private function listCommands(array &$list, $path, $namespace)
    {
        $classes = [];
        list_classes($classes, $path, $namespace);
        foreach ($classes as $class) {
            /** @var CommandContract $command */
            $command = new $class;
            $name = $command->name();
            $description = trim($command->description() ?: '');
            $list[$name] = compact('class', 'name', 'description');
        }
    }