How to use createTestingPinia() when pinia it is used outside a component

[yakobe]

Imagine i have some code (eg a composable) that uses a store. I would like to test the code with jest and mock the store with createTestingPinia(). However, the actions of the store are not mocked and still call api's etc.

I imagine this is because my code does not know that it should be using the pinia created by createTestingPinia() and maybe creates it's own instance of pinia? Is it possible to somehow so that i can spy on an action to ensure it is called?

Many thanks ☺️

[posva]

You need to call setActivePinia() with the testing pinia for it to be used (https://pinia.vuejs.org/cookbook/testing.html#unit-testing-a-store)

[yakobe]

Thanks for getting back to me @posva 👍

Do you mean something like this in the jest test:

  it('calls `myStoreAction` on the Store', async () => {
	// Given
    const pinia = createTestingPinia()
    setActivePinia(pinia)
    const myStore = useMyStore()
    const myStoreAction = jest.spyOn(myStore, 'myStoreAction')

    // When
    await myFunctionUnderTest('some param')

    // Then
    expect(myStoreAction).toHaveBeenCalledTimes(1)
  })

Or have i misunderstood? With the above code the myStoreAction is not mocked and runs the real code with calls to APIs etc. I hoped with createTestingPinia() it would be mocked.

[posva]

Yes. You can pass an options object to createTestingPinia. Check the available options, there is one to stub actions. I think there is also an example in docs in the link I sent you

[yakobe]

Hi @posva

After some digging around, the option fakeApp: true seems to do what i need. I'm guessing it creates a fake app so we always get the same instance. Does that sound about right? Seems to work 😄.