lib/Mailer/MailGun.php
protected function getFiles(MessageInterface $message)
    {
        if (!($message instanceof AttachmentsAwareInterface)) {
            return [];
        }

        // Process files
        list($attachments, $inline) = $this->processAttachments($message->getAttachments());

        // Format params
        $files = [];
        if ($attachments) {
            $files['attachment'] = $attachments;
        }
        if ($inline) {
            $files['inline'] = $inline;
        }

        return $files;
    }
protected function getFiles(MessageInterface $message)
    {
        if (!($message instanceof AttachmentsAwareInterface)) {
            return [];
        }

        // Process files
        list($attachments, $inline) = $this->processAttachments($message->getAttachments());

        // Format params
        $files = [];
        if ($attachments) {
            $files['attachment'] = $attachments;
        }
        if ($inline) {
            $files['inline'] = $inline;
        }

        return $files;
    }
{@inheritdoc}