On Thu, Aug 12, 2021 at 01:48:00PM -0700, Junio C Hamano wrote: > > Emily Shaffer <emilyshaffer@xxxxxxxxxx> writes: > > > Teach the hook.[hc] library to parse configs to populare the list of > > hooks to run for a given event. > > > > Multiple commands can be specified for a given hook by providing > > multiple "hook.<friendly-name>.command = <path-to-hook>" and > > "hook.<friendly-name>.event = <hook-event>" lines. Hooks will be run in > > config order of the "hook.<name>.event" lines. > > > > For example: > > > > $ git config --list | grep ^hook > > hook.bar.command=~/bar.sh > > hook.bar.event=pre-commit > > Your answer might be "read the design doc", but it is unclear to me > why "bar" (friendly-name) is needed in this picture at all. Is it > because you may want to fire more than one command for pre-commit > event? IOW, > > [hook "bar"] > command = bar1.sh > command = bar2.sh > event = pre-commit > > is easier to manage with an extra level of redirection? I doubt it > as > > [hook "pre-commit"] > command = bar1.sh > command = bar2.sh > > would be equally expressive and shorter. Or would it help use case > for multiple "friendly-name" to refer to the same "event", e.g. > > [hook "xyzzy"] > event = pre-commit > command = xyzzy1 > > [hook "frotz"] > event = pre-commit > command = frotz1 > command = frotz2 > > or something? I am not sure if this gives us useful extra > flexibility, and if so, the extra flexibility helps us more than it > confuses us. > > And moving the "event" to the second level in the configuration > hierarchy, getting rid of "friendly-name" from the design, would not > make this example unworkable, either: > > > $ git hook run > > # Runs ~/bar.sh > > # Runs .git/hooks/pre-commit > > Again, this is not an objection wrapped in a rhetorical question. > It just is that I do not see how the extra level of redirection > helps us. Please have a look at https://lore.kernel.org/git/87fswey5wd.fsf%40evledraar.gmail.com and replies, where Ævar and I discussed the schema change at length. I know it is a lot of back and forth but I think it is useful to understand why I ended up changing the schema this way. > > > diff --git a/Documentation/config/hook.txt b/Documentation/config/hook.txt > > index 96d3d6572c..a97b980cca 100644 > > --- a/Documentation/config/hook.txt > > +++ b/Documentation/config/hook.txt > > @@ -1,3 +1,8 @@ > > +hook.<command>.command:: > > + A command to execute during the <command> hook event. This can be an > > + executable on your device, a oneliner for your shell, or the name of a > > + hookcmd. See linkgit:git-hook[1]. > > Please make sure you use the terminology consistently. If the > second level is "friendly name", hook.<name>.command should be > described, instead of hook.<command>.command. Thanks, this is an oversight. Will update the config/hook.txt doc in next reroll. > > Also, to help those who are familiar with the current Git from their > use in the past 10 years or so, giving an example name from the > current system may help, e.g. when describing hook.<name>.event, > you may want to say the values are things like "pre-commit", > "receive", etc. Sure. > > > +This command parses the default configuration files for pairs of configs like > > +so: > > + > > + [hook "linter"] > > + event = pre-commit > > + command = ~/bin/linter --c > > The above addition of .command should also have hook.<name>.event > next to it, no? I don't understand the question. Doesn't this config snippet equate to """ hook.linter.event=pre-commit hook.linter.command=~/bin/linter --c """ ? So in this case, '<name>' is 'linter', as that's not a native Git hook. > > > +Conmmands are run in the order Git encounters their associated > > "Conmmands -> Commands", I would think. ACK > > > +`hook.<name>.event` configs during the configuration parse (see > > +linkgit:git-config[1]). > > Here you use <name>, which should be matched by the description in > the first hunk of the patch to this file. Yep. > > > +In general, when instructions suggest adding a script to > > +`.git/hooks/<hook-event>`, you can specify it in the config instead by running > > +`git config --add hook.<some-name>.command <path-to-script> && git config --add > > +hook.<some-name>.event <hook-event>` - this way you can share the script between > > +multiple repos. That is, `cp ~/my-script.sh ~/project/.git/hooks/pre-commit` > > +would become `git config --add hook.my-script.command ~/my-script.sh && git > > +config --add hook.my-script.event pre-commit`. > > One repository may use a friendly name "xyzzy" while the other may > use "frotz" to group the hooks that trigger upon "pre-commit" event, > but unless one of the repositories change the friendly name to > match, they cannot share these configurations, no? It seems that an > extra level of indirection is hindering sharing, rather than > helping. Ah, I think this means the documentation isn't sufficient, if you are asking that. Instead of explaining it in ephemeral email, I think it is better for me to explain it in documentation reroll, and for you to then tell me how you interpret it. I expect to send the reroll before I go home today, since I didn't receive comments from anybody besides you so far. Thanks very much for the feedback on the doc - this is very useful. - Emily
