Requires Babel "^7.0.0-0", but was loaded with "6.26.3".

[dmurphy5]

🐛 Bug Report

I get the following message when trying to run tests. None of the solutions in the documentation or other issues work.

    Requires Babel "^7.0.0-0", but was loaded with "6.26.3". If you are sure you have a compatible version of @babel/core, it is likely that something in your build process is loading the wrong version. Inspect the stack trace of this error to look for the first entry that doesn't mention "@babel/core" or "babel-core" to see what is calling Babel.

      at throwVersionError (node_modules/@babel/plugin-proposal-class-properties/node_modules/@babel/helper-plugin-utils/lib/index.js:65:11)
      at Object.assertVersion (node_modules/@babel/plugin-proposal-class-properties/node_modules/@babel/helper-plugin-utils/lib/index.js:13:11)
      at _default (node_modules/@babel/plugin-proposal-class-properties/lib/index.js:81:7)
      at node_modules/@babel/plugin-proposal-class-properties/node_modules/@babel/helper-plugin-utils/lib/index.js:19:12
          at Array.map (<anonymous>)

To Reproduce

Relevant package.json dependencies/config

{
   "devDependencies": {
        "@babel/core": "^7.0.0",
        "@babel/plugin-proposal-class-properties": "^7.0.0",
        "@babel/plugin-proposal-decorators": "^7.0.0",
        "@babel/plugin-proposal-object-rest-spread": "^7.0.0",
        "@babel/plugin-syntax-dynamic-import": "^7.0.0",
        "@babel/preset-env": "^7.0.0",
        "@babel/preset-react": "^7.0.0",
        "@babel/register": "^7.0.0",
        "babel-core": "^7.0.0-bridge.0",
        "babel-jest": "^23.4.2",
        "babel-loader": "^8.0.0",
        "jest": "^23.5.0",
        "jest-environment-jsdom": "^23.4.0",
        "jest-junit": "^3.6.0",
        "jest-transform-graphql": "^2.1.0",
        "regenerator-runtime": "^0.12.1"
    },
   "jest": {
        "coveragePathIgnorePatterns": [
            "node_modules",
            "/*.graphql"
        ],
        "transform": {
            "\\.(gql|graphql)$": "jest-transform-graphql",
            "^.+\\.js$": "babel-jest"
        },
        "setupFiles": [
            "<rootDir>/src/jestSetup.js"
        ],
        "snapshotSerializers": [
            "enzyme-to-json/serializer"
        ],
        "testResultsProcessor": "jest-junit"
    }
}

.babelrc

{
    "presets": ["@babel/preset-react"],
    "plugins": [
        "@babel/plugin-proposal-class-properties",
        "@babel/plugin-proposal-object-rest-spread",
        "@babel/plugin-syntax-dynamic-import",
        ["@babel/plugin-proposal-decorators", { "legacy": true }]
    ],
    "env": {
        "test": {
            "presets": ["@babel/preset-env", "@babel/preset-react"]
        }
    }
}

jestSetup.js

import 'regenerator-runtime';
import Enzyme from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';

Enzyme.configure({ adapter: new Adapter() });

Expected behavior

Jest runs correctly

Link to repl or repo (highly encouraged)

Please provide either a repl.it demo or a minimal repository on GitHub.

Issues without a reproduction link are likely to stall.

Run npx envinfo --preset jest

Throws the follwing error

(node:792) UnhandledPromiseRejectionWarning: TypeError: Cannot read property '1' of null

[davidcalhoun]

Strange. I got the exact same error due to me removing babel-core when I updated to Babel 7. I re-added it alongside @babel/core and that fixed it, although I see you're already doing that above:

  "devDependencies": {
    "@babel/core": "^7.0.0",
    "babel-core": "7.0.0-bridge.0"
  }

Are you using package-lock.json? Maybe try deleting it and also remove node_modules, then reinstall? I wonder if there's something lingering from before you upgraded to Babel 7?

[jorgegonzalez]

Running yarn why babel-core points to jest-runtime as the culprit:

[SimenB]

I think this should work, your config looks correct...

Mind setting up a repo showing the error?

[herodrigues]

@jorgegonzalez same here in the project I'm working on

Since I've updated to babel 8 (@babel/core), all tests are breaking.

 FAIL  test/spec/utils.test.js
  ● 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

    Details:

    /home/herinson/.../test/jest.setup.js:1
    ({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import { configure } from 'enzyme';
                                                                                                    ^

    SyntaxError: Unexpected token {

      at ScriptTransformer._transformAndBuildScript (node_modules/jest-runtime/build/script_transformer.js:403:17)

And if I run npm ls babel-core, it shows that jest-runtime depends on babel-core@6.26.3

└─┬ jest@23.5.0
  └─┬ jest-cli@23.5.0
    ├─┬ jest-config@23.5.0
    │ └─┬ babel-core@6.26.3 
    │   └─┬ babel-register@6.26.0
    │     └── babel-core@6.26.3  deduped
    └─┬ jest-runtime@23.5.0
      └── babel-core@6.26.3  deduped

[matthamil]

I was able to get rid of this error by copying node_modules/babel-core into node_modules/jest-config/node_modules overriding the installed babel-core that jest-config installs as its dependency. If you are hitting this error, can you check node_modules/jest-config/node_modules/babel-core and see what version it installed? Compare this with your node_modules/babel-core directory. If your project's babel-core is at 7.0.0-bridge.0, it should look much different from the one in the node_modules/jest-config/node_modules directory.

I did a simple test a minute ago to see if updating jest-config's dep version fixes the issue, and it looks like it does:

cp -r node_modules/babel-core node_modules/jest-config/node_modules

This will copy your 7.0.0 version into the jest-config's dependencies. Run your tests again. This worked for me locally, but I am curious if this works for anyone else. If it does, then my PR #6926 may be a proper resolution for this?

⚠️ NOTE: Copying your node_modules/babel-core directory into node_modules/jest-config/node_modules is not a permanent solution. As soon as you need to reinstall dependencies from scratch again (e.g. for CI), this won't work.

[dmurphy5]

@matthamil That did it. Thanks!

[herodrigues]

@matteofigus that won't work for babel 8 as all babel modules for this version are installed at node_modules/@babel

[g-plane]

My personal temporary solution is adding a postinstall npm script: rimraf node_modules/jest-runtime/node_modules/babel-core node_modules/jest-config/node_modules/babel-core

Note: I am using Yarn.

[baldurh]

A solution for Yarn is to add a resolutions field to package.json like so:

"resolutions": {
  "babel-core": "7.0.0-bridge.0"
}

And then run yarn to update the dependency resolutions

[matthamil]

@herodrigues good point, I updated the PR to reflect the namespaced @babel/core: https://github.com/facebook/jest/pull/6926/files#diff-42f440414578ffb55a0c454ba79a0d5b

[jaywcjlove]

This will be a good solution

sudo npm install babel-core@7.0.0-bridge.0 --save-dev

Run your tests again. This worked for me locally