Wallaby.js runs your JavaScript tests immediately as you type and displays execution results in your code editor. It also provides beautiful test and code coverage reports that are updated in realtime.


What is wallaby.js?

Wallaby.js is an integrated test runner that enables highly productive JavaScript (or TypeScript, or CoffeeScript) unit testing workflows. It runs your unit tests immediately as you type and displays various execution results, including code coverage and inline messages, right inside your code editor. The tool is insanely fast, because it only executes tests affected by your code changes and runs your tests in parallel.

Wallaby.js is great for doing JavaScript (or TypeScript, or CoffeeScript) TDD (Test-driven development) or BDD (Behavior Driven Development), while also working nicely for other approaches.

There is no vendor, API or framework lock-in when using Wallaby.js, because the tool just uses your existing testing framework and assertion libraries. You get a productivity boost with Wallaby.js, but you will always be able to run your tests without Wallaby.js.

Once you have Wallaby.js installed and running in any of the supported editors, you may also use the Wallaby.js browser app to get realtime test execution and code coverage reports that are connected to your editor.

Where can I find more information, such as a list of features, tutorials, samples?

You can find more information, detailed tutorials and sample project links in our documentation.

Who is using Wallaby.js?

Thousands of individual professional developers and companies (including many of Fortune 500 companies and well-known tech giants) all over the world have already become more productive by using Wallaby.js. Even software development tools vendors, such as our friends from JetBrains, trust Wallaby.js to help build their development tools.

What are our users saying?

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What about a list of main features?

  • Supports continuous testing in your code editor:
    • WebStorm, IntelliJ IDEA, PhpStorm, Rider, RubyMine, PyCharm
    • Visual Studio Code
    • Atom Text Editor
    • Visual Studio 2017,
      Visual Studio 2019
    • Sublime Text
  • Supports browser code unit testing (via Chrome, PhantomJs, Electron or node.js) and node.js unit testing.
  • Shows live test coverage.
  • Allows quick inspection of object values.
  • Provides beautiful realtime test and coverage reports.
  • Shows failed expectations, errors and console.log messages inline, where and when they occur.
  • Shows compact and side-by-side diff views for failing equality assertions and snapshots.
  • Supports many testing frameworks (Jasmine, QUnit, Mocha, Jest + snapshots, and AVA).
  • Supports ES.next, JSX, Babel.
  • Supports TypeScript, CoffeeScript, Flow.
  • Supports Webpack and Browserify.
  • Extensible via preprocessors, compilers and more.
  • Runs tests affected by code changes.
  • Runs tests in parallel.
  • Runs selected test(s), can update individual test(s) snapshots.

How is Wallaby.js different from other test runners (e.g. Karma, Jest CLI, etc.)?

With other test runners you either need to run your tests manually, or, at best, configure them to run the tests when you save your source code files. Those runners either execute all of your tests or, at best, all tests in all spec files affected by all uncommitted code changes, even if you are primarily editing just one file. So, as your project grows, it takes more and more time to complete the task. The test execution results are displayed somewhere outside of your code editor, and constant context switching to view the results is a productivity killer.

Wallaby.js runs your unit tests immediately as you type, no need to run anything manually, there's even no need to save files. The tool calculates and runs the minimum required number of tests affected by your code changes, often it is just a single test - and no other testing tool is capable of operating on this level. So no matter how large your project grows - the feedback is almost instant with Wallaby.js. Test execution results, including code coverage, are displayed and updated in real time right where you need it — in your code editor, next to the line of code that you're editing.

What technologies does Wallaby.js support?

Wallaby supports lots of technologies, and we have a collection of sample projects with configuration files for different tools, frameworks and languages such as Jasmine, Mocha, QUnit, AVA, Jest, Webpack, Browserify, ES6 and ES7 via Babel, TypeScript, CoffeeScript, React, Angular, Vue, and node.js. You can find details of all supported technologies in our documentation.

Do I have to install any other applications with Wallaby.js?

No. All you need to install is the Wallaby.js plugin for your code editor, period. No new command line tools or browser plugins. Our goal is not to add more things between you and the feedback from your tests. In fact, it's the opposite: Wallaby.js eliminates unnecessary context switching, so it's just you and your test feedback, right where and when you write your code.

Who stands behind Wallaby.js?

At the core of our team are professional JavaScript developers and professional development tools makers. Not only do we know and love the language and the ecosystem, but we have also dedicated our careers to making programmers happier and more productive.

Where is your changelog, and what does the roadmap for Wallaby.js look like?

Our changelog is in our public repository.

Wallaby.js roadmap: