Re: [PATCH v2 6/7] config: allow configuration of multiple hook error behavior

From: brian m. carlson <sandals@crustytoothpaste.net>
Date: May 15, 2019, 23:10 UTC
Message-ID: <20190515231017.GM7458@genre.crustytoothpaste.net>
In-Reply-To: <CACsJy8BN32Jm62MQPLsRwKST8DDNZ7NxnJbsqBO3PJ0K2qU-Ng@mail.gmail.com>

On Tue, May 14, 2019 at 08:20:10PM +0700, Duy Nguyen wrote:

Show 9 quoted lines

> On Tue, May 14, 2019 at 7:24 AM brian m. carlson
> <sandals@crustytoothpaste.net> wrote:
> >
> > There are a variety of situations in which a user may want an error
> > behavior for multiple hooks other than the default. Add a config option,
> > hook.<name>.errorBehavior to allow users to customize this behavior on a
> 
> An alternative name is onError, probably more often used for event
> callbacks. But I don't know, maybe errorBehavior is actually better.

I'm going to use "errorStrategy", since we already have submodule.alternateErrorStrategy.

> > per-hook basis. Provide options for the default behavior (exiting
> 
> should we fall back to hook.errorBehavior? That allows people to set
> global policy, then customize just a small set of weird hooks.

Sure, that sounds good.

Show 9 quoted lines

> maybe stop-on-first-error (or if you go with the "onError" name, I
> think "stop" is enough). I know "stop on/after first hook" does not
> really make any sense when you think about it. Maybe stop-on-first is
> sufficient.
> 
> I was going to suggest strcasecmp. But core.whitespace (also has
> multiple-word-values) already sets a precedent on strcmp. I think
> we're good. Or mostly good, I don't know, we still accept False, false
> and FALSE.

I think with errorStrategy, "stop" is fine. Simpler is better.

I literally picked what Peff had suggested in his email (mostly because I'm terrible at naming things), and I don't get the impression he spent a great deal of time analyzing the ins and outs of the names before sending. I could be wrong, though.

Show 8 quoted lines

> > +                       behavior = HOOK_ERROR_STOP_ON_FIRST;
> 
> This is basically the logical "and" behavior in a C expression. Which
> makes me think if anybody's crazy enough to need the "or" counterpart
> (i.e. run hooks, expect failure, keep going until the first success).
> 
> I guess it's a crazy mode. We should not care about until a real use
> case shows up.

Yeah, I think that's unlikely to be the case. Nothing prevents us from adding it later.

Show 5 quoted lines

> > +               else if (!strcmp(value, "report-any-error"))
> 
> I couldn't guess based on this name alone, whether we continue or stop
> after the reporting part. The 7/7 document makes it clear though. So
> all good.

I'm open to hearing better suggestions if anyone has any.

Show 13 quoted lines

> > diff --git a/run-command.c b/run-command.c
> > index 191d6f6f7e..70fb19a55b 100644
> > --- a/run-command.c
> > +++ b/run-command.c
> > @@ -1308,6 +1308,8 @@ int async_with_fork(void)
> >  #endif
> >  }
> >
> > +struct string_list hook_error_behavior = STRING_LIST_INIT_NODUP;
> 
> Maybe stick this in 'struct repository'. I know most config variables
> are still global. But I think we have to move/reorganize them at some
> point. Most may end up in 'struct repository'.

Okay, sounds fine.

> > +                       default:
> > +                               BUG("unknown hook error behavior");
> 
> maybe BUG(".. behavior %d", behavior);

Sure.

-- 
brian m. carlson: Houston, Texas, US
OpenPGP: https://keybase.io/bk2204