How to testing code modules?

What specific guidance are you looking for? You would test that, using phpunit provided, like you would test any class. The testing tools aren't complete yet, but you can look at any of the tests in /system to see how to use things. You can also test controllers, and more with the existing tools. I'm very close to having HTTP testing tools ready, which included a refactor of how some of the core code worked to make testing even easier, and hope to have that pushed to the repo by the end of the week. Having to update all of the other tests in the system to work with the refactored CodeIgniter.php and CIUnitTestCase. And I need to write up that docs for it.

If you have specific questions we can be of more help.

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