Jest Test Babel Error: Plugin/Preset files are not allowed to export objects

Question

我使用的是最新的（2017 年 12 月） 堆栈的依赖项。当我用 Jest 尝试同构反应测试时，测试套件不断失败并出现以下错误：

* Test suite failed to run
[BABEL] /__tests__/router.test.js: Plugin/Preset files are not allowed to
export objects, only functions.

这是我的依赖项：

"dependencies": {
    "axios": "^0.17.1",
    "babel-polyfill": "^6.26.0",
    "cors": "^2.8.4",
    "express": "^4.16.2",
    "react": "^16.1.1",
    "react-dom": "^16.1.1",
    "react-router-dom": "^4.2.2"
  },
  "devDependencies": {
    "@babel/core": "^7.0.0-beta.35",
    "babel-cli": "^6.26.0",
    "babel-core": "^7.0.0-bridge.0",
    "babel-eslint": "^8.0.2",
    "babel-jest": "^22.0.1",
    "babel-loader": "^7.1.2",
    "babel-preset-env": "^1.6.1",
    "babel-preset-react": "^6.24.1",
    "enzyme": "^3.2.0",
    "enzyme-adapter-react-16": "^1.1.0",
    "enzyme-to-json": "^3.2.2",
    "eslint": "^4.11.0",
    "eslint-plugin-react": "^7.5.1",
    "html-webpack-plugin": "^2.30.1",
    "jest": "^21.2.1",
    "nodemon": "^1.11.0",
    "parallelshell": "^3.0.2",
    "react-test-renderer": "^16.2.0",
    "regenerator-runtime": "^0.11.1",
    "supertest": "^3.0.0",
    "webpack": "^3.8.1",
    "webpack-dev-server": "^2.9.4"
  },
  "peerDependencies": {
    "babel-core": "^7.0.0-0"
  }

.babelrc :

{
  "presets": [
    "env",
    "react",
  ]
}

有人知道为什么 Jest 不会运行吗？

Answer 1

babel bridge is meant to cover any issues between 6 and 7

这 100% 不是 bridge 包的作用。它所做的只是允许使用 babel-core 的工具传递给 @babel/core。整个包是this single line of code.

如果您使用的是 @babel/core，则需要使用适用于 Babel 7 的插件。这意味着 babel-preset-react 应更改为 @babel/preset-react，@babel/preset-env 也应如此你的 .babelrc 应该是：

{
  "presets": [
    "@babel/env",
    "@babel/react",
  ]
}

同理，babel-polyfill应该是@babel/polyfill。

None 其中有详细记录，因为 Babel 7 仍然是一个不稳定的测试版。

Answer 2

{
    "presets": [
        "env",
        "react"
    ],
    "test": [
        "jest"
    ]
}

将 "test" 的最后一段代码添加给您 babel.rc 这是我的 .babelrc 代码供参考

   {
    "presets": [
        "env",
        "react"
    ],
    "plugins": [
        "transform-class-properties",
        "transform-object-rest-spread"
    ],
    "test": [
        "jest"
    ]
}

这是我的命令行输出

Test Suites: 1 passed, 1 total
Tests:       1 passed, 1 total
Snapshots:   0 total
Time:        9.264s
Ran all test suites.
Done in 12.99s.

Answer 3

I met the same challenge while configuring jest to work with babel-6.

See complete explanation here

但总而言之，--devDependencies 的这种组合对我有用，我设置了 babel-jest 来转换我的 **.js 文件：

// package.json

  "devDependencies": {
    "babel-core": "6.26.0",
    "babel-jest": "21.2.0",
    "babel-loader": "7.1.2",
    "babel-preset-env": "1.6.0",
    "babel-preset-react": "6.24.1",
    "babel-preset-stage-0": "6.24.1",
    "jest": "21.2.1",
    "webpack": "3.6.0"
  },
  "jest": {
    "transform": {
      "^.+\.jsx?$": "babel-jest"
    }
  }

// .babelrc

{
  "presets": [
    "env",
    "stage-0",
    "react"
  ]
}

Jest Test Babel Error: Plugin/Preset files are not allowed to export objects

Jest Test Babel Error: Plugin/Preset files are not allowed to export objects

reactjs

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isomorphic-javascript

babeljs