Re: [PATCH 8/9 v13] difftool: teach difftool to handle directory diffs

From: David Aguilar <davvid@gmail.com>
To: Tim Henigan <tim.henigan@gmail.com>
Cc: gitster@pobox.com, git@vger.kernel.org, ramsay@ramsay1.demon.co.uk
Subject: Re: [PATCH 8/9 v13] difftool: teach difftool to handle directory diffs
Date: Sun, 15 Apr 2012 18:01:06 -0700	[thread overview]
Message-ID: <CAJDDKr78T1HNFXPPnvMUxBoJhAHP8XGdk9ZbpQCS1sZEQJfR8w@mail.gmail.com> (raw)
In-Reply-To: <CAJDDKr7Uw3Nwg4p7F2zaY8f82j3_tRf3WiiO+YSN+nA6a9wY6w@mail.gmail.com>

On Sun, Apr 15, 2012 at 3:20 PM, David Aguilar <davvid@gmail.com> wrote:
> On Fri, Apr 13, 2012 at 9:36 AM, Tim Henigan <tim.henigan@gmail.com> wrote:
>> When 'difftool' is called to compare a range of commits that modify
>> more than one file, it opens a separate instance of the diff tool for
>> each file that changed.
>>
>> The new '--dir-diff' option copies all the modified files to a temporary
>> location and runs a directory diff on them in a single instance of the
>> diff tool.
>>
>> Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
>> ---
>>
>> This replaces v12 of the script that was sent to the list on April 12, 2011.
>>
>> Changes in v13:
>>
>> The 'git diff' command is now called via 'Git->repository->command_oneline'
>> again. We need to run the command in a way that allows @ARGV to be given
>> as a list, rather than a string, to insure that IFS and shell meta-
>> characters are handled properly.  Thanks to Junio Hamano for pointing
>> this out [1].
>>
>> [1]: http://thread.gmane.org/gmane.comp.version-control.git/195326/focus=195353
>
> Thanks Tim.  Sorry for reading this patch out of context and missing
> the obvious point that it needs the diff output to do something useful
> in my last review.
>
> I started testing this patch.  I started on the commit before what's
> in pu and then applied this patch:
>
> $ git checkout e9653615fafcbac6109da99fac4fa66b0b432048
> $ git am difftool.patch
>
> The basics work and I know folks will be really happy when this
> feature lands.  Folks have personally asked me for this feature in the
> past.  I dig it.  I'd also like to help pursue using symlinks sometime
> in the future if that sounds like a reasonable thing to you, but the
> stabilizing the existing implementation is more important right now.
>
> I ran into some issues when trying it against a few random commits.  I
> went pretty far back in git's history to see what would happen.
>
> $ git difftool --dir-diff e5b06629de847663aaf0f7daae8de81338da3901 | tail
> Use of uninitialized value $rmode in string eq at
> /home/david/src/git/git-difftool line 96.

I did some more investigating.  I think this happens when the diff
contains detected renames.

This command made it work:

$ git difftool --dir-diff --no-renames e5b06629de847663aaf0f7daae8de81338da3901

So I think we might need to specify --no-renames when calling git diff --raw.

xxdiff still gives an error message about "$tmp/left/RelNotes: No such
file or directory" with --no-renames so we may want to touch some
dummy files to make the tools happy.
-- 
David