Unnamed

#!/usr/bin/perl
use warnings;
use strict;

@ARGV == 1 or die "$0 exe\n";

my @tests = `ls testfiles`;

for my $test (@tests) {
        chomp $test;
        system("$ARGV[0] < testfiles/$test > output/$test");
        my $diff = `diff expected/${test}_output output/$test`;
        if ($?) {
                print "$test\n";
                system("cat testfiles/$test");
                print "Expected: \n";
                system("cat expected/${test}_output");
                print "Output: \n";
                system("cat output/$test");
                exit;
        }
}