JEST does not register function calls

I have simple component which triggers function 'display' on $communicates object. I want to be sure that this function have been called:

it('should display communicate', () => {
        const $communicates = {
            display() { return true }
        }
        const wrapper = shallowMount(Component, {
            mocks: {
                $communicates
            }
        })
        const spy = jest.spyOn(wrapper.vm.$communicates, 'display')
        // const spy = jest.spyOn($communicates, 'display') //also tried

        // ... code which triggers component method 'displayCommunicate' ...

        expect(spy).toHaveBeenCalled()
    })

and my component:

export default {
   methods: {
     displayCommunicate() {
        console.log('function executed') // 'function executed'
        this.$communicates.display('Blabla')
     }
   }
}

Jest shows me error

Expected mock function to have been called, but it was not called.