Don't try and percent-escape existing percent escapes in git-svn URIs

git-svn project names are percent-escaped ever since f5530b8
(git-svn: support for funky branch and project names over HTTP(S),
2007-11-11).

Unfortunately this breaks the scenario where the user hands git-svn an
already-escaped URI.  Fix the regexp to skip over what looks like
existing percent escapes, and test this scenario.

Signed-off-by: Kevin Ballard <kevin@sb.org>
Acked-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-svn.perl

@@ -3665,7 +3665,7 @@ sub escape_uri_only {
 	my ($uri) = @_;
 	my @tmp;
 	foreach (split m{/}, $uri) {
-		s/([^\w.-])/sprintf("%%%02X",ord($1))/eg;
+		s/([^\w.%-]|%(?![a-fA-F0-9]{2}))/sprintf("%%%02X",ord($1))/eg;
 		push @tmp, $_;
 	}
 	join('/', @tmp);

t/t9120-git-svn-clone-with-percent-escapes.sh

@@ -0,0 +1,31 @@
+#!/bin/sh
+#
+# Copyright (c) 2008 Kevin Ballard
+#
+
+test_description='git-svn clone with percent escapes'
+. ./lib-git-svn.sh
+
+test_expect_success 'setup svnrepo' "
+	mkdir project project/trunk project/branches project/tags &&
+	echo foo > project/trunk/foo &&
+	svn import -m '$test_description' project '$svnrepo/pr ject' &&
+	rm -rf project &&
+	start_httpd
+"
+
+if test "$SVN_HTTPD_PORT" = ""
+then
+	test_expect_failure 'test clone with percent escapes - needs SVN_HTTPD_PORT set' 'false'
+else
+	test_expect_success 'test clone with percent escapes' '
+		git svn clone "$svnrepo/pr%20ject" clone &&
+		cd clone &&
+			git rev-parse refs/remotes/git-svn &&
+		cd ..
+	'
+fi
+
+stop_httpd
+
+test_done