Vue3 testing composition API with vuex in vitest - vue.js

Question

I'm having trouble getting a mock action to run using Vue3 while testing with vitest.
I have a component which calls out to a modularized vuex store that is imported into my component using the composition api. Something like the following.
export default defineComponent({
setup() {
const { doAction } = useModActions([
'doAction'
])
}
})
I use createNamespacedHelpers to setup my store module from the vuex-composition-helpers library.
After I use useStore with a Symbol key to setup the state of my store. I consume it in my application by doing
app.use(store, key)
To mock it in my tests I was trying the following
const actions = {
doAction: vi.fn()
}
const spy = vi.spyOn(actions, 'doAction')
const mockStore = createStore({
modules: {
mod: {
namespaced: true,
actions
}
}
})
const wrapper = mount(Component, {
global: {
provide: { [key]: mockStore }
}
})
But my spy is never called and my component always calls the original implementation. Is there a way to get all these pieces working together?

Answer 1

The mockStore here (from Vuex's createStore()) is an instance of a Vue plugin, which should be passed to the global.plugins mounting option (not global.provide):
// MyComponent.spec.js
import { describe, it, expect, vi } from 'vitest'
import { mount } from '#vue/test-utils'
import { createStore } from 'vuex'
import MyComponent from '../MyComponent.vue'
describe('MyComponent', () => {
it('button calls doAction', async () => {
const actions = {
doAction: vi.fn(),
}
const mockStore = createStore({
modules: {
myModule: {
namespaced: true,
actions,
},
},
})
const wrapper = mount(MyComponent, {
global: {
plugins: [mockStore], // 👈
},
})
await wrapper.find("button").trigger("click")
expect(actions.doAction).toHaveBeenCalled()
})
})
demo