Nullable properties are not initialized on deserialization

[simPod]

Q	A
Bug report?	yes
Feature request?	no
BC Break report?	no
RFC?	no

Steps required to reproduce the problem

1. Serialize this

<?php

declare(strict_types=1);

final class A
{
    public string $a;

    public ?string $b;

    public function __construct(string $a, ?string $b)
    {
        $this->a = $a;
        $this->b = $b;
    }
}

serialize(new A("1",null));

2. The json is {"a": "1"}
3. Deserialize it
4. Access $a->b

Expected Result

No error, $a->b gives null

Actual Result

Typed property A::$b must not be accessed before initialization

[goetas]

Hi. I think that you should use the $context->serializeNulls() feature in that case. Did you try it?

[simPod]

Ah right, forgot about that. Works!

BTW shouldn't it be default on PHP 7.4+?

[goetas]

I was thinking to solve it with #1081 but never had time to continue the work on it.

[simPod]

Let's continue there