Reviewing code is hard, especially because reviewers tend to inherit some responsibility for problems the code causes later. That can lead to churn while they try to develop confidence that new submissions are ready to merge.
I submit a lot of code for review, so I’ve been through a lot of that churn. Over the years I’ve found a few things that help make it easier for my reviewers to develop confidence in my submissions, so I decided to write a checklist. ✔️
The code I write lives in diverse repos governed by diverse requirements. A lot of the items in my checklist are there to help make sure I don’t mix up the issues I’m working on or the requirements of the repos I’m working in.
This isn’t a guide on writing good code. You can spend a lifetime on that topic. This is a quick checklist I use to avoid common mistakes.
This is written for Pull Requests submitted in git repos hosted on GitHub, but most of its steps are portable to other platforms (e.g. Perforce). It assumes common project features, like a contributing guide. Adjust as needed.
Immediately before submitting:
- Reread the issue.
- Merge the latest changes from the target branch (e.g.
- Reread the diff line by line.
- Rerun all tests. If the project doesn’t have automated tests, you can still:
- Run static analysis tools on every file you changed.
- Manually exercise new functionality.
- Manually exercise existing functionality to make sure it hasn’t changed.
- Check if any documentation needs to be updated to reflect your changes.
- Check the rendering of any markup files (e.g.
README.md) in the GitHub UI.
- There are remarkable differences in how markup files render on different platforms, so it’s important to check them in the UI where they’ll live.
- Reread the project’s contributing guide.
- Write a description that:
- Links to the issue it addresses.
- Gives a plain English summary of the change.
- Explains decisions you had to make. Like:
- Why you didn’t clean up that one piece of messy code.
- How you chose the libraries you used.
- Why you expanded an existing module instead of writing a new one.
- How you chose the directory and file names you did.
- Why you put your changes in this repo, instead of that other one.
- Lists all the tests you ran. Include relevant output or screenshots from manual tests.
There’s no perfect way to submit code for review. That’s why we still need humans to do it. The creativity and diligence of the engineer doing the work are more important than this checklist. Still, I’ve found that these reminders help me get code through review more easily.
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