Ensure error is raised when reading from closed client response. (#8878) (#8902)

Author: Dreamsorcerer

CHANGES/8878.bugfix.rst

@@ -0,0 +1 @@
+Fixed response reading from closed session to throw an error immediately instead of timing out -- by :user:`Dreamsorcerer`.

aiohttp/streams.py

@@ -296,6 +296,9 @@ def end_http_chunk_receiving(self) -> None:
             set_result(waiter, None)
 
     async def _wait(self, func_name: str) -> None:
+        if not self._protocol.connected:
+            raise RuntimeError("Connection closed.")
+
         # StreamReader uses a future to link the protocol feed_data() method
         # to a read coroutine. Running two read coroutines at the same time
         # would have an unexpected behaviour. It would not possible to know

tests/test_client_functional.py

@@ -29,7 +29,7 @@
     SocketTimeoutError,
     TooManyRedirects,
 )
-from aiohttp.pytest_plugin import AiohttpClient, TestClient
+from aiohttp.pytest_plugin import AiohttpClient, AiohttpServer, TestClient
 from aiohttp.test_utils import unused_port
 
 
@@ -3645,3 +3645,20 @@ async def handler(_: web.Request) -> web.Response:
     session = await aiohttp_client(app, raise_for_status=None)  # type: ignore[arg-type]
 
     await session.get("/")
+
+
+async def test_exception_when_read_outside_of_session(
+    aiohttp_server: AiohttpServer,
+) -> None:
+    async def handler(request: web.Request) -> web.Response:
+        return web.Response(body=b"1" * 1000000)
+
+    app = web.Application()
+    app.router.add_get("/", handler)
+
+    server = await aiohttp_server(app)
+    async with aiohttp.ClientSession() as sess:
+        resp = await sess.get(server.make_url("/"))
+
+    with pytest.raises(RuntimeError, match="Connection closed"):
+        await resp.read()