Re: [PATCH 3/4] set_work_tree: use chdir_notify

[Jeff King <peff@peff.net>]

On Thu, Mar 29, 2018 at 07:02:21PM +0200, Duy Nguyen wrote:

> On Wed, Mar 28, 2018 at 7:42 PM, Jeff King <peff@peff.net> wrote:
> > When we change to the top of the working tree, we manually
> > re-adjust $GIT_DIR and call set_git_dir() again, in order to
> > update any relative git-dir we'd compute earlier.
> 
> Another way to approach this problem is not delaying chdir() at all.
> We have to delay calling setup_work_tree() and not do it in
> setup_git_directory() because it can die() when chdir() fails. But in
> many cases, the command does not actually need the worktree and does
> not deserve to die. But what if we make setup_work_tree be gentle?
> 
> If it successfully chdir() at the end of setup_git_directory() (and
> perhaps before the first set_git_dir call), great! The problem we're
> dealing here vanishes. If it fails, don't die, just set a flag. Later
> on when a command requests a worktree, we can check this flag and now
> can die().
> 
> It's less code this way, but it uses up more of your (or my) time
> because even though the first set_git_dir() call actually happens at 8
> places. Is it worth trying ?

I do kind of like that. I'm reasonably happy with the chdir_notify()
interface, but it would be nicer still if we could get rid of it in the
first place. It's true that we _could_ chdir from other places, but
realistically speaking, we do our one big chdir as part of the setup
process.

-Peff