Error with reactjs App.test.js

Question

我在尝试为 App.test 运行 npm.test 时收到此错误.js这是您在安装 reactjs 时得到的。关于如何解决这个问题的任何想法？我现在添加了一些额外的代码等。

> client@0.1.0 test /Users/filipmyllari/Documents/1DV430/fm222hp- 
project/client
react-scripts test --env=jsdom
>2018-05-29 16:26 node[535] (FSEvents.framework) FSEventStreamStart: 
register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2018-05-29 16:26 node[535] (FSEvents.framework) FSEventStreamStart: 
register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
events.js:182
throw er; // Unhandled 'error' event
^
>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.

这是 package.json 文件

{
"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"
}
}

代码如下(App.test.js(

import React from 'react'
import ReactDOM from 'react-dom'
import App from './App'
it('renders without crashing', () => {
const div = document.createElement('div')
ReactDOM.render(<App />, div)
})
describe('Addition', () => {
it('knows that 2 and 2 make 4', () => {
expect(2 + 2).toBe(4);
});
});

Answer 1

这是使用 Jest 进行测试时的常见问题。

我建议您按照 Jest 问题 1767 中的建议安装watchman。

brew install watchman

安装任何测试后应该没有问题，它已经解决了我和我的一些同事计算机上的此类问题，因此我相信它也值得您尝试。

---

此外，对问题的一些最新响应建议更新 Jest 以省略错误：

最终，更新到 Jest 23.1.0 解决了这个问题。 (转页(