validate_call type params fix (#9760)

Author: sydney-runkle

pydantic/_internal/_typing_extra.py

@@ -307,6 +307,7 @@ def get_function_type_hints(
 
     globalns = add_module_globals(function)
     type_hints = {}
+    type_params: tuple[Any] = getattr(function, '__type_params__', ())  # type: ignore
     for name, value in annotations.items():
         if include_keys is not None and name not in include_keys:
             continue
@@ -315,7 +316,7 @@ def get_function_type_hints(
         elif isinstance(value, str):
             value = _make_forward_ref(value)
 
-        type_hints[name] = eval_type_backport(value, globalns, types_namespace)
+        type_hints[name] = eval_type_backport(value, globalns, types_namespace, type_params)
 
     return type_hints
 

pydantic/_internal/_validate_call.py

@@ -23,7 +23,13 @@ class ValidateCallWrapper:
         '__dict__',  # required for __module__
     )
 
-    def __init__(self, function: Callable[..., Any], config: ConfigDict | None, validate_return: bool):
+    def __init__(
+        self,
+        function: Callable[..., Any],
+        config: ConfigDict | None,
+        validate_return: bool,
+        namespace: dict[str, Any] | None,
+    ):
         if isinstance(function, partial):
             func = function.func
             schema_type = func
@@ -36,7 +42,16 @@ def __init__(self, function: Callable[..., Any], config: ConfigDict | None, vali
             self.__qualname__ = function.__qualname__
             self.__module__ = function.__module__
 
-        namespace = _typing_extra.add_module_globals(function, None)
+        global_ns = _typing_extra.add_module_globals(function, None)
+        # TODO: this is a bit of a hack, we should probably have a better way to handle this
+        # specifically, we shouldn't be pumping the namespace full of type_params
+        # when we take namespace and type_params arguments in eval_type_backport
+        type_params = getattr(schema_type, '__type_params__', ())
+        namespace = {
+            **{param.__name__: param for param in type_params},
+            **(global_ns or {}),
+            **(namespace or {}),
+        }
         config_wrapper = ConfigWrapper(config)
         gen_schema = _generate_schema.GenerateSchema(config_wrapper, namespace)
         schema = gen_schema.clean_schema(gen_schema.generate_schema(function))

pydantic/validate_call_decorator.py

@@ -5,7 +5,7 @@
 import functools
 from typing import TYPE_CHECKING, Any, Callable, TypeVar, overload
 
-from ._internal import _validate_call
+from ._internal import _typing_extra, _validate_call
 
 __all__ = ('validate_call',)
 
@@ -46,12 +46,14 @@ def validate_call(
     Returns:
         The decorated function.
     """
+    local_ns = _typing_extra.parent_frame_namespace()
 
     def validate(function: AnyCallableT) -> AnyCallableT:
         if isinstance(function, (classmethod, staticmethod)):
             name = type(function).__name__
             raise TypeError(f'The `@{name}` decorator should be applied after `@validate_call` (put `@{name}` on top)')
-        validate_call_wrapper = _validate_call.ValidateCallWrapper(function, config, validate_return)
+
+        validate_call_wrapper = _validate_call.ValidateCallWrapper(function, config, validate_return, local_ns)
 
         @functools.wraps(function)
         def wrapper_function(*args, **kwargs):

tests/test_validate_call.py

@@ -1,6 +1,7 @@
 import asyncio
 import inspect
 import re
+import sys
 from datetime import datetime, timezone
 from functools import partial
 from typing import Any, List, Tuple
@@ -803,3 +804,59 @@ def foo(bar: 'list[int | str]') -> 'list[int | str]':
             'input': {'not a str or int'},
         },
     ]
+
+
+@pytest.mark.skipif(sys.version_info < (3, 12), reason='requires Python 3.12+ for PEP 695 syntax with generics')
+def test_validate_call_with_pep_695_syntax() -> None:
+    """Note: validate_call still doesn't work properly with generics, see https://github.com/pydantic/pydantic/issues/7796.
+
+    This test is just to ensure that the syntax is accepted and doesn't raise a NameError."""
+    globs = {}
+    exec(
+        """
+from typing import Iterable
+from pydantic import validate_call
+
+@validate_call
+def find_max_no_validate_return[T](args: Iterable[T]) -> T:
+    return sorted(args, reverse=True)[0]
+
+@validate_call(validate_return=True)
+def find_max_validate_return[T](args: Iterable[T]) -> T:
+    return sorted(args, reverse=True)[0]
+        """,
+        globs,
+    )
+    functions = [globs['find_max_no_validate_return'], globs['find_max_validate_return']]
+    for find_max in functions:
+        assert len(find_max.__type_params__) == 1
+        assert find_max([1, 2, 10, 5]) == 10
+
+        with pytest.raises(ValidationError):
+            find_max(1)
+
+
+class M0(BaseModel):
+    z: int
+
+
+M = M0
+
+
+def test_uses_local_ns():
+    class M1(BaseModel):
+        y: int
+
+    M = M1  # noqa: F841
+
+    def foo():
+        class M2(BaseModel):
+            z: int
+
+        M = M2
+
+        @validate_call
+        def bar(m: M) -> M:
+            return m
+
+        assert bar({'z': 1}) == M2(z=1)