找不到相对于目录的预设“ module：metro-react-native-babel-preset”

Question

我正在尝试运行测试套件，但是出现以下错误：

Couldn't find preset "module:metro-react-native-babel-preset" relative to directory "/Users/dan/Sites/X"

      at node_modules/babel-core/lib/transformation/file/options/option-manager.js:293:19
          at Array.map (<anonymous>)
      at OptionManager.resolvePresets (node_modules/babel-core/lib/transformation/file/options/option-manager.js:275:20)
      at OptionManager.mergePresets (node_modules/babel-core/lib/transformation/file/options/option-manager.js:264:10)
      at OptionManager.mergeOptions (node_modules/babel-core/lib/transformation/file/options/option-manager.js:249:14)
      at OptionManager.init (node_modules/babel-core/lib/transformation/file/options/option-manager.js:368:12)
      at File.initOptions (node_modules/babel-core/lib/transformation/file/index.js:212:65)
      at File.initOptions (node_modules/ts-jest/dist/util/hacks.js:23:43)
      at new File (node_modules/babel-core/lib/transformation/file/index.js:135:24)
      at Pipeline.transform (node_modules/babel-core/lib/transformation/pipeline.js:46:16)

这是我在jest中的package.json配置：

"jest": {
    "preset": "react-native",
    "moduleFileExtensions": [
      "ts",
      "tsx",
      "js",
      "jsx",
      "json"
    ],
    "transform": {
      "^.+\\.(js)$": "<rootDir>/node_modules/react-native/jest/preprocessor.js",
      "\\.(ts|ts)x?$": "ts-jest"
    },
    "testRegex": "/src/.*.spec.(js|ts|tsx)?$",
    "globals": {
      "ts-jest": {
        "useBabelrc": true
      }
    }
  }

如果需要，这是babelrc

的内容

{
  "presets": ["module:metro-react-native-babel-preset"],
  "plugins": [
    [
      "module-resolver",
      {
        "alias": {
          "~": "./src"
        }
      }
    ]
  ]
}

Answer 1

This issue在撰写本文时保持打开状态。

用户对修复程序的理解似乎是好坏参半，但这两个对我有用：

选项1：将.babelrc更改为.babelrc.js

只需将.babelrc重命名为.babelrc.js或babel.config.js。

不要忘记将module.exports =添加到文件的开头。

这解决了我开玩笑的问题，但为我破坏了其他eslint插件。

选项2：将转换添加到Jest配置

对于选项2，我认为它可以通过在所有javascript文件上手动调用react-native预处理程序来解决此问题。

transform: { '^.+\\.js$': '<rootDir>/node_modules/react-native/jest/preprocessor.js' }

如果没有单独的Jest配置文件，则可以将其添加到package.json中，例如...

{
  "jest": {
    transform: { 
      "^.+\\.js$": "<rootDir>/node_modules/react-native/jest/preprocessor.js" 
    }
  }
}

Answer 2

我在控制台中有相同的警告。我通过运行以下代码对其进行了修复：

npm i metro-react-native-babel-preset --save-dev