SagaTestError: call expectation unmet:

[WillyRamirez]

Hi, I am testing if a yield call has been executed. I receive this error which I probably misunderstand, but as far as I can tell the function is called with the same parameters in both the saga and the test file.

Does anyone know why the expectation is unmet?

Let me know if I need to post the saga/test suite.

` SagaTestError: call expectation unmet:

Expected
--------
{ '@@redux-saga/IO': true,
  combinator: false,
  type: 'CALL',
  payload: 
   { context: null,
     fn: 
      { [Function: mockConstructor]
        _isMockFunction: true,
        getMockImplementation: [Function],
        mock: [Getter/Setter],
        mockClear: [Function],
        mockReset: [Function],
        mockRestore: [Function],
        mockReturnValueOnce: [Function],
        mockResolvedValueOnce: [Function],
        mockRejectedValueOnce: [Function],
        mockReturnValue: [Function],
        mockResolvedValue: [Function],
        mockRejectedValue: [Function],
        mockImplementationOnce: [Function],
        mockImplementation: [Function],
        mockReturnThis: [Function],
        mockName: [Function],
        getMockName: [Function] },
     args: [ { user: [Object] } ] } }

Actual:
------
1. { '@@redux-saga/IO': true,
  combinator: false,
  type: 'CALL',
  payload: 
   { context: null,
     fn: 
      { [Function: mockConstructor]
        _isMockFunction: true,
        getMockImplementation: [Function],
        mock: [Getter/Setter],
        mockClear: [Function],
        mockReset: [Function],
        mockRestore: [Function],
        mockReturnValueOnce: [Function],
        mockResolvedValueOnce: [Function],
        mockRejectedValueOnce: [Function],
        mockReturnValue: [Function],
        mockResolvedValue: [Function],
        mockRejectedValue: [Function],
        mockImplementationOnce: [Function],
        mockImplementation: [Function],
        mockReturnThis: [Function],
        mockName: [Function],
        getMockName: [Function] },
     args: [ { user: [Object] } ] } }`

[maxammann]

Having a similar case with jest mocking. not sure yet why they dont match

[jp928]

@maxammann do you mind to post your test case?

[maxammann]

The reason for this is that redux-saga-test-plan probably checks for identify (===) when comparing the fn and arguments in a CALL effect comparision.

Now, jest is a bit crazy when it comes to mocking modules. It has a feature to reset the modules (jest.resetModules()). If you import a function from the same location before that and after that it will not the identical.

So after a call to jest.resetModules() you have to reimport EVERY module you use in the expect code. With out this call the test will fail.

[maxammann]

It would be cool if the serializer could show that the arguments serialize to the same string but have a different identity.

[steffenkleinle]

As a workaround it is also possible to use the .like property which does not fail if it is not the same identity, e.g. expectSaga(foo, bar).call.like(baz, qux).run()

[mdenysov]

As a workaround it is also possible to use the .like property which does not fail if it is not the same identity, e.g. expectSaga(foo, bar).call.like(baz, qux).run()

Can you please give a more detailed example of using .like with expectSaga?

[steffenkleinle]

As a workaround it is also possible to use the .like property which does not fail if it is not the same identity, e.g. expectSaga(foo, bar).call.like(baz, qux).run()

Can you please give a more detailed example of using .like with expectSaga?

Sure, see the docs here: https://github.com/jfairbank/redux-saga-test-plan/blob/7f78a0742f94c67a221a9a1370b65f65e38b66b6/docs/integration-testing/partial-matching.md