[4.2.x] Fixed #34342, Refs #33735 -- Fixed test client handling of async streaming responses.

Bug in 0bd2c0c9015b53c41394a1c0989afbfd94dc2830.

Co-authored-by: Carlton Gibson <carlton.gibson@noumenal.es>

Backport of 52b054824e899db40ba48f908a9a00dadc56cb89 from main

3 files changed, 27 insertions, 0 deletions

diff --git a/tests/handlers/tests.py b/tests/handlers/tests.py
index 0df481c2fc..0348b8e5d6 100644
--- a/tests/handlers/tests.py
+++ b/tests/handlers/tests.py
@@ -253,6 +253,16 @@ class HandlerRequestTests(SimpleTestCase):
         self.assertEqual(response.status_code, 200)
         self.assertEqual(b"".join(list(response)), b"streaming content")
 
+    def test_async_streaming(self):
+        response = self.client.get("/async_streaming/")
+        self.assertEqual(response.status_code, 200)
+        msg = (
+            "StreamingHttpResponse must consume asynchronous iterators in order to "
+            "serve them synchronously. Use a synchronous iterator instead."
+        )
+        with self.assertWarnsMessage(Warning, msg):
+            self.assertEqual(b"".join(list(response)), b"streaming content")
+
 
 class ScriptNameTests(SimpleTestCase):
     def test_get_script_name(self):
@@ -329,3 +339,10 @@ class AsyncHandlerRequestTests(SimpleTestCase):
             self.assertEqual(
                 b"".join([chunk async for chunk in response]), b"streaming content"
             )
+
+    async def test_async_streaming(self):
+        response = await self.async_client.get("/async_streaming/")
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(
+            b"".join([chunk async for chunk in response]), b"streaming content"
+        )
diff --git a/tests/handlers/urls.py b/tests/handlers/urls.py
index 73d99c7edf..a0efece602 100644
--- a/tests/handlers/urls.py
+++ b/tests/handlers/urls.py
@@ -8,6 +8,7 @@ urlpatterns = [
     path("no_response_fbv/", views.no_response),
     path("no_response_cbv/", views.NoResponse()),
     path("streaming/", views.streaming),
+    path("async_streaming/", views.async_streaming),
     path("in_transaction/", views.in_transaction),
     path("not_in_transaction/", views.not_in_transaction),
     path("not_in_transaction_using_none/", views.not_in_transaction_using_none),
diff --git a/tests/handlers/views.py b/tests/handlers/views.py
index 351eb65264..95d663323d 100644
--- a/tests/handlers/views.py
+++ b/tests/handlers/views.py
@@ -65,6 +65,15 @@ async def async_regular(request):
     return HttpResponse(b"regular content")
 
 
+async def async_streaming(request):
+    async def async_streaming_generator():
+        yield b"streaming"
+        yield b" "
+        yield b"content"
+
+    return StreamingHttpResponse(async_streaming_generator())
+
+
 class CoroutineClearingView:
     def __call__(self, request):
         """Return an unawaited coroutine (common error for async views)."""