git-svn: avoid importing nested git repos

Some SVN repositories contain git repositories within them
(hopefully accidentally checked in).  Since git refuses to track
nested ".git" repositories, this can be a problem when fetching
updates from SVN.

Thanks to Morgan Christiansson for the report and testing.

Signed-off-by: Eric Wong <normalperson@yhbt.net>

git-svn.perl

@@ -3291,6 +3291,11 @@ sub _mark_empty_symlinks {
 	\%ret;
 }
 
+# returns true if a given path is inside a ".git" directory
+sub in_dot_git {
+	$_[0] =~ m{(?:^|/)\.git(?:/|$)};
+}
+
 sub set_path_strip {
 	my ($self, $path) = @_;
 	$self->{path_strip} = qr/^\Q$path\E(\/|$)/ if length $path;
@@ -3316,6 +3321,7 @@ sub git_path {
 
 sub delete_entry {
 	my ($self, $path, $rev, $pb) = @_;
+	return undef if in_dot_git($path);
 
 	my $gpath = $self->git_path($path);
 	return undef if ($gpath eq '');
@@ -3343,8 +3349,12 @@ sub delete_entry {
 
 sub open_file {
 	my ($self, $path, $pb, $rev) = @_;
+	my ($mode, $blob);
+
+	goto out if in_dot_git($path);
+
 	my $gpath = $self->git_path($path);
-	my ($mode, $blob) = (command('ls-tree', $self->{c}, '--', $gpath)
+	($mode, $blob) = (command('ls-tree', $self->{c}, '--', $gpath)
 	                     =~ /^(\d{6}) blob ([a-f\d]{40})\t/);
 	unless (defined $mode && defined $blob) {
 		die "$path was not found in commit $self->{c} (r$rev)\n";
@@ -3352,20 +3362,27 @@ sub open_file {
 	if ($mode eq '100644' && $self->{empty_symlinks}->{$path}) {
 		$mode = '120000';
 	}
+out:
 	{ path => $path, mode_a => $mode, mode_b => $mode, blob => $blob,
 	  pool => SVN::Pool->new, action => 'M' };
 }
 
 sub add_file {
 	my ($self, $path, $pb, $cp_path, $cp_rev) = @_;
-	my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#);
+	my $mode;
-	delete $self->{empty}->{$dir};
+
-	{ path => $path, mode_a => 100644, mode_b => 100644,
+	if (!in_dot_git($path)) {
+		my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#);
+		delete $self->{empty}->{$dir};
+		$mode = '100644';
+	}
+	{ path => $path, mode_a => $mode, mode_b => $mode,
 	  pool => SVN::Pool->new, action => 'A' };
 }
 
 sub add_directory {
 	my ($self, $path, $cp_path, $cp_rev) = @_;
+	goto out if in_dot_git($path);
 	my $gpath = $self->git_path($path);
 	if ($gpath eq '') {
 		my ($ls, $ctx) = command_output_pipe(qw/ls-tree
@@ -3383,11 +3400,13 @@ sub add_directory {
 	my ($dir, $file) = ($path =~ m#^(.*?)/?([^/]+)$#);
 	delete $self->{empty}->{$dir};
 	$self->{empty}->{$path} = 1;
+out:
 	{ path => $path };
 }
 
 sub change_dir_prop {
 	my ($self, $db, $prop, $value) = @_;
+	return undef if in_dot_git($db->{path});
 	$self->{dir_prop}->{$db->{path}} ||= {};
 	$self->{dir_prop}->{$db->{path}}->{$prop} = $value;
 	undef;
@@ -3395,6 +3414,7 @@ sub change_dir_prop {
 
 sub absent_directory {
 	my ($self, $path, $pb) = @_;
+	return undef if in_dot_git($pb->{path});
 	$self->{absent_dir}->{$pb->{path}} ||= [];
 	push @{$self->{absent_dir}->{$pb->{path}}}, $path;
 	undef;
@@ -3402,6 +3422,7 @@ sub absent_directory {
 
 sub absent_file {
 	my ($self, $path, $pb) = @_;
+	return undef if in_dot_git($pb->{path});
 	$self->{absent_file}->{$pb->{path}} ||= [];
 	push @{$self->{absent_file}->{$pb->{path}}}, $path;
 	undef;
@@ -3409,6 +3430,7 @@ sub absent_file {
 
 sub change_file_prop {
 	my ($self, $fb, $prop, $value) = @_;
+	return undef if in_dot_git($fb->{path});
 	if ($prop eq 'svn:executable') {
 		if ($fb->{mode_b} != 120000) {
 			$fb->{mode_b} = defined $value ? 100755 : 100644;
@@ -3424,11 +3446,13 @@ sub change_file_prop {
 
 sub apply_textdelta {
 	my ($self, $fb, $exp) = @_;
+	return undef if (in_dot_git($fb->{path}));
 	my $fh = $::_repository->temp_acquire('svn_delta');
 	# $fh gets auto-closed() by SVN::TxDelta::apply(),
 	# (but $base does not,) so dup() it for reading in close_file
 	open my $dup, '<&', $fh or croak $!;
 	my $base = $::_repository->temp_acquire('git_blob');
+
 	if ($fb->{blob}) {
 		my ($base_is_link, $size);
 
@@ -3469,6 +3493,8 @@ sub apply_textdelta {
 
 sub close_file {
 	my ($self, $fb, $exp) = @_;
+	return undef if (in_dot_git($fb->{path}));
+
 	my $hash;
 	my $path = $self->git_path($fb->{path});
 	if (my $fh = $fb->{fh}) {

t/t9133-git-svn-nested-git-repo.sh

@@ -0,0 +1,101 @@
+#!/bin/sh
+#
+# Copyright (c) 2009 Eric Wong
+#
+
+test_description='git svn property tests'
+. ./lib-git-svn.sh
+
+test_expect_success 'setup repo with a git repo inside it' '
+	svn co "$svnrepo" s &&
+	(
+		cd s &&
+		git init &&
+		test -f .git/HEAD &&
+		> .git/a &&
+		echo a > a &&
+		svn add .git a &&
+		svn commit -m "create a nested git repo" &&
+		svn up &&
+		echo hi >> .git/a &&
+		svn commit -m "modify .git/a" &&
+		svn up
+	)
+'
+
+test_expect_success 'clone an SVN repo containing a git repo' '
+	git svn clone "$svnrepo" g &&
+	echo a > expect &&
+	test_cmp expect g/a
+'
+
+test_expect_success 'SVN-side change outside of .git' '
+	(
+		cd s &&
+		echo b >> a &&
+		svn commit -m "SVN-side change outside of .git" &&
+		svn up &&
+		svn log -v | fgrep "SVN-side change outside of .git"
+	)
+'
+
+test_expect_success 'update git svn-cloned repo' '
+	(
+		cd g &&
+		git svn rebase &&
+		echo a > expect &&
+		echo b >> expect &&
+		test_cmp a expect &&
+		rm expect
+	)
+'
+
+test_expect_success 'SVN-side change inside of .git' '
+	(
+		cd s &&
+		git add a &&
+		git commit -m "add a inside an SVN repo" &&
+		git log &&
+		svn add --force .git &&
+		svn commit -m "SVN-side change inside of .git" &&
+		svn up &&
+		svn log -v | fgrep "SVN-side change inside of .git"
+	)
+'
+
+test_expect_success 'update git svn-cloned repo' '
+	(
+		cd g &&
+		git svn rebase &&
+		echo a > expect &&
+		echo b >> expect &&
+		test_cmp a expect &&
+		rm expect
+	)
+'
+
+test_expect_success 'SVN-side change in and out of .git' '
+	(
+		cd s &&
+		echo c >> a &&
+		git add a &&
+		git commit -m "add a inside an SVN repo" &&
+		svn commit -m "SVN-side change in and out of .git" &&
+		svn up &&
+		svn log -v | fgrep "SVN-side change in and out of .git"
+	)
+'
+
+test_expect_success 'update git svn-cloned repo again' '
+	(
+		cd g &&
+		git svn rebase &&
+		echo a > expect &&
+		echo b >> expect &&
+		echo c >> expect &&
+		test_cmp a expect &&
+		rm expect
+	)
+'
+
+test_done