如何使用 Webpack 5 和 Babel 7 创建 IE11 Bundle

Question

我们如何将现代 JavaScript 编译成可与 Internet Explorer 11 (ie11) 一起使用的向后兼容的 JavaScript 包？具体来说，我们如何使用最新版本的 Webpack 5 和 Babel 7 做到这一点？

Answer 1

这是我可以创建的最小配置，其中包含一个测试文件，用于使用 IE 11 进行测试。Download on GitHub。

package.json

{
  "browserslist": [
    "ie 11"
  ],
  "scripts": {
    "dev":   "webpack -w",
    "build": "webpack"
  },
  "devDependencies": {
    "@babel/core": "^7.12.9",
    "@babel/preset-env": "^7.12.7",
    "babel-loader": "^8.2.2",
    "core-js": "^3.8.0",
    "webpack": "^5.8.0",
    "webpack-cli": "^4.2.0"
  }
}

webpack.config.js

module.exports = {
  entry: './index.js',
  module: {
    rules: [{
      test: /\.m?js$/,
      exclude: /node_modules/,
      use: {
        loader: 'babel-loader',
        options: {
          presets: [
            ['@babel/preset-env', {
              useBuiltIns: 'usage',
              corejs: 3
            }]
          ]
        }
      }
    }]
  }
}

Greeting.js

export default '2020 has been one hell of a year!'

index.js

/* 
 * Test that uses modern JavaScript and will be compiled to work in IE 11
 */
import greeting from './Greeting'

window.addEventListener('load', async () => {
  const o = {
    greeting: await Promise.resolve(greeting)
  }

  console.log(
    o,
    Object.entries(o),
    Object.keys(o),
    Object.values(o),
  )
})