Re: Syntax check via update hook?

[Mark Plaksin <happy@usg.edu>]

Jeff King <peff@peff.net> writes:

> On Tue, May 12, 2009 at 03:16:50PM -0400, Mark Plaksin wrote:
>
>> >         $ cat <<EOF >.git/hooks/update
>> >         #!/bin/sh
>> >         GIT_INDEX_FILE=/path/to/tempdir/index; export GIT_INDEX_FILE
>> >         cd /path/to/tempdir/tree &&
>> >         mkdir -p tree &&
>> >         git read-tree "$3" &&
>> >         git checkout-index &&
>> >         your_syntax_check
>> >         EOF
>> >         $ chmod +x .git/hooks/update
>> 
>> Thanks for helping! :)
>> 
>> Unfortunately we don't quite get it.  Can you flesh out your example a
>> bit and explain the concepts involved?  We're relative git newbies.  We
>> tried reading the man pages to the commands you use to no avail.  One
>> big stumbling block seems to be how we create/set-up tempdir.  Is that
>> supposed to be a pre-created git checkout, or created via git-archive,
>> or .. ?
>
> What I was trying to say earlier is that you have two choices based on
> how efficient you want to make it. The simple way is to use git-archive:

OK, this makes sense now.  Thanks for being patient with us :)

> However, all of that being said, if you just want:
>
>> Also, we actually just want to check the syntax of the files that were
>> changed in the commit, not the whole tree.  Will your method give us
>> access to the path names of the files that changed?
>
> That is simpler, especially if you can feed the files to your
> syntax-checker over stdin. You just need to enumerate the files, and
> then ask git to dump each one:

...

> Make sense?

It does!  You make it seem so easy!  Thanks very much.  I now have an
update hook which checks syntax just like we want.  Thanks again!