<!-- Thank you for your contribution! -->
<!-- Unless your change is trivial, please create an issue to discuss the change before creating a PR -->

## Change Summary

I noticed similar or identical logic in several places and extracted a couple of methods to reduce duplication.

The two commits are fairly independent and it may be easier to view their diffs separately to understand the changes. The first is probably a bit more compelling.

Note that the original code replaced by `clean_schema` wasn't always exactly the same, but the differences didn't really strike me as intentional, and either way it seemed good to draw attention to those differences and consider discussing them or adding comments to clarify.

## Related issue number

There's no issue because this isn't fixing/adding anything notable, it's just refactoring. I thought it made more sense to discuss the changes here rather than in a separate issue.

## Checklist

* [x] The pull request title is a good summary of the changes - it will be used in the changelog
* [x] Unit tests for the changes exist
* [x] Tests pass on CI
* [x] Documentation reflects the changes where applicable
* [x] My PR is ready to review, **please add a comment including the phrase "please review" to assign reviewers**


Selected Reviewer: @adriangb
Refactoring schema-related code. <!-- Thank you for your contribution! -->
<!-- Unless your change is trivial, please create an issue to discuss the change before creating a PR -->

## Change Summary

I noticed similar or identical logic in several places and extracted a couple of methods to reduce duplication.

The two commits are fairly independent and it may be easier to view their diffs separately to understand the changes. The first is probably a bit more compelling.

Note that the original code replaced by `clean_schema` wasn't always exactly the same, but the differences didn't really strike me as intentional, and either way it seemed good to draw attention to those differences and consider discussing them or adding comments to clarify.

## Related issue number

There's no issue because this isn't fixing/adding anything notable, it's just refactoring. I thought it made more sense to discuss the changes here rather than in a separate issue.

## Checklist

* [x] The pull request title is a good summary of the changes - it will be used in the changelog
* [x] Unit tests for the changes exist
* [x] Tests pass on CI
* [x] Documentation reflects the changes where applicable
* [x] My PR is ready to review, **please add a comment including the phrase "please review" to assign reviewers**


Selected Reviewer: @adriangb
from __future__ import annotations as _annotations

import inspect
from dataclasses import dataclass
from functools import partial
from typing import Any, Awaitable, Callable

import pydantic_core

from ..config import ConfigDict
from ..plugin._schema_validator import create_schema_validator
from . import _discriminated_union, _generate_schema, _typing_extra
from ._config import ConfigWrapper
from ._core_utils import simplify_schema_references, validate_core_schema


@dataclass
class CallMarker:
    function: Callable[..., Any]
    validate_return: bool


class ValidateCallWrapper:
    """This is a wrapper around a function that validates the arguments passed to it, and optionally the return value.

    It's partially inspired by `wraps` which in turn uses `partial`, but extended to be a descriptor so
    these functions can be applied to instance methods, class methods, static methods, as well as normal functions.
    """

    __slots__ = (
        'raw_function',
        '_config',
        '_validate_return',
        '__pydantic_core_schema__',
        '__pydantic_validator__',
        '__signature__',
        '__name__',
        '__qualname__',
        '__annotations__',
        '__dict__',  # required for __module__
    )

    def __init__(self, function: Callable[..., Any], config: ConfigDict | None, validate_return: bool):
        self.raw_function = function
        self._config = config
        self._validate_return = validate_return
        self.__signature__ = inspect.signature(function)
        if isinstance(function, partial):
            func = function.func
            self.__name__ = f'partial({func.__name__})'
            self.__qualname__ = f'partial({func.__qualname__})'
            self.__annotations__ = func.__annotations__
            self.__module__ = func.__module__
            self.__doc__ = func.__doc__
        else:
            self.__name__ = function.__name__
            self.__qualname__ = function.__qualname__
            self.__annotations__ = function.__annotations__
            self.__module__ = function.__module__
            self.__doc__ = function.__doc__

        namespace = _typing_extra.add_module_globals(function, None)
        config_wrapper = ConfigWrapper(config)
        gen_schema = _generate_schema.GenerateSchema(config_wrapper, namespace)
        schema = gen_schema.collect_definitions(gen_schema.generate_schema(function))
        schema = simplify_schema_references(schema)
        self.__pydantic_core_schema__ = schema = schema
        core_config = config_wrapper.core_config(self)
        schema = _discriminated_union.apply_discriminators(schema)
        self.__pydantic_validator__ = create_schema_validator(schema, core_config, config_wrapper.plugin_settings)

        if self._validate_return:
            return_type = (
                self.__signature__.return_annotation
                if self.__signature__.return_annotation is not self.__signature__.empty
                else Any
            )
            gen_schema = _generate_schema.GenerateSchema(config_wrapper, namespace)
            schema = gen_schema.collect_definitions(gen_schema.generate_schema(return_type))
            schema = _discriminated_union.apply_discriminators(simplify_schema_references(schema))
            self.__return_pydantic_core_schema__ = schema
            core_config = config_wrapper.core_config(self)
            schema = validate_core_schema(schema)
            validator = pydantic_core.SchemaValidator(schema, core_config)
            if inspect.iscoroutinefunction(self.raw_function):

                async def return_val_wrapper(aw: Awaitable[Any]) -> None:
                    return validator.validate_python(await aw)

                self.__return_pydantic_validator__ = return_val_wrapper
            else:
                self.__return_pydantic_validator__ = validator.validate_python
        else:
            self.__return_pydantic_core_schema__ = None
            self.__return_pydantic_validator__ = None

        self._name: str | None = None  # set by __get__, used to set the instance attribute when decorating methods

    def __call__(self, *args: Any, **kwargs: Any) -> Any:
        res = self.__pydantic_validator__.validate_python(pydantic_core.ArgsKwargs(args, kwargs))
        if self.__return_pydantic_validator__:
            return self.__return_pydantic_validator__(res)
        return res

    def __get__(self, obj: Any, objtype: type[Any] | None = None) -> ValidateCallWrapper:
        """Bind the raw function and return another ValidateCallWrapper wrapping that."""
        if obj is None:
            try:
                # Handle the case where a method is accessed as a class attribute
                return objtype.__getattribute__(objtype, self._name)  # type: ignore
            except AttributeError:
                # This will happen the first time the attribute is accessed
                pass

        bound_function = self.raw_function.__get__(obj, objtype)
        result = self.__class__(bound_function, self._config, self._validate_return)
        if self._name is not None:
            if obj is not None:
                object.__setattr__(obj, self._name, result)
            else:
                object.__setattr__(objtype, self._name, result)
        return result

    def __set_name__(self, owner: Any, name: str) -> None:
        self._name = name

    def __repr__(self) -> str:
        return f'ValidateCallWrapper({self.raw_function})'

from __future__ import annotations as _annotations

import inspect
from dataclasses import dataclass
from functools import partial
from typing import Any, Awaitable, Callable

import pydantic_core

from ..config import ConfigDict
from ..plugin._schema_validator import create_schema_validator
from . import _generate_schema, _typing_extra
from ._config import ConfigWrapper


@dataclass
class CallMarker:
    function: Callable[..., Any]
    validate_return: bool


class ValidateCallWrapper:
    """This is a wrapper around a function that validates the arguments passed to it, and optionally the return value.

    It's partially inspired by `wraps` which in turn uses `partial`, but extended to be a descriptor so
    these functions can be applied to instance methods, class methods, static methods, as well as normal functions.
    """

    __slots__ = (
        'raw_function',
        '_config',
        '_validate_return',
        '__pydantic_core_schema__',
        '__pydantic_validator__',
        '__signature__',
        '__name__',
        '__qualname__',
        '__annotations__',
        '__dict__',  # required for __module__
    )

    def __init__(self, function: Callable[..., Any], config: ConfigDict | None, validate_return: bool):
        self.raw_function = function
        self._config = config
        self._validate_return = validate_return
        self.__signature__ = inspect.signature(function)
        if isinstance(function, partial):
            func = function.func
            self.__name__ = f'partial({func.__name__})'
            self.__qualname__ = f'partial({func.__qualname__})'
            self.__annotations__ = func.__annotations__
            self.__module__ = func.__module__
            self.__doc__ = func.__doc__
        else:
            self.__name__ = function.__name__
            self.__qualname__ = function.__qualname__
            self.__annotations__ = function.__annotations__
            self.__module__ = function.__module__
            self.__doc__ = function.__doc__

        namespace = _typing_extra.add_module_globals(function, None)
        config_wrapper = ConfigWrapper(config)
        gen_schema = _generate_schema.GenerateSchema(config_wrapper, namespace)
        schema = gen_schema.clean_schema(gen_schema.generate_schema(function))
        self.__pydantic_core_schema__ = schema
        core_config = config_wrapper.core_config(self)
        self.__pydantic_validator__ = create_schema_validator(schema, core_config, config_wrapper.plugin_settings)

        if self._validate_return:
            return_type = (
                self.__signature__.return_annotation
                if self.__signature__.return_annotation is not self.__signature__.empty
                else Any
            )
            gen_schema = _generate_schema.GenerateSchema(config_wrapper, namespace)
            schema = gen_schema.clean_schema(gen_schema.generate_schema(return_type))
            self.__return_pydantic_core_schema__ = schema
            validator = create_schema_validator(schema, core_config, config_wrapper.plugin_settings)
            if inspect.iscoroutinefunction(self.raw_function):

                async def return_val_wrapper(aw: Awaitable[Any]) -> None:
                    return validator.validate_python(await aw)

                self.__return_pydantic_validator__ = return_val_wrapper
            else:
                self.__return_pydantic_validator__ = validator.validate_python
        else:
            self.__return_pydantic_core_schema__ = None
            self.__return_pydantic_validator__ = None

        self._name: str | None = None  # set by __get__, used to set the instance attribute when decorating methods

    def __call__(self, *args: Any, **kwargs: Any) -> Any:
        res = self.__pydantic_validator__.validate_python(pydantic_core.ArgsKwargs(args, kwargs))
        if self.__return_pydantic_validator__:
            return self.__return_pydantic_validator__(res)
        return res

    def __get__(self, obj: Any, objtype: type[Any] | None = None) -> ValidateCallWrapper:
        """Bind the raw function and return another ValidateCallWrapper wrapping that."""
        if obj is None:
            try:
                # Handle the case where a method is accessed as a class attribute
                return objtype.__getattribute__(objtype, self._name)  # type: ignore
            except AttributeError:
                # This will happen the first time the attribute is accessed
                pass

        bound_function = self.raw_function.__get__(obj, objtype)
        result = self.__class__(bound_function, self._config, self._validate_return)
        if self._name is not None:
            if obj is not None:
                object.__setattr__(obj, self._name, result)
            else:
                object.__setattr__(objtype, self._name, result)
        return result

    def __set_name__(self, owner: Any, name: str) -> None:
        self._name = name

    def __repr__(self) -> str:
        return f'ValidateCallWrapper({self.raw_function})'
