use strict;
use warnings;
use 5.010;
use autodie;

open my $fh1, '<', 'file1';
open my $fh2, '<', 'file2';

while (my $test1 = <$fh1>, my $test2 = <$fh2>) {
    chomp($test1 //= '');
    chomp($test2 //= '');
    say "$test1, $test2";
}