The YUI team recently released a new version of the YUI Test framework, aimed at the YUI 3.0 library.  This article from the YUI blog describes some of the new features in more detail, but probably the biggest feature for many will be the support for mock objects.  Developers accustomed to having mock object support in their favorite server-side platform can now bring their mocking skills and expertise to JavaScript in the browser.

This is not to say that mock objects are the only way to go – I’ve heard arguments both for and against mocking for years.  But for those that want it, it’s now there in YUI Test.  Yes, we’ve had jsmock for some time, and I’m not knocking it.  I do think having a good integrated experience for people in the JS testing world will continue to help the adoption of testing practices in the front-end world.  The less friction there is in getting started, the more likely it is people will adopt it.

Kudos to the YUI team for your continued success in moving YUI forward.