Rollup报错，提示关闭模块转换

Question

我在用Jest测试JavaScript脚本，使用了ES6 Modules，所以用babel来转换ESM到CommonJS，但是Rollup打包的时候提示我关闭。现在打开了之后就不能跑Rollup，关闭了就不能跑Jest里的ESM。请问各位是如何解决的呢？

[!] (babel plugin) Error: It looks like your Babel configuration specifies a module transformer. Please disable it. See https://github.com/rollup/rol... for more information

Answer 1

babel可以配置env

{
  "env": {
    "test": {
      "presets": ["env"]
    },
    "production": {
      "presets": [
        ["env",
        {
          "modules": false
        }]
      ]
    }
  },
  "ignore": [
    "dist/*.js"
  ]
}

源自：.babelrc#env-option

然后，可以在npm scripts里配置BABEL_ENV

"scripts": {
  "test": "cross-env BABEL_ENV='test' jest --watchAll --coverage",
  "prettier": "prettier --write --no-semi {.,test}/*.js",
  "build": "cross-env BABEL_ENV='production' rollup -c"
}