From 86bb6ad30c9411a3dc4320b356959a3dc0189eca Mon Sep 17 00:00:00 2001
From: "patchback[bot]" <45432694+patchback[bot]@users.noreply.github.com>
Date: Mon, 2 Dec 2024 01:22:11 +0000
Subject: [PATCH] [PR #10088/29c3ca93 backport][3.11] Avoid calling len on the
 same data in the stream reader twice (#10090)

Co-authored-by: J. Nick Koston <nick@koston.org>
---
 aiohttp/streams.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/aiohttp/streams.py b/aiohttp/streams.py
index b97846171b1..029d577b88c 100644
--- a/aiohttp/streams.py
+++ b/aiohttp/streams.py
@@ -517,8 +517,9 @@ def _read_nowait_chunk(self, n: int) -> bytes:
         else:
             data = self._buffer.popleft()
 
-        self._size -= len(data)
-        self._cursor += len(data)
+        data_len = len(data)
+        self._size -= data_len
+        self._cursor += data_len
 
         chunk_splits = self._http_chunk_splits
         # Prevent memory leak: drop useless chunk splits