'state.merge is not a function' in react-native

Question

In my react-native app, I am using redux-persist to display data present in the store if the user is offline. But after adding redux-persist I am getting error state.merge is not a function. I think it's an error of Immutability. please help me to solve this problem.

rootChangeReducer.js

import * as types from '../actions/login/ActionTypes';
import Immutable from 'seamless-immutable';

const initialState = Immutable({
  root: undefined, // 'login' / 'after-login' / 'register'
});

//root reducer
export function root(state = initialState, action = {}) {

  switch (action.type) {

    case types.ROOT_CHANGED:
      return state.merge({
        root: action.root
      });

    default:
      return state;
  }
}

and configureStore.js

import { createStore, combineReducers, compose, applyMiddleware } from "redux";
import thunk from "redux-thunk";
import { persistStore, persistCombineReducers } from 'redux-persist';
import storage from 'redux-persist/es/storage';

import masjids from "./reducers/productReducer";
import { root } from "./reducers/rootReducer";


const config = {
  key: 'root',
  storage,
} 

const reducers = {
  root,
  masjids
}

const reducer = persistCombineReducers(config, reducers)

let composeEnhancers = compose;

if (__DEV__) {
  composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
}

const configureStore = () => {
  return createStore(reducer, composeEnhancers(applyMiddleware(thunk)));
};

export default configureStore;

Thanks in advance.

but why are you using merge? state doesn't seems to have any function like merge.! — Jaydeep Galani

kreysix kreysix · Accepted Answer · 2019-03-12T11:21:18

Just simply use the spread operator (...) to merge or append data into state, and then return the state. Like, return {...state,root:action.root} Or can also use the merge function in lodash

'state.merge is not a function' in react-native

1 Answers