Re: refspecs with '*' as part of pattern
- From
- Daniel Barkalow <barkalow@iabervon.iabervon.org>
- Date
- Jul 7, 2015, 02:20 UTC
- Message-ID
- <alpine.LNX.2.00.1507062208580.2241@iabervon.iabervon.org>
- In-Reply-To
- <xmqqzj38yjpg.fsf@gitster.dls.corp.google.com>
On Mon, 6 Jul 2015, Junio C Hamano wrote:
Show 31 quoted lines
> Jacob Keller <jacob.keller@gmail.com> writes:
>
> > I've been looking at the refspecs for git fetch, and noticed that
> > globs are partially supported. I wanted to use something like:
> >
> > refs/tags/some-prefix-*:refs/tags/some-prefix-*
> >
> > as a refspec, so that I can fetch only tags which have a specific
> > prefix. I know that I could use namespaces to separate tags, but
> > unfortunately, I am unable to fix the tag format. The specific
> > repository in question is also generating several tags which are not
> > relevant to me, in formats that are not really useful for human
> > consumption. I am also not able to fix this less than useful practice.
> >
> > However, I noticed that refspecs only support * as a single component.
> > The match algorithm works perfectly fine, as documented in
> > abd2bde78bd9 ("Support '*' in the middle of a refspec")
> >
> > What is the reason for not allowing slightly more arbitrary
> > expressions? Obviously no more than one *...
>
> I cannot seem to be able to find related discussions around that
> patch, so this is only my guess, but I suspect that this is to
> discourage people from doing something like:
>
> refs/tags/*:refs/tags/foo-*
>
> which would open can of worms (e.g. imagine you fetch with that
> pathspec and then push with refs/tags/*:refs/tags/* back there;
> would you now get foo-v1.0.0 and foo-foo-v1.0.0 for their v1.0.0
> tag?) we'd prefer not having to worry about.That wouldn't be it, since refs/tags/*:refs/tags/foo/* would have the same problem, assuming you didn't set up the push refspec carefully.
I think it was mostly that it would be too easy to accidentally do something you don't want by having some other character instead of a slash, like refs/heads/*:refs/heads-*.
Aside from the increased risk of hard-to-spot typos leading to very weird behavior, nothing actually goes wrong; in fact, I've been using git with that check removed for ages because I wanted a refspec like refs/heads/something-*:refs/heads/*. And it works fine as a local patch, since you don't need your refspec handling to interoperate with other repositories.
-Daniel *This .sig left intentionally blank*