Eslint jest/globals environment key unknown

Question

I have a custom eslint-config that has several plugins for various packages, including jest. I have the main set to an index which just extends other files.

Long story I have a jest config file. That looks like.

module.exports = {
    plugins: ['jest'],
    rules: {
        'jest/no-disabled-tests': 'warn',
        'jest/no-focused-tests': 'error',
        'jest/no-identical-title': 'error',
        'jest/valid-expect': 'error',
        'jest/no-alias-methods': 'off',
        'jest/no-jest-import': 'error',
        'jest/no-large-snapshots': ['warn', {maxSize: 300}],
        'jest/no-test-prefixes': 'error',
        'jest/prefer-to-contain': 'warn',
        'jest/prefer-to-have-length': 'warn',
        'jest/valid-describe': 'error',
        'jest/valid-expect-in-promise': 'error',
        'jest/consistent-test-it': 'off',
        'jest/lowercase-name': 'off',
        'jest/no-hooks': 'off',
        'jest/no-jasmine-globals': 'off',
        'jest/no-test-callback': 'off',
        'jest/prefer-expect-assertions': 'off',
        'jest/prefer-to-be-null': 'off',
        'jest/prefer-to-be-undefined': 'off',
        'jest/require-tothrow-message': 'off',
        'jest/expect-expect': 'off',
        'jest/no-test-return-statement': 'off',
        'jest/prefer-inline-snapshots': 'off',
        'jest/prefer-strict-equal': 'off',
        'jest/prefer-spy-on': 'off',
        'jest/prefer-todo': 'warn',
        'jest/prefer-called-with': 'error',
        'jest/no-truthy-falsy': 'off',
        'jest/no-empty-title': 'error',
        'jest/no-mocks-import': 'error',
        'jest/no-commented-out-tests': 'warn',
    },
    env: {
        'jest/globals': true,
    },
}

When running a lint task I keep getting the error Environment key "jest/globals" is unknown. I've traced the config-validator as far as I can understand it but nothing jumps out. There are no open/closed issues on the eslint-plugin-jest board about this and I can't find anyone else with this same error.

Also for an added bonus I also have cypress plugin also installed which itself has a environment option cypress/globals: true which also throws the same error.

Has anyone encountered this and know why (in the last month or so) this has started happening. Note: I have had this config for some time now and this just started happening.

Edit: I just downgraded to eslint^6.1.0 and this issue is no longer present. Something between 6.1.0 and 6.4.0 is causing this issue.

Answer 1

Putting it in extends solved this issue for me.

...
"extends": ["eslint:recommended", "plugin:jest/recommended"],
...

Answer 2

Follow this guide:

https://www.npmjs.com/package/eslint-plugin-jest

Basics is: npm i --save-dev eslint-plugin-jest

Add this to your .eslintrc file:

"plugins": ["jest"]

Then your env property "jest/globals": true should work.

Answer 3

I have also faced this issue and solved by following steps:

1. Update package.json to remove react-app/jest in eslintConfig:

"eslintConfig": {
    "extends": [
      "react-app",
      "react-app/jest" // REMOVE THIS
    ]
  }

2. Run npm install and check again if it works.

Answer 4

After multipy attemts to get rid of this annoing message in my CRA-based react project, I landed with follow development dependecies:

"eslintConfig": {
  "rules": {
    "semi": [
      "error",
      "never"
    ],
    "no-extra-semi": "error",
    "react/jsx-uses-react": 0,
    "react/react-in-jsx-scope": 0
  },
  "env": {
    "browser": true,
    "es2021": true,
    "jest/globals": true
  },
  "extends": [
    "react-app",
    "react-app/jest"
  ]
},
"devDependencies": {
  "@babel/core": "^7.16.5",
  "@babel/plugin-syntax-flow": "^7.16.5",
  "@babel/plugin-transform-react-jsx": "^7.16.5",
  "@babel/preset-env": "^7.16.5",
  "@iconify-icons/eva": "^1.1.0",
  "@iconify/react": "^3.1.0",
  "@testing-library/dom": "^8.11.1",
  "@testing-library/jest-dom": "^5.16.1",
  "@testing-library/react": "^12.1.2",
  "@testing-library/user-event": "^13.5.0",
  "@types/jest": "^27.0.3",
  "@types/node": "^17.0.0",
  "@types/react": "^17.0.37",
  "@types/react-dom": "^17.0.11",
  "@typescript-eslint/eslint-plugin": "^5.7.0",
  "@typescript-eslint/parser": "^5.7.0",
  "autoprefixer": "^10.4.0",
  "babel-eslint": "^10.1.0",
  "cross-env": "^7.0.3",
  "eslint": "^8.5.0",
  "eslint-config-react-app": "^7.0.0",
  "eslint-plugin-flowtype": "^8.0.3",
  "eslint-plugin-import": "^2.25.3",
  "eslint-plugin-jsx-a11y": "^6.5.1",
  "eslint-plugin-react": "^7.27.1",
  "eslint-plugin-react-hooks": "^4.3.0",
  "node-sass": "^7.0.0",
  "postcss": "^8.4.5",
  "typescript": "^4.5.4"
}

Critical was adding yarn add --dev eslint-config-react-app. In opposit to other solutions it does not require removing react-app/jest plugin from the eslint config section. Hope this helps others to bypass the issue and save time :)

Answer 5

Order of the plugins matter in eslintrc.js.

For me placing 'jest' as the first element in the array of plugins worked

plugins: ['jest', 'react', '@typescript-eslint']

Answer 6

In my same error case, one package's peerDependencies "eslint" version is different with main project's eslint package.

// sub-package
"peerDependencies": {
   "eslint": "7.x"
},
// main package
"eslint": "^8.0.0",  // => Solve with ^7.0.0 

Answer 7

Adding one extra thing that fixed this issue for me:

Node 12/npm 6 was throwing: Environment key “jest/globals” is unknown

Tried with all the suggestions in the answers of this thread and no one worked, it got fixed when I ran the exact same configuration using node 16/npm 8.

Answer 8

If you're getting this error when using create react app v5

It's likely because the project is not using the updated version of ESLint (version 8). react-scripts @ v5 change log documents the breaking change (https://github.com/facebook/create-react-app/blob/main/CHANGELOG.md#highlights) so the reason removing "react-app/jest" works is because the configuration schema in react-app/jest broke version 8 of ESlint.

To fix the issue:

• Remove ESLint and its associated plugins and run the getting started flow (https://eslint.org/docs/user-guide/getting-started).
• Go to the jest ESLint documentation (https://github.com/jest-community/eslint-plugin-jest) and follow their configuration steps.