9 Code Review Tips

For everyone:

  • Review the right things, let tools do the rest

You don’t need to argue over code style and formatting issues. There are plenty of toolswhich can consistently highlight those matters. Ensuring that the code is correct, understandable and maintainable is what’s important. Sure, style and formatting form part of that but you should let the tool be the one to point out those things.

  • Everyone should code review

Some people are better at it than others. The more experienced may well spot more bugs, and that’s important. But what’s more crucial is maintaining a positive attitude to code review in general and that means avoiding any ‘Us vs. Them’ attitude or making code review burdensome for someone.

  • Review all code

No code is too short or too simple. If you review everything, then, nothing gets missed. What’s more, that makes it a part of the process, a habit and not an afterthought.

  • Adopt a positive attitude

This is just as important for reviewers as well as submitters. Code reviews are not the time to get all alpha and exert your coding prowess. Nor do you need to get defensive. Go into it with a positive attitude of constructive criticism and you can build trust around the process.

For reviewers:

  • Code review often and for short sessions

The effectiveness of your reviews decreases after about an hour. So putting off reviews and doing them in one almighty session doesn’t help anybody. Set aside time throughout the day including breaks not to disrupt your own flow and help form a habit. Your colleagues will thank you for it. Waiting can be frustrating and they can resolve issues quicker whilst the code is still fresh in their heads.

  • It’s OK to say “It’s all good”

Don’t get picky, you don’t have to find an issue in every review.

  • Use a checklist

Code review checklistsensure consistency – they make sure everyone is covering what’s important and avoid common mistakes.

For submitters:

  • Keep the code short

Beyond 200 lines, the effectiveness of a review drops significantly. By the time you’re at more than 400, they become almost pointless.

  • Provide context

Link to any related tickets or the spec. There are code review toolsthat can help with that. Provide short but useful commit messages and plenty of comments throughout your code. It’ll help the reviewer and you’ll get fewer issues coming back.