private function deleteSubfolder($path, $params)
    {
        // Use a key that adds a trailing slash if needed.
        $prefix = rtrim($params['Key'], '/') . '/';
        $result = $this->getClient()->listObjects([
            'Bucket'  => $params['Bucket'],
            'Prefix'  => $prefix,
            'MaxKeys' => 1
        ]);

        // Check if the bucket contains keys other than the placeholder
        if ($contents = $result['Contents']) {
            return (count($contents) > 1 || $contents[0]['Key'] != $prefix)
                ? $this->triggerError('Subfolder is not empty')
                : $this->unlink(rtrim($path, '/') . '/');
        }

        return $result['CommonPrefixes']
            ? $this->triggerError('Subfolder contains nested folders')
            : true;
    }