Skip to content

dabapps/jest-matcher-react-shallow-snapshot

Repository files navigation

jest-matcher-react-shallow-snapshot

A jest matcher for shallow rendered React component snapshots

About

This is a fork of @jakesidsmith/jest-matcher-react-shallow-snapshot.

This is a jest matcher that allows you to easily create shallow snapshots of React components will full support for:

  • React.memo
  • React.forwardRef
  • React.Fragment
  • React.createContext (Provider and Consumer)
  • ReactDOM.createPortal
  • Functional components
  • Component classes

The output of this matcher is far more informative than other existing solutions, providing context of memo wrapped components, fragments, etc, and does not require importing a renderer for each of your test files.

This relies on react-shallow-renderer under the hood, which you could use without the jest matcher if you prefer / are using another test suite.

Check out the react-shallow-renderer readme for some examples of the snapshot output.

Example

expect(<MyComponent />).toMatchReactShallowSnapshot();

Install

Install as a dev dependency (-D is short for --save-dev)

npm i @dabapps/jest-matcher-react-shallow-snapshot -D

Configuration

Jest config

This library requires you to define a setupFilesAfterEnv entry in your jest config (or setupTestFrameworkScriptFile for older versions of jest).

This should point to a file which will be used to initialize custom matchers:

module.exports = {
  setupFilesAfterEnv: [
    '<rootDir>/path/to/custom-matchers.js'
  ]
};

If you don't already have a such a file you should create one, and then simply import this library in that file:

import '@dabapps/jest-matcher-react-shallow-snapshot';

If you are using TypeScript, importing this file from your setup file should apply the types needed to call .toMatchReactShallowSnapshot. If it doesn't, then make sure that the setup file is included in your tsconfig.

Usage

Now you can simply render a react component and expect it to match your shallow snapshot:

expect(<MyComponent />).toMatchReactShallowSnapshot();

Updating this fork from upstream

Ensure you have added a remote upstream in git e.g.

git remote add upstream [email protected]:JakeSidSmith/jest-matcher-react-shallow-snapshot.git

Create a new branch (from master) and run the following to pull changes from upstream:

git fetch upstream
git pull upstream master