I've got a Web site heavily spiked with tutorials and sample code. The tutorial programs are very simple, and the user interaction is not what you'd consider demanding.

Given a simple Parrot PIR program like this:

.sub 'main' :main
    .local string name
    .local string greeting
    .local pmc stdin

    stdin = getstdin
    name = stdin.'readline_interactive'("Please enter your name: ")
    greeting = "Hello, " . name
    greeting .= "!" 
    say greeting
.end
[download]

The sample usage is straightforward, but bothersome to double-check every time I update my Parrot install.

$ parrot code/example-01-06.pir
Please enter your name: Brian
Hello, Brian!

Manually verifying behavior after a language update has become tiresome. So I wrote some tests. They use IO::Pty::Easy to handle input and output.

use Modern::Perl;
use IO::Pty::Easy;
use Test::More tests => 3;

my $pty = IO::Pty::Easy->new;
ok $pty->spawn("parrot", "code/example-01-06.pir");

my $output = $pty->read();
is $output, "Please enter your name: ";

$pty->write("Brian\n");
$output = $pty->read();
is $output, "Hello, Brian!\n";

$pty->close;
[download]

There's nothing wrong with this code - at least nothing that is obvious to me. I'm just wondering if there is a test approach or IO library preferred by the monks for testing lots of simple scripts of this nature.

Edit: Added the Parrot script being tested to hopefully improve the coherence of my late night post.