Syntax for the latest tag?

[wlandau]

This is a continuation from #200 (comment). I am posting here because I realized "*release" only applies to GitHub.

Would it be possible for the ref parameter to support syntax for the latest Git tag, whether the repo is hosted on GitHub, GitLab, Bitbucket, etc.? This would make it much easier to create tag-based package repositories on R-universe (if I correctly understand @jeroen's advice from r-universe-org/help#378).

@shikokuchuo, @llrs and I are working on R-releases, a new project that began in the R Consortium Repositories Working Group. We have lofty ambitions to curate Git releases across the entire R package ecosystem in one central R-universe, but we are finding that many maintainers create Git tags without GitHub releases, and that makes things difficult for us.

[wlandau]

I'm not actually sure how feasible tags are for the purposes of R-releases, c.f. r-multiverse/help#26 (comment).

[wlandau]

In R-releases, if we do decide to continue to track releases, then #570 would help a lot.

[wlandau]

The possibility of tags in non-default branches makes the concept of a "latest" tag tricky and even misleading if we are trying to get a release (c.f. r-multiverse/help#26 (comment)). So I no longer think a "latest tag" syntax would add value.