python · AlexWaygood · Jun 25, 2024 · Jun 8, 2024 · Jun 9, 2024 · Jun 9, 2024
@@ -4866,10 +4866,12 @@ def test_pep695_generic_with_future_annotations(self):
         self.assertIs(hints_for_A["z"].__args__[0], A_type_params[2])
 
         hints_for_B = get_type_hints(ann_module695.B)
-        self.assertEqual(hints_for_B.keys(), {"x", "y", "z"})
+        self.assertEqual(hints_for_B, {"x": int, "y": str, "z": bytes})
+
+        hints_for_C = get_type_hints(ann_module695.C)
         self.assertEqual(
-            set(hints_for_B.values()) ^ set(ann_module695.B.__type_params__),
-            set()
+            set(hints_for_C.values()),
+            set(ann_module695.C.__type_params__)
         )
 
         hints_for_generic_function = get_type_hints(ann_module695.generic_function)
@@ -4882,6 +4884,16 @@ def test_pep695_generic_with_future_annotations(self):
         self.assertIs(hints_for_generic_function["z"].__origin__, func_t_params[2])
         self.assertIs(hints_for_generic_function["zz"].__origin__, func_t_params[2])
 
+        hints_for_generic_method = get_type_hints(ann_module695.D.generic_method)
+        params = {
+            param.__name__: param
+            for param in ann_module695.D.generic_method.__type_params__
+        }
+        self.assertEqual(
+            hints_for_generic_method,
+            {"x": params["Foo"], "y": params["Bar"], "return": types.NoneType}
+        )
+
     def test_extended_generic_rules_subclassing(self):
         class T1(Tuple[T, KT]): ...
         class T2(Tuple[T, ...]): ...

@@ -17,6 +17,24 @@ class B[T, *Ts, **P]:
     z: P
 
 
+Eggs = int
+Spam = str
+
+
+class C[Eggs, **Spam]:
+    x: Eggs
+    y: Spam
+
+
 def generic_function[T, *Ts, **P](
     x: T, *y: *Ts, z: P.args, zz: P.kwargs
 ) -> None: ...
+
+
+class D:
+    Foo = int
+    Bar = str
+
+    def generic_method[Foo, **Bar](
+        self, x: Foo, y: Bar
+    ) -> None: ...
@@ -1060,15 +1060,25 @@ def _evaluate(self, globalns, localns, type_params=_sentinel, *, recursive_guard
                 globalns = getattr(
                     sys.modules.get(self.__forward_module__, None), '__dict__', globalns
                 )
-            if type_params:
-                # "Inject" type parameters into the local namespace
-                # (unless they are shadowed by assignments *in* the local namespace),
-                # as a way of emulating annotation scopes when calling `eval()`
-                locals_to_pass = {param.__name__: param for param in type_params} | localns
+
+            # type parameters require some special handling,
+            # as they exist in their own scope
+            # but `eval()` does not have a dedicated parameter for that scope.
+            # For classes, names in type parameter scopes should override
+            # names in the global scope (which here are called `localns`!),
+            # but should in turn be overridden by names in the class scope
+            # (which here are called `globalns`!)
+            type_params = {param.__name__: param for param in type_params}
+            if self.__forward_is_class__:
+                for name, param in type_params.items():
+                    if name not in globalns:
+                        globalns[name] = param
+                        localns.pop(name, None)
             else:
-                locals_to_pass = localns
+                localns = type_params | localns
+
             type_ = _type_check(
-                eval(self.__forward_code__, globalns, locals_to_pass),
+                eval(self.__forward_code__, globalns, localns),
                 "Forward references must evaluate to types.",
                 is_argument=self.__forward_is_argument__,
                 allow_special_forms=self.__forward_is_class__,

diff --git a/Misc/NEWS.d/next/Library/2024-06-08-15-46-35.gh-issue-114053.Ub2XgJ.rst b/Misc/NEWS.d/next/Library/2024-06-08-15-46-35.gh-issue-114053.Ub2XgJ.rst
@@ -0,0 +1,4 @@
+Fix edge-case bug where :func:`typing.get_type_hints` would produce
+incorrect results if type parameters in a class scope were overridden by
+assignments in a class scope and ``from __future__ import annotations``
+semantics were enabled. Patch by Alex Waygood.