Code review is a great software instrument and you should definitely use it to improve the quality of your code. But like any other tool, it may be misused sometimes. That’s why I came up with a list of best practices to guide you when reviewing your peers’ code.

1. Code review is not testing: Code review is a developer-to-developer business and it doesn’t involve any testing. Code review should check if the task requirements are met in the cleanest possible way.
2. You don’t tell what to code review: The same way you don’t tell a tester what to test, you should never tell your peer what to review. The magic of peer review comes from your peer own perspective on the current task design and implementation. Two minds are always better than one.
3. You should always check all changes: Bugs may be hidden anywhere and you should search for them diligently. To have the whole picture you need to go through all changes.
4. Requirements first: Requirements are the most important driving force. After all that’s what the customer is paying for. If the current changes are suboptimal you need to reopen the issue. If you happen to spot other code sections that need to be refractored you should create new issues instead of reopening the current one. The “single responsibility principle” applies to tasks as well as to coding.
5. One-to-many activity: If you can’t make sure you grasp the code change intention it’s safer to ask somebody else to review it further.
6. A way of learning: Code review is a great learning technique especially on large projects. Ideally you should become familiar with every aspect of your project, but if the project is too large you can at least specialize in multiple modules.

Happy code reviewing!

Source: http://www.dzone.com/