#!/bin/sh

while read oldrev newrev refname ; do
	if expr "$oldrev" : '0*$' >/dev/null ; then
		exit 0
	fi

	if [ "$refname" != "refs/heads/stable" ] ; then
		exit 0
	fi

	# read backwards:
	# - all commits from old..new
	# - unless they were already pointed to by a branch
	# - unless that branch is us
	# = all new commits on stable
	count=$(git rev-parse --not --branches | grep -v $(git rev-parse $refname) | git rev-list --stdin $oldrev..$newrev | wc -l)
	if [ "$count" -ne "0" ] ; then
		newname=$(git rev-parse "$newrev")
		echo "----------------------------------------------------"
		echo
		echo "Moving stable to $newname includes a new commit"
		echo
		echo "----------------------------------------------------"
		exit 1
	fi
done