if head_=$(git symbolic-ref -q HEAD); then
case "$head_" in
refs/heads/*)
- git rev-parse -q --verify "${head_#refs/heads/#refs/top-bases#}" >/dev/null || exit 0;;
+ git rev-parse -q --verify "refs/top-bases${head_#refs/heads}" >/dev/null || exit 0;;
*)
exit 0;;
esac