title: ReferenceError: window is not defined. I got this error when I run npm test to unit testing by jest
body: <p>ReferenceError: window is not defined. I got this error when I run npm test to unit testing by jest. Error come from following code export function. Any one met this type of error and solved it?</p>
  
  <pre><code>import { createStore, applyMiddleware, compose, combineReducers } from 'redux';
  import thunk from 'redux-thunk';
  
  import rootReducer from '../modules/rootReducer';
  
      export function injectAsyncReducers(asyncReducers) {
    const injectReducers = Object.keys(asyncReducers).reduce((all, item) =&gt; {
      if (store.asyncReducers[item]) {
        delete all[item];
      }
  
      return all;
    }, asyncReducers);
  
    store.asyncReducers = Object.assign({}, store.asyncReducers, injectReducers);
    replaceReducers(rootReducer);
  }
  </code></pre>