From: Marco Costalba <mcostalba@gmail.com>
Date: Sun, 04 Jun 2006 10:42:16 GMT
Subject: Re: Gitk feature - show nearby tags
Message-ID: <e5bfff550606040342q5e485ae2lcc00e36ed405be8c@mail.gmail.com>
In-Reply-To: <e5bfff550606040333h1180bbep88fa90ea9928d062@mail.gmail.com>

On 6/4/06, Marco Costalba <mcostalba@gmail.com> wrote:
> On 6/4/06, Junio C Hamano <junkio@cox.net> wrote:
> > "Marco Costalba" <mcostalba@gmail.com> writes:
> >
> > > In a less corner case, just to better explaing my idea, consider this:
> > >
> > >          a---b---d---e---f---g---h
> > >          t1   \ /              t3
> > >             ---c
> > >                t2
> > >
> > > Where our sha1 is still "e", in this case
> > >
> > > git-rev-list  --topo-order <e>  ^a  ^c   ^g
> > >
> > > gives, as last revision in output list, "f"
> > > Then parentOf(<f>) is <g> and our looked for tag is t3
> >
> > Sorry, in the example time flows from left to right.  If you
> > exclude g then you are excluding everything that is reachable
> > from g so you would not see "f".

To better explain what I mean, that's the algorithm :

cmd = "git-rev-list --topo-order --parents " + sha;
for (uint i = 0; i < tagList.count(); i++)
	cmd.append(" ^" + tagList[i]);

output = run(cmd);

if (output.isEmpty()) {
	parent = parentOf(sha);
	return (parent && parent->isTag()) ? parent->tag() : NO_TAG;
}

lastSha = getLastLine(output);
parent = parentOf(lastSha);
return (parent && parent->isTag()) ? parent->tag() : NO_TAG;