fix: support pydantic 2.13 by invalidating cached model schema

ormar/models/helpers/relations.py

@@ -192,20 +192,28 @@ def serialize(
         by excluding the children.
         """
         try:
-            with warnings.catch_warnings():
-                warnings.filterwarnings(
-                    "ignore", message="Pydantic serializer warnings"
-                )
-                return handler(children)
-        except ValueError as exc:  # pragma: no cover
-            if not str(exc).startswith("Circular reference"):
-                raise exc
-
-            result = []
-            for child in children:
-                # If there is one circular ref dump all children as pk only
-                result.append({child.ormar_config.pkname: child.pk})
-            return result
+            try:
+                with warnings.catch_warnings():
+                    warnings.filterwarnings(
+                        "ignore", message="Pydantic serializer warnings"
+                    )
+                    return handler(children)
+            except ValueError as exc:  # pragma: no cover
+                if not str(exc).startswith("Circular reference"):
+                    raise exc
+
+                result = []
+                for child in children:
+                    if not hasattr(child, "ormar_config"):
+                        continue
+                    # If there is one circular ref dump all children as pk only
+                    result.append({child.ormar_config.pkname: child.pk})
+                return result
+        except ReferenceError:
+            # Pydantic >= 2.13 may invoke this serializer with weakref
+            # children whose referent is already gone (e.g. when ormar's
+            # late metaclass rebuild changed dispatch ordering).
+            return None
 
     decorator = field_serializer(related_name, mode="wrap", check_fields=False)(
         serialize

ormar/models/metaclass.py

@@ -632,17 +632,26 @@ def serialize(
         Serialize a value if it's not expired weak reference.
         """
         try:
-            with warnings.catch_warnings():
-                warnings.filterwarnings(
-                    "ignore", message="Pydantic serializer warnings"
-                )
-                return handler(value)
+            try:
+                with warnings.catch_warnings():
+                    warnings.filterwarnings(
+                        "ignore", message="Pydantic serializer warnings"
+                    )
+                    return handler(value)
+            except ValueError as exc:
+                if not str(exc).startswith("Circular reference"):
+                    raise exc
+                # Pydantic >= 2.13 dispatches the wrap serializer with
+                # broader value types (e.g. QuerysetProxy for M2M reverse
+                # accessors) where 2.12 unwrapped to Model first. Earlier
+                # pydantic versions never reach this branch with a non-
+                # Model value, so the None return is uncovered on the
+                # 2.11 floor pinned in CI.
+                if value is None or not hasattr(value, "ormar_config"):
+                    return None  # pragma: no cover
+                return {value.ormar_config.pkname: value.pk}
         except ReferenceError:
             return None
-        except ValueError as exc:
-            if not str(exc).startswith("Circular reference"):
-                raise exc
-            return {value.ormar_config.pkname: value.pk} if value else None
 
     return serialize
 
@@ -753,10 +762,24 @@ def __new__(  # type: ignore # noqa: CCR001
                             None,
                         )
                     )
-                    new_model.model_rebuild(force=True)
-
                 new_model.pk = PkDescriptor(name=new_model.ormar_config.pkname)
 
+            if not (
+                new_model.ormar_config.abstract
+                or new_model.ormar_config.proxy
+                or new_model.ormar_config.requires_ref_update
+            ):
+                # Pydantic >= 2.13 changed how TypeAdapter(Annotated[T,
+                # FieldInfo(...)]) resolves nested schemas — it now uses
+                # the cached child snapshot instead of walking the live
+                # model. Reverse-relation fields added by
+                # expand_reverse_relationships above become invisible
+                # from nested dumps unless we invalidate the cached
+                # schema. Mark incomplete so the next access (or the
+                # FastAPI-style TypeAdapter wrapper) recompiles afresh
+                # without the stale snapshot.
+                new_model.__pydantic_complete__ = False  # type: ignore[attr-defined]
+
         return new_model
 
     @property

pyproject.toml

@@ -46,7 +46,9 @@ classifiers = [
 
 [tool.poetry.dependencies]
 python = "^3.10.0"
-pydantic = "^2.11.9"
+# Pinned below 2.14 because ormar relies on pydantic internals; bump the
+# upper bound manually after verifying compatibility with each new release.
+pydantic = ">=2.11.9,<2.14"
 SQLAlchemy = {version = "^2.0.40", extras = ["asyncio"]}
 cryptography = { version = ">=44.0.1,<49.0.0", optional = true }
 # Async database drivers