[RFC PATCH] git-svn: proper detection of bare repositories

[Deskin Miller <deskinm@umich.edu>]

I keep coming across commands like this, which don't work properly in bare
repositories, and thinking that they need to be patched (see e.g. ddff8563, or
Duy's comments on the thread starting at
http://thread.gmane.org/gmane.comp.version-control.git/98849), but now I'm not
so sure.  For one, despite this patch working, it turns out that 'git --bare
svn <cmd>' also works (and presumably has) for some time.

Is git --bare the correct way to deal with this situation?  That is to say, do
we intend commands to 'just work' regardless of whether the repo is bare or
not, or should the user be thinking about the difference and including --bare
in the command invocation when necessary?  I'm a vote for the 'just work' camp,
but it seems a lot of things aren't necessarily that way.  On the other hand,
the majority of commands do just work.

I guess I'm asking for a sanity check before I write any more such patches;
certainly I find them useful, as the issues come up during my normal use of
Git, but I don't want to be pursuing things of no use to anyone else, or
(worse) things that are fundamentally wrong for some reason I don't understand
yet.

-- 8< --

When in a bare repository (or .git, for that matter), git-svn would fail
to initialise properly, since git rev-parse --show-cdup would not output
anything.  However, git rev-parse --show-cdup actually returns an error
code if it's really not in a git directory.

Fix the issue by checking for an explicit error from git rev-parse, and
setting $git_dir appropriately if instead it just does not output.

Signed-off-by: Deskin Miller <deskinm@umich.edu>
---
 git-svn.perl             |   14 ++++++++++----
 t/t9100-git-svn-basic.sh |    9 +++++++++
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/git-svn.perl b/git-svn.perl
index 56238da..d25e9be 100755
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -42,6 +42,7 @@ use File::Path qw/mkpath/;
 use Getopt::Long qw/:config gnu_getopt no_ignore_case auto_abbrev/;
 use IPC::Open3;
 use Git;
+use Error qw/:try/;
 
 BEGIN {
 	# import functions from Git into our packages, en masse
@@ -214,11 +215,16 @@ unless ($cmd && $cmd =~ /(?:clone|init|multi-init)$/) {
 			    "but it is not a directory\n";
 		}
 		my $git_dir = delete $ENV{GIT_DIR};
-		chomp(my $cdup = command_oneline(qw/rev-parse --show-cdup/));
-		unless (length $cdup) {
-			die "Already at toplevel, but $git_dir ",
-			    "not found '$cdup'\n";
-		}
+		my $cdup = undef;
+		try {
+			$cdup = command_oneline(qw/rev-parse --show-cdup/);
+			$git_dir = '.' unless ($cdup);
+			chomp $cdup if ($cdup);
+			$cdup = "." unless ($cdup && length $cdup);
+		}
+		catch Git::Error::Command with {
+			die "Already at toplevel, but $git_dir not found\n";
+		};
 		chdir $cdup or die "Unable to chdir up to '$cdup'\n";
 		unless (-d $git_dir) {
 			die "$git_dir still not found after going to ",
diff --git a/t/t9100-git-svn-basic.sh b/t/t9100-git-svn-basic.sh
index 843a501..fdbc23a 100755
--- a/t/t9100-git-svn-basic.sh
+++ b/t/t9100-git-svn-basic.sh
@@ -265,4 +265,13 @@ test_expect_success 'able to set-tree to a subdirectory' "
 	test -z \"\`git diff refs/heads/my-bar refs/remotes/bar\`\"
 	"
 
+test_expect_success 'git-svn works in a bare repository' '
+	mkdir bare-repo &&
+	( cd bare-repo &&
+	git init --bare &&
+	GIT_DIR=. git svn init "$svnrepo" &&
+	git svn fetch ) &&
+	rm -rf bare-repo
+	'
+
 test_done
-- 
1.6.0.3.524.g47d14