Lee Blue

Pound makes it really easy to write and run unit tests for WordPress plugins.

Pound :: Easy Unit Testing For WordPress

We need to start writing testable code in WordPress plugins! There are very few academic projects in this area, and Lee Blue has put forward a really cool plugin here. This plugin takes a unique approach in that it is extremely simple and limited in what it can do. It's a great start for programmers looking to get into testing their plugins. 

Awesome start!

Easily write unit tests for WordPress plugins

nunomorgadinho

Ana Aires

Enables you to create unit tests for your plugins, run and check the results in a centralized way. 
Since version 2.0 it has phpunit bundled in so all you need to get started with unit testing is to install this plugin.
Its based on the WordPress automated system but distributed as a plugin. Also it does not require a new database and a new configuration file so when you create your unit tests pay special attention to your database access so you keep a consistent database.
Every unit test must extend PHPUnit_Framework_TestCase and be included in the testcase directory you will find under the wp-unit plugin directory.
To run the tests go to the Unit Testing menu in the admin panel and press the Run buttom. The results will be displayed on the same page.
Feel free to give us some feedback.

wp-unit

Enables you to create unit tests for your plugins, run and check the results in a centralized way.

Pound :: Easy Unit Testing For WordPress vs wp-unit