Fix TypeError with evaluate_forward_ref on some 3.10 and 3.9 versions (#558)

Daraan · web-flow · commit 5ce0e69b2099 · 2025-04-01T08:38:35.000-07:00
python/cpython#30926
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -3,6 +3,8 @@
 Bugfixes and changed features:
 - Fix regression in 4.13.0 on Python 3.10.2 causing a `TypeError` when using `Concatenate`.
   Patch by [Daraan](https://github.com/Daraan).
+- Fix `TypeError` when using `evaluate_forward_ref` on Python 3.10.1-2 and 3.9.8-10.
+  Patch by [Daraan](https://github.com/Daraan).
 
 # Release 4.13.0 (March 25, 2025)
 
diff --git a/src/typing_extensions.py b/src/typing_extensions.py
@@ -4371,7 +4371,11 @@ def _lax_type_check(
         A lax Python 3.11+ like version of typing._type_check
         """
         if hasattr(typing, "_type_convert"):
-            if _FORWARD_REF_HAS_CLASS:
+            if (
+                sys.version_info >= (3, 10, 3)
+                or (3, 9, 10) < sys.version_info[:3] < (3, 10)
+            ):
+                # allow_special_forms introduced later cpython/#30926 (bpo-46539)
                 type_ = typing._type_convert(
                     value,
                     module=module,
