Re: [PATCH] git rev-parse: Fix --show-cdup inside symlinked directory

On Tue, 2008-07-15 at 17:40 +0200, Petr Baudis wrote:

  no, no, this is for the scenario other way around: you have a normal
subdirectory in the working tree, and point a symlink _at_ it from
$somewhere_else. Then you try to work in $somewhere_else/symlink.

Yes correct. We have a number of different repositories like so:

banana.git/apps
banana.git/lib
orange.git/config
kiwi.git/refdata

and its convenient for many of our existing apps to be able to symlink
them all together into a common tree

joined/apps -> banana.git/apps
joined/lib -> banana.git/lib
joined/config -> orange.git/config
joined/refdata -> kiwi.git/refdata

this way for instance we can swap bits around easily on the fly and say,
restart a webserver or whatever.

Currently we can do this and all our other stuff works, and you
can /mostly/ work with git from the "joined" tree, with the exception of
git pull --rebase and apparently anything else that relies on
--show-cdup

quoted

quoted

This patch changes --show-cdup to always show absolute workdir path
instead. I think this should hopefully cause no compatibility problems;
the testsuite is passing fine, at least.

See the thread where I proposed a change like this, back with the infamous 
worktree desaster, and Junio NACKed; or the thread where Linus rightfully 
insists that git_dir should be relative if possible, for performance 
reasons.

  I see, [ref]. But noone was aware
of this possible user case. Performance reasons sound reasonable, though
I'm not really sure if for cdup in particular this ever matters.

Would it be so bad to detect if the show-cdup actually resolves to the
right place, and if it doesnt go absolute?

  P.S.: Either way, there is a possible workaround to tell git about the
working directory manually using git --work-tree=... that I missed to
mention on IRC, Yves.

Hmm, am i using it wrong then?

[dmq@somewhere apps]$ git-rev-parse --git-dir
/home/dmq/git_tree/main/.git
[dmq@somewhere apps]$ git --work-tree="$(git-rev-parse --git-dir)" pull
--rebase
/usr/bin/git-sh-setup: line 139: cd: .git: No such file or directory
Unable to determine absolute path of git directory

cheers,
yves
ps: not on list, please cc me on replies (sorry for the hassle)