protected function getCaseNodes(): array
    {
        $caseNodes = $this->xml->xpath('//testcase');
        $cases = [];
        foreach ($caseNodes as $node) {
            $case = $node;
            if (!isset($cases[(string) $node['file']])) {
                $cases[(string) $node['file']] = [];
            }
            $cases[(string) $node['file']][] = $node;
        }

        return $cases;
    }