protected function addSpeakingURLParameterNode()
    {
        $builder = new TreeBuilder();
        $node = $builder->root('speakingurl');

        $node
           ->treatTrueLike(array('path' => '%kernel.root_dir%/../vendor/pid/speakingurl/speakingurl.min.js'))
           ->treatFalseLike(array('path' => false))
           ->treatNullLike(array('path' => false))
           ->children()
               ->scalarNode('path')
                   ->cannotBeEmpty()
                   ->defaultValue('%kernel.root_dir%/../vendor/pid/speakingurl/speakingurl.min.js')
               ->end()
           ->end()
        ;

        return $node;
    }