title: Error with reactjs App.test.js
body: <p>I get this error while trying to run npm.test for the App.test.js that you get when installing reactjs. Any thoughts on how to solve this? I've added some extra code etc now.</p>
  
  <pre><code>&gt; client@0.1.0 test /Users/filipmyllari/Documents/1DV430/fm222hp- 
  project/client
  react-scripts test --env=jsdom
  
  &gt;2018-05-29 16:26 node[535] (FSEvents.framework) FSEventStreamStart: 
  register_with_server: ERROR: f2d_register_rpc() =&gt; (null) (-22)
  2018-05-29 16:26 node[535] (FSEvents.framework) FSEventStreamStart: 
  register_with_server: ERROR: f2d_register_rpc() =&gt; (null) (-22)
  events.js:182
    throw er; // Unhandled 'error' event
    ^
  
  &gt;Error: Error watching file for changes: EMFILE
  at _errnoException (util.js:1019:11)
  at FSEvent.FSWatcher._handle.onchange (fs.js:1360:9)
  npm ERR! Test failed.  See above for more details.
  </code></pre>
  
  <p>Here is the package.json file</p>
  
  <pre><code>{
   "name": "client",
   "version": "0.1.0",
   "private": true,
   "dependencies": {
   "add": "^2.0.6",
   "babel-jest": "^23.0.1",
   "babel-preset-env": "^1.7.0",
   "babel-preset-react": "^6.24.1",
   "firebase": "^4.13.1",
   "jest": "^23.0.1",
   "lodash": "^4.17.5",
   "react": "^16.3.1",
   "react-dom": "^16.3.1",
   "react-router-dom": "^4.2.2",
   "react-scripts": "1.1.4",
   "react-test-renderer": "^16.4.0",
   "yarn": "^1.7.0"
   },
   "scripts": {
   "start": "react-scripts start",
   "build": "react-scripts build",
   "test": "react-scripts test --env=jsdom",
   "eject": "react-scripts eject"
  },
  "devDependencies": {
   "enzyme": "^3.3.0",
   "react-addons-test-utils": "^15.6.2"
  }
  }
  </code></pre>
  
  <p>The code comes below here (App.test.js)</p>
  
  <pre><code>import React from 'react'
  import ReactDOM from 'react-dom'
  import App from './App'
  
  it('renders without crashing', () =&gt; {
    const div = document.createElement('div')
    ReactDOM.render(&lt;App /&gt;, div)
  })
  
  describe('Addition', () =&gt; {
    it('knows that 2 and 2 make 4', () =&gt; {
      expect(2 + 2).toBe(4);
    });
  });
  </code></pre>