From a54dab3b36bcf0d815b9244f52ae7bc5da08f387 Mon Sep 17 00:00:00 2001
From: "patchback[bot]" <45432694+patchback[bot]@users.noreply.github.com>
Date: Sun, 21 Jan 2024 21:39:11 +0000
Subject: [PATCH] [PR #8049/a379e634 backport][3.9] Set cause for
 ClientPayloadError (#8050)

**This is a backport of PR #8049 as merged into master
(a379e6344432d5c033f78c2733fe69659e3cff50).**
---
 aiohttp/client_proto.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/aiohttp/client_proto.py b/aiohttp/client_proto.py
index 6225b33667c..ca99808080d 100644
--- a/aiohttp/client_proto.py
+++ b/aiohttp/client_proto.py
@@ -81,11 +81,11 @@ def connection_lost(self, exc: Optional[BaseException]) -> None:
         if self._parser is not None:
             try:
                 uncompleted = self._parser.feed_eof()
-            except Exception:
+            except Exception as e:
                 if self._payload is not None:
-                    self._payload.set_exception(
-                        ClientPayloadError("Response payload is not completed")
-                    )
+                    exc = ClientPayloadError("Response payload is not completed")
+                    exc.__cause__ = e
+                    self._payload.set_exception(exc)
 
         if not self.is_eof():
             if isinstance(exc, OSError):