public function testDelTag()
{
$db = Zend_Registry::get('db');
$new_tag_id = Zend_Registry::get('new_tag_id');
$new_note_id = Zend_Registry::get('new_note_id');
$tag_name = Zend_Registry::get('tag_name');
$note = new Database_Notes($db);
$note->load($new_note_id);
//删除由之前单元中创建个tag
$note->delTag($tag_name);
//reload,以确保刚才的删除正常
$note->load($new_note_id);
$my_tags = $note->getJoinRow('tag');
$tag_is_gone = in_array($new_tag_id, $my_tags);
$this->assertFalse($tag_is_gone);
}