Conventional Comments

By Paul Slaughter

Comments that are easy to grok and grep

Comments like this are unhelpful…

Caterpillar

@caterpillar

This is not worded correctly.

By simply prefixing the comment with a label, the intention is clear and the tone dramatically changes.

Caterpillar

@caterpillar

suggestion: This is not worded correctly.

Caterpillar

@caterpillar

nitpick (non-blocking): This is not worded correctly.

Labels also prompt the reviewer to give more actionable comments.

Caterpillar

@caterpillar

suggestion: This is not worded correctly.

Can we change this to match the wording of the marketing page?

Labeling comments saves hours of undercommunication and misunderstandings. They are also parseable by machines!

Examples

Alice

@alice

suggestion: Let's avoid using this specific function…

If we reference much of a function marked “Deprecated”, it is almost certain to disagree with us, sooner or later.

7 of Spades

@7ofspades

issue (ux,non-blocking): These buttons should be red, but let's handle this in a follow-up.

Target audience

Conventional Comments is a standard for formatting comments of any kind of review/feedback process, such as:

Format

Adhering to a consistent format improves reader's expectations and machine readability. Here's the format we propose:

<label> [decorations]: <subject> [discussion]
  • label - This is a single label that signifies what kind of comment is being left.
  • subject - This is the main message of the comment.
  • decorations (optional) - These are extra decorating labels for the comment. They are surrounded by parentheses and comma-separated.
  • discussion (optional) - This contains supporting statements, context, reasoning, and anything else to help communicate the “why” and “next steps” for resolving the comment.

For example:

A. Mouse

@amouse

question (non-blocking): At this point, does it matter which thread has won?

Maybe to prevent a race condition we should keep looping until they've all won?

Can be automatically parsed into:

{ "label": "question", "subject": "At this point, does it matter which thread has won?", "decorations": ["non-blocking"], "discussion": "Maybe to prevent a race condition we should keep looping until they've all won?"
}

Labels

We strongly suggest using the following labels:

praise: Praises highlight something positive. Try to leave at least one of these comments per review. Do not leave false praise (which can actually be damaging). Do look for something to sincerely praise.
nitpick: Nitpicks are small, trivial, but necessary changes. Distinguishing nitpick comments significantly helps direct the reader's attention to comments requiring more involvement.
suggestion: Suggestions propose improvements to the current subject. It's important to be explicit and clear on what is being suggested and why it is an improvement. Consider using patches and the blocking or non-blocking decorations to further communicate your intent.
issue: Issues highlight specific problems with the subject under review. These problems can be user-facing or behind the scenes. It is strongly recommended to pair this comment with a suggestion. If you are not sure if a problem exists or not, consider leaving a question.
question: Questions are appropriate if you have a potential concern but are not quite sure if it's relevant or not. Asking the author for clarification or investigation can lead to a quick resolution.
thought: Thoughts represent an idea that popped up from reviewing. These comments are non-blocking by nature, but they are extremely valuable and can lead to more focused initiatives and mentoring opportunities.
chore: Chores are simple tasks that must be done before the subject can be “officially” accepted. Usually, these comments reference some common process. Try to leave a link to the process description so that the reader knows how to resolve the chore.

Feel free to diverge from this specific list of labels if it seems appropriate.

Decorations

Decorations give additional context for a comment. They help further classify comments which have the same label (for example, a security suggestion as opposed to a test suggestion).

Cheshire Cat

@cheshirec

suggestion (security): I'm a bit concerned that we are implementing our own DOM purifying function here…

Could we consider using the framework instead?

Cheshire Cat

@cheshirec

suggestion (test,if-minor): It looks like we're missing some unit test coverage that the cat disappears completely.

Decorations may be specific to each organization. If needed, we recommend establishing a minimal set of decorations (leaving room for discretion) with no ambiguity.

Possible decorations include:

(non-blocking) A comment with this decoration should not prevent the subject under review from being accepted. This is helpful for organizations that consider comments blocking by default.
(blocking) A comment with this decoration should prevent the subject under review from being accepted, until it is resolved. This is helpful for organizations that consider comments non-blocking by default.
(if-minor) This decoration gives some freedom to the author that they should resolve the comment only if the changes ends up being minor or trivial.

Adding a decoration to a comment should improve understandability and maintain readability. Having a list of many decorations in one comment would conflict with this goal.

More examples

Mad Hatter

@hatter

nitpick: little star => little bat

Can we update the other references as well?

Alice

@alice

chore: Let's run the jabber-walk CI job to make sure this doesn't break any known references.

Here are the docs for running this job. Feel free to reach out if you need any help!

Cheshire Cat

@cheshirec

praise: Beautiful test!

Best Practices

These will be expanded later, but for now, here are some best practices for writing helpful review feedback:

  • Mentoring pays off exponentially
  • Leave actionable comments
  • Combine similar comments
  • Replace “you” with “we”

Want to help make this better?

Check out the GitLab project for this site. Issues and Merge Requests are welcome!

Prior art

The characters used in the examples are respectfully adapted from Lewis Carroll's Alice in Wonderland, illustrated by John Tenniel.