Next + Jest does not support common .babelrc

I recently tried to define special presets in .babelrc only for test environment in with-jest example. When importing a file for testing that uses React and/or StyledJSX and that does not manually import React and/or StyledJSX, the test will fail with following error message:

SyntaxError: Unexpected token import

This is because the automatically added imports of React/StyledJSX are always es2015 style module imports.

• I have searched the issues of this repository and believe that this is not a duplicate.

Expected Behavior

A simple .babelrc that only defines a special test env should be possible. In my opinion it should be possible to use the following .babelrc:

{
  "presets": "next/babel",
  "env": {
    "test": {
      "presets": [
        "env",
        "next/babel"
      ]
    }
  }
}

I played with this issue on a separate branch. Currently you could work around this issue by importing React & StyledJSX manually:

import React from 'react'
import _JSXStyle from 'styled-jsx/style'

Current Behavior

Either you define development, production and test envs in .babelrc whereas development and production or you manually import React / StyledJSX. Otherwise tests with JEST will fail.

Steps to Reproduce (for bugs)

1. Goto examples/with-jest
2. Simplify your .babelrc as proposed
3. Run $ npm run test

[pex]

Thank you for your quick response @arunoda . Unfortunately those suggestions won’t fix the issue. I added your suggestions to .babelrc in https://github.com/pex/next.js/commit/220d7a8e30cb244524f942434197725a0a5aa75d and tests fail with the same message they did before.

Another note on this:

• I am not sure about what the impact of switching order of next/babel and env is;
• Writing ["env", { "modules": "commonjs" }] is obsolete, though. Since this is default in env: https://babeljs.io/docs/plugins/preset-env/#optionsmodules

[arunoda]

@sergiodxa I think the issue is, ["env", { "modules": "commonjs" }] should run before next/babel in test.

If you set a default one. It’ll run always at first.