Jest · Delightful JavaScript Testing 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 quickly Jest is well-documented, requires little configuration and can be extended to match your requirements Jest makes testing delightful
Getting Started - Jest Using Parcel Jest can be used in projects that use parcel-bundler to manage assets, styles, and compilation similar to webpack Parcel requires zero configuration Refer to the official docs to get started Using TypeScript Via babel Jest supports TypeScript, via Babel First, make sure you followed the instructions on using Babel above
Globals - Jest In your test files, Jest puts each of these methods and objects into the global environment You don't have to require or import anything to use them However, if you prefer explicit imports, you can do import {describe, expect, test} from '@jest globals'
Jest 30: Faster, Leaner, Better · Jest - jestjs. io Jest is fast, but due to Jest's test isolation, slow user code often exacerbates performance issues and leads to slow test runs When tests leave behind open handles like unclosed timers or connections to other services, it can cause Jest to hang or slow down Jest 30 has gotten better at detecting and reporting these issues, which helps you identify and fix slow or problematic tests more
Need help? - Jest Need help? Jest is worked on by a team of volunteers in their spare time You can find out ways to talk to community members below
Testing Web Frameworks · Jest Jest is a universal testing platform, with the ability to adapt to any JavaScript library or framework In this section, we'd like to link to community posts and articles about integrating Jest into popular JS libraries