Nullable required properties during denormalization

[qdequippe]

Jane version(s) affected: 7.6.0

Description

When a Component Schema contains required fields (see example on how to reproduce) and if these fields are nullable, isset conditions blocks sub object denormalization.

How to reproduce

Giving this component

{
    "BlocAdresse-1": {
        "type": "object",
        "properties": {
            ...
            "indiceRepetition": {
                "pattern": "^([A-Z])$",
                "type": "string",
                "example": "T",
                "description": "GU_ADR011",
                "nullable": true
            },
            ...
            "complementLocalisation": {
                "type": "string",
                "example": "Compl\u00e9ment de localisation",
                "description": "GU_ADR016",
                "nullable": true
            },
            ...
        },
        "required": [
            "indiceRepetition",
            "complementLocalisation"
        ]
    }
}

it generates this code sample on parent model

if (\array_key_exists('adresse', $data) && null !== $data['adresse']) {
    $value_1 = $data['adresse'];
    if (\is_array($data['adresse']) && isset($data['adresse']['indiceRepetition'], $data['adresse']['complementLocalisation'])) {
        $value_1 = $this->denormalizer->denormalize($data['adresse'], BlocAdresse1::class, 'json', $context);
    }
    $object->setAdresse($value_1);
    unset($data['adresse']);
}

Excepts that isset check also null values so denormalization will be never call.

Possible Solution

Replace https://github.com/janephp/janephp/blob/next/src/Component/JsonSchema/Guesser/Guess/ObjectType.php#L71-L76 by

$arrayKeyExistsCondition = new Expr\FuncCall(
    new Name('\array_key_exists'),
    [
        new Arg(new Scalar\String_($key)),
        new Arg($input),
    ]
);

However if $input is not an array this solution is not working.

Additional context