Testing is a crucial part of ensuring that software continues to work as the initial design expected. Things often tend to break when changing existing codebases and often not directly in the places you are working on when errors occur.
This is where automated testing can help. If done correctly critical parts of your site, module and/or plugin can be tested in such a way that ensures you are notified when anything stops working as expected and before shipping any code to production. Reducing bugs before they are discovered by clients in production saved you the time of debugging the bug and communicating with the client, win-win.
# Craft Testing Framework
As of 3.2, Craft provides a formalized testing framework that is based on Codeception (opens new window) and implements the Yii 2 codeception module (opens new window).
On top of all the tools that Codeception and Yii 2 natively provide for testing. Craft adds its own layer of support to ensure Craft specific concepts such as Elements & Project config are supported.
Ready to rock? Start by reading a description of what testing is within Craft as well as how to test using Codeception (opens new window). Then there is a handy setup guide to setup your test suite.