Can't use this configuration with Jest

[davegomez]

I've been trying to use this Nextjs config to create the github page for my library and also I'm using Jest as a test runner but I have found that if I change my .babelrc file to use it as a JavaScript file instead of JSON it seems Jest doesn't recognize the file and can't use Babel for my tests.

The Jest config I need is as simple as this:

{
  "presets": [
    "env",
    "react"
  ]
}

And the config I mage to use with this Nextjs example is this:

const env = require('./env-config')

module.exports = {
  presets: ['env', 'react', 'next/babel'],
  plugins: [['transform-define', env]],
}

Any idea how can I keep the JSON .babelrc and use your example at the same time or is it possible to use a babelrc.js file with Jest? I haven't found a way to do it 😔

[timneutkens]

I believe it'd work if you install babel-core bridge yarn add babel-core@7.0.0-bridge.0 --dev

What this does is proxy babel-core to @babel/core.

[davegomez]

It didn't work @timneutkens. I'm getting the same error as before:

  ● Test suite failed to run

    Jest encountered an unexpected token

    This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

    By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

    Here's what you can do:
     • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
     • If you need a custom transformation specify a "transform" option in your config.
     • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

    You'll find more details and examples of these config options in the docs:
    https://jestjs.io/docs/en/configuration.html

I'm already using babel 7, and tried running everything with Babel 6 too but it didn't work either.

This is the repo in case you wanna try it https://github.com/davegomez/silky-react-table