Non-initialized public typed properties on mailables throw an exception

[j3j5]

Laravel Version

10.42.0

PHP Version

8.2.7

Database Driver & Version

No response

Description

When using Mailables, all public properties are made available to the view, that's expected behavior. But if the mailable contains a public (typed) variable that hasn't been initialized, the buildViewData() method throws an exception
Typed property App\Mail\YourClass::$variable must not be accessed before initialization.

I think there should be a check on buildViewData() to make sure typed variables are initialized before being passed to the view.

Steps To Reproduce

php artisan make:mail OrderShipped

<?php

namespace App\Mail;

use App\Models\User;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Mail\Mailable;
use Illuminate\Mail\Mailables\Content;
use Illuminate\Mail\Mailables\Envelope;
use Illuminate\Queue\SerializesModels;

class OrderShipped extends Mailable
{
    public User $user;

    use Queueable, SerializesModels;

    /**
     * Create a new message instance.
     */
    public function __construct()
    {
        //
    }

Then, try to send this mailable, from tinker:

$mail = $mail = new App\Mail\OrderShipped();
Mail::to("mail@example.org")->send($mail);

It will throw an exception

Error Typed property App\Mail\OrderShipped::$user must not be accessed before initialization.