react-testing-library

Simple and complete React DOM testing utilities that encourage good testing practices.

[**Read The Docs**](https://testing-library.com/react) | [Edit the docs](https://github.com/alexkrolick/testing-library-docs)

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TestingJavaScript.com Learn the smart, efficient way to test any JavaScript application.

## Table of Contents - [The problem](#the-problem) - [This solution](#this-solution) - [Example](#example) - [Installation](#installation) - [Examples](#examples) - [Other Solutions](#other-solutions) - [Guiding Principles](#guiding-principles) - [Contributors](#contributors) - [Issues](#issues) - [🐛 Bugs](#-bugs) - [💡 Feature Requests](#-feature-requests) - [❓ Questions](#-questions) - [LICENSE](#license) ## The problem You want to write maintainable tests for your React components. As a part of this goal, you want your tests to avoid including implementation details of your components and rather focus on making your tests give you the confidence for which they are intended. As part of this, you want your testbase to be maintainable in the long run so refactors of your components (changes to implementation but not functionality) don't break your tests and slow you and your team down. ## This solution The `react-testing-library` is a very light-weight solution for testing React components. It provides light utility functions on top of `react-dom` and `react-dom/test-utils`, in a way that encourages better testing practices. Its primary guiding principle is: > [The more your tests resemble the way your software is used, the more > confidence they can give you.][guiding-principle] ## Example ```javascript // __tests__/fetch.js import React from 'react' import {render, fireEvent, cleanup, waitForElement} from 'react-testing-library' // this adds custom jest matchers from jest-dom import 'jest-dom/extend-expect' // the mock lives in a __mocks__ directory // to know more about manual mocks, access: https://jestjs.io/docs/en/manual-mocks import axiosMock from 'axios' import Fetch from '../fetch' // see the tests for a full implementation // automatically unmount and cleanup DOM after the test is finished. afterEach(cleanup) test('Fetch makes an API call and displays the greeting when load-greeting is clicked', async () => { // Arrange axiosMock.get.mockResolvedValueOnce({data: {greeting: 'hello there'}}) const url = '/greeting' const {getByText, getByTestId, container, asFragment} = render( , ) // Act fireEvent.click(getByText(/load greeting/i)) // Let's wait until our mocked `get` request promise resolves and // the component calls setState and re-renders. // getByTestId throws an error if it cannot find an element with the given ID // and waitForElement will wait until the callback doesn't throw an error const greetingTextNode = await waitForElement(() => getByTestId('greeting-text'), ) // Assert expect(axiosMock.get).toHaveBeenCalledTimes(1) expect(axiosMock.get).toHaveBeenCalledWith(url) expect(getByTestId('greeting-text')).toHaveTextContent('hello there') expect(getByTestId('ok-button')).toHaveAttribute('disabled') // snapshots work great with regular DOM nodes! expect(container.firstChild).toMatchSnapshot() // you can also use get a `DocumentFragment`, which is useful if you want to compare nodes across render expect(asFragment()).toMatchSnapshot() }) ``` ## Installation This module is distributed via [npm][npm] which is bundled with [node][node] and should be installed as one of your project's `devDependencies`: ``` npm install --save-dev react-testing-library ``` This library has `peerDependencies` listings for `react` and `react-dom`. You may also be interested in installing `jest-dom` so you can use [the custom jest matchers](https://github.com/gnapse/jest-dom#readme). > [**Docs**](https://testing-library.com/docs/react-testing-library/intro) ## Examples > We're in the process of moving examples to the > [docs site](https://testing-library.com/docs/example-codesandbox) You'll find runnable examples of testing with different libraries in [the `examples` directory](https://github.com/kentcdodds/react-testing-library/blob/master/examples). Some included are: - [`react-redux`](https://github.com/kentcdodds/react-testing-library/blob/master/examples/__tests__/react-redux.js) - [`react-router`](https://github.com/kentcdodds/react-testing-library/blob/master/examples/__tests__/react-router.js) - [`react-context`](https://github.com/kentcdodds/react-testing-library/blob/master/examples/__tests__/react-context.js) - [`react-hooks`](https://github.com/kentcdodds/react-testing-library/blob/master/examples/__tests__/react-hooks.js) - Use react-testing-library to test a custom React Hook. You can also find react-testing-library examples at [react-testing-examples.com](https://react-testing-examples.com/jest-rtl/). ## Other Solutions In preparing this project, [I tweeted about it](https://twitter.com/kentcdodds/status/974278185540964352) and [Sune Simonsen](https://github.com/sunesimonsen) [took up the challenge](https://twitter.com/sunesimonsen/status/974784783908818944). We had different ideas of what to include in the library, so I decided to create this one instead. ## Guiding Principles > [The more your tests resemble the way your software is used, the more > confidence they can give you.][guiding-principle] We try to only expose methods and utilities that encourage you to write tests that closely resemble how your react components are used. Utilities are included in this project based on the following guiding principles: 1. If it relates to rendering components, it deals with DOM nodes rather than component instances, nor should it encourage dealing with component instances. 2. It should be generally useful for testing individual React components or full React applications. While this library is focused on `react-dom`, utilities could be included even if they don't directly relate to `react-dom`. 3. Utility implementations and APIs should be simple and flexible. At the end of the day, what we want is for this library to be pretty light-weight, simple, and understandable. ## Contributors Thanks goes to these people ([emoji key][emojis]): | [

_{Kent C. Dodds}](https://kentcdodds.com)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=kentcdodds "Code") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=kentcdodds "Documentation") [🚇](#infra-kentcdodds "Infrastructure (Hosting, Build-Tools, etc)") [⚠️](https://github.com/kentcdodds/react-testing-library/commits?author=kentcdodds "Tests") | [

_{Ryan Castner}](http://audiolion.github.io)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=audiolion "Documentation") | [

_{Daniel Sandiego}](https://www.dnlsandiego.com)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=dnlsandiego "Code") | [

_{Paweł Mikołajczyk}](https://github.com/Miklet)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=Miklet "Code") | [

_{Alejandro Ñáñez Ortiz}](http://co.linkedin.com/in/alejandronanez/)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=alejandronanez "Documentation") | [

_{Matt Parrish}](https://github.com/pbomb)
[🐛](https://github.com/kentcdodds/react-testing-library/issues?q=author%3Apbomb "Bug reports") [💻](https://github.com/kentcdodds/react-testing-library/commits?author=pbomb "Code") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=pbomb "Documentation") [⚠️](https://github.com/kentcdodds/react-testing-library/commits?author=pbomb "Tests") | [

_{Justin Hall}](https://github.com/wKovacs64)
[📦](#platform-wKovacs64 "Packaging/porting to new platform") | | :---: | :---: | :---: | :---: | :---: | :---: | :---: | | [

_{Anto Aravinth}](https://github.com/antoaravinth)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=antoaravinth "Code") [⚠️](https://github.com/kentcdodds/react-testing-library/commits?author=antoaravinth "Tests") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=antoaravinth "Documentation") | [

_{Jonah Moses}](https://github.com/JonahMoses)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=JonahMoses "Documentation") | [

_{Łukasz Gandecki}](http://team.thebrain.pro)
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_{Ivan Babak}](https://sompylasar.github.io)
[🐛](https://github.com/kentcdodds/react-testing-library/issues?q=author%3Asompylasar "Bug reports") [🤔](#ideas-sompylasar "Ideas, Planning, & Feedback") | [

_{Jesse Day}](https://github.com/jday3)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=jday3 "Code") | [

_{Ernesto García}](http://gnapse.github.io)
[💬](#question-gnapse "Answering Questions") [💻](https://github.com/kentcdodds/react-testing-library/commits?author=gnapse "Code") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=gnapse "Documentation") | [

_{Josef Maxx Blake}](http://jomaxx.com)
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_{Michal Baranowski}](https://twitter.com/baranovskim)
[📝](#blog-mbaranovski "Blogposts") [✅](#tutorial-mbaranovski "Tutorials") | [

_{Arthur Puthin}](https://github.com/aputhin)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=aputhin "Documentation") | [

_{Thomas Chia}](https://github.com/thchia)
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_{Thiago Galvani}](http://ilegra.com/)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=thiagopaiva99 "Documentation") | [

_Christian](http://Chriswcs.github.io)
[⚠️](https://github.com/kentcdodds/react-testing-library/commits?author=ChrisWcs "Tests") | [

_{Alex Krolick}](https://alexkrolick.com)
[💬](#question-alexkrolick "Answering Questions") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=alexkrolick "Documentation") [💡](#example-alexkrolick "Examples") [🤔](#ideas-alexkrolick "Ideas, Planning, & Feedback") | [

_{Johann Hubert Sonntagbauer}](https://github.com/johann-sonntagbauer)
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_{Maddi Joyce}](http://www.maddijoyce.com)
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_{Ryan Vice}](http://www.vicesoftware.com)
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_{Ian Wilson}](https://ianwilson.io)
[📝](#blog-iwilsonq "Blogposts") [✅](#tutorial-iwilsonq "Tutorials") | [ Daniel

_Daniel](https://github.com/InExtremaRes)
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_{Giorgio Polvara}](https://twitter.com/Gpx)
[🐛](https://github.com/kentcdodds/react-testing-library/issues?q=author%3AGpx "Bug reports") [🤔](#ideas-Gpx "Ideas, Planning, & Feedback") | [

_{John Gozde}](https://github.com/jgoz)
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_{Sam Horton}](https://twitter.com/SavePointSam)
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_{Richard Kotze (mobile)}](http://www.richardkotze.com)
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_{Brahian E. Soto Mercedes}](https://github.com/sotobuild)
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_{Benoit de La Forest}](https://github.com/bdelaforest)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=bdelaforest "Documentation") | [ Salah

_Salah](https://github.com/thesalah)
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_{Adam Gordon}](http://gordonizer.com)
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_{Matija Marohnić}](https://silvenon.com)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=silvenon "Documentation") | [

_{Justice Mba}](https://github.com/Dajust)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=Dajust "Documentation") | | [

_{Mark Pollmann}](https://markpollmann.com/)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=MarkPollmann "Documentation") | [

_{Ehtesham Kafeel}](https://github.com/ehteshamkafeel)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=ehteshamkafeel "Code") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=ehteshamkafeel "Documentation") | [

_{Julio Pavón}](http://jpavon.com)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=jpavon "Code") | [

_{Duncan L}](http://www.duncanleung.com/)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=duncanleung "Documentation") [💡](#example-duncanleung "Examples") | [

_{Tiago Almeida}](https://www.linkedin.com/in/tyagow/?locale=en_US)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=tyagow "Documentation") | [

_{Robert Smith}](http://rbrtsmith.com/)
[🐛](https://github.com/kentcdodds/react-testing-library/issues?q=author%3Arbrtsmith "Bug reports") | [

_{Zach Green}](https://offbyone.tech)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=zgreen "Documentation") | | [

_dadamssg](https://github.com/dadamssg)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=dadamssg "Documentation") | [

_{Yazan Aabed}](https://www.yaabed.com/)
[📝](#blog-YazanAabeed "Blogposts") | [ Tim

_Tim](https://github.com/timbonicus)
[🐛](https://github.com/kentcdodds/react-testing-library/issues?q=author%3Atimbonicus "Bug reports") [💻](https://github.com/kentcdodds/react-testing-library/commits?author=timbonicus "Code") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=timbonicus "Documentation") [⚠️](https://github.com/kentcdodds/react-testing-library/commits?author=timbonicus "Tests") | [

_{Divyanshu Maithani}](http://divyanshu.xyz)
[✅](#tutorial-divyanshu013 "Tutorials") [📹](#video-divyanshu013 "Videos") | [

_{Deepak Grover}](https://www.linkedin.com/in/metagrover)
[✅](#tutorial-metagrover "Tutorials") [📹](#video-metagrover "Videos") | [

_{Eyal Cohen}](https://github.com/eyalcohen4)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=eyalcohen4 "Documentation") | [

_{Peter Makowski}](https://github.com/petermakowski)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=petermakowski "Documentation") | | [

_{Michiel Nuyts}](https://github.com/Michielnuyts)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=Michielnuyts "Documentation") | [

_{Joe Ng'ethe}](https://github.com/joeynimu)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=joeynimu "Code") [📖](https://github.com/kentcdodds/react-testing-library/commits?author=joeynimu "Documentation") | [ Kate

_Kate](https://github.com/Enikol)
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_Sean](http://www.seanrparker.com)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=SeanRParker "Documentation") | [

_{James Long}](http://jlongster.com)
[🤔](#ideas-jlongster "Ideas, Planning, & Feedback") [📦](#platform-jlongster "Packaging/porting to new platform") | [

_{Herb Hagely}](https://github.com/hhagely)
[💡](#example-hhagely "Examples") | [

_{Alex Wendte}](http://www.wendtedesigns.com/)
[💡](#example-themostcolm "Examples") | | [

_{Monica Powell}](http://www.aboutmonica.com)
[📖](https://github.com/kentcdodds/react-testing-library/commits?author=M0nica "Documentation") | [

_{Vitaly Sivkov}](http://sivkoff.com)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=sivkoff "Code") | [

_{Weyert de Boer}](https://github.com/weyert)
[🤔](#ideas-weyert "Ideas, Planning, & Feedback") [👀](#review-weyert "Reviewed Pull Requests") | [

_EstebanMarin](https://github.com/EstebanMarin)
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_{Victor Martins}](https://github.com/vctormb)
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_{Royston Shufflebotham}](https://github.com/RoystonS)
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_chrbala](https://github.com/chrbala)
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_{Donavon West}](http://donavon.com)
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_{Richard Maisano}](https://github.com/maisano)
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_{Marco Biedermann}](https://www.marcobiedermann.com)
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_{Alex Zherdev}](https://github.com/alexzherdev)
[🐛](https://github.com/kentcdodds/react-testing-library/issues?q=author%3Aalexzherdev "Bug reports") [💻](https://github.com/kentcdodds/react-testing-library/commits?author=alexzherdev "Code") | [

_{André Matulionis dos Santos}](https://twitter.com/Andrewmat)
[💻](https://github.com/kentcdodds/react-testing-library/commits?author=Andrewmat "Code") [💡](#example-Andrewmat "Examples") [⚠️](https://github.com/kentcdodds/react-testing-library/commits?author=Andrewmat "Tests") | This project follows the [all-contributors][all-contributors] specification. Contributions of any kind welcome! ## Issues _Looking to contribute? Look for the [Good First Issue][good-first-issue] label._ ### 🐛 Bugs Please file an issue for bugs, missing documentation, or unexpected behavior. [**See Bugs**][bugs] ### 💡 Feature Requests Please file an issue to suggest new features. Vote on feature requests by adding a 👍. This helps maintainers prioritize what to work on. [**See Feature Requests**][requests] ### ❓ Questions For questions related to using the library, please visit a support community instead of filing an issue on GitHub. - [Spectrum][spectrum] - [Reactiflux on Discord][reactiflux] - [Stack Overflow][stackoverflow] ## LICENSE MIT [npm]: https://www.npmjs.com/ [node]: https://nodejs.org [build-badge]: https://img.shields.io/travis/kentcdodds/react-testing-library.svg?style=flat-square [build]: https://travis-ci.org/kentcdodds/react-testing-library [coverage-badge]: https://img.shields.io/codecov/c/github/kentcdodds/react-testing-library.svg?style=flat-square [coverage]: https://codecov.io/github/kentcdodds/react-testing-library [version-badge]: https://img.shields.io/npm/v/react-testing-library.svg?style=flat-square [package]: https://www.npmjs.com/package/react-testing-library [downloads-badge]: https://img.shields.io/npm/dm/react-testing-library.svg?style=flat-square [npmtrends]: http://www.npmtrends.com/react-testing-library [spectrum-badge]: https://withspectrum.github.io/badge/badge.svg [spectrum]: https://spectrum.chat/react-testing-library [license-badge]: https://img.shields.io/npm/l/react-testing-library.svg?style=flat-square [license]: https://github.com/kentcdodds/react-testing-library/blob/master/LICENSE [prs-badge]: https://img.shields.io/badge/PRs-welcome-brightgreen.svg?style=flat-square [prs]: http://makeapullrequest.com [donate-badge]: https://img.shields.io/badge/$-support-green.svg?style=flat-square [coc-badge]: https://img.shields.io/badge/code%20of-conduct-ff69b4.svg?style=flat-square [coc]: https://github.com/kentcdodds/react-testing-library/blob/master/CODE_OF_CONDUCT.md [github-watch-badge]: https://img.shields.io/github/watchers/kentcdodds/react-testing-library.svg?style=social [github-watch]: https://github.com/kentcdodds/react-testing-library/watchers [github-star-badge]: https://img.shields.io/github/stars/kentcdodds/react-testing-library.svg?style=social [github-star]: https://github.com/kentcdodds/react-testing-library/stargazers [twitter]: https://twitter.com/intent/tweet?text=Check%20out%20react-testing-library%20by%20%40kentcdodds%20https%3A%2F%2Fgithub.com%2Fkentcdodds%2Freact-testing-library%20%F0%9F%91%8D [twitter-badge]: https://img.shields.io/twitter/url/https/github.com/kentcdodds/react-testing-library.svg?style=social [emojis]: https://github.com/kentcdodds/all-contributors#emoji-key [all-contributors]: https://github.com/kentcdodds/all-contributors [set-immediate]: https://developer.mozilla.org/en-US/docs/Web/API/Window/setImmediate [guiding-principle]: https://twitter.com/kentcdodds/status/977018512689455106 [data-testid-blog-post]: https://blog.kentcdodds.com/making-your-ui-tests-resilient-to-change-d37a6ee37269 [dom-testing-lib-textmatch]: https://github.com/kentcdodds/dom-testing-library#textmatch [bugs]: https://github.com/kentcdodds/react-testing-library/issues?q=is%3Aissue+is%3Aopen+label%3Abug+sort%3Acreated-desc [requests]: https://github.com/kentcdodds/react-testing-library/issues?q=is%3Aissue+sort%3Areactions-%2B1-desc+label%3Aenhancement+is%3Aopen [good-first-issue]: https://github.com/kentcdodds/react-testing-library/issues?utf8=✓&q=is%3Aissue+is%3Aopen+sort%3Areactions-%2B1-desc+label%3A"good+first+issue"+ [reactiflux]: https://www.reactiflux.com/ [stackoverflow]: https://stackoverflow.com/questions/tagged/react-testing-library