qooxdoo comes with its own, nicely integrated unit testing environment and the corresponding application called Testrunner. While being similar to JSUnit, the solution that ships with the qooxdoo SDK does not require any additional software.
If you look at the component section of a qooxdoo distribution, you will find the Test Runner tailored to test the functionality of the qooxdoo framework. It provides a convenient interface to test classes that have been written to that end. You can run single tests, or a whole suite of them at once.
But the Test Runner framework can be deployed for your own application. It provides a GUI, a layer of infrastructure and a certain interface for arbitrary test classes. You can write your own test classes and take advantage of the Test Runner environment.