reactjs - 在 React 和 Webpack 项目上从 "babel-preset-es2015"转换到 "babel-preset-env"时出现问题

Question

我有一个一直在使用 babel-preset-es2015 的 React 项目，它使用 webpack 构建得很好，但是自从我搬到了 babel-preset-env 模块构建失败。

出现此错误消息:

ERROR in ./src/index.js
Module build failed: Error: Couldn't find preset "es2015" relative to directory "/path/to/project"
    at /path/to/project/node_modules/babel-core/lib/transformation/file/options/option-manager.js:293:19
    at Array.map (<anonymous>)
    at OptionManager.resolvePresets (/path/to/project/node_modules/babel-core/lib/transformation/file/options/option-manager.js:275:20)
    at OptionManager.mergePresets (/path/to/project/node_modules/babel-core/lib/transformation/file/options/option-manager.js:264:10)
    at OptionManager.mergeOptions (/path/to/project/node_modules/babel-core/lib/transformation/file/options/option-manager.js:249:14)
    at OptionManager.init (/path/to/project/node_modules/babel-core/lib/transformation/file/options/option-manager.js:368:12)
    at File.initOptions (/path/to/project/node_modules/babel-core/lib/transformation/file/index.js:212:65)
    at new File (/path/to/project/node_modules/babel-core/lib/transformation/file/index.js:135:24)
    at Pipeline.transform (/path/to/project/node_modules/babel-core/lib/transformation/pipeline.js:46:16)
    at transpile (/path/to/project/node_modules/babel-loader/lib/index.js:50:20)
    at Object.module.exports (/path/to/project/node_modules/babel-loader/lib/index.js:175:20)

以下是我的 webpack 配置:

工作(使用 babel-preset-2015)

module.exports = {
  ...
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: [
              'es2015',
              'react',
              'stage-1']
          }
        }
      }
    ]
  },
  ...
};

不起作用(使用 babel-preset-env)

module.exports = {
  ...
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: [
              'env',
              'react',
              'stage-1']
          }
        }
      }
    ]
  },
  ...
};

package.json 依赖:

"babel-core": "^6.26.0",
"babel-loader": "^7.1.2",
"babel-preset-env": "^1.6.0"

Answer 1

所以我添加了一个 .babelrc 文件并将加载器选项移到那里，现在一切似乎都正常了。仍然不确定为什么它在 webpack 模块中不起作用。

网页包

module.exports = {
  ...
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: 'babel-loader'
      }
    ]
  },
  ...
};

.babelrc

{
  "presets": [
    "env",
    "react",
    "stage-1"
  ]
}