public function delete_topic($topic_id)
{
$this->add_lang('posting');
$crawler = $this->get_quickmod_page($topic_id, 'DELETE_TOPIC');
$this->assertContainsLang('DELETE_PERMANENTLY', $crawler->text());
$this->add_lang('mcp');
$form = $crawler->selectButton('Yes')->form();
$form['delete_permanent'] = 1;
$crawler = self::submit($form);
$this->assertContainsLang('TOPIC_DELETED_SUCCESS', $crawler->text());
}