src/Request.php
public static function restoreEnv(&$env, $key) {
        $key = strtoupper($key);

        if (isset($env[$key.'_RAW'])) {
            $env[$key] = $env[$key.'_RAW'];
            unset($env[$key.'_RAW']);
            return $env[$key];
        } elseif (isset($env[$key])) {
            return $env[$key];
        }
        return null;
    }
public static function restoreEnv(&$env, $key) {
        $key = strtoupper($key);

        if (isset($env[$key.'_RAW'])) {
            $env[$key] = $env[$key.'_RAW'];
            unset($env[$key.'_RAW']);
            return $env[$key];
        } elseif (isset($env[$key])) {
            return $env[$key];
        }
        return null;
    }
Restore an environment variable that was replaced with {@link Request::replaceEnv()}.

@param array &$env The environment array.
@param string $key The environment key.
@return mixed Returns the current environment value.