wernermisc/bin/purge

#!/bin/sh
if [ "$1" ]; then
    cd "$1" || exit
fi
git ls-files -m | grep '.pro$' |
    while read n; do
	if ! [ "`git diff "$n" |
	  sed '/^--- /d;/^+++ /d;/^[^-+]/d;/^.update=/d'`" ]; then
	    echo purging "$n" 1>&2
	    git checkout "$n"
	fi
    done