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

From: Duy Nguyen <pclouds@gmail.com>
Date: Mar 29, 2018, 17:02 UTC
Message-ID: <CACsJy8CAjb4zdAgD5H9OZOAoHdrRFzGm9gaL8Wbna+GXJJCW4Q@mail.gmail.com>
In-Reply-To: <20180328174215.GC16274@sigill.intra.peff.net>

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 ?

-- 
Duy