jest-environment-happy-dom

Happy DOM Jest Environment

A Jest DOM environment with support for web components.

Read more about Happy DOM

DOM Features

• Custom Elements (Web Components)

• Shadow Root (Shadow DOM)

• Mutation Observer

• Tree Walker

• Fetch

  And much more..

How to Install

npm install jest-environment-happy-dom --save-dev

Setup

Jest uses jsdom as test environment by default. In order to tell Jest to use a different environment we will either have to set a CLI attribute or add a property your Jest config file.

CLI

This guide will explain how to tell Jest to use Happy DOM by setting a CLI attribute.

1. Edit package.json

2. Add "--env=jest-environment-happy-dom" as an attribute to your Jest command.

   {
       ...
       "scripts": {
           "test": "jest --env=jest-environment-happy-dom"
       },
       "devDependencies": {
           "jest": "^24.8.0",
           "jest-environment-happy-dom": "^0.0.1"
       }
   }
   

3. Save the file.

Configuration File

This guide will explain how to tell Jest to use Happy DOM by adding a property to your Jest config file.

1. Edit your Jest config file (usually jest.config.js)
2. Add the following to it:

   {
     ...
     "testEnvironment": "jest-environment-happy-dom"
   }
   

3. Save the file.

Known Limitations

Happy DOM supports the most common functionality of a DOM, but there are some features that are not supported yet.

If you have a need for a missing feature or if you have found a bug, please let me know, and I will do my best to fix it.

Release Notes

Version	Date	Description
0.0.1	2019-09-13	Initial release.

How to Develop

Installation

npm install

Compilation

npm run compile

Run Watcher

npm run watch