Why we test Create, Read, Update and delete functions, they are generated by the Yii framework and i guess that they are already tested in the developement precess of the framework and the yii’s goal is the reuse of code and DRY, is there an explaination for that?!!
The code IS tested… but anything other can go wrong… for example database user permission can be set wrong… or something similar…
Besides that: In contrast to the framework code itself, the CRUD code represents a basis for your application. You usually will customize this code.
Please also refer to the "Was all that testing really necessary?" section on page 73 (chapter 5) that addresses this very topic.