[PATCH for comments] configure: install a whitespace checking pre-commit hook for developers

[Jeremy Allison]

On Tue, Apr 10, 2018 at 12:35:07AM +1200, Douglas Bagnall via samba-technical wrote:
> Martin wrote:
> 
> > The problem is that the *initial* proposal is not for a checkpatch
> > script that people can run *before* submitting their patch.  The
> > proposal is for something that runs at the submission gate.
> 
> This patch shows a third way, still quite authoritarian but sort of
> opt-out-able and entirely local. It makes it harder to *create*
> patches that break the rules, not to submit them.
> 
> It will also (I think) make it harder to `git am` a patch series that
> contains whitespace errors, and will possibly annoy people who make a
> lot of private WIP patches.

Thanks very much Douglas, this looks like it might be a great
solution that works for all ! Thanks very much for helping out
with this contentious issue.

I'll test it out and push if happy.

Cheers,

	Jeremy.

> From 126836d41d4154594805890557fbbb9f7d0ac04b Mon Sep 17 00:00:00 2001
> From: Douglas Bagnall <douglas.bagnall at catalyst.net.nz>
> Date: Tue, 10 Apr 2018 00:03:55 +1200
> Subject: [PATCH] configure: install a whitespace checking pre-commit hook for
>  developers
> 
> If you don't already have a pre-commit git hook,
> 
>   configure --enable-developer
> 
> will give you one that checks for whitespace errors in changed lines
> of Python, Perl and C.
> 
> Signed-off-by: Douglas Bagnall <douglas.bagnall at catalyst.net.nz>
> ---
>  examples/git-hooks/pre-commit | 15 +++++++++++++++
>  wscript                       |  9 ++++++++-
>  2 files changed, 23 insertions(+), 1 deletion(-)
>  create mode 100755 examples/git-hooks/pre-commit
> 
> diff --git a/examples/git-hooks/pre-commit b/examples/git-hooks/pre-commit
> new file mode 100755
> index 00000000000..68c6150cde6
> --- /dev/null
> +++ b/examples/git-hooks/pre-commit
> @@ -0,0 +1,15 @@
> +#!/bin/sh
> +
> +git diff-index --check  HEAD -- :/*.[ch] :/*.p[ylm]
> +
> +if [ $? != 0 ]; then
> +    echo
> +    echo "The commit failed because it seems to introduce trailing whitespace"
> +    echo "into C, Perl, or Python code."
> +    echo
> +    echo "If you are sure you want to do this, repeat the commit with the "
> +    echo "--no-verify, like this:"
> +    echo
> +    echo "   git commit --no-verify"
> +    exit 1
> +fi
> diff --git a/wscript b/wscript
> index 0985aa94867..102b772428b 100644
> --- a/wscript
> +++ b/wscript
> @@ -10,7 +10,7 @@ import sys, os, tempfile
>  sys.path.insert(0, srcdir+"/buildtools/wafsamba")
>  import wafsamba, Options, samba_dist, samba_git, Scripting, Utils, samba_version
>  import Logs, samba_utils
> -
> +import shutil
>  
>  samba_dist.DIST_DIRS('.')
>  samba_dist.DIST_BLACKLIST('.gitignore .bzrignore source4/selftest/provisions')
> @@ -105,6 +105,13 @@ def configure(conf):
>      if Options.options.developer:
>          conf.ADD_CFLAGS('-DDEVELOPER -DDEBUG_PASSWORD')
>          conf.env.DEVELOPER = True
> +        # if we are in a git tree without a pre-commit hook, install a
> +        # simple default. 
> +        pre_commit_hook = os.path.join(srcdir, '.git/hooks/pre-commit')
> +        if (os.path.isdir(os.path.dirname(pre_commit_hook)) and
> +            not os.path.exists(pre_commit_hook)):
> +            shutil.copy(os.path.join(srcdir, 'examples/git-hooks/pre-commit'),
> +                        pre_commit_hook)
>  
>      conf.ADD_EXTRA_INCLUDES('#include/public #source4 #lib #source4/lib #source4/include #include #lib/replace')
>  
> -- 
> 2.11.0
>