Re: [PATCH 1/3] Accept root <tree-ish> in 'git-svn commit-diff'

[Eric Wong <normalperson@yhbt.net>]

Sergey Yanovich <ynvich@gmail.com> wrote:
> Experiments with Subversion (my version is 1.4.2) show that it is
> not necessary to call 'svn import' before the first commit. Contrarily
> to the Subversion documentation, first commit may be done even when
> Subversion repository is at revision 0.
> 
> This allow export the whole git branch to a Subversion repo using only
> 'git-svn commit-diff'. Before this patch, however, 'git-svn' had
> no means to operate on root commits.

Cool.

> Signed-off-by: Sergey Yanovich <ynvich@gmail.com>
> ---
>  git-svn.perl |    9 ++++++++-
>  1 files changed, 8 insertions(+), 1 deletions(-)
> 
> diff --git a/git-svn.perl b/git-svn.perl
> index 50128d7..8ad291b 100755
> --- a/git-svn.perl
> +++ b/git-svn.perl
> @@ -2572,7 +2572,12 @@ sub generate_diff {
>  	}
>  	push @diff_tree, '--find-copies-harder' if $_find_copies_harder;
>  	push @diff_tree, "-l$_rename_limit" if defined $_rename_limit;
> -	push @diff_tree, $tree_a, $tree_b;
> +	if ($tree_a eq '0000000000000000000000000000000000000000') {

You can make this more legible by using '0' x40 instead of repeating
40 '0' characters.  Also, it might be a good idea to support --root
directly for git-svn so the user won't have to type 40 zeroes in the
command-line :)

> +		push @diff_tree, '--root';
> +	} else {
> +		push @diff_tree, $tree_a;
> +	}
> +	push @diff_tree, $tree_b;
>  	my ($diff_fh, $ctx) = command_output_pipe(@diff_tree);
>  	local $/ = "\0";
>  	my $state = 'meta';
> @@ -2606,6 +2611,8 @@ sub generate_diff {
>  			}
>  			$x->{file_b} = $_;
>  			$state = 'meta';
> +		} elsif ($state eq 'meta' && $_ eq $tree_b &&
> +			$tree_a eq '0000000000000000000000000000000000000000') {

Same here with '0' x40

>  		} else {
>  			croak "Error parsing $_\n";
>  		}
> -- 
> 1.5.2.1
> 

-- 
Eric Wong