Support Pydantic V2

[koxudaxi]

Pydantic V2 changes some behavior.
This issue should list all related issues and PRs related to V2.

• Add an error when __root__ is set in the model. Add error message for root model in v2 #696
• Strict mode type-checking.
• Validator without a model.
• Required and Nullable behavior like dataclass
• Aliases in Field
• Warning removed methods.
• Respect conversion types table in type-checking.
• Suggest running migration tools for v2
  • Jump to v2 migration documents
  • Run v2 migration tool

[samuelcolvin]

Thanks so much for pinging me @koxudaxi.

In general this sounds great, a few pointers:

• [ALPHA] V2 Alpha Blog Post pydantic/pydantic#5343 contains what migration guide we have, it'll be improved today ahead of the first alpha
• Add auto generate conversion table to doc pydantic/pydantic#5324 contains code for the conversion table that you should ultimately be able to use when marking arguments as valid or invalid, please comment their if you have any feedback
• auto-migration tool for Pydantic V2 pydantic/pydantic#5013 for details on an auto-migration tool
• most of the warnings on removed methods should already work since pycharm spots DeprecationWarning and puts a line through the function.

[koxudaxi]

@samuelcolvin
I'm checking the links.
Btw, Thank you for sponsoring me 🙇

[samuelcolvin]

No problem, thank you for everything you've done.

[davidgilbertson]

I notice you have Alias in this list, does that mean you're aware already of this issue where it only picks up on the alias, not the original name?

If not, you want me to create a separate issue?