Invalid mapStateToProps Argument in React-Redux

Question

I'm facing a problem with mapStateToProps argument. It seems a very simple error but I'm not able to figure out what's happening. Basically, what I'm trying to do is toggle a sidebar menu with react-redux and react saga. Everything works well but I'm getting the following error:

Uncaught Error: Invalid value of type object for mapStateToProps argument when connecting component Sidebar.

Appreciate any help:

Index app/js/index.js

import React from 'react';
import { render } from 'react-dom';
import { Provider } from 'react-redux';
import configureStore from '../store/configureStore';
import Canvas from '../components/Canvas/Canvas';

const store = configureStore();

render(
  <Provider store={store}>
    <Canvas />
  </Provider>,
  document.getElementById('app'),
);

Reducers

(Index) app/reducers/index.js

import { combineReducers } from 'redux';
import sidebar from './sidebar';

const rootReducer = combineReducers({
  sidebar,
});

export default rootReducer;

(Sidebar) app/reducers/sidebar.js

import {
  TOGGLE_SIDEBAR,
} from '../actions';

const sidebar = (state = { value: true }, action) => {
  switch (action.type) {
    case TOGGLE_SIDEBAR:
      debugger;
      return action.value;
    default:
      debugger;
      return state.value;
  }
}

export default sidebar;

Sagas

index.js app/sagas/index.js

import { fork } from 'redux-saga/effects';
import { watcher } from './watcher';

function* rootSaga() {
  yield [
    fork(watcher),
  ];
}

export default rootSaga;

sidebar.js app/sagas/sidebar.js

import { put } from 'redux-saga/effects';
import {
  TOGGLE_SIDEBAR,
} from '../actions';

export function* sidebar () {
  try {
    yield put ({ type: TOGGLE_SIDEBAR });
  } catch (err) {
    debugger;
  }
}

watcher.js app/sagas/watcher.js

import { takeEvery } from 'redux-saga/effects';
import { sidebar } from './sidebar';
import {
  TOGGLE_SIDEBAR,
} from '../actions';

export function* watcher() {
  try {
    yield takeEvery(TOGGLE_SIDEBAR, sidebar);
  } catch (err) { debugger; }
}

Actions app/actions/index.js

export const TOGGLE_SIDEBAR = 'TOGGLE_SIDEBAR';

export const toggleSidebar = (value) => ({
  type: TOGGLE_SIDEBAR,
  value,
});

Containers SidebarContainer.js app/containers/sidebarContainer.js

import { connect } from 'react-redux';
import {
  toggleSidebar as callToggleSidebar,
} from '../actions';
import Sidebar from '../components/Sidebar/Sidebar';

debugger;
const mapStateToProps = (state) => {
  debugger;
  return {
    open: state.sidebar,
  }
};

const mapDispatchToProps = dispatch => ({
  toggleSidebar: (val) => { dispatch(callToggleSidebar(val)); },
});

export default connect({
  mapStateToProps,
  mapDispatchToProps,
})(Sidebar);

Components

Sidebar.jsx app/components/Sidebar.jsx

import React from 'react';
import { PropTypes } from 'prop-types';
import './styles/styles.less';

const Sidebar = ({ open, toggleSidebar }) => (
  <div className={open ? 'sidebar sidebar-open' : 'sidebar sidebar-closed'}>
    <div className='show-hide-container'>
      <button onClick={() => toggleSidebar(!open)}>
        <i className="fa fa-arrow-right" aria-hidden="true" />
      </button>
    </div>
    Sidebar
  </div>
);

Sidebar.propTypes = {
  open: PropTypes.bool.isRequired,
  toggleSidebar: PropTypes.func.isRequired,
};

export default Sidebar;

Answer 1

export default connect(
  mapStateToProps,
  mapDispatchToProps,
)(Sidebar);

Please try, passing mapStateToProps and mapDispatchToProps as arguments instead of an object.

connect is a function expecting state and dispatch functions.

https://github.com/reactjs/react-redux/blob/master/docs/api.md#connectmapstatetoprops-mapdispatchtoprops-mergeprops-options