Google JS Test is a JavaScript unit testing framework that runs on the V8 JavaScript Engine, the same open source project that is responsible for Google Chrome’s super-fast JS execution speed. Google JS Test is used internally by several Google projects, and we’re pleased to announce that it has been released as an open source project.

Features of Google JS Test include:
  • Extremely fast startup and execution time, without needing to run a browser.
  • Clean, readable output in the case of both passing and failing tests.
  • An optional browser-based test runner that can simply be refreshed whenever JS is changed.
  • A built-in mocking framework that requires minimal boilerplate code (e.g. no $tearDown or $verifyAll calls), with style and semantics based on the Google C++ Mocking Framework.
  • A system of matchers allowing for expressive tests and easy to read failure output, with many built-in matchers and the ability for the user to add their own.

See the Google JS Test project home page for a quick introduction, and the getting started page for a tutorial that will teach you the basics in just a few minutes.

By Aaron Jacobs, Google Engineer