[BUG] git-svn parses --pretty=medium log output, fails when log.decorate is true

> I started receiving this error during "git svn dcommit" today:
> 
> Use of uninitialized value $hash in string eq
> at /home/wpalmer/libexec/git-core/git-svn line 1534.
> 
> Examining that section reveals that git-svn is running 
> "git log --no-color --first-parent --pretty=medium"
> 
> and parsing the output in order to find commit hashes and git-svn-id:
> lines. This breaks when log.decorate is true.
> 
> This could be patched-up by adding "--no-decorate" to the options
> git-svn passes, but that seems to me like it would just be adding to the
> pile, as "--pretty=medium" is a moving target. I assume the correct
> solution is to specify the format exactly as it is expected.

> I started receiving this error during "git svn dcommit" today:
> 
> Use of uninitialized value $hash in string eq
> at /home/wpalmer/libexec/git-core/git-svn line 1534.
> 
> Examining that section reveals that git-svn is running 
> "git log --no-color --first-parent --pretty=medium"
> 
> and parsing the output in order to find commit hashes and git-svn-id:
> lines. This breaks when log.decorate is true.
> 
> This could be patched-up by adding "--no-decorate" to the options
> git-svn passes, but that seems to me like it would just be adding to the
> pile, as "--pretty=medium" is a moving target. I assume the correct
> solution is to specify the format exactly as it is expected.

> On Tue, Oct 05, 2010 at 11:18:46AM +0100, Will Palmer wrote:
> 
>> I started receiving this error during "git svn dcommit" today:
>>
>> Use of uninitialized value $hash in string eq
>> at /home/wpalmer/libexec/git-core/git-svn line 1534.
>>
>> Examining that section reveals that git-svn is running 
>> "git log --no-color --first-parent --pretty=medium"
>>
>> and parsing the output in order to find commit hashes and git-svn-id:
>> lines. This breaks when log.decorate is true.
>>
>> This could be patched-up by adding "--no-decorate" to the options
>> git-svn passes, but that seems to me like it would just be adding to the
>> pile, as "--pretty=medium" is a moving target. I assume the correct
>> solution is to specify the format exactly as it is expected.
> 
> The problem isn't necessarily --pretty=medium, but that we are using
> "git log" instead of "git rev-list" (though because "git log" does have
> some features that rev-list does not have, we do turn off most
> configurable features for "git log --pretty=raw").
> 
> So I think the simplest thing is just the patch below (which has only
> been lightly tested by me):
> 
> -- >8 --
> Subject: [PATCH] git-svn: use rev-list instead of log
> 
> We are parsing the output, so we don't want user
> configuration like color or decorations to appear in the
> output. The simplest way to accomplish this is to use the
> rev-list plumbing instead of the log porcelain.
> 
> Signed-off-by: Jeff King <peff@peff.net>
> ---
>  git-svn.perl |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/git-svn.perl b/git-svn.perl
> index d292224..03d93d8 100755
> --- a/git-svn.perl
> +++ b/git-svn.perl
> @@ -1514,7 +1514,7 @@ sub cmt_sha2rev_batch {
>  
>  sub working_head_info {
>  	my ($head, $refs) = @_;
> -	my @args = ('log', '--no-color', '--first-parent', '--pretty=medium');
> +	my @args = ('rev-list', '--first-parent', '--pretty=medium');
>  	my ($fh, $ctx) = command_output_pipe(@args, $head);
>  	my $hash;
>  	my %max;

> > --- a/git-svn.perl
> > +++ b/git-svn.perl
> > @@ -1514,7 +1514,7 @@ sub cmt_sha2rev_batch {
> >  
> >  sub working_head_info {
> >  	my ($head, $refs) = @_;
> > -	my @args = ('log', '--no-color', '--first-parent', '--pretty=medium');
> > +	my @args = ('rev-list', '--first-parent', '--pretty=medium');
> >  	my ($fh, $ctx) = command_output_pipe(@args, $head);
> >  	my $hash;
> >  	my %max;
> 
> You're right. Using rev-list looks like a much cleaner solution.
> 
> In addition, I think we can replace the call to git-log in git_svn_log_cmd() too.