Laravel 密码Password_Confirmation 验证

我一直在使用它来编辑用户帐户信息:

I've been using this in order to edit the User Account Info:

$this->validate($request, [
    'password' => 'min:6',
    'password_confirmation' => 'required_with:password|same:password|min:6'
]);

这在 Laravel 5.2 应用程序中运行良好，但在 5.4 应用程序中不起作用.

This worked fine in a Laravel 5.2 Application but does not work in a 5.4 Application.

这里出了什么问题，或者只有在 password 或 password_confirmation 字段为设置好了吗?

What's wrong here, or what is the correct way in order to only make the password required if either the password or password_confirmation field is set?