x/build/cmd/relnote: document RELNOTE marker rules

[dmitshur]

As far as I know at this time, the RELNOTE marker isn't documented anywhere.

I suspect this causes it to be used less often and not to its full potential.

For example, it's possible to write a string other than yes or y and then the entire string will be included in the generated notes. This means it's possible to write a part of release notes via the RELNOTE marker, not just say "yes". I only learned this today when reading cmd/relnote code, and it's possible more people would take advantage of this if they knew it also.

Perhaps it is already documented somewhere and then this bug is about making me learn that. I've looked in the package documentation and the wiki, with no luck. I've only found https://groups.google.com/d/msg/golang-dev/edmMTXNukjE/V2bh9Vt3CAAJ and #20102 where it was originally announced by @bradfitz, but those aren't good sources for long-term documentation.

Update: The RELNOTE marker is documented at https://golang.org/wiki/CodeReview#cl-directives.

/cc @golang/osp-team

[bcmills]

To be honest, I would rather we discourage the use of RELNOTE anyway. The RELNOTE marker makes it easy to add essentially a TODO for someone else to write a release note later, but doesn't actually assign anyone in particular to do it.

I think it's fine to defer writing the release notes — particularly if the CL author isn't comfortable writing English prose for publication — but in that case I would prefer that we add an explicit TODO to the release notes (with more context and a specific person assigned to fill it in), or to file a release-blocker+Documentation issue with an explicit assignee.

[ianlancetaylor]

I agree that that is the ideal, but we should not raise writing a release note, even a TODO note, as a blocker for external contributors who may not be familiar with our conventions. For those cases, it's easy for a maintainer to add a RELNOTE tag to the CL.

[bcmills]

@ianlancetaylor, it seems nearly as easy for a maintainer to add an open issue, which would allow significantly more visibility into the context. (For example, the issue can have a specific assignee and would be more visible in milestone tracking.)

Or, for that matter, it's easy enough for a maintainer to immediately send a followup CL to add the release note. I understand why it can be useful to separate the release-note writing from the contributor's CL, but I don't see the benefit in deferring the release notes as technical debt until the end of the cycle, and that is (empirically) how the RELNOTE tag tends to play out.

[ianlancetaylor]

You are assuming that a core team member is involved with every CL, and that is not the case. I really do not want to raise additional barriers to contribution. I agree that RELNOTE is not ideal, but it's not impossible to work with.

[andybons]

@ianlancetaylor I’m not sure I agree that it’s an unacceptable burden to place on a contributor. There are circumstances that may warrant an exception (English is not their primary language, for example), but as we would expect someone to add adequate documentation next to the code they’ve written, asking them to update an html file as well doesn’t seem too onerous.

It increases the barrier to contribution, but not by much. I’d rather have the effort spread across all authors and not on a select few who should be focused primarily on getting a reliable release out on time rather than collating and writing notes for functionality they may not be familiar with.

[ianlancetaylor]

Your stance is entirely reasonable. Still, I hold to my position: by all means encourage writing release notes where appropriate, but don't require them.

[andybons]

I’d say we should strongly encourage writing release notes, taking into account the circumstances, of course. Right now it’s the exception. I’d like to move it more toward the norm, especially for long-time contributors.

[bcmills]

It also doesn't seem onerous to ask contributors who are +2'ing and merging a CL without a core team member involved to file an issue for someone else to follow up with documentation.

That's only a bit more overhead than making a RELNOTE= comment, and would only affect well-established contributors who presumably have an interest in the health of the project anyway.

[bcmills]

Actually, could GopherBot open an issue as soon as the CL is merged? That might combine the best of both workflows...

[bcmills]

(See previously #26419 (comment).)

[dmitshur]

Yes, gopherbot can do that, but it'll have to take care not make the mistake of no longer finding an issue it previously created, and entering a loop where it starts creating issues non-stop. While it can be humorous at first, that would not be good.

I suggest filing a separate issue for that, since it's not a completely trivial task and it would be helpful to agree on a high-level approach first. Writing the code to implement it should be easy.