src/ExtraDataProcessor.php
private function appendExtraFields(array $extra)
    {
        foreach ($this->extraData as $key => $value) {
            $extra[$key] = $value;
        }

        return $extra;
    }
private function appendExtraFields(array $extra)
    {
        foreach ($this->extraData as $key => $value) {
            $extra[$key] = $value;
        }

        return $extra;
    }
Adds the extra data into the passed array.

@param array $extra
@return array