From 92c930ab9e2aff10c9c1d69bec1481977d0ad6a6 Mon Sep 17 00:00:00 2001
From: Kadir Can Ozden <101993364+bysiber@users.noreply.github.com>
Date: Fri, 20 Feb 2026 14:19:51 +0300
Subject: [PATCH] Restore _write and _flush in WriteLogger.__setstate__
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After unpickling a WriteLogger, calling any log method (msg, info,
debug, etc.) raises AttributeError because __setstate__ only restores
_file and _lock but not _write and _flush.

BytesLogger.__setstate__ already handles this correctly, and so does
WriteLogger.__deepcopy__ — this was just an oversight in __setstate__.
---
 src/structlog/_output.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/structlog/_output.py b/src/structlog/_output.py
index b1612de6..a35df747 100644
--- a/src/structlog/_output.py
+++ b/src/structlog/_output.py
@@ -186,6 +186,8 @@ def __setstate__(self, state: Any) -> None:
         else:
             self._file = stderr
 
+        self._write = self._file.write
+        self._flush = self._file.flush
         self._lock = _get_lock_for_file(self._file)
 
     def __deepcopy__(self, memodict: dict[str, object]) -> WriteLogger: