From 473788d36f9d65186a8127e1bf24e2b61b5dc265 Mon Sep 17 00:00:00 2001
From: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Date: Fri, 17 Dec 2021 09:25:41 -0800
Subject: [PATCH] Handle curses.tigetstr() returning None

Found with python/typeshed#6620
---
 tornado/log.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tornado/log.py b/tornado/log.py
index 810a0373b..869989613 100644
--- a/tornado/log.py
+++ b/tornado/log.py
@@ -151,7 +151,11 @@ class LogFormatter(logging.Formatter):
                     self._colors[levelno] = unicode_type(
                         curses.tparm(fg_color, code), "ascii"
                     )
-                self._normal = unicode_type(curses.tigetstr("sgr0"), "ascii")
+                normal = curses.tigetstr("sgr0")
+                if normal is not None:
+                    self._normal = unicode_type(normal, "ascii")
+                else:
+                    self._normal = ""
             else:
                 # If curses is not present (currently we'll only get here for
                 # colorama on windows), assume hard-coded ANSI color codes.
-- 
2.47.2