New Cypress 10 global TypeScript type conflicts with Jest expect

[karlhorky]

Current behavior

The following new global TypeScript type for expect in node_modules/cypress/types/cypress-expect.d.ts causes conflicts with Jest expect types, if a project has both Jest and Cypress:

cypress/cli/types/cypress-expect.d.ts

Line 2 in a0a64cc

declare const expect: Chai.ExpectStatic

Errors:

Property 'toBe' does not exist on type 'Assertion'.

When looking through the docs, there is a guide here:

Cypress Types Conflict with Jest

However, this guide is based on the fact that Cypress types were not global before (but they are now).

Desired behavior

No response

Test code to reproduce

Jest test code (filename __tests__/colors.test.ts):

import { findWhiteContrastingColor } from '../colors';

test('findWhiteContrastingColor finds colors contrasting with white', () => {
  expect(findWhiteContrastingColor(['#ffffff', '#000000', '#e1e1e1'])).toBe(
    '#000000',
  );
});

Cypress Version

10.0.1

Other

No response

[karlhorky]

Workarounds

Workaround 1

Use patch-package to patch node_modules/cypress/types/cypress-expect.d.ts with the following content (comment out the global expect type):

// Cypress adds chai expect and assert to global
// declare const expect: Chai.ExpectStatic
declare const assert: Chai.AssertStatic

Then add back the expect variable at the top of all of your test files:

declare const expect: Chai.ExpectStatic;

Workaround 2

Use local-cypress and import expect (more info):

import { expect } from 'local-cypress';

[Yberion]

Hello,

We also have this problem with Karma/Jasmine on Angular.

Do you have any informations on if and when you will fix that issue ?

The workarounds aren't clear enough to be honest, and they are "workaround" anyway which isn't really good.
All Angular projects updating to Cypress 10 will have a clashing problem with describe, it, expect, ...

It's kinda "critical" I think 😄

Have a good day!

[ZachJW34]

@karlhorky thanks for posting, looks like you're not the only one having issues with Cypress + Jest type collisions.

I was able to reproduce this with the repos linked @karlhorky @mrdrogdrog @wKovacs64. When I checked out the dep update to v10, all of the Jest tests started complaining.

We didn't change our globals very much for v10. For all the cases I reproduced, it was fixed by adding ./cypress.config.ts to the tsconfig.exclude property. Since the cypress.config.ts is being included in the type checking, it is loading the cypress types which is polluting your jest tests.

[Yberion]

Hello @ZachJW34,

Edit: removed the old message, I misread your answer, it indeed work, thank you!

[karlhorky]

adding ./cypress.config.ts to the tsconfig.exclude property

This worked for me, thanks @ZachJW34 !

[yuriy1715]

adding ./cypress.config.ts to the tsconfig.exclude property
Thank you @ZachJW34 it helps for me too

[karlhorky]

@marktnoonan @ZachJW34 @mjhenkes should we leave this one open so that the documentation page mentioned in the issue description is updated?

[kuantayevs]

@karlhorky thanks for posting, looks like you're not the only one having issues with Cypress + Jest type collisions.

I was able to reproduce this with the repos linked @karlhorky @mrdrogdrog @wKovacs64. When I checked out the dep update to v10, all of the Jest tests started complaining.

We didn't change our globals very much for v10. For all the cases I reproduced, it was fixed by adding ./cypress.config.ts to the tsconfig.exclude property. Since the cypress.config.ts is being included in the type checking, it is loading the cypress types which is polluting your jest tests.

Thank you for sharing this @ZachJW34 , but this seems does not work for me, maybe you could help me. I still see errors which is listed at very first messge

structure:
cypress - cypress tests
- tsconfig.json has "exclude": ["../cypress.config.ts"]
src - unit test using jest
cypress.config.ts

tsconfig.json

    "compilerOptions": {
        "baseUrl": ".",
        "esModuleInterop": true,
        "lib": ["dom", "esnext"],
        "noEmit": true,
        "skipLibCheck": true,
        "strict": true
    },
    "include": ["../../node_modules/cypress", "**/*"],
    "exclude": ["../cypress.config.ts"]
}```

[arelra]

@karlhorky @ZachJW34 Thanks for all your input here

We had the same issue blocking our upgrade to v10.

Adding cypress.config.[js|ts] to tsconfig.json's exclude property worked for us too.

I would also like to echo that this issue be elevated to the v10 migration guide or made much clearer in the documentation please. It is very difficult to diagnose and remedy without any pointers.

Thanks

[marktnoonan]

I've created cypress-io/cypress-documentation#4559 against the docs repo so that we can document the solution there. Thanks everybody for reporting and providing examples, and @ZachJW34 for pointing out the right step to take.

Good point @arelra about maybe mentioning this in the Migration Guide and as part of migration itself, we will consider both.

Going to keep this issue open a little longer since it does seem like we somebody for whom exclude is not working yet. @kuantayevs am I reading your structure correctly, in that your tsconfig.json is nested inside your cypress folder?

[SchroederSteffen]

Note: I also had to add "files": ["../cypress.config.ts"], to the cypress/tsconfig.json after adding "exclude": ["cypress.config.ts"] to the tsconfig.json.

[karlhorky]

tsconfig.json has "exclude": ["../cypress.config.ts"]

@kuantayevs what worked for me in my monorepo structure was to add the exclude to the base tsconfig.json in the root of the project:

{
  "exclude": [
    "packages/fusion.upleveled.io/cypress.config.ts",
  ]
}

Adding to the "exclude" array in a tsconfig.json deeper in one of the folders did NOT work.

[karlhorky]

Note: I also had to add "files": ["../cypress.config.ts"], to the cypress/tsconfig.json after adding "exclude": ["cypress.config.ts"] to the tsconfig.json.

@SchroederSteffen why did you need to do this? (eg. what were the details of what was happening without this change?)

I didn't need to do this, but maybe I and others would want to for some reason...

[SchroederSteffen]

Note: I also had to add "files": ["../cypress.config.ts"], to the cypress/tsconfig.json after adding "exclude": ["cypress.config.ts"] to the tsconfig.json.

@SchroederSteffen why did you need to do this? (eg. what were the details of what was happening without this change?)

I didn't need to do this, but maybe I and others would want to for some reason...

Yes, sorry for not clarifying! 🤦‍♂️
It was needed, because otherwise the typescript-eslint plugin would raise the following error:

C:\<project-directory>\cypress.config.ts
  0:0  error  Parsing error: "parserOptions.project" has been set for @typescript-eslint/parser.
The file does not match your project config: cypress.config.ts.
The file must be included in at least one of the projects provided

Note: Our ESLint config selects files as follows:

  overrides: [
    {
      files: ['*.ts'],
      parserOptions: {
        project: ['tsconfig.json'],
      },
      extends: [
        'plugin:@typescript-eslint/recommended',
        'plugin:@typescript-eslint/recommended-requiring-type-checking',
        [...],
      ],
      [...],
      overrides: [
        {
          files: ['cypress/**/*.ts'],
          parserOptions: {
            project: ['cypress/tsconfig.json'],
          },
          extends: ['plugin:cypress/recommended'],
        },
      ]
    }
  ]

[karlhorky]

Oh fancy, didn't know that about the overrides config! 😯 I have been creating .eslintrc.js files in all of the sub-directories that I need to configure differently and then adding lines to .eslintignore for those which don't match the include and exclude in my tsconfig.json. But this is a downside because it ignores any lint errors in cypress.config.ts ...

[uKiJo]

For me only this config worked. All my cypress tests are in *.cy.jsx files, so I explicitly excluded them too

  "exclude": [
    "node_modules",
    "cypress",
    "cypress.config.ts",
    "**/*.cy.jsx"
  ],

that worked very well for me, the "cypress" which solved the problem with me!

[felixcatto]

For me that worked well. Jest and Cypress now have correct types.

tsconfig.json

  "include": ["**/*.ts", "**/*.tsx"],
  "exclude": ["node_modules", "cypress.config.ts", "cypress"]

cypress/tsconfig.json

  "compilerOptions": {
    ...
    "types": ["cypress"]
  },
  "include": ["../node_modules/cypress", "./**/*.ts"]

[mnogueron]

If you are using eslint as well, don't forget to add an override to redefine the parserOptions.project, otherwise eslint will complain that no project file is associated with the cypress specs:

{
	...
	"overrides": [
		{
			"files": ["cypress/**/*.ts", "cypress.config.ts"],
			"parserOptions": {
				"project": "./cypress/tsconfig.json"
			},
			...
		},
		...
	],
	"parser": "@typescript-eslint/parser",
	"parserOptions": {
		"project": "./tsconfig.json",
		...
	},
}

[mmcgee-aya]

This is still an issue with a brand new install of Angular and cypress as of 7/12/2023.. Is there an official fix/documentation

"dependencies": {
"@angular/animations": "^16.1.0",
"@angular/common": "^16.1.0",
"@angular/compiler": "^16.1.0",
"@angular/core": "^16.1.0",
"@angular/forms": "^16.1.0",
"@angular/platform-browser": "^16.1.0",
"@angular/platform-browser-dynamic": "^16.1.0",
"@angular/router": "^16.1.0",
"rxjs": "~7.8.0",
"tslib": "^2.3.0",
"zone.js": "~0.13.0"
},
"devDependencies": {
"@angular-devkit/build-angular": "^16.1.1",
"@angular/cli": "~16.1.1",
"@angular/compiler-cli": "^16.1.0",
"@types/jasmine": "~4.3.0",
"cypress": "^12.17.1",
"jasmine-core": "~4.6.0",
"karma": "~6.4.0",
"karma-chrome-launcher": "~3.2.0",
"karma-coverage": "~2.2.0",
"karma-jasmine": "~5.1.0",
"karma-jasmine-html-reporter": "~2.1.0",
"typescript": "~5.1.3"
}

[cniemann88]

Also still an issue for me...Angular with jest tests

Adding these lines to the tsconfig.json file
"exclude": [ "./cypress.config.ts", "node_modules", "**/*.cy.ts" ], "include": ["src/**/*.ts"]
works only for the cypress tests inside the cypress folder...component tests that are co-located with jest tests are throwing errors like below:

adding
///<reference types="cypress/jest"/>

only partially works, and is not a sustainable solution for an existing system with hundreds of jest spec files.

[lmiller1990]

Other than adding /// reference on a file by file basis, I am unsure if there is any real fix other than test runners exporting their own expect as module. This is one of the many reasons global variables are not good, it's hard to know who defines them and how to type them.

I think Cypress should have a frontend module bundle that does

import { expect, cy, Cypress, describe, it } from 'cypress'

as suggested above in this post: #22059 (comment). It looks like there is already a package that partially implements this: https://github.com/bahmutov/local-cypress#readme

Even if these are dynamically injected at runtime, the exports should just be type safety wrappers and no-ops, in the same way `import { defineConfig } from 'cypress' is a no-op at runtime - it just adds type safety.

I am unsure on the complexity of this or if we are looking to implement this soon. Is someone interested on working on this? If so, I can propose this internally to our product team to get requirements (if we decide to prioritize it).

[kleinfreund]

@lmiller1990 Regarding your last comment, maybe https://www.npmjs.com/package/@jest/globals can be a point for inspiration. I’m using this package to avoid globally typing "Jest globals" and it works very well.

[maccurt]

This is very frustrating. I think I don't want to install cypress into my Angular project, but I want to do Component testing. Very hard to bring this to my team, when it break all the asserts for our unit test. Let us make sure also our custom commands still work with this implementation, etc. I notice I get one thing working, then it breaks something else. WE CAN NOT ACCEPT INSTALLING THIS package if it breaks our unit test asserts. I AM VERY SUPRISED this was allowed to get past QA at cypress. I give a lot of grace, but this is breaking a brand new angular project with YOUR INSTRUCTIONS. I guess I am frustrated because I really want to use component testing, but I think I will separate my MY CYPRESS project from my Angular project so they do not collide AND NOT DO COMPONENT TESTING. All I ask is you follow your own instructions and see it breaks. Just do a simple NG new my-project and then install cypress, RIGHT OUT THE BOX IT IS BROKE..

[etsraphael]

Please does somebody have a fix about this one? The latest version brought back this issue.

[lmiller1990]

The problem is multiple tools declaring matching globals. This issue could be opened in Jest and be just as relevant.

It looks like Jest has a module API that exposes these: https://jestjs.io/docs/api

import { expect } from '@globals/jest'

There is also something similar via local-cypress: https://www.npmjs.com/package/local-cypress

Surely this combination could let you both

import { expect } from '@jest/globals'
import { expect } from 'local-cypress'

Or you can use

/// <reference types= "cypress" />

For Cypress files. These are the workarounds suggested above, too: #22059 (comment). Have you tried these, @etsraphael?

@maccurt can you try these? There is no magic way to make it work, you'll need to make sure each spec file knows which test runner / tool it's associated with. It doesn't look like you've tried that yet. Give one of these a try, it should fix your issue.

As an aside, I don't know why any framework still uses global variables. I have run into this too, but the reality is if there are multiple types assigned to the same variable (eg expect) there isn't a good way for the IDE to "know" which one to use reliability without imports or references.

I'm not sure if there's any edge cases with local-cypress - if not, I'd love to see this in core, but I suspect there are some issues that would need to be ironed out.

[maccurt]

@lmiller1990 I will give that a try

[jennifer-shehane]

Please see our docs for recommendations on how to avoid clashing. Docs were updated in this PR: cypress-io/cypress-documentation#5514

We investigated ways to automatically avoid this in our product, but didn't come to a clear solution unfortunately.

[tar-aldev]

It's still not working for nrwl/nx monorepo.
If you exlucde jest tests in tsconfig.json and then try to import any other lib defined in tsconfig.base.json paths, it won't work.
You can see details here
nrwl/nx#19569

and repo here
https://github.com/tar-aldev/nrwl-nx-cypress-component-testing-issues/tree/with-suggested-cypresss-docs-fix