Files
react/packages/react-test-renderer
Luna Ruan df14b5bcc1 add new IDs for each each server renderer instance and prefixes to distinguish between each server render (#18576)
There is a worry that `useOpaqueIdentifier` might run out of unique IDs if running for long enough. This PR moves the unique ID counter so it's generated per server renderer object instead. For people who render different subtrees, this PR adds a prefix option to `renderToString`, `renderToStaticMarkup`, `renderToNodeStream`, and `renderToStaticNodeStream` so identifiers can be differentiated for each individual subtree.
2020-05-07 20:46:27 -07:00
..
2020-02-27 14:11:40 -08:00

react-test-renderer

This package provides an experimental React renderer that can be used to render React components to pure JavaScript objects, without depending on the DOM or a native mobile environment.

Essentially, this package makes it easy to grab a snapshot of the "DOM tree" rendered by a React DOM or React Native component without using a browser or jsdom.

Documentation:

https://reactjs.org/docs/test-renderer.html

Usage:

const ReactTestRenderer = require('react-test-renderer');

const renderer = ReactTestRenderer.create(
  <Link page="https://www.facebook.com/">Facebook</Link>
);

console.log(renderer.toJSON());
// { type: 'a',
//   props: { href: 'https://www.facebook.com/' },
//   children: [ 'Facebook' ] }

You can also use Jest's snapshot testing feature to automatically save a copy of the JSON tree to a file and check in your tests that it hasn't changed: https://facebook.github.io/jest/blog/2016/07/27/jest-14.html.