Re: [PATCH] push: Learn to set up branch tracking with '--track'

From: Jeff King <peff@peff.net>
Date: Jan 29, 2009, 22:33 UTC
Message-ID: <20090129223308.GB12871@coredump.intra.peff.net>
In-Reply-To: <alpine.DEB.1.00.0901291438030.3586@pacific.mpi-cbg.de>

On Thu, Jan 29, 2009 at 02:38:43PM +0100, Johannes Schindelin wrote:

Show 10 quoted lines

> When pushing a branch to a remote repository that the remote side did
> not know beforehand, it is often handy to set up the branch tracking
> such that
> 
> 	$ git checkout xyz
> 	$ git push --track origin xyz:abc
> 	$ git pull
> 
> will pull the branch 'abc' from the remote 'origin' into the branch
> 'xyz'.

What if "xyz" is a tag? Right now, the patch generates a bogus config section. Yes, you can say "don't use --track, then". But I can think two reasons why that isn't acceptable:

  1. You might be pushing multiple things, one of which is a branch
     and one of which is not.

  2. This is likely to grow a related config variable, similar to
     branch.autosetupmerge.

How about "git push --track origin HEAD"? This also generates bogus config. How about "git push --track origin refs/heads/*:refs/heads/*"? Also bogus.

It looks like you catch "git push --track --all". So at least there is no bogus config generated. But it would be nice to translate this to "create a tracking branch for everything I pushed".

So I think this patch is going about it the wrong way. Instead of parsing the refspec, I think you actually want to look at what we _do_ push (or at least try to push -- probably even uptodate refs should also have tracking established), and use that. Then you will have wildcards expanded, --all handled, etc. And I suspect all you have to do is iterate over the result of match_refs (which we call later), which should be even easier (because you don't have to parse the refspecs yourself). But I haven't looked carefully.

> +		if (!err && track)
> +			setup_tracking(transport->url);

Wouldn't the remote name (if we have one) be preferable to the URL? As it is, doing "git push --track origin master" results in

  [branch "master"]
    remote = $YOUR_URL_FOR_ORIGIN
    merge = refs/heads/master

which means that:

  1. If you ever change remote.origin.url, it will not propagate to your
     branch section.

  2. When you fetch, you are fetching into FETCH_HEAD, meaning your
     tracking refs are not updated.

-Peff