fix: compatibility with pydantic 2.13 (#142)

azmeuk · web-flow · commit cc4b3ef13a8c · 2026-04-13T14:35:38.000+02:00
diff --git a/doc/changelog.rst b/doc/changelog.rst
@@ -1,6 +1,13 @@
 Changelog
 =========
 
+[0.6.11] - 2026-04-13
+---------------------
+
+Added
+^^^^^
+- Compatibility with Pydantic 2.13.
+
 [0.6.11] - 2026-04-10
 ---------------------
 
diff --git a/scim2_models/resources/resource.py b/scim2_models/resources/resource.py
@@ -1,3 +1,4 @@
+import copyreg
 from datetime import datetime
 from typing import TYPE_CHECKING
 from typing import Annotated
@@ -409,14 +410,10 @@ def _dedicated_attributes(
     """Return attributes that are not members the parent 'excluded_models'."""
 
     def compare_field_infos(fi1: Any, fi2: Any) -> bool:
-        return (
-            fi1
-            and fi2
-            and fi1.__slotnames__ == fi2.__slotnames__
-            and all(
-                getattr(fi1, attr) == getattr(fi2, attr) for attr in fi1.__slotnames__
-            )
-        )
+        if not fi1 or not fi2:
+            return False
+        slot_names = copyreg._slotnames(type(fi1))  # type: ignore[attr-defined]
+        return all(getattr(fi1, attr) == getattr(fi2, attr) for attr in slot_names)
 
     parent_field_infos = {
         field_name: field_info
diff --git a/tests/test_dynamic_schemas.py b/tests/test_dynamic_schemas.py
@@ -1,6 +1,8 @@
+import copyreg
 import operator
 
 import pytest
+from pydantic.fields import FieldInfo
 
 from scim2_models import URN
 from scim2_models.context import Context
@@ -155,6 +157,25 @@ class Bar(Foo):
     }
 
 
+def test_to_schema_without_slotnames_cache():
+    """Regression test for ``FieldInfo.__slotnames__`` usage.
+
+    ``FieldInfo.__slotnames__`` is a cache populated lazily by ``copy.copy`` /
+    ``copyreg._slotnames``. Computing a schema must not rely on that cache
+    being already warm, otherwise ``to_schema`` raises ``AttributeError`` on a
+    fresh process.
+    """
+    copyreg._slotnames(FieldInfo)
+    del FieldInfo.__slotnames__
+
+    class Foo(Resource):
+        __schema__ = URN("urn:ietf:params:scim:schemas:core:2.0:Foo")
+
+        foo: str | None = None
+
+    Foo.to_schema()
+
+
 def test_make_python_model_validates_name():
     """Test that make_python_model raises an exception when obj.name is not defined."""
     # Test with Schema object without name
diff --git a/uv.lock b/uv.lock
