Extract type param scope instead of copying globals dict

Author: dr-carlos

Lib/annotationlib.py

@@ -161,14 +161,17 @@ def evaluate(
             # as a way of emulating annotation scopes when calling `eval()`
             type_params = getattr(owner, "__type_params__", None)
 
-        # Type parameters exist in their own scope, which is logically
-        # between the locals and the globals. We simulate this by adding
-        # them to the globals. Similar reasoning applies to nonlocals stored in cells.
-        if type_params is not None or isinstance(self.__cell__, dict):
+        # Nonlocals logically sit between the locals and the globals. We simulate this
+        # by overriding the globals.
+        if isinstance(self.__cell__, dict):
             globals = dict(globals)
+
+        # Type parameters exist in their own scope, which is logically
+        # between the locals and the globals.
+        type_param_scope = {}
         if type_params is not None:
             for param in type_params:
-                globals[param.__name__] = param
+                type_param_scope[param.__name__] = param
         if isinstance(self.__cell__, dict):
             for cell_name, cell_value in self.__cell__.items():
                 try:
@@ -182,6 +185,8 @@ def evaluate(
         if arg.isidentifier() and not keyword.iskeyword(arg):
             if arg in locals:
                 return locals[arg]
+            elif arg in type_param_scope:
+                return type_param_scope[arg]
             elif arg in globals:
                 return globals[arg]
             elif hasattr(builtins, arg):
@@ -193,15 +198,15 @@ def evaluate(
         else:
             code = self.__forward_code__
             try:
-                return eval(code, globals=globals, locals=locals)
+                return eval(code, globals=globals, locals={**type_param_scope, **locals})
             except Exception:
                 if not is_forwardref_format:
                     raise
 
             # All variables, in scoping order, should be checked before
             # triggering __missing__ to create a _Stringifier.
             new_locals = _StringifierDict(
-                {**builtins.__dict__, **globals, **locals},
+                {**builtins.__dict__, **globals, **type_param_scope, **locals},
                 globals=globals,
                 owner=owner,
                 is_class=self.__forward_is_class__,