This post is about code reviews, and the software that facilitates them.
I’ll be honest: I’m not a huge fan of code reviews, so a lot of what I speak of below can probably be dismissed as that from someone who blames their tools. Be that as it may, I do think there is room for improvements in the tooling used to review code, and this post touches on a few additional features which would help.
First I should say that I have no experience with dedicated code review tools. I’m mainly talking about code review tools that are part of hosted source code repository systems, like GitHub, GitLab, and Bitbucket. And since these are quite large and comprehensive systems, it might be that the priorities are different compared to a dedicated code review tool with a narrower focus. Pull requests and code reviews are just one of the many tasks that these systems need to handle, along with browsing code repositories, managing CI/CD runs, hosting binary releases, etc.
So I think it’s fair to say that such tools may not have the depth that a dedicated code review tool would have. After all, GitHub Actions does not have the same level of sophistication as something like Jenkins or BuildKite, either.
But even so, I’d say that there’s still room for improvement in the code review facilities that these systems do offer. Improvements that could be tailored more to the code review workflow. It’s a bit like using a text editor to manage your reminders. Yeah, you can use a text editor, but most of the features related specifically to reminders will not be available to you, and you’ll have to plug the feature gap yourself. Compare this to a dedicated reminder app, which would do a lot of the work for you, such as notifying you of upcoming reminders or having the means to marking an item as done.
So, what should be improved in the software that is used to review code? I can think of a few things:
Inbox: When you think about it, code reviews are a bit like emails and Jira tickets: they come to you and require you to action them in some way in order to get the code merged. But the level of attention you need to give them changes over time. If you’ve made comments on a review, there’s really no need to look at it again until the code has been updated or those the author has replied.
But this dynamic aspect of code reviews is not well reflected in most of these systems. Usually what I see is simply a list of pull requests that have not yet been approved or merged, and I have to keep track of the reviews that need my attention now myself, verses those that I can probably wait for action from others.
I think what would be better than a simple list would be something more of an inbox: a subset of the open reviews that are important to me now. As I action them, they’ll drop off the list and won’t come back until I need to action them again.
The types of reviews that I’d like to appear in the inbox, in the ordered listed below, would be the following:
- Ones that have been opened in which I’ve made comments that have been responded to — either by a code change or a reply — that I need to look at. The ones with more responses would appear higher in the list than the ones with less.
- Reviews that are brand new that I haven’t looked at yet, but others have.
- Brand new reviews that haven’t been looked at by anyone.
In fact, the list can be extended to filter out reviews that I don’t need to worry about, such as:
- Reviews that I’ve made comments on that have not been responded to yet. This indicates either that the author has not gotten around to it yet, in which case looking at the pull request again serves no purpose.
- Reviews that have enough approvals by others and do not necessarily need mine.
- Reviews that I’ve approved.
This doesn’t necessarily need to replace the list of open reviews: that might still be useful. But it will no longer be the primary list of reviews I need to work with during the day to day.
Approval pending resolution of comments: One thing I always find myself indecisive about is when I should hit that Approve button. Let’s say I’ve gone through the code, made some comments that I’d like the submitter to look at, but the rest of the code looks good. When should I approve the pull request? If I do it now, then the author may not have seen the comments or have indication that I’d like them to make changes, and will go ahead and merge.
I guess then the best time to approve it is when the changes are made. But that means the onerous is on me to remember to review the changes again. If the requests are trivial — such as renaming things — and I’d trust the person to make the changes and going through to review them once again is a waste of time.
This is where “Approval pending resolution of comments” would come in handy. Selecting this approval mode would mean that my approval would be granted once the author has resolve the outstanding review comments. This would not replace the regular approval mode: if there are changes which do require a re-review, I’d just approve it normally once I’ve gone through it again. But it’s one more way to let the workflow of code reviews work in my favour.
Speaking of review comments…
Review comment types: I think it’s a mistake to assume that all review comments are equal. Certainly in my experience I find myself unable to read the urgency of comments on the reviews I submit. I also find it difficult to telegraph in the comments that I make on code reviews of others. This usually results in longer comments with phrases such as “you don’t have to do this now, but…”, or “something to consider in the future…”
Some indication of the urgency of the comment alongside the comment itself would be nice. I can think of a system that has at least three levels:
- Request for change: this is the highest level. It’s an indication that you see something wrong with the code that must be changed. In these cases, these comments would need to be resolved with either a change to the code, or a discussion of some sort, but they need to be resolved before the code is merged.
- Request for improvement: This is a level lower, and indicates that there is something in the code that may need to be change, but not doing so would not block the code review. This can be used to suggest improvements to how things were done, or maybe to suggest an alternative approach to solving the problem. All those nitpicking comments can go here.
- Comments: This is the lowest level. It provides the way to make remarks about the code, but that require no further action from the author. Uses for this might be praise for doing something a certain way, or FYI type comments that the submitter may need to be aware of for future changes.
Notes to self: Finally, one thing that is on way too few systems that deal with shared data is the ability to annotate pull requests or the commented files with private notes. These won’t be seen by the author or any of the other reviewers, and are only there to facilitate making notes to self, such as things like “Looked at it, waiting for comments to be addressed”, or “review no longer pending”. This is probably the minimum, and would be less important if the other things are not addressed.
So that’s how I’d improve code review software. It may be that I’m the only one with this problem, and that others are perfectively able to review code effectively without these features. But I know they would work for me, and if I start seeing these in services like GitHub or GitLab, I probably would start using them.