Code Review Best Practice

Important!! When you add the sign-off member to your Pull Request, please not only add this member to reviewers, but also add to assignees. Adding to assignees will make us count the sign-off correctly. Thanks!

Why code review

Ensure more than one person would be familiar with each piece of code.
Enhance readability
Knowledge stays within the company

Requirements:

Every pull requests requires:

Code-reviewers (1-to-many volunteer nominations)
One sign-off member (limited committee)

Each commits requires:

Write git commit message in English

Having your code reviewed

Review your own code and look at your own diffs before submitting code for review
Make sure they pass all builds as well as all tests and code quality checks before assigning reviewers
Try to keep the code review changes small (ex. under 300 lines)
Be grateful for the reviewer’s suggestions (“Good call. I’ll make that change.”)
Explain why and how the implementation works at a high level. Simple outlines or diagrams are very helpful.
Push commits based on earlier rounds of feedback as isolated commits to the branch. Do not squash until the branch is ready to merge. Reviewers should be able to read individual updates based on their earlier feedback.
Try to respond to every comment

While you are reviewing code

Understand why the change is necessary (fixed a bug, improved the user experience or refactored the existing code)
Identify ways to simplify the code while still solving the problem
If discussions turn too philosophical or academic, move the discussion offline. In the meantime, let author make the final decision on alternative implementations
Offer alternative implementations, but assume the author already considered them. (“What do you think about using a custom validator here?”)
Sign off on the pull request with a thumbs up, “Ready to merge”, or “LGTM” comment
Remember that you are here to provide feedback, not to be a gatekeeper

How to write a git commit message

Separate subject from body with a blank line
Limit the subject line to 50 characters
Capitalize the subject line
Do not end the subject line with a period
Use the imperative mood in the subject line
Wrap the body at 72 characters
Use the body to explain what and why vs. how