factory boy override django auto_now_add

__init__.py

from typing import Generic, TypeVar, get_args

import factory
from factory.base import FactoryMetaClass


def _override_auto_now_add_fields(obj, kwargs):
    """
    That's a built-in "feature" of Django: when a field has auto_now_add=True, Django will override any provided value
    with django.utils.timezone.now() ; this happens "after" factory_boy's code runs.

    To overcome this we can re-save the object if any of those fields were passed.

    Source: https://github.com/FactoryBoy/factory_boy/issues/102#issuecomment-28010862
    """
    auto_now_add_fields = {f.name for f in obj.__class__._meta.fields if getattr(f, "auto_now_add", False)}
    update_fields = auto_now_add_fields.intersection(kwargs)
    if update_fields:
        for field in update_fields:
            setattr(obj, field, kwargs[field])
        obj.save(update_fields=update_fields)


class BaseFactoryMeta(FactoryMetaClass):
    """
    Source: https://github.com/FactoryBoy/factory_boy/issues/468#issuecomment-1536373442
    Modified for ruff
    """

    def __new__(cls, class_name, bases: list[type], attrs):
        orig_bases = attrs.get("__orig_bases__", [])
        for t in orig_bases:
            if t.__name__ == "BaseFactory" and t.__module__ == __name__:
                type_args = get_args(t)
                if len(type_args) == 1:
                    if "Meta" not in attrs:
                        attrs["Meta"] = type("Meta", (), {})
                    attrs["Meta"].model = type_args[0]
        return super().__new__(cls, class_name, bases, attrs)


T = TypeVar("T", bound=factory.django.DjangoModelFactory)


class BaseFactory(Generic[T], factory.django.DjangoModelFactory, metaclass=BaseFactoryMeta):
    """
    Source: https://github.com/FactoryBoy/factory_boy/issues/468#issuecomment-1536373442
    Modified for DjangoModelFactory and typing clues.
    """

    class Meta:
        abstract = True

    def __new__(cls, *args, **kwargs) -> T:
        return super().__new__(*args, **kwargs)

    @classmethod
    def create(cls, **kwargs) -> T:
        obj = super().create(**kwargs)
        _override_auto_now_add_fields(obj, kwargs)
        return obj

    @classmethod
    def build(cls, **kwargs) -> T:
        return super().build(**kwargs)