acdlite [react-test-renderer] Jest matchers for async tests (#13236)
Adds custom Jest matchers that help with writing async tests:

- `toFlushThrough`
- `toFlushAll`
- `toFlushAndThrow`
- `toClearYields`

Each one accepts an array of expected yielded values, to prevent
false negatives.

Eventually I imagine we'll want to publish this on npm.
Latest commit 71b4e99 Jul 19, 2018


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.



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

const renderer = ReactTestRenderer.create(
  <Link page="">Facebook</Link>

// { type: 'a',
//   props: { href: '' },
//   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: