✨ Allow `None` as return type for bodiless responses (#9425)

Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

fastapi/dependencies/utils.py

@@ -254,6 +254,8 @@ def get_typed_annotation(annotation: Any, globalns: Dict[str, Any]) -> Any:
     if isinstance(annotation, str):
         annotation = ForwardRef(annotation)
         annotation = evaluate_forwardref(annotation, globalns, globalns)
+        if annotation is type(None):
+            return None
     return annotation
 
 

tests/test_return_none_stringified_annotations.py

@@ -0,0 +1,17 @@
+import http
+
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+
+def test_no_content():
+    app = FastAPI()
+
+    @app.get("/no-content", status_code=http.HTTPStatus.NO_CONTENT)
+    def return_no_content() -> "None":
+        return
+
+    client = TestClient(app)
+    response = client.get("/no-content")
+    assert response.status_code == http.HTTPStatus.NO_CONTENT, response.text
+    assert not response.content