Symfony\Component\Form\Extension\DataCollector\FormDataCollector::recursiveBuildPreliminaryFormTree PHP Method

    private function &recursiveBuildPreliminaryFormTree(FormInterface $form, array &$outputByHash)
    {
        $hash = spl_object_hash($form);

        $output = &$outputByHash[$hash];
        $output = isset($this->dataByForm[$hash])
            ? $this->dataByForm[$hash]
            : array();

        $output['children'] = array();

        foreach ($form as $name => $child) {
            $output['children'][$name] = &$this->recursiveBuildPreliminaryFormTree($child, $outputByHash);
        }

        return $output;
    }