Babel 7:转换模块后未捕获的ReferenceError

Question

我的Chrome扩展程序项目使用https://github.com/tfoxy/chrome-promise/blob/master/chrome-promise.js中的Chrome-Promise模块,以宣传Chrome API的回调式功能.

使用Babel 6实现项目的传输一直很好.最近我搬到了Babel 7.从那时起,当我允许通过Babel转换chrome-promise.js文件时,这会导致运行扩展时出现" 未捕获的ReferenceError:ChromePromise未定义 "错误.当我离开chrome-promise.js时,该程序运行良好,未经传输.

这是我的webpack配置js文件的摘录:

module.exports = {
  mode: 'production',
  entry: {
    cs: ['./build/cs.js'],
    bg: ['./build/bg.js'],
    popup: ['./build/popup.js'],
    chromepromise: ['./build/chromepromise.js']
  },
  output: {
    path: path.join(__dirname, 'build'),
    filename: '[name].js'
  },
  module: {
    rules: [{ 
      test: /\.js$/, 
      exclude: [/node_modules/],
      loader: "babel-loader" 
    }]
  },

和我的一个带有Babel设置的package.json:

{
  "name": "Test_CRX",
  "version": "1.0.0",
  "main": "cs.js",
  "scripts": {
    "build": "node build",
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "description": "",
  "dependencies": {
    "@babel/runtime": "^7.1.2",
    "archiver": "^3.0.0",
    "babel-polyfill": "^6.26.0",
    "babel-regenerator-runtime": "^6.5.0",
    "chrome-promise": "^3.0.1",
    "terser": "^3.10.1"
  },
  "devDependencies": {
    "@babel/core": "^7.1.2",
    "@babel/plugin-proposal-decorators": "^7.1.2",
    "@babel/plugin-proposal-function-bind": "^7.0.0",
    "@babel/plugin-transform-modules-umd": "^7.1.0",
    "@babel/plugin-transform-regenerator": "^7.0.0",
    "@babel/plugin-transform-runtime": "^7.1.0",
    "@babel/preset-env": "^7.1.0",
    "@babel/preset-react": "^7.0.0",
    "babel-loader": "^8.0.4",
    "babel-plugin-add-module-exports": "^1.0.0",
    "shelljs": "^0.8.1",
    "terser-webpack-plugin": "^1.1.0",
    "uglifyjs-webpack-plugin": "^2.0.1",
    "webpack": "^4.20.2",
    "webpack-cli": "^3.1.2"
  },
  "babel": {
    "presets": [
      [
        "@babel/env",
        {
          "targets": {
            "chrome": 60
          }
        }
      ],
      "@babel/react"
    ],
    "plugins": [
    ]
  }
}

注意:虽然我使用Terser来缩小JS代码,但是当我停用它时仍会出现错误.

编辑 查看我在github.com/Steve06/chrome-promise-babel-7-issue-repo上制作的最小回购

Answer 1

@babel/env默认情况下，预设将文件转换为commonjs，这要求转换后的文件包含在require或中import。为了使其与您的 Chrome 扩展兼容，您需要将文件转译为umd模块。把这个放在你的package.json：

"presets": [
  [
    "@babel/env",
    {
      "targets": {
        "chrome": 60,
        "modules": "umd"
      }
    }
  ]
],

您还应该知道它source/chrome-promise.js已经是一个umd模块，因此实际上不需要转译。