Integration Tests

AKA "How do I test classes that extend or override core Magento classes?"

Testing a class that has been extended from a core Magento class is as easy as extending the class itself. Simply extend the unit test for the class you've overridden, and then add your own tests into the extended class.

For instance, let's say you have a module, named "Foo_Bar", which extends Mage_Catalog. Specifically, we have a class, Foo_Bar_Model_Product which extends Mage_Catalog_Model_Product, the unit test for the original Mage file is Mage/Catalog/Test/Model/Product.php, so the test class (Foo/Bar/Test/Model/Product.php) must extend Mage_Catalog_Test_Model_Product