feat: pass on factory config

[adhtruong]

Pull Request Checklist

• New code has 100% test coverage
• (If applicable) The prose documentation has been updated to reflect the changes introduced by this PR
• (If applicable) The reference documentation has been updated to reflect the changes introduced by this PR
• Pre-Commit Checks were ran and passed
• Tests were ran and passed

Description

Close Issue(s)

• Fixes Bug: factories inside a nested pydantic model with custom types do not inherit the provider map #318
• Fixes Bug: nested collections always have a length of 1 #424
• FIxes Bug: factories created as part of nested models do not inherit class attributes #426

[guacs]

This is really nice! I had considered this approach a while back, but I faced an issue with how to pass the provider map. In the current test case, there wouldn't be any issues since both the parent and child are both dataclasses. The issue becomes when the parent and child are of different base classes. For example, consider a parent class being a pydantic model and a child class being a msgspec Struct. In this case, the child factory (i.e. the factory for the msgspec struct) would get the provider map of the parent pydantic model. However, the default MsgspecFactory overrides the default get_provider_map to inject types specific to msgspec.

The simplest option would be to tell users to not mix these models. It's fine if they mix pydantic with the Python builtins like dataclass, or typeddict since we don't have any special cases to handle there and, so, we don't override the get_provider_map. Maybe we could raise a warning if users are mixing it like that. I think, from a practical standpoint, this is a fine solution since it would probably be rare for them to be mixing something like pydantic and msgspec.

EDIT: Completely disregard what I said. I just realized you're using __extra_provider_map__ to handle this case. With your approach, the issue I mentioned above is not an issue anymore.

[guacs]

This is really great @adhtruong! Thanks a bunch for this :)

Could you add the details regarding this in the docs? This way, if users add custom fields that they want to pass to the child factories, they'll know to override the config keys field.

[adhtruong]

Thanks @guacs for the review! Updated now :)

[github-actions]

Documentation preview will be available shortly at https://litestar-org.github.io/polyfactory-docs-preview/483