Encoding for subprocess.run

Author: Zac-HD

src/_pytest/pytester.py

@@ -6,6 +6,7 @@
 import contextlib
 import gc
 import importlib
+import locale
 import os
 import platform
 import re
@@ -129,6 +130,7 @@ def get_open_files(self) -> List[Tuple[str, str]]:
             stderr=subprocess.DEVNULL,
             check=True,
             text=True,
+            encoding=locale.getpreferredencoding(False),
         ).stdout
 
         def isopen(line: str) -> bool:

testing/test_parseopt.py

@@ -1,4 +1,5 @@
 import argparse
+import locale
 import os
 import shlex
 import subprocess
@@ -296,6 +297,7 @@ def test_argcomplete(pytester: Pytester, monkeypatch: MonkeyPatch) -> None:
             stderr=subprocess.DEVNULL,
             check=True,
             text=True,
+            encoding=locale.getpreferredencoding(False),
         ).stdout
     except (OSError, subprocess.CalledProcessError):
         pytest.skip("bash is not available")