I would suggest limiting the property lookup to the class the getter was declared in ($reflMethod->getDeclaringClass()) and maybe its parents.

Otherwise the results could change by introducing new properties in child classes, which could cause confusion:

class Base
{
    private bool $test = false;

    public function isTest(): bool
    {
        return $this->test;
    }

    public function setTest(bool $test): void
    {
        $this->test = $test;
    }
}

class Child extends Base {
    private bool $isTest = true;
}

$serializer = new Serializer([new ObjectNormalizer()], [new JsonEncoder()]);
echo $serializer->serialize(new Base(), 'json') . PHP_EOL;  // {"test":false}
echo $serializer->serialize(new Child(), 'json') . PHP_EOL; // {"isTest":false}

This is, of course, just a theoretical example, but I can't think of a case in which this behavior could be useful and starting at the most likely correct class would reduce the number of checks/iterations necessary considerably for classes with many inherited properties.

Another thing: I think for consistency's sake the check in line 115 should behave the same way.

I would suggest limiting the property lookup to the class the getter was declared in ($reflMethod->getDeclaringClass()) and maybe its parents.

Otherwise the results could change by introducing new properties in child classes, which could cause confusion:

class Base
{
    private bool $test = false;

    public function isTest(): bool
    {
        return $this->test;
    }

    public function setTest(bool $test): void
    {
        $this->test = $test;
    }
}

class Child extends Base {
    private bool $isTest = true;
}

$serializer = new Serializer([new ObjectNormalizer()], [new JsonEncoder()]);
echo $serializer->serialize(new Base(), 'json') . PHP_EOL;  // {"test":false}
echo $serializer->serialize(new Child(), 'json') . PHP_EOL; // {"isTest":false}

This is, of course, just a theoretical example, but I can't think of a case in which this behavior could be useful and starting at the most likely correct class would reduce the number of checks/iterations necessary considerably for classes with many inherited properties.

Another thing: I think for consistency's sake the check in line 115 should behave the same way.

@frozenbrain, thank you for the feedback, I've made the changes.

Thank you @Link1515.