Jest is a JavaScript testing framework designed to ensure correctness of any JavaScript codebase. It allows you to write tests with an approachable, familiar and feature-rich API that gives you results …

Start using jest in your project by running `npm i jest`. There are 13364 other projects in the npm registry using jest.

Development of Jest happens in the open on GitHub, and we are grateful to the community for contributing bugfixes and improvements. Read below to learn how you can take part in improving Jest.

Jul 12, 2025 · Jest is a JavaScript testing framework developed by Facebook, designed primarily for unit testing React applications. However, it can be used for testing any JavaScript codebase.

Feb 26, 2025 · In this section, you'll explore Jest’s core features and learn how to write and run tests effectively. Before diving into Jest, ensure you have Node.js installed, preferably the latest LTS …

JEST definition: 1. something that is said or done in order to be funny: 2. intended as a joke and not said…. Learn more.

This tutorial covers everything you need to know about using Jest to test JavaScript, a simple and powerful testing framework. Whether you're a beginner or have some experience, this guide will help …

Jest is used by Facebook to test all JavaScript code including React applications. One of Jest's philosophies is to provide an integrated “zero-configuration” experience.

Jan 10, 2019 · (Note that it's idiomatic to tell a joke or play a joke on and to speak in jest.) Jests are also described as playful banter, droll tales - although their meaning has evolved over time.

Jest can be used in projects that use webpack to manage assets, styles, and compilation. webpack does offer some unique challenges over other tools. Refer to the webpack guide to get started.