git push "$(pwd)/xxx${pathsep}yyy.git" HEAD
'
+test_expect_success 'updating a ref from quarantine is forbidden' '
+ git init --bare update.git &&
+ write_script update.git/hooks/pre-receive <<-\EOF &&
+ read old new refname
+ git update-ref refs/heads/unrelated $new
+ exit 1
+ EOF
+ test_must_fail git push update.git HEAD &&
+ git -C update.git fsck
+'
+
test_done