XulUnit A simple test framework for Firefox Extension Development

Gamelayers is the creator of PMOG a massively multiplayer online game, played through a custom
Firefox extension. The Gamelayers’ team is a Test Driven Development team and as such expected
to write unit tests for their extensions. However, after not finding an existing test framework
suitable for testing extensions from within the Firefox environment Gamelayers decided to write
their own.

In the spirt of “scratch your own itch”, we are happy to release the XulUnit framework for testing
Firefox extension using only Javascript.

XulUnit is based on the excellent Javascript test unit framework QUnit, which was written for JQuery.
We extended their framework in a couple of ways:

1. We changed the runtime environment to render to a XUL window, embedded directly inside the Firefox window. 2. We added support for pending tests, which display in the test results but don’t count as a pass or failure. 3. We included an example of a mocking library that can be used as fixtures or to stub our components of the Firefox application.