What Is It?
Analyzing and evaluating code without executing the program. Syntax, comments, naming conventions, and functions of the code are reviewed.
When Should it be Done?
Should be conducted in real time, every time a change is saved. Linting should as be done as a part of continuous integration.
Checklists, manual or automated tools, PHP CS (Code Sniffer), JS Hint
Learn more about other method of dev testing in our white paper, Your Guide to Development Testing.