From: Jeff King <peff@peff.net>
Date: Thu, 07 Feb 2008 05:13:18 GMT
Subject: Re: [PATCH] allow setting GIT_WORK_TREE to "no work tree"
Message-ID: <20080207051317.GA32296@sigill.intra.peff.net>
In-Reply-To: <7vwsphu7gr.fsf@gitster.siamese.dyndns.org>

On Wed, Feb 06, 2008 at 12:59:32PM -0800, Junio C Hamano wrote:

> I do not like the magic GIT_WORK_TREE=: which is simply
> illogical.  GIT_EDITOR=: made perfect sense (":" is actually a
> command that succeeds without doing anything), but ":" does not
> have anything to do with "there is no such path".

No, it doesn't, but they are both no-ops. Sort of. I agree the reasoning
is stretched, but I think we are just going to have to choose _some_
arbitrary value.

Unless you want to switch it to a "git set GIT_DIR automatically,
so don't pretend the user set it" flag variable.

> I was tempted to suggest GIT_WORK_TREE=/dev/null because that is
> what "diff" uses to mark "this does not even exist", but that
> feels dirty.

It feels dirty to me, too. I would rather choose something that doesn't
even look like a path. I think GIT_WORK_TREE=" " is too ugly, too.

Also, having just looked at the '.git-file' code, it does the same thing
(setting GIT_DIR even though the user didn't explicitly ask for it), so
it will need a similar fix. Which makes me lean towards just setting a
"we set this behind the user's back" flag, since that code won't even
have anything to do with the worktree.

In fact, the more I think about it, that makes sense. WORK_TREE munging
just happens to be the only special behavior right now that depends on
whether the user manually set GIT_DIR. But what we really want to
communicate to later code is not "I have corrected this particular
munge" but "don't run any special behavior as a result of this variable
being set."

-Peff