react_hook_component_test.js

//
// Our redux component to test
//

export default function ProfileComponent (props) {

  const profile = useMySelector(state => state.profile, props)
  
  // Invariant Violation: could not find react-redux context value; please ensure the component is wrapped in a <Provider>
  // const profile = useSelector(state => state.profile)

  return (
    <View>
      { profile.isLoaded &&
        <ProfileItem data={ profile.data } />
      }
      ...
    </View>  
  )
}

//
// useMySelector wrapper
//

export function useMySelector(selector, props) {
  if (props && props.mockedState) {
    return props.mockedState
  }
  return useSelector(selector)
}

//
// Test
//

describe("ProfileComponent", () => {
  describe("when is loaded", () => {
    const state = {
      isLoaded: true,
      data: { ... }
    }

    const component = TestRenderer.create(<ProfileComponent mockedState={ state } />).root

    it("should render ProfileItem", () => {
      expect(component.findByType(ProfileItem))
    })
    
    it("should pass data to ProfileItem", () => {
      expect(component.findByType(ProfileItem).props.data).toEqual(state.data)
    })
  })
})