Re: StGit hooks

Karl Hasselström [off-list ref] writes:

On 2007-11-28 18:06:36 +0100, Andreas Ericsson wrote:

quoted

True, but there are ways of figuring out which branch you're on,
using the arguments passed to the hook.

The rebase hook (which is where this discussion started) gets the
branches passed to "git rebase" as arguments. Figuring out if either
of those branches are actually under stgit control shouldn't be
overly tricky for one so familiar with stgit as yourself.

No, that part is trivial. The hard part is not messing up the user's
existing hook scripts.

If I do go ahead and do this, I have a feeling I'll be beefing up
git's hook dispatch mechanism first -- if I can get it past Junio,
obviously. :-)

I do not see a fundamental problem in a scheme like this:

 * when running a hook $foo, if .git/hooks/$foo.d/. does not exist, we
   operate as we have always done.

 * if .git/hooks/$foo.d/ exists, we readdir(3) it and run the hooks found
   in the order their names sort bytewise (similar to /etc/rc$n.d/).

   - when the purpose of the $foo hook is to return a bool to refuse an
     operation, stop at the first failure;

   - when the purpose of the $foo hook is to cause effect, run them all
     in series.

 * When .git/hooks/$foo.d/ exists, there will always be "050-simple" in
   that directory.  It checks if .git/hooks/$foo exists and sources it
   if it does.  A custom hook that wants to run before or after it can
   be named NNN-mine in .git/hooks/$foo.d/, where NNN sorts earlier or
   later than 050 to define the execution order.

We probably would want to reserve a special exit code for the hooks run
for their effects so that they can signal "I do not want you to run the
remainder".