Babel plugin not being recognized when trying to run Jest

Question

I'm just starting to write some Jest tests but have immediately run into an "unknown plugin" error in what otherwise appeared to be a fully working Webpack/Babel setup that functions fine at the npm run dev / npm run build stage.

Specifically, I'm getting ReferenceError: Unknown plugin "@babel/transform-async-to-generator" specified in "C:\\\\Users\\\\scott\\\\path\\\\to\\\\ThisProject\\\\.babelrc" at 0, attempted to resolve relative to "C:\\\\Users\\\\scott\\\\path\\\\to\\\\ThisProject"

(Error reads that way as I'm in Git Bash on Windows.)

I definitely have @babel/plugin-transform-async-to-generator installed.

The relevant part of my package.json looks like:

"scripts": {
  "test": "jest",
  "build": "webpack --mode=production",
  "dev": "webpack --mode=development"
},
"jest": {
  "transform": {
    "^.+\\.jsx?$": "babel-jest"
  }
},
"dependencies": {
  "@babel/core": "^7.1.2",
  "@babel/plugin-transform-arrow-functions": "^7.0.0",
  "@babel/plugin-transform-async-to-generator": "^7.1.0",
  "@babel/plugin-transform-modules-commonjs": "^7.1.0",
  "@babel/plugin-transform-runtime": "^7.1.0",
  "@babel/polyfill": "^7.0.0",
  "@babel/preset-env": "^7.1.0",
  "babel-loader": "^8.0.4",
  "clean-webpack-plugin": "^0.1.19",
  "copy-webpack-plugin": "^4.5.2",
  "webpack": "^4.20.2",
  "webpack-cli": "^3.1.2"
},
"devDependencies": {
  "ajv": "^6.5.4",
  "babel-jest": "^23.6.0",
  "eslint": "^5.8.0",
  "jest": "^23.6.0",
  "jsdom": "^13.0.0",
}

My .babelrc is very simple:

{
    "presets": [
        [
            "@babel/preset-env",
            {
                "targets": {
                    "ie": "11"
                },
                "useBuiltIns": "entry"
            }
        ]
    ],
    "plugins": [
        "@babel/transform-async-to-generator",
        "@babel/transform-arrow-functions",
        "@babel/transform-modules-commonjs"
    ],
    "env": {
        "development": {},
        "test": {},
        "production": {}
    }
}

Likewise jest.config.js which is straight out of jest --init :

module.exports = {
    clearMocks: true,
    coverageDirectory: "coverage",
    testEnvironment: "jsdom"
};

Any ideas on what might be going wrong?

Answer 1

Try running npm install --save-dev babel-jest babel-core@^7.0.0-bridge @babel/core , I believe the babel team released a bridge package to aid dependencies that are affected by the v7 upgrade.

See here for more info: https://github.com/facebook/jest/tree/master/packages/babel-jest#usage