Vue3 / Vuex State is empty when dispatching action inside of lifecycle hook inside of test - vue.js

Question

We're using the composition API with Vue 3.
We have a Vuex store that, amongst other things, stores the currentUser.
The currentUser can be null or an object { id: 'user-uuid' }.
We're using Vue Test Utils, and they've documented how to use the store inside of tests when using the Composition API. We're using the store without an injection key, and so they document to do it like so:
import { createStore } from 'vuex'
const store = createStore({
// ...
})
const wrapper = mount(App, {
global: {
provide: {
store: store
},
},
})
I have a component and before it is mounted I want to check if I have an access token and no user currently in the store.
If this is the case, we want to fetch the current user (which is an action).
This looks like so:
setup() {
const tokenService = new TokenService();
const store = useStore();
onBeforeMount(async () => {
if (tokenService.getAccessToken() && !store.state.currentUser) {
await store.dispatch(FETCH_CURRENT_USER);
console.log('User: ', store.state.currentUser);
}
});
}
I then have a test for this that looks like this:
it('should fetch the current user if there is an access token and user does not exist', async () => {
localStorage.setItem('access_token', 'le-token');
await shallowMount(App, {
global: {
provide: {
store
}
}
});
expect(store.state.currentUser).toStrictEqual({ id: 'user-uuid' });
});
The test fails, but interestingly, the console log of the currentUser in state is not empty:
console.log src/App.vue:27
User: { id: 'user-uuid' }
Error: expect(received).toStrictEqual(expected) // deep equality
Expected: {"id": "user-uuid"} Received: null
Despite the test failure, this works in the browser correctly.
Interestingly, if I extract the logic to a method on the component and then call that from within the onBeforeMount hook and use the method in my test, it passes:
setup() {
const tokenService = new TokenService();
const store = useStore();
const rehydrateUserState = async () => {
if (tokenService.getAccessToken() && !store.state.currentUser) {
await store.dispatch(FETCH_CURRENT_USER);
console.log('User: ', store.state.currentUser);
}
};
onBeforeMount(async () => {
await rehydrateUserState();
});
return {
rehydrateUserState
};
}
it('should fetch the current user if there is an access token and user does not exist', async () => {
localStorage.setItem('access_token', 'le-token');
await cmp.vm.rehydrateUserState();
expect(store.state.currentUser).toStrictEqual({ id: 'user-uuid' });
});
Any ideas on why this works when extracted to a method but not when inlined into the onBeforeMount hook?