git-submodule.sh: fix '/././' path normalization

When we add a new submodule the path of the submodule is being
normalized. We fail to normalize multiple adjacent '/./', though.
Thus 'path/to/././submodule' will become 'path/to/./submodule' where
it should be 'path/to/submodule' instead.
Signed-off-by: NPatrick Steinhardt <ps@pks.im>
Acked-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

git-submodule.sh

@@ -420,7 +420,7 @@ cmd_add()
 		sed -e '
 			s|//*|/|g
 			s|^\(\./\)*||
-			s|/\./|/|g
+			s|/\(\./\)*|/|g
 			:start
 			s|\([^/]*\)/\.\./||
 			tstart

t/t7400-submodule-basic.sh

@@ -171,6 +171,23 @@ test_expect_success 'submodule add with ./ in path' '
 	test_cmp empty untracked
 '
 
+test_expect_success 'submodule add with /././ in path' '
+	echo "refs/heads/master" >expect &&
+	>empty &&
+
+	(
+		cd addtest &&
+		git submodule add "$submodurl" dotslashdotsubmod/././frotz/./ &&
+		git submodule init
+	) &&
+
+	rm -f heads head untracked &&
+	inspect addtest/dotslashdotsubmod/frotz ../../.. &&
+	test_cmp expect heads &&
+	test_cmp expect head &&
+	test_cmp empty untracked
+'
+
 test_expect_success 'submodule add with // in path' '
 	echo "refs/heads/master" >expect &&
 	>empty &&