/**
  * Prepares the environment before running a test
  * 
  */
 protected function setUp()
 {
     // read navigation config
     $this->_files = dirname(__FILE__) . '/_files/navigation';
     $config = new Zend_Config_Xml($this->_files . '/navigation.xml');
     // create nav structures
     $this->_nav1 = new Zym_Navigation($config->get('nav_test1'));
     $this->_nav2 = new Zym_Navigation($config->get('nav_test2'));
     // create view
     $view = new Zend_View();
     $view->addHelperPath('Zym/View/Helper', 'Zym_View_Helper');
     // create helper
     $this->_helper = new $this->_helperName();
     $this->_helper->setView($view);
     // set nav1 in helper as default
     $this->_helper->setNavigation($this->_nav1);
 }
 /**
  * Sets default ACL role(s) to use when iterating pages if not explicitly
  * set later with {@link setRole()}
  * 
  * @param  null|string|Zend_Acl_Role_Interface $role   [optional] role to set,
  *                                                     defaults to null
  * @throws InvalidArgumentException  if $role is not null, string, or
  *                                   Zend_Acl_Role_Interface
  * @return void
  */
 public static function setDefaultRole($role = null)
 {
     if (null === $role || is_string($role) || $role instanceof Zend_Acl_Role_Interface) {
         self::$_defaultRole = $role;
     } else {
         $msg = '$role must be null|string|Zend_Acl_Role_Interface';
         throw new InvalidArgumentException($msg);
     }
 }