public function testAdd()
 {
     $filename = dirname(__FILE__) . DIRECTORY_SEPARATOR . 'tempfile';
     $container = new MW_Container_PHPExcel($filename, 'Excel5', array());
     $container->add($container->create('test'));
     $result = 0;
     foreach ($container as $content) {
         $result++;
     }
     $container->close();
     unlink($container->getName());
     $this->assertEquals(1, $result);
 }