Re: merging unmanaged working tree

From: Avery Pennarun <apenwarr@gmail.com>
Date: Mar 15, 2010, 23:49 UTC
Message-ID: <32541b131003151649v1a1265f1ke3ccac9cc930f9c8@mail.gmail.com>
In-Reply-To: <87eijlw4cn.fsf@kotik.lan>

2010/3/15 Łukasz Stelmach <lukasz.stelmach@iem.pw.edu.pl>:

Show 10 quoted lines

> Avery Pennarun <apenwarr@gmail.com> writes:
>> a) Look at 'git clone --depth' so you can clone only the most recent
>> version of the files, not the *entire* repo.  This lets you do commits
>> on any computer you want with the pen drive plugged in, but saves
>> space.
>
> I've tried this one. It works (but why the --depht 1 gives two
> revisions?) but even thoug the main repository and the portable one have
> common commits I can't pull changes back from the mobile to the main
> one. Is there any wise trick to make git try a little harder?

I don't know; I haven't used shallow clones (ie. --depth) very much. git's implementation of them seems a bit half-hearted. The man page says "A shallow repository has a number of limitations (you cannot clone or fetch from it, nor push from nor into it), but is adequate if you are only interested in the recent history of a large project with a long history, and would want to send in fixes as patches." There is no technical reason for this limitation, as far as I know.

It does give a hint as to what you could do instead of push/pulling, however: you could use git format-patch to extract the changes from your shallow copy, and git am to import the patches back into your main copy. Seems like a pain though.

Show 12 quoted lines

>> b) Keep your .git directory on your main PC's disk, and the working
>> tree on your pen drive.  Look at the GIT_DIR environment variable in
>> 'man git'.  Then when you bring the pen drive back to your PC, you
>> have the full repo available.  (If you use 'git clone --reference'
>> when making the new repo, the extra .git directory should take only
>> minimal space.)
>
> This one's nice and seems to be most space efficient as far as flash
> space is concerned. However, I'd be able to sync only with the machine
> that holds the portable GIT_DIR while the previous method, if only
> there was a way to make git work with shallow clones, could work with
> different hosts if I synec my No1 desktop with them too.

Maybe you could do something like:

      git clone -s ~/myrepo /pendrive/myrepo

This will give you a .git dir in /pendrive/myrepo, but all the *objects* in the git repo will actually be borrowed from ~/myrepo. This will make git virtually unusable on /pendrive/myrepo *unless* you mount the disk on a PC that has ~/myrepo in the original location. On any such computer, you could be able to do normal git operations in /pendrive/myrepo, including pulling changes from there to ~/myrepo.

As you do git operations on /pendrive, /pendrive/myrepo/.git will slowly accumulate objects that you might have to clear out over time (ie. after pushing them to the parent repo).

Show 6 quoted lines

> I've just invented yet another method. Push the content to the pendrive:
>
> $ git commit -am branching
> $ git archive --format tar HEAD | tar -C /media/pendrive/project -xf -
> $ git log -1 > /media/pendrive/project/HEAD # to remember
> [...]

Yeah, I guess you could do that, but at that point you're basically not using git anymore.

Have fun,

Avery