function assertExtractStyleBlocks($html, $expect = true, $styles = array())
 {
     $filter = new HTMLPurifier_Filter_ExtractStyleBlocks();
     // disable cleaning
     if ($expect === true) {
         $expect = $html;
     }
     $this->config->set('Filter.ExtractStyleBlocks.TidyImpl', false);
     $result = $filter->preFilter($html, $this->config, $this->context);
     $this->assertIdentical($result, $expect);
     $this->assertIdentical($this->context->get('StyleBlocks'), $styles);
 }