Add django.db.models.fields.related.ForeignObject missing methods and attributes

[JaeHyuckSa]

I have made things!

Some of the Django 5.0 updates were missing from the related classes, so I added them referring to the allowlist_todo.

If you need any additional work, please let me know and I'll work on it right away. Thank you :)

django.db.models.ForeignObject

• django.db.models.ForeignObject.__copy__
• django.db.models.ForeignObject.contribute_to_related_class
• django.db.models.ForeignObject.forward_related_accessor_class
• django.db.models.ForeignObject.get_class_lookups
• django.db.models.ForeignObject.get_extra_descriptor_filter
• django.db.models.ForeignObject.get_foreign_related_value
• django.db.models.ForeignObject.get_instance_value_for_fields
• django.db.models.ForeignObject.get_joining_columns
• django.db.models.ForeignObject.get_local_related_value
• django.db.models.ForeignObject.get_path_info
• django.db.models.ForeignObject.get_reverse_joining_columns
• django.db.models.ForeignObject.get_reverse_path_info
• django.db.models.ForeignObject.related_accessor_class
• django.db.models.ForeignObject.requires_unique_target

Related issues

• 5.0: Update django.db.models.field.related #2151

[sobolevn]

Looks like this class has lots of unsolved problems. Let's solve them!

1. Please, use ClassVar where needed: https://github.com/django/django/blob/a09082a9bec18f8e3ee8c10d473013ec67ffe93b/django/db/models/fields/related.py#L522-L530

[JaeHyuckSa]

Thank you. As you suggested, I have handled all the relevant parts as class variables.

[sobolevn]

2. Let's add other missing attributes to ForeignObject

[JaeHyuckSa]

I have two questions:

1. I tried to define the get_extra_restriction method, but I encountered an error due to the parameter mismatch with the subclass. I attempted to use type: ignore on the method in the subclass, but it was not allowed. What steps can I take to resolve this issue?

error: not checking stubs due to mypy build errors:
django-stubs/contrib/contenttypes/fields.pyi:90: error: Signature of "get_extra_restriction" incompatible with supertype "ForeignObject"  [override]
django-stubs/contrib/contenttypes/fields.pyi:90: note:      Superclass:
django-stubs/contrib/contenttypes/fields.pyi:90: note:          def get_extra_restriction(self, alias: str, related_alias: str) -> None
django-stubs/contrib/contenttypes/fields.pyi:90: note:      Subclass:
django-stubs/contrib/contenttypes/fields.pyi:90: note:          def get_extra_restriction(self, where_class: Type[WhereNode], alias: Optional[str], remote_alias: str) -> WhereNode
django-stubs/contrib/contenttypes/fields.pyi:92: error: Unused "type: ignore" comment  [unused-ignore]

2. Should I also add the cached_property method?

[intgr]

I think this should actually be Self

The Empty class is just an artifact of a weird hack that Django uses, but it modifies the __class__ attribute so that it's no longer actually the Empty class

    def __copy__(self):
        # We need to avoid hitting __reduce__, so define this
        # slightly weird copy construct.
        obj = Empty()
        obj.__class__ = self.__class__
        obj.__dict__ = self.__dict__.copy()
        return obj

[JaeHyuckSa]

Based on your explanation, that seems correct. Thank you for pointing that out!