Nette tester. Random url generate

i´m using mrtnzlml/testbench and i wanna try one of my formular. BUT problem is here ... after succesfully formular send i wanna be redirect to Homepage:default with some flash messange, but nette generates url like ?_fid=sad, so how i can write this into my test? when this url is random??? I tries somethink like this:

$this->checkForm('Article:create', 'createArticleForm', $this->articleData(), '/[a-zA-Z0-9=?_+]');

but it doesn´t work. Can you pls tell me how to test my form?