How to mock a specific action to test a store

[leo-coco]

I am not able to test what seems to be a simple scenario.

Store

const useStore = defineStore('store', () => {
  const id = ref('id');
  const forceId = ref('forceId');

  function shouldReturnForceId() {
    return false;
  }

  function getId() {
    if (shouldReturnForceId()) {
      return forceId.value;
    }
    return id.value;
  }

  return {
    id,
    forceId,
    shouldReturnForceId,
    getId,
  };
});

Helper

const createTestStore = (stubActions: boolean) => {
  const pinia = createTestingPinia({
    stubActions,
  });
  setActivePinia(pinia);

  const store = useStore();

  return store;
};

Test

describe('Pinia Test', () => {
  describe('getId', () => {
    // DOES NOT WORK - stubAction to false and mocking shouldReturnForceId
    it('should return forceId if shouldReturnForceId is true', () => {
        const store = createTestStore(false);
        store.shouldReturnForceId = jest.fn(() => true);
        expect(store.getId()).toEqual('forceId');
    });
    
    // DOES NOT WORK - stubAction to true and mocking shouldReturnForceId
    it('should return forceId if shouldReturnForceId is true', () => {
      const store = createTestStore(true);
      store.shouldReturnForceId = jest.fn(() => true);
      expect(store.getId()).toEqual('forceId');
    });
  });
});

Question

How can I mock the behaviour of shouldReturnForceId, so I can adapt it to my different tests scenarios? Ideally after the creation of the store, or before but then without to re-write a whole store for each case