public function processMultiplePaths($paths)
    {
        $paths = $this->parseAsArray($paths);
        $paths = array_map([ $this, 'filterPath' ], $paths);
        $paths = array_filter($paths, [ $this, 'pathExists' ]);

        if ($paths === false) {
            throw new InvalidArgumentException('Received invalid paths.');
        }

        if (empty($paths)) {
            throw new InvalidArgumentException('Received empty paths.');
        }

        return $paths;
    }