<form method="POST">
    <h3>Editing: EmailCount.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Mailer\Test\Constraint;

use PHPUnit\Framework\Constraint\Constraint;
use Symfony\Component\Mailer\Event\MessageEvents;

final class EmailCount extends Constraint
{
    private int $expectedValue;
    private ?string $transport;
    private bool $queued;

    public function __construct(int $expectedValue, string $transport = null, bool $queued = false)
    {
        $this-&gt;expectedValue = $expectedValue;
        $this-&gt;transport = $transport;
        $this-&gt;queued = $queued;
    }

    public function toString(): string
    {
        return sprintf('%shas %s &quot;%d&quot; emails', $this-&gt;transport ? $this-&gt;transport.' ' : '', $this-&gt;queued ? 'queued' : 'sent', $this-&gt;expectedValue);
    }

    /**
     * @param MessageEvents $events
     */
    protected function matches($events): bool
    {
        return $this-&gt;expectedValue === $this-&gt;countEmails($events);
    }

    /**
     * @param MessageEvents $events
     */
    protected function failureDescription($events): string
    {
        return sprintf('the Transport %s (%d %s)', $this-&gt;toString(), $this-&gt;countEmails($events), $this-&gt;queued ? 'queued' : 'sent');
    }

    private function countEmails(MessageEvents $events): int
    {
        $count = 0;
        foreach ($events-&gt;getEvents($this-&gt;transport) as $event) {
            if (
                ($this-&gt;queued &amp;&amp; $event-&gt;isQueued())
                ||
                (!$this-&gt;queued &amp;&amp; !$event-&gt;isQueued())
            ) {
                ++$count;
            }
        }

        return $count;
    }
}
</textarea><br>
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