✨ Use Pydantic for parameter validation

[svlandeg]

WIP: please don't comment/review yet, this will still change a lot.

Description

Make Pydantic a required dependency and rely on it for parameter validation.

• Pydantic-specific adapter stuff is in the new module adapters.py
• Type-specific stuff is in the new module param_types.py

Extended functionality

• More date time formats are now supported by default, instead of just the three [%Y-%m-%d|%Y-%m-%dT%H:%M:%S|%Y-%m-%d %H:%M:%S]

Breaking changes

• Removed support for click_type and open bounds through min_open and max_open. This greatly simplifies the code base while still providing an alternative by setting parser instead.
• Validation error messages have changed from Click's to Pydantic's phrasing. This mostly requires updating test suites and otherwise shouldn't impact users too badly.
• When not providing a default for DateTime, only one example is shown in the metavar column (%Y-%m-%d instead of [%Y-%m-%d|%Y-%m-%dT%H:%M:%S|%Y-%m-%d %H:%M:%S]) even though all three (and more) will work. It's not just those three anymore, so it felt arbitrary to show 3 out of n. We can decide to reverse the change and keep showing those three formats though.
• TyperPath and TyperChoice were moved into the new module param_types.py

Bug fixes

• def main(age: int = typer.Option(15.3)) will now throw a validation error by Pydantic instead of int(15.3) converting it to 15. I consider this a bug fix instead of a regression, and have added a test test_int_rejects_float_default for it.
• loc: str = typer.Option(..., resolve_path=True) is now parsed as a TyperPath instead of as a STRING on master.

Decision points

• _parse_cli_bool was created to ensure we still parse "" as False and to strip whitespace from something like " True ". This is just to mimic old Click behaviour. If we don't do this preprocessing (cleaner code base), the empty string and the non-stripped strings won't pass Pydantic validation and it would be slightly breaking.

AI Disclaimer

Cursor was used as a micro-managed junior. Every single edit was reviewed & understood by me.

Checklist

• I added tests for the change.
• Coverage stays at 100%.
• The documentation explains the change if needed.

[svlandeg]

This test currently mimics master behaviour 100%.

[github-actions]

📝 Docs preview

Last commit b6165b7 at: https://695fb8cd.typertiangolo.pages.dev