Question

我的jest测试错误，但我的应用程序转换（webpack）并运行没有错误。我最近切换到babel-preset-env，但我仍然得到同样的错误。

相关的package.json：

"jest": "^20.0.4",
"jest-fetch-mock": "^1.0.8",
"babel-core": "^6.22.1",
"babel-jest": "^20.0.3",
"babel-preset-es2015": "^6.22.0",
"babel-preset-stage-0": "^6.22.0",

.babelrc

{
  "presets": ["es2015", "stage-0"],
  "plugins": [
    ["inferno", {"imports": true}],
    ["transform-es2015-classes", {"loose": true}]
  ],
  "env": {
    "test": {
      "presets": ["es2015", "stage-0"]
    }
  }
}

src / js / modules / ui / components / UIObject / index.jsx直到第17行

import TwitterComponent from './twitter';
import AdComponent, { networks } from './ad';
import RssComponent from './rss';
import WwwComponent from './www';
import connector from '../../connector';
const types = ['twitter', 'ads', 'rss', 'www'];
const getTitleByType = (type, data) => {
    const titles = {
        twitter: data['data-widget-id'],
        ad: `${networks[data.network]} (${data.key})`,
        ads: `${networks[data.network]} (${data.key})`,
        rss: data.url,
        www: data.url
    };
    return titles[type];
};
const Ad = connector(AdComponent, ['noSubmit', 'ads']);
...

../../ connector.js

import { connect } from 'inferno-redux';
import { actions } from './reducers/main';
import { bindActionCreators } from 'redux';
import Immutable from 'seamless-immutable';
const connector = (component, keys = null) => {
    const mapDispatchToProps = dispatch => {
        return bindActionCreators(Object.assign({}, actions), dispatch);
    };
    const mapStateToProps = state => {
        const _state = {};
        const stateKeys = Object.keys(Immutable.asMutable(state.main));
        for (let key of stateKeys) {
            if ((Array.isArray(keys) && keys.includes(key)) || keys === null) {
                _state[key] = Immutable.getIn(state.main, [key]);
            }
        }
        return _state;
    };
    return connect(mapStateToProps, mapDispatchToProps)(component);
};
export { connector };
export default connector;

控制台输出：

FAIL  src/__tests__/modules/ui/components/Main/index.spec.jsx
  ● Test suite failed to run

    TypeError: (0 , _connector2.default) is not a function

      at Object.<anonymous> (src/js/modules/ui/components/UIObject/index.jsx:17:109)
      at Object.<anonymous> (src/js/modules/ui/components/UIObjectsComponent/index.jsx:2:43)
      at Object.<anonymous> (src/js/modules/ui/reducers/main.js:367:305)
      at Object.<anonymous> (src/js/modules/ui/connector.js:2:39)
      at Object.<anonymous> (src/js/modules/ui/components/Main/index.jsx:3:44)
      at Object.<anonymous> (src/__tests__/modules/ui/components/Main/index.spec.jsx:3:13)
          at <anonymous>
      at process._tickCallback (internal/process/next_tick.js:188:7)

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        14.381s

供参考：

github issue

Answer 1

您的代码中存在循环依赖关系。你可以在stacktrace中看到它：

at Object.<anonymous> (src/js/modules/ui/components/UIObject/index.jsx:17:109)
at Object.<anonymous> (src/js/modules/ui/components/UIObjectsComponent/index.jsx:2:43)
at Object.<anonymous> (src/js/modules/ui/reducers/main.js:367:305)
at Object.<anonymous> (src/js/modules/ui/connector.js:2:39)
at Object.<anonymous> (src/js/modules/ui/components/Main/index.jsx:3:44)
at Object.<anonymous> (src/__tests__/modules/ui/components/Main/index.spec.jsx:3:13)

从下到上：

connector.js:2:39此文件正在加载，并运行
```
import { actions } from './reducers/main';
```
加载更多文件
更多文件加载
UIObject/index.jsx:17:109此文件正在加载，然后运行
```
import connector from '../../connector';
```

但是这个循环不起作用。 connector.js在第3步之前停止运行，然后才到达

const connector = (component, keys = null) => {

意味着当它在步骤6中运行导入时，connector尚不存在。

在真正的ES6环境中，这段代码实际上会抛出异常，就像你做的那样

connector()
let connector = ...

但是Babel当前没有处理这些案件，所以价值只显示为undefined。

您必须重新编写代码，以便不存在此循环依赖。

babel，jest：TypeError：（0，_connector2.default）不是函数

1 个答案: