diff --git a/tests/test_pydantic_v1_v2_01.py b/tests/test_pydantic_v1_v2_01.py
index 5c8d4daa4..0b9033423 100644
--- a/tests/test_pydantic_v1_v2_01.py
+++ b/tests/test_pydantic_v1_v2_01.py
@@ -33,6 +33,19 @@ def handle_old_models_filter(data: SubItem) -> Any:
     return extended_data
 
 
+@app.post("/item")
+def handle_item(data: Item) -> Item:
+    return data
+
+
+@app.post("/item-filter", response_model=Item)
+def handle_item_filter(data: Item) -> Any:
+    extended_data = data.dict()
+    extended_data.update({"secret_data": "classified", "internal_id": 12345})
+    extended_data["sub"].update({"internal_id": 67890})
+    return extended_data
+
+
 client = TestClient(app)
 
 
@@ -73,6 +86,130 @@ def test_old_simple_model_filter():
     assert response.json() == {"name": "Foo"}
 
 
+def test_item_model():
+    response = client.post(
+        "/item",
+        json={
+            "title": "Test Item",
+            "size": 100,
+            "description": "This is a test item",
+            "sub": {"name": "SubItem1"},
+            "multi": [{"name": "Multi1"}, {"name": "Multi2"}]
+        },
+    )
+    assert response.status_code == 200, response.text
+    assert response.json() == {
+        "title": "Test Item",
+        "size": 100,
+        "description": "This is a test item",
+        "sub": {"name": "SubItem1"},
+        "multi": [{"name": "Multi1"}, {"name": "Multi2"}]
+    }
+
+
+def test_item_model_minimal():
+    response = client.post(
+        "/item",
+        json={
+            "title": "Minimal Item",
+            "size": 50,
+            "sub": {"name": "SubMin"}
+        },
+    )
+    assert response.status_code == 200, response.text
+    assert response.json() == {
+        "title": "Minimal Item",
+        "size": 50,
+        "description": None,
+        "sub": {"name": "SubMin"},
+        "multi": []
+    }
+
+
+def test_item_model_validation_errors():
+    response = client.post(
+        "/item",
+        json={
+            "title": "Missing fields"
+        },
+    )
+    assert response.status_code == 422, response.text
+    error_detail = response.json()["detail"]
+    assert len(error_detail) == 2
+    assert {"loc": ["body", "size"], "msg": "field required", "type": "value_error.missing"} in error_detail
+    assert {"loc": ["body", "sub"], "msg": "field required", "type": "value_error.missing"} in error_detail
+
+
+def test_item_model_nested_validation_error():
+    response = client.post(
+        "/item",
+        json={
+            "title": "Test Item",
+            "size": 100,
+            "sub": {"wrong_field": "test"}
+        },
+    )
+    assert response.status_code == 422, response.text
+    assert response.json() == snapshot(
+        {
+            "detail": [
+                {
+                    "loc": ["body", "sub", "name"],
+                    "msg": "field required",
+                    "type": "value_error.missing",
+                }
+            ]
+        }
+    )
+
+
+def test_item_model_invalid_type():
+    response = client.post(
+        "/item",
+        json={
+            "title": "Test Item",
+            "size": "not_a_number",
+            "sub": {"name": "SubItem"}
+        },
+    )
+    assert response.status_code == 422, response.text
+    assert response.json() == snapshot(
+        {
+            "detail": [
+                {
+                    "loc": ["body", "size"],
+                    "msg": "value is not a valid integer",
+                    "type": "type_error.integer",
+                }
+            ]
+        }
+    )
+
+
+def test_item_filter():
+    response = client.post(
+        "/item-filter",
+        json={
+            "title": "Filtered Item",
+            "size": 200,
+            "description": "Test filtering",
+            "sub": {"name": "SubFiltered"},
+            "multi": []
+        },
+    )
+    assert response.status_code == 200, response.text
+    result = response.json()
+    assert result == {
+        "title": "Filtered Item",
+        "size": 200,
+        "description": "Test filtering",
+        "sub": {"name": "SubFiltered"},
+        "multi": []
+    }
+    assert "secret_data" not in result
+    assert "internal_id" not in result
+
+
 def test_openapi_schema():
     response = client.get("/openapi.json")
     assert response.status_code == 200, response.text
@@ -162,8 +299,75 @@ def test_openapi_schema():
                             },
                         },
                     }
+                }, "/item": {
+    "post": {
+        "summary": "Handle Item",
+        "operationId": "handle_item_item_post",
+        "requestBody": {
+            "content": {
+                "application/json": {
+                    "schema": {
+                        "allOf": [{"$ref": "#/components/schemas/Item"}],
+                        "title": "Data",
+                    }
+                }
+            },
+            "required": True,
+        },
+        "responses": {
+            "200": {
+                "description": "Successful Response",
+                "content": {
+                    "application/json": {
+                        "schema": {"$ref": "#/components/schemas/Item"}
+                    }
+                },
+            },
+            "422": {
+                "description": "Validation Error",
+                "content": {
+                    "application/json": {
+                        "schema": {"$ref": "#/components/schemas/HTTPValidationError"}
+                    }
+                },
+            },
+        },
+    }
+}, "/item-filter": {
+    "post": {
+        "summary": "Handle Item Filter",
+        "operationId": "handle_item_filter_item_filter_post",
+        "requestBody": {
+            "content": {
+                "application/json": {
+                    "schema": {
+                        "allOf": [{"$ref": "#/components/schemas/Item"}],
+                        "title": "Data",
+                    }
+                }
+            },
+            "required": True,
+        },
+        "responses": {
+            "200": {
+                "description": "Successful Response",
+                "content": {
+                    "application/json": {
+                        "schema": {"$ref": "#/components/schemas/Item"}
+                    }
                 },
             },
+            "422": {
+                "description": "Validation Error",
+                "content": {
+                    "application/json": {
+                        "schema": {"$ref": "#/components/schemas/HTTPValidationError"}
+                    }
+                },
+            },
+        },
+    }
+}},
             "components": {
                 "schemas": {
                     "HTTPValidationError": {
@@ -178,8 +382,23 @@ def test_openapi_schema():
                         },
                         "type": "object",
                         "title": "HTTPValidationError",
-                    },
-                    "SubItem": {
+                    }, "Item": {
+    "properties": {
+        "title": {"type": "string", "title": "Title"},
+        "size": {"type": "integer", "title": "Size"},
+        "description": {"type": "string", "title": "Description"},
+        "sub": {"$ref": "#/components/schemas/SubItem"},
+        "multi": {
+            "items": {"$ref": "#/components/schemas/SubItem"},
+            "type": "array",
+            "title": "Multi",
+            "default": [],
+        },
+    },
+    "type": "object",
+    "required": ["title", "size", "sub"],
+    "title": "Item",
+}, "SubItem": {
                         "properties": {"name": {"type": "string", "title": "Name"}},
                         "type": "object",
                         "required": ["name"],
@@ -205,6 +424,3 @@ def test_openapi_schema():
             },
         }
     )
-
-
-# test_openapi_schema()