Renaming a package with only lower-/upper-case changes does not work

[countvajhula]

Re: this email thread, I wanted to change a package name from Titlecase to lowercase. This didn't work, but renaming it to a different name and then back to the lowercase version did work. E.g.:

This works:

Mypackage -> Mypackage-temp -> mypackage

But not

Mypackage -> mypackage

As Tony pointed out in the email thread, it likely prevents the direct rename because the new name conflicts with "an existing" package (i.e. itself).

Also, last time I checked (which could have been months ago), raco pkg install <pkgname> did not find the package unless the Titlecase name was used, and likewise in info.rkt, the Titlecase name was needed to indicate the dependency or it would not be found. Since names differing only in case are considered equivalent for the purposes of uniqueness, should this not perhaps also hold for raco and info.rkt? i.e. raco pkg install should tolerate case variation to install the unique package that such varying names could refer to (whatever the "preserved" case of that package name may be).

For reference, this is the package that was renamed: https://pkgd.racket-lang.org/pkgn/package/relation

[mflatt]

We're stuck between a rock and a hard place here. On the one hand, case-insensitive package and collection names create a world of trouble, because many different parts of the system would have to include a normalization support that's easy to forget or get wrong (or, worse, a combination of normalization plus case preservation). On the other hand, some filesystems are case-insensitive, and we rely in many places on a correspondence between package/collection names and filesystem entities.

It would have been a good idea to disallow uppercase letters in package and collection names in the first place. But we didn't. That left us in the situation where uppercase letters are sometimes used, and people who stay on case-sensitive filesystems sometimes take advantage of the distinction.

In reaction to this mismatch, we added a check to the package server to disallow multiple packages in the same catalog with the same name after case folding. That at least reduces the chance that people will create packages that conflict on installations with case-insensitive paths. It also more or less allows the pkg-build service to run on a case-insensitive filesystem (which it did until recently).

The package server could be smarter about allowing a package to be renamed in a way that only changes its case. Adjusting everything to treat package and collection names in a case-insensitive way, though, would be difficult.

[racket-discourse-github-bot]

This issue has been mentioned on Racket Discussions. There might be relevant details there:

https://racket.discourse.group/t/package-seems-not-to-be-updated/874/4