Correct typing with withCallState within custom feature

[jan-willem-baart]

Trying to use withCallState within withAutocomplete but can't manage to get the typing correct of the returned signalstore, see example. Any tips on how to get this working?

export type AutocompleteSignalStoreFeature<Collection extends string> =
  SignalStoreFeature<
    EmptyFeatureResult,
    EmptyFeatureResult & {
      state: NamedAutocompleteStateSlice<Collection> & NamedCallStateSlice<Collection>;
      props: NamedCallStateSignals<Collection>;
      computed: NamedCallStateComputed<Collection>;
    }
  >;

[rainerhahnekamp]

@jan-willem-baart

I don’t see an issue with giving TypeScript a little nudge in the right direction using type assertions. Your use case isn’t trivial, and even advanced features like withCallState rely on type assertions.

export function withAutocomplete<Collection extends string>(config: {
  collection: Collection;
}): AutocompleteSignalStoreFeature<Collection> {
  const { optionsKey, selectedOptionKey, selectedOptionIdKey, queryKey } =
    getNamedAutocompleteKeys(config);

  return signalStoreFeature(
    withState({
      [optionsKey]: [],
      [selectedOptionKey]: null,
      [selectedOptionIdKey]: '',
      [queryKey]: '',
    }),
    withCallState({ collection: config.collection })
  ) as AutocompleteSignalStoreFeature<Collection>;
}