Why does `requireValue` default to false?

[Ramon Dantas]

Detailed description

Mostly just a question, but is there a specific reason why the requireValue option on the Field attribute defaults to false? It seems a bit weird IMO, because this allows code like the following to work:

use Crell\Serde\SerdeCommon;

class User {
    public function __construct(
        public readonly string $name,
        public readonly string $address
    ) {}
}

$serde = new SerdeCommon();

$json = '{}';
$user = $serde->deserialize($json, from: 'json', to: User::class);

Context

Defaulting to requiring the value to be present on deserialization if the property has no default value would be a less surprising behavior; and also lower the amount of attributes needed to achieve this behavior

Possible implementation

Changing the default value, or making it configurable at the Serde level somehow

Your environment

PHP 8.1

[Larry Garfield]

The main reason is that it was implemented rather late, and changing the default would have been a BC break. It also broke about a third of the existing tests, and my attempts to fix it were taking too long so I backed that out.

There is a class-level setting to require values for all properties. If you set #[ClassSettings(requireValues: true)], then all properties will default to required unless they override it back to false themselves.

See the bulleted list under here: https://github.com/Crell/Serde#configuration

[Ramon Dantas]

I see, using the class-level attribute does help a lot, but it would be interesting to have some kind of serializer-level configuration for this IMO, maybe something like new SerdeCommon(requireValues: true)

[Larry Garfield]

Possibly, but I am very wary of adding what is effectively a deformatter or importer specific property to the main API. The only way to do that in an extensible fashion is with an array of values that can get read somewhere, but... no, that is not an API. 😄 Avoiding that was a key design goal for Serde vs Symfony.