From 594413e8f05268bc0d448d37022c502af28e1244 Mon Sep 17 00:00:00 2001
From: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Date: Fri, 30 Sep 2022 23:43:27 +0100
Subject: [PATCH] Use an explicit encoding when opening `os.devnul`

Although slightly pointless, this avoids an `EncodingWarning` in Python 3.10
or greater when running under the `-X warn_default_encoding` flag.
---
 src/_pytest/capture.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/_pytest/capture.py b/src/_pytest/capture.py
index bcfd3449f..6131a46df 100644
--- a/src/_pytest/capture.py
+++ b/src/_pytest/capture.py
@@ -381,7 +381,7 @@ class FDCaptureBinary:
         self.targetfd_save = os.dup(targetfd)
 
         if targetfd == 0:
-            self.tmpfile = open(os.devnull)
+            self.tmpfile = open(os.devnull, encoding="utf-8")
             self.syscapture = SysCapture(targetfd)
         else:
             self.tmpfile = EncodedFile(