
Jest · Delightful JavaScript Testing
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Getting Started - Jest
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 …
Jest 30: Faster, Leaner, Better · Jest - jestjs.io
Jun 4, 2025 · Today we are happy to announce the release of Jest 30. This release features a substantial number of changes, fixes, and improvements. While it is one of the largest major …
Testing React Apps · Jest
See React: Function and Class Components. Reminders that with Class components, we expect Jest to be used to test props and not methods directly. Now let's use React's test renderer and …
Expect - Jest
Jest adds the inlineSnapshot string argument to the matcher in the test file (instead of an external .snap file) the first time that the test runs. Check out the section on Inline Snapshots for more …
Configuring Jest · Jest
Jest has default serializers for built-in JavaScript types, HTML elements (Jest 20.0.0+), ImmutableJS (Jest 20.0.0+) and for React elements. See snapshot test tutorial for more …
Jest CLI Options
The jest command line runner has a number of useful options. You can run jest --help to view all available options. Many of the options shown below can also be used together to run tests …
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 …
Getting Started - Jest
You can use that in your configuration to conditionally setup only the compilation needed for Jest, e.g. // You can use isTest to determine what presets and plugins to use.
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, …