Unable to add attributes to a subclass of PlayerEntity in __new__?

[satoon101]

I actually noticed this change last night and wondered what it was for:
https://github.com/Source-Python-Dev-Team/Source.Python/blob/master/addons/source-python/packages/source-python/players/weapons/projectiles.py#L18

That line used to be:

Syntax: Select all

class _ProjectileMeta(type):

Having tested, it seems that using 'type' instead causes the same error you are getting, but also crashes the server on plugin_load. I tested changing your example to use BaseEntity.__class__, but that still gave the same error. Changing it to use PlayerEntity.__class__, however, seems to work fine:

Syntax: Select all

from players.entity import PlayerEntity


class MetaTest(PlayerEntity.__class__):

    def __new__(cls, name, bases, attrs):
        attrs['_instances'] = dict()
        return super(MetaTest, cls).__new__(cls, name, bases, attrs)


class Test(PlayerEntity, metaclass=MetaTest):

    def __new__(cls, index):
        if index not in cls._instances:
            cls._instances[index] = super(Test, cls).__new__(cls, index)
        return cls._instances[index]


class Test2(Test):
    ...


class Test3(Test):
    ...


one = Test(1)
two = Test2(1)
three = Test3(1)
print(one)
print(two)
print(three)
print(Test(1))

And that outputs:

Code: Select all

<new.new.Test object at 0x1E5C6900>
<new.new.Test2 object at 0x1E5C6930>
<new.new.Test3 object at 0x1E5C6960>
<new.new.Test object at 0x1E5C6900>

[Mahi]

Interesting. So you're unaware of why this issue is happening? I can't find any classes related to player class that even use metaclasses... Well, I'll just use type(PlayerEntity) for now. Thanks for the help!

[satoon101]

It has to be due to the fact that we are inheriting from BaseEntity. If you change the example to use Entity instead of PlayerEntity, the same error is encountered:

Syntax: Select all

from entities.entity import Entity


class MetaTest(type):

    def __new__(cls, name, bases, attrs):
        attrs['_instances'] = dict()
        return super(MetaTest, cls).__new__(cls, name, bases, attrs)


class Test(Entity, metaclass=MetaTest):

    def __new__(cls, index):
        if index not in cls._instances:
            cls._instances[index] = super(Test, cls).__new__(cls, index)
        return cls._instances[index]


class Test2(Test):
    ...


class Test3(Test):
    ...


one = Test(1)
two = Test2(1)
three = Test3(1)
print(one)
print(two)
print(three)
print(Test(1))

However, changing 'type' to Entity.__class__ works as it should. type(Entity) gives you the same object as Entity.__class__ (same for PlayerEntity), so either way works.

[Mahi]

Alright, good to know. But yeah, I'm fine with using type(PlayerEntity) as long as it works! And I'm aware of type(x) == x.__class__, but I've always found type() better looking and less-hacky