From da6424e96ada72c15c91bddb0a411acf7119e10a Mon Sep 17 00:00:00 2001
From: Manjusaka <lizheao940510@gmail.com>
Date: Wed, 23 Jan 2019 15:08:38 +0800
Subject: [PATCH] bpo-35726: Prevented QueueHandler formatting from affecting
 other handlers (GH-11537)

QueueHandler.prepare() now makes a copy of the record before modifying and enqueueing it, to avoid affecting other handlers in the chain.
---
 Lib/logging/handlers.py                                        | 3 +++
 .../next/Library/2019-01-13-01-33-00.bpo-35726.dasdas.rst      | 1 +
 2 files changed, 4 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2019-01-13-01-33-00.bpo-35726.dasdas.rst

diff --git a/Lib/logging/handlers.py b/Lib/logging/handlers.py
index e213e438c31..3727bf0677c 100644
--- a/Lib/logging/handlers.py
+++ b/Lib/logging/handlers.py
@@ -27,6 +27,7 @@ import logging, socket, os, pickle, struct, time, re
 from stat import ST_DEV, ST_INO, ST_MTIME
 import queue
 import threading
+import copy
 
 #
 # Some constants...
@@ -1377,6 +1378,8 @@ class QueueHandler(logging.Handler):
         # exc_info and exc_text attributes, as they are no longer
         # needed and, if not None, will typically not be pickleable.
         msg = self.format(record)
+        # bpo-35726: make copy of record to avoid affecting other handlers in the chain.
+        record = copy.copy(record)
         record.message = msg
         record.msg = msg
         record.args = None
diff --git a/Misc/NEWS.d/next/Library/2019-01-13-01-33-00.bpo-35726.dasdas.rst b/Misc/NEWS.d/next/Library/2019-01-13-01-33-00.bpo-35726.dasdas.rst
new file mode 100644
index 00000000000..f47cdc128e8
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-01-13-01-33-00.bpo-35726.dasdas.rst
@@ -0,0 +1 @@
+QueueHandler.prepare() now makes a copy of the record before modifying and enqueueing it, to avoid affecting other handlers in the chain.