SuperPermsTest
SuperPermsTest allows to test permission plugins that claim to support "SuperPerms" for their correctness and performance.
Introduction
Bukkit created a standard API for setting and retrieving permissions of players called "SuperPerms" and there are currently a handful of permissions plugins that claim to support that API. This plugin runs testcases (see the Test Details page) against such a plugin on the server, trying to spot faulty implementations, misconfigurations or performance problems with "SuperPerms".
For Server Admins
If you are just interested in the results of the testcases, head over to the Test Results section and take a look at them. Those results are from my home PC (4 core AMD 2.8 GHz, 4 GB Ram) and while your server will likely produce different times, the relation between the times should stay roughly the same.
If you want to run these tests yourself against the permission plugin you currently use on your server, you should go to the Test Setup section and read about what you'll have to do to successfully run these testcases (you'll have to choose a player for testing and give him some permission nodes). You may spot performance or configuration problems on your server that way.
For Plugin Developers
If your plugin uses "SuperPerms", you may want to take a look at the Test Results section. It will show you some expected times for how long a call to "player.hasPermission(...)" may take under certain circumstances. You can also setup the test plugin on your test server by following instructions on the Test Setup page to make sure that the permissions plugin you use for testing your plugin works correctly and therefore can be sure it is (not) your fault if something doesn't work.
For Permissions Plugin Developers
If you plan on supporting "SuperPerms" or to make drastic changes to your implementation, running the testcases provided by "SuperPermsTest" can help you to spot errors early, instead of waiting for people to give you obscure error reports like "it doesn't work. Fix it!". Also, you may use the test results on the Test Results page to convince people that your plugin works correctly, is fast enough etc. and that it has to be an user error that's causing the problems (e.g. misconfiguration).
Some other info
I don't claim that these testcases are complete, meaning that a plugin passing all testcases is not equal to it implementing SuperPerms 100%. But it means that most of the practical usecases of "SuperPerms" are covered.
The project is released under MIT license. It is open source and you can find it on github here: SuperPermsTest.
I have a twitter account, which I use to announce new versions of my plugins (mostly): 
