Treat tilde versions as higher for purpose of dependency comparison

[ignatenkobrain]

In Rust packaging we've found issue that we have Requires: (foo >= 1.0.0 with foo < 2.0.0) and package with version 2.0.0~alpha is actually is matching this range. I think it should be treated for dependency check purpose.

/cc @ffesti

[pmatilai]

Err, no. If its sorts lower than 2.0.0 then it must match the < 2.0.0 dependency, anything else would be a mess that nobody will understand.

How exactly is this a problem for you?

[pmatilai]

To rephrase a bit, I can see why you'd sometimes want 2.0.0~alpha to be considered 2.0.0, but also that in other cases not, and rpm cannot magically know which one you want for a particular case. It'd be nice if there was a way to explicitly express both cases.

This sort of reminds me of this (otherwise unrelated) case: http://lists.rpm.org/pipermail/rpm-maint/2010-November/002948.html

[ffesti]

I guess there is no real way around using Requires: (foo >= 1.0.0 with foo < 2.0.0~). Yes, this is kinda annoying.

[ignatenkobrain]

@pmatilai yeah, this is somewhat similar. Unfortunately I don't know how we could nicely express both.

@ffesti yeah, the only problem is that semver.org says you can have versions like 2.0.0----beta which would be translated into 2.0.0~~~~beta in RPM. Not saying it is horrible or people should be doing this, but this case is valid. Also this tilde at the end looks not really nice :/ Especially if people would have to read this in their error messages.

[pmatilai]

So what's the actual use-case here? Converting upstream dependency tracking data to rpm?

[ignatenkobrain]

For this specific one is to be used in %autosetup and some more places in spec. Because default %name-%version doesn't work for pre-release packages.

[ignatenkobrain]

whoops, wrong ticlket. For this one is yes -- converting upstream dependency data into the RPM one... which works fine except for this small thingy.

[jasontibbitts]

Since what you really want is a significantly different total ordering, you really need a different set of binary relations. I certainly don't want to be the one to propose <~, <=~, >~, and >=~. Plus, for completeness, I guess you'd need a comparison operator =~. That would all be... horrible.
Personally I'd take the 99% solution and use the with foo < 2.0.0~ syntax; if the set of cases where we care ever overlaps the set of cases where someone uses the multiple tilde thing then someone will just have to handle the case by hand.

[ffesti]

As pointed out by @jasontibbitts we really don't want to go down this rabbit whole. I am closing this - even if this is not great. Sorry!