laravel-ide-helper 遇到There are no commands defined问题怎么解决

laravel门面类的代码提示方案：
https://github.com/barryvdh/laravel-ide-helper
按照步骤安装

1、composer require barryvdh/laravel-ide-helper

2、添加下面这行到config\app.php的providers数组项中

Barryvdh\LaravelIdeHelper\IdeHelperServiceProvider::class,

3、php artisan ide-helper:generate

这时候报错

[Symfony\Component\Console\Exception\CommandNotFoundException]

There are no commands defined in the "ide-helper" namespace.

php artisan clear-compiled

php artisan optimize

都没用

最后是运行

php artisan config:clear

再执行php artisan ide-helper:generate就成功了