test_project/src/reducers/index.js

import thunk from 'redux-thunk';
import {createStore, combineReducers, applyMiddleware} from 'redux';
import { authReducer } from './authReducer';
import { promiseReducer } from './promiseReducer';
import { actionUserInfo } from '../actions';

const rootReducer = combineReducers({
    promiseReducer,authReducer
})
const store = createStore(rootReducer, applyMiddleware(thunk)) 
if(localStorage.authToken){
    store.dispatch(actionUserInfo())
}
store.subscribe(()=> console.log(store.getState()))

export default store