Add variants for `dataclasses/tutorial002`

docs/en/docs/advanced/dataclasses.md

@@ -32,7 +32,7 @@ But if you have a bunch of dataclasses laying around, this is a nice trick to us
 
 You can also use `dataclasses` in the `response_model` parameter:
 
-{* ../../docs_src/dataclasses/tutorial002.py hl[1,7:13,19] *}
+{* ../../docs_src/dataclasses/tutorial002_py310.py hl[1,6:12,18] *}
 
 The dataclass will be automatically converted to a Pydantic dataclass.
 

docs_src/dataclasses/tutorial002_py310.py

@@ -0,0 +1,25 @@
+from dataclasses import dataclass, field
+
+from fastapi import FastAPI
+
+
+@dataclass
+class Item:
+    name: str
+    price: float
+    tags: list[str] = field(default_factory=list)
+    description: str | None = None
+    tax: float | None = None
+
+
+app = FastAPI()
+
+
+@app.get("/items/next", response_model=Item)
+async def read_next_item():
+    return {
+        "name": "Island In The Moon",
+        "price": 12.99,
+        "description": "A place to be playin' and havin' fun",
+        "tags": ["breater"],
+    }

docs_src/dataclasses/tutorial002_py39.py

@@ -0,0 +1,26 @@
+from dataclasses import dataclass, field
+from typing import Union
+
+from fastapi import FastAPI
+
+
+@dataclass
+class Item:
+    name: str
+    price: float
+    tags: list[str] = field(default_factory=list)
+    description: Union[str, None] = None
+    tax: Union[float, None] = None
+
+
+app = FastAPI()
+
+
+@app.get("/items/next", response_model=Item)
+async def read_next_item():
+    return {
+        "name": "Island In The Moon",
+        "price": 12.99,
+        "description": "A place to be playin' and havin' fun",
+        "tags": ["breater"],
+    }

tests/test_tutorial/test_dataclasses/test_tutorial002.py

@@ -1,12 +1,29 @@
+import importlib
+
+import pytest
 from dirty_equals import IsDict, IsOneOf
 from fastapi.testclient import TestClient
 
-from docs_src.dataclasses.tutorial002 import app
+from tests.utils import needs_py39, needs_py310
+
+
+@pytest.fixture(
+    name="client",
+    params=[
+        pytest.param("tutorial002"),
+        pytest.param("tutorial002_py39", marks=needs_py39),
+        pytest.param("tutorial002_py310", marks=needs_py310),
+    ],
+)
+def get_client(request: pytest.FixtureRequest):
+    mod = importlib.import_module(f"docs_src.dataclasses.{request.param}")
 
-client = TestClient(app)
+    client = TestClient(mod.app)
+    client.headers.clear()
+    return client
 
 
-def test_get_item():
+def test_get_item(client: TestClient):
     response = client.get("/items/next")
     assert response.status_code == 200
     assert response.json() == {
@@ -18,7 +35,7 @@ def test_get_item():
     }
 
 
-def test_openapi_schema():
+def test_openapi_schema(client: TestClient):
     response = client.get("/openapi.json")
     assert response.status_code == 200
     assert response.json() == {