public function testStorageIsImmutableOnceDeviceIsRetrieved() { $config = $this->config; $userAgent = new Zend_Http_UserAgent($config); $device = $userAgent->getDevice(); $this->setExpectedException('Zend_Http_UserAgent_Exception', 'immutable'); $userAgent->setStorage(new Zend_Http_UserAgent_Storage_NonPersistent()); }