: %v", err)
}
}
Yes, okay, you got me. That isn't the HTTP service anymore. But it should have never been. The transaction processing is not an HTTP concern. In fixing that, now you can make the HTTP end of things far less obtuse:
var errGeneralError = errors.New("general error")
type transactionFailure struct{}
func (transactionFailure) Request(id, token, productID string, amount float64 /* yikes */, currency string, file []byte) {
return false, errGeneralError
}
func TestBuy_Failure(t *testing.T) {
srv := httptest.NewServer(&Server{
Transaction: transactionFailure{},
})
defer srv.Close()
c := client.New(srv.URL)
_, err := c.Buy("product123")
if !errors.Is(transaction.ErrFailed, err) {
t.Errorf("unexpected error: %v", err)
}
}
type transactionNoProduct struct{}
func (transactionNoProduct) Request(id, token, productID string, amount float64 /* yikes */, currency string, file []byte) (bool, error) {
if productID != "product123" {
return true, nil
}
return false, transaction.ErrProductNotFound
}
func TestBuy_ProductNotFound(t *testing.T) {
srv := httptest.NewServer(&Server{
Transaction: transactionNoProduct{},
})
defer srv.Close()
c := client.New(srv.URL)
_, err := c.Buy("product123")
if !errors.Is(transaction.ErrProductNotFound, err) {
t.Errorf("unexpected error: %v", err)
}
}