#!/bin/bash

# This script checks whether two input files have a diff.
#
# Usage:
#
#   check-no-diff <first file> <second file>
#
# If there is no diff, the script exits with a zero success status.
# If there is a diff, the script prints the diff to stdout and exits with a
# non-zero error status.

tmpdiff=$(mktemp)
diff --left-column -y $1 $2 > $tmpdiff \
       && echo OK || (cat $tmpdiff; false)
status=$?

rm $tmpdiff
exit $status