public function testLastBackupsIdentical()
 {
     $meta = $this->getMeta(123123123123.0);
     $this->fs->getSize('s77_mail_2015-04-22.tar.gz')->willReturn($meta);
     $this->fs->getSize('s77_mail_2015-04-21.tar.gz')->willReturn($meta);
     $result = $this->assert->assertBackups(new \DateTime('2015-04-22'));
     $this->assertEquals("Laatste twee e-mail backups zijn even groot.", $result);
 }
<?php

namespace root;

use Frlnc\Slack\Core\Commander;
use Frlnc\Slack\Http\CurlInteractor;
use Frlnc\Slack\Http\SlackResponseFactory;
use League\Flysystem\Filesystem;
use League\Flysystem\Adapter\Ftp;
require 'vendor/autoload.php';
require 'Assert.php';
$config = (include 'config.php');
function report($message)
{
    global $config;
    $interactor = new CurlInteractor();
    $interactor->setResponseFactory(new SlackResponseFactory());
    $commander = new Commander($config['slack'], $interactor);
    $commander->execute('chat.postMessage', ['username' => 'Backup validator', 'icon_emoji' => ':x:', 'channel' => '#server', 'text' => $message]);
}
$filesystem = new Filesystem(new Ftp($config['ftp']));
$assert = new Assert($filesystem);
$result = $assert->assertBackups(new \DateTime());
if ($result !== true) {
    report('Waarschuwing: ' . $result);
}