纱线测试失败 - 网络请求失败

Question

我使用 create-react-app 创建了一个 React 项目，但是当运行 yarn test 查看初始测试是否通过时，我得到

TypeError: Network request failed
    at XMLHttpRequest.xhr.onerror (/home/ubuntu/wonderland/hackernews/node_modules/whatwg-fetch/fetch.js:436:16)
    at XMLHttpRequest.callback.(anonymous function) (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/events/EventTarget-impl.js:289:32)
    at invokeEventListeners (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/events/EventTarget-impl.js:219:27)
    at invokeInlineListeners (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/events/EventTarget-impl.js:166:7)
    at EventTargetImpl._dispatch (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/events/EventTarget-impl.js:122:7)
    at EventTargetImpl.dispatchEvent (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/events/EventTarget-impl.js:87:17)
    at XMLHttpRequest.dispatchEvent (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/generated/EventTarget.js:61:35)
    at XMLHttpRequest.abort (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/xmlhttprequest.js:405:16)
    at Object.abort (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/xhr-utils.js:315:13)
    at RequestManager.close (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/living/nodes/Document-impl.js:146:21)
    at Window.close (/home/ubuntu/wonderland/hackernews/node_modules/jsdom/lib/jsdom/browser/Window.js:362:29)
    at JSDOMEnvironment.dispose (/home/ubuntu/wonderland/hackernews/node_modules/jest-environment-jsdom/build/index.js:44:19)
    at Promise.resolve.then (/home/ubuntu/wonderland/hackernews/node_modules/jest-cli/build/runTest.js:102:17)

我在 Cloud9 编辑器中工作，使用 ssh 连接到我在 AWS 中托管的开发服务器 (Ubuntu)。测试在我的本地机器上运行良好 (Ubuntu)。

感谢您的帮助！

Answer 1

我已经解决了我的问题。我正在阅读一本名为 "The Road to Learn React" 的书，我认为导致我出错的部分是我 fetch 来自外部 API 的数据。这本书忘记包含一个 fetch 的导入，就是这个：

import fetch from 'isomorphic-fetch'

然后，它像魅力一样解决了我的问题。

纱线测试失败 - 网络请求失败

Yarn test failing - Network request failed

cloud9-ide

reactjs

jestjs

create-react-app