Re: [QUESTION] Tracking HEAD changes?

From: Jeff King <peff@peff.net>
Date: Feb 23, 2021, 00:38 UTC
Message-ID: <YDROhhrM5qJti1ir@coredump.intra.peff.net>
In-Reply-To: <CAGgn8PdU1GE_CZdGUpJWKzygd0O+Yn2BnAFGmPfKAxFpoVoqUA@mail.gmail.com>

On Mon, Feb 22, 2021 at 11:12:11AM +0200, Yaron Wittenstein wrote:

Show 7 quoted lines

> Is there any possible way to track changes to HEAD using hooks?
> 
> Being able to listen using hooks to events such as pre-head-checkout
> and post-head-checkout would be the best option (from my perspective).
> 
> To my knowledge, the only possible way to do that today is by adding a
> file watch over the refs directory.

No, I don't think there is currently a better way.

If you do go the file watch route, make sure you put one on HEAD, too (to catch the case of checking out a different branch, as opposed to updating it with a new commit). I use:

  gitdir=$(git rev-parse --git-dir)
  # We need delete_self to pick up changes to HEAD (since it gets renamed
  # over), and "move" to pick up changes in the refs directories.
  inotifywait -qq -t 60 -e delete_self -e move -r "$gitdir/HEAD" "$gitdir/refs"

in a script that I use for automatically running tests against the current commit. (if you are doing something similar, I also recommend https://github.com/mhagger/git-test for avoiding re-running against the same commits repeatedly).

-Peff