Not implemented: window.computedStyle(elt, pseudoElt)

I am getting the following error for the following test with jest-axe:

Am I missing something?

Error: Not implemented: window.computedStyle(elt, pseudoElt)

test/setup.ts:

import '@testing-library/jest-dom/extend-expect'
import 'jest-axe/extend-expect'

file.spec.tsx:

const a11y = await axe(container)
expect(a11y).toHaveNoViolations()

jest.config.js

{
  displayName: 'web:test',
  preset: 'ts-jest',
  testEnvironment: 'jsdom',
  testMatch: ['**/__tests__/**/+(*.)+(spec|test).+(js|ts)?(x)'],
  moduleNameMapper: {
    '^~/(.*)$': '<rootDir>/src/$1',
    '^test/(.*)$': '<rootDir>/test/$1'
  },
  setupFilesAfterEnv: ['<rootDir>/test/setup.ts'],
  globals: {
    'ts-jest': {
      tsconfig: {
        jsx: 'react'
      }
    }
  }
}

deps:

“jest”: “^26.6.3”, “jest-axe”: “^4.1.0”, “react-test-renderer”: “^17.0.1”, “ts-jest”: “^26.4.4”, “typescript”: “^4.1.2”

Issue Analytics

State:
Created 3 years ago
Reactions:4
Comments:7 (3 by maintainers)

Top GitHub Comments

53reactions

GriffinSaucecommented, Jan 12, 2021

This workaround appears to break functionality in jest-axe, my simple check with a missing <select> label will return green when window.getComputedStyle is just replaced with a noop.

As an alternative I’ve only stripped the second (unsupported) parameter and this at least keeps that test functional:

const { getComputedStyle } = window;
window.getComputedStyle = (elt) => getComputedStyle(elt);

You can add this in a testSetup file to apply to all tests instead of using a local beforeAll. That said: I expect that this will still introduce inaccuracy in tests, that second param must be there for a reason.

This issue in the jest-dom repo got a bit heated but the conclusion seems to be that it should not be fixed be fixed there… so does this belong with React Testing Library?

It appears to be fixed in dom-testing-library and subsequently react-testing-library but I’m still getting it in newer versions of RTL.

So my conclusion is: I don’t know where to go with this 😅

9reactions

nickytonlinecommented, Nov 26, 2020

I am experiencing this as well. For now, I’ve added the following to my tests where this fails. It’s a noop patch for now.

Happy to dig into this @nickcolley if you’re super busy.

describe('Some tests', () => {
  beforeAll(() => {
    // JSDom does not implement this and an error was being
    // thrown from jest-axe because of it.
    window.getComputedStyle = () => {};
  });

  // my tests ...
})

Also, here’s the full stack trace of this error:

  console.error
    Error: Not implemented: window.computedStyle(elt, pseudoElt)
        at module.exports (/Users/johndoe/dev/forem/node_modules/jsdom/lib/jsdom/browser/not-implemented.js:9:17)
        at Window.getComputedStyle (/Users/johndoe/dev/forem/node_modules/jsdom/lib/jsdom/browser/Window.js:657:7)
        at hasPsuedoElement2 (/Users/johndoe/dev/forem/node_modules/axe-core/axe.js:16285:26)
        at /Users/johndoe/dev/forem/node_modules/axe-core/axe.js:2253:30
        at Object.colorContrastEvaluate (/Users/johndoe/dev/forem/node_modules/axe-core/axe.js:16331:13)
        at Check.Object.<anonymous>.Check.run (/Users/johndoe/dev/forem/node_modules/axe-core/axe.js:18562:34)
        at /Users/johndoe/dev/forem/node_modules/axe-core/axe.js:18698:18
        at pop (/Users/johndoe/dev/forem/node_modules/axe-core/axe.js:6198:18)
        at Object.defer (/Users/johndoe/dev/forem/node_modules/axe-core/axe.js:6220:11)
        at /Users/johndoe/dev/forem/node_modules/axe-core/axe.js:18697:20 undefined

      at VirtualConsole.<anonymous> (node_modules/jsdom/lib/jsdom/virtual-console.js:29:45)
      at module.exports (node_modules/jsdom/lib/jsdom/browser/not-implemented.js:12:26)
      at Window.getComputedStyle (node_modules/jsdom/lib/jsdom/browser/Window.js:657:7)
      at hasPsuedoElement2 (node_modules/axe-core/axe.js:16285:26)
      at node_modules/axe-core/axe.js:2253:30
      at Object.colorContrastEvaluate (node_modules/axe-core/axe.js:16331:13)

It seems that this might be a jsdom issue though and not a jest-axe issue.

Top Results From Across the Web

Not implemented: window.computedStyle(elt, pseudoElt) #147

I am getting the following error for the following test with jest-axe: Am I missing something? Error: Not implemented: window.

Not implemeted window errors in react-testing-library

The tests are all passing but I get a large amount of errors from jsdom logged to the console: Error: Not implemented: window.computedStyle(elt, ......

Not implemented: window.computedStyle(elt, pseudoElt)

Coming soon: A brand new website interface for an even better experience!

jest: debugging 'not implemented' errors - code-comments

I recently added a feature to an app that scrolls the user to the top of page on navigation. Unfortunately, this started spewing...

Window.getComputedStyle() - Web APIs | MDN

The Window.getComputedStyle() method returns an object containing the values of all CSS properties of an element, after applying active ...