Discussion on: Mocking redux useSelector-hook

[tim.rohrer]

Another dev (way more experienced than me) also mocks useSelector.

I would like to see the "official" way work, but so far I'm still stuck.

In my component, a useSelector that includes the callback definition works. However, any useSelector that requires an imported callback seems to remain undefined.

This works:

  let demoTrip = useSelector(
    (state: RootState) => state.trips.allTrips[demoTripId]
  );

This returns undefined:

import { selectChosenMappingService } from '../system/systemSlice';  
...
const mappingServiceName = useSelector(selectChosenMappingService);

And from my slice:

export const selectChosenMappingService = (
  state: SystemState
): MappingService => state.chosenMappingService;

I remain confused.

[tim.rohrer]

I am happy to report that my issue was a mistake in my definitions of my selector functions in my slice. Turns out I needed to type as RootState and then include the reducer in the return (i.e., state.system.chosenMappingService).