public function assertRegionButton($button, $region)
    {
        $regionObj = $this->getRegion($region);

        $buttonObj = $regionObj->findButton($button);
        if (empty($buttonObj)) {
            throw new \Exception(sprintf("The button '%s' was not found in the region '%s' on the page %s", $button, $region, $this->getSession()->getCurrentUrl()));
        }
    }