gistfile1.txt

use strict;
use warnings;

use Test::More tests => 1;
use Plack::Test;

$Plack::Test::Impl = 'AnyEvent';

test_psgi $app, sub {
    my ( $cb ) = @_; 

    my $res = $cb->(GET '/changes.json');
    is $res->header('Transfer-Encoding'), 'chunked';
    is $res->content_type, 'application/json';
    is $res->body, ''; 
    $res->on_body_received(sub {
        my ( $chunk ) = @_; 

        ## do something with $chunk
        if($done) {
            $res->send;
        }   
    }); 
    $res->recv;
};