#!/usr/bin/perl

use strict;
use warnings;
use Test::More 'no_plan';

sub dargv {
    local *ARGV;
    @ARGV = @_;
    <>;
}

sub dopen {
    map {
        open my $fh, '<', $_ or warn "Can't open `$_': $!\n";
        <$fh>;
    } @_;
}

while (<>) {
    chomp;
    is_deeply [dargv $_], [dopen $_] => $_;
}

__END__