Extend ObjectType

[staabm]

That's not very useful - it'd work only inside function bodies and not across the boundaries when passing object around.

But with this limitation in mind it's possible, you need to extend ObjectType and carry the additional information. phpstan-doctrine does this.

Originally posted by @ondrejmirtes in phpstan/phpstan#6634 (comment)

[staabm]

Instead of using generic types to hold BOTH type information, we should put the type info into a subclass of ObjectType, so we don't suffer from generic type errors as we currently do:

Property MyClass::$stmt with generic class PDOStatement does not
         specify its types: TRowTypeInFetchMode, TRowTypeBoth
         💡 You can turn this off by setting checkGenericClassInNonGenericObjectType: false in your
         phpstan.neon.dist.

---

this should also make phpstan-dba analysis possible across method boundaries.
atm all parts required for the inference need to be accessible from a single method.

I guess cases like

    public function querySelected(PDO $pdo): PDOStatement
    {
        return $pdo->query('SELECT email, adaid, gesperrt, freigabe1u1 FROM ada');
    }

    public function fetch(PDO $pdo):array {
       $stmt = $this->querySelected($pdo);
       return $stmt->fetch();
    }

    public function workWithData(PDO $pdo) {
       $data = $this->fetch($pdo);
       assertType('string', $data['email']);
    }

should work after we use the ObjectType properly

[staabm]

I guess this is related: https://github.com/phpstan/phpstan-doctrine/blob/346484d79c6543dd54ba9d32525e97c6992d86fe/src/Type/Doctrine/QueryBuilder/QueryBuilderType.php