Re: [PATCH/RFC] git-svn: don't create master if another head exists

[Marcin Owsiany <marcin@owsiany.pl>]

On Sun, Jun 24, 2012 at 10:44:57PM -0700, Junio C Hamano wrote:
> Marcin Owsiany <marcin@owsiany.pl> writes:
> 
> > git-svn insists on creating the "master" head (unless it exists) on every
> > "fetch". While it is useful that it gets created initially (users expect this
> > git convention), some users find it annoying that it gets recreated, especially
> > when they would like the git branch names to follow SVN repository branch
> > names. More background in
> > http://thread.gmane.org/gmane.comp.version-control.git/115030
> >
> > Make git-svn skip the "master" creation if there is another head ref pointing
> > to the same place. This means "master" does get created on initial "clone" but
> > does not get recreated once a user deletes it.
> >
> > Signed-off-by: Marcin Owsiany <marcin@owsiany.pl>
> > ---
> >  git-svn.perl |    2 ++
> >  1 files changed, 2 insertions(+), 0 deletions(-)
> >
> > diff --git a/git-svn.perl b/git-svn.perl
> > index 0b074c4..90f3d06 100755
> > --- a/git-svn.perl
> > +++ b/git-svn.perl
> > @@ -1613,6 +1613,8 @@ sub post_fetch_checkout {
> >  	}
> >  
> >  	my $valid_head = verify_ref('HEAD^0');
> > +	my @heads_commits = eval { command(qw(show-ref --heads --hash)) };
> > +	return if $valid_head and grep { $_ eq $valid_head } @heads_commits;
> 
> This is strange.  Much earlier in the code there is this use of
> master.
> 
>     sub post_fetch_checkout {
>             return if $_no_checkout;
>             my $gs = $Git::SVN::_head or return;
>             return if verify_ref('refs/heads/master^0');
> 
> If your goal is to get rid of "master" (because you have a different
> branch that serves the role of the primary branch), shouldn't this
> code be killed?  Otherwise, if you have a stray "master" that you
> are not even using, you would end up skipping checkout for your true
> primary branch, no?

This is my first attempt at modifying git code and I don't pretend to
understand everything this function does. Even less obvious to me is why
it does that. E.g. "return if ($valid_head || ..." - skips the checkout
if HEAD was pointing at tip of _any_ branch, right? But why?

So I'm just trying to change as little as possible.

-- 
Marcin Owsiany <marcin@owsiany.pl>              http://marcin.owsiany.pl/
GnuPG: 2048R/02F946FC  35E9 1344 9F77 5F43 13DD  6423 DBF4 80C6 02F9 46FC

"Every program in development at MIT expands until it can read mail."
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