I am trying to test a nuxt page with vitest.

It has a child component toolbar which emits an event “on-filters-change”. When this event is triggered, the page calls a method “onFilter”. My test should verify this method is well called when the event happens:

describe('Test filtering', () => {
      let toolbar: Awaited<ReturnType<typeof wrapper.find>>;
      beforeAll(() => {
        toolbar = wrapper.findComponent('[data-unit="toolbar"]');
      });
      it('Should find the toolbar', async () => {
        expect(toolbar).toBeTruthy();
      });

      describe('First filter', () => {
        it('Should listen to the toolbar events', async () => {
          const spy = vi.spyOn(wrapper.vm, 'onFilter');
          // wrapper.vm.onFilter({ ... });
          await toolbar.vm.$emit('on-filters-change', { ... });
          expect(toolbar.emitted()['on-filters-change']).toBeTruthy(); // Ok

          expect(spy).toHaveBeenCalled(); // NOK
          spy.mockRestore();
        });
      });
    });

If I call myself the method “onFilter” (commented line), the test passes. I suppose this is due to an event detection issue ?
Or can the “onFilter” method being called after I looked if the spy has been called ?

I guess it is a common purpose so I am looking forward to master this test case … Thanks for your help