On Tue, Mar 13, 2018 at 11:09 AM, Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> wrote: > > On Tue, Mar 13 2018, Michal Novotny jotted: > >> On Tue, Mar 13, 2018 at 10:07 AM, Ævar Arnfjörð Bjarmason >> <avarab@xxxxxxxxx> wrote: >>> >>> On Tue, Mar 13 2018, Michal Novotny jotted: >>> >>>> Hello, >>>> >>>> currently, if I try to create a tag that has tilde "~" in name, an >>>> error is raised. E.g. >>>> >>>> $ git tag rpkg-util-1.4~rc1 >>>> fatal: 'rpkg-util-1.4~rc1' is not a valid tag name. >>>> >>>> Now, actually it would be very cool if tilde was allowed in a tag name >>>> because we would like to use it for tagging pre-releases of (not-only >>>> rpm) packages. >>>> >>>> Is there some deep technical reason why tilde cannot be present in a >>>> tag name? I tried that e.g. >>> >>> Yes, because a trailing tilde is part of git's rev syntax, see "man >>> git-rev-parse", or try in any repo: >>> >>> git show HEAD >>> git show HEAD~2 >>> git show HEAD^~2 >> >> Right, reading the man pages: >> >> <rev>~<n>, e.g. master~3 >> A suffix ~<n> to a revision parameter means the commit >> object that is the <n>th generation ancestor of the named commit >> object, following only the first >> parents. I.e. <rev>~3 is equivalent to <rev>^^^ which is >> equivalent to <rev>^1^1^1. See below for an illustration of the usage >> of this form. >> >> Would it be acceptable to disallow only ~<n> (<n> as [0-9]+) in a tag >> name but allow ~[^0-9].*, i.e. if the immediately following symbol >> after '~' is a letter, do not >> interpret ~ as a special character. Could it work? > > We could make that work, with some caveats: > > 1) The syntax we've reserved for refnames is quite small, and my bias > at least would be to say you should just make a tag like > rpkg-util-1.4-rc1 instead (as e.g. git.git and linux.git do). There is kind of clash of symbolics with rpm world. In rpm world, the component after the last dash in a package full (versioned) name is usually reserved for a downstream packager who increments it as he/she adds patches to the original sources. I will need to do slightly more research here of what is possible. Thank you so far! > > Carving out an exception like this also means we couldn't use > ~[^0-9].* for anything magical in the future. > > But I think that's a rather small objection, we have other syntax > escape hatches, and we're unlikely to use ~[^0-9].* as some new > magic. > > 2) If we patch git to accept this, you'll be creating refs that aren't > inter-operable with previous versions of git. > > This is a big deal. E.g. you'll happily create this special ref, > then try to push it to github, and they'll croak because that's an > invalid ref to them. Ditto some co-worker of yours who's using an > older version of git. > > FWIW if you manually create such a tag e.g. for-each-ref will emit > 'warning: ignoring ref with broken name' and just not show it. > >>> >>> etc. >>> >>> Although I guess git could learn to disambiguate that form from the tag >>> you're trying to create. >>> >>>> git tag rpkg-util-1.4%rc1 >>>> >>>> but percentage sign does not seem to be particular fitting for >>>> pre-release marking. >>>> >>>> Thank you >>>> clime
