React Testing Library
React Testing Library builds on top of
DOM Testing Library by adding
APIs for working with React components.
Projects created with
Create React Apphave out of the box support for React Testing Library. If that is not the case, you can add it via
npm install --save-dev @testing-library/react
yarn add --dev @testing-library/react
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.
React Testing Library is a very light-weight solution for testing React
components. It provides light utility functions on top of
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.
So rather than dealing with instances of rendered React components, your tests
will work with actual DOM nodes. The utilities this library provides facilitate
querying the DOM in the same way the user would. Finding form elements by their
label text (just like a user would), finding links and buttons from their text
(like a user would). It also exposes a recommended way to find elements by a
data-testid as an "escape hatch" for elements where the text content and label
do not make sense or is not practical.
This library encourages your applications to be more accessible and allows you to get your tests closer to using your components the way a user will, which allows your tests to give you more confidence that your application will work when a real user uses it.
This library is a replacement for Enzyme. While you can follow these guidelines using Enzyme itself, enforcing this is harder because of all the extra utilities that Enzyme provides (utilities which facilitate testing implementation details). Read more about this in the FAQ.
What this library is not:
- A test runner or framework
- Specific to a testing framework (though we recommend Jest as our preference, the library works with any framework. See Using Without Jest)
NOTE: This library is built on top of
DOM Testing Librarywhich is where most of the logic behind the queries is.
Have a look at the "What is React Testing library?" video below for an introduction to the library.
Also, don't miss this tutorial for React Testing Library.