Default `EnhancedStore.dispatch` unusable in TS in 1.8.0?

1.8.0’s changes to middleware dispatch types apparently mean that the default EnhancedStore.dispatch is typed as never in TypeScript.

import { CombinedState, configureStore, EnhancedStore } from '@reduxjs/toolkit';

let store: EnhancedStore<CombinedState<{ name: string }>> | undefined;
store = configureStore({ reducer: (state) => state || { name: 'Test'} });
store.dispatch({});

In RTK 1.8.0, this results in the following TypeScript error:

This expression is not callable.
  Type 'never' has no call signatures. ts(2349)

In RTK 1.7.2, it compiles without errors.

I can work around this by specifying my own middleware type argument to EnhancedStore or by inferring the type with typeof, but that feels much more awkward.

Thank you.

[markerikson]

Okay, the issue here is the use of a separate ConfigureStoreOptions. You’ve erased any actual types that could be inferred.

Please don’t write that separately. If you do everything inline in configureStore, the types are correct:

export const store = configureStore({
  reducer: {
    [feedbackSlice.name]: feedbackSlice.reducer
  },
  middleware: (getDefaultMiddleware) => getDefaultMiddleware().concat()
});

It looks like the main reason you’re doing that is to make the devTools option configurable. I’d suggest just having a separate let devTools boolean and conditionally assign to that, then pass it as an argument to configureStore.

[phryneas]

Generally, when using RTK you should never declare an explicit type for a variable. That is erasing all type information until there is only the info “Yeah, this has the shape of a configuration. Maybe there are reducers in there. Maybe middleware.” is left.