bpo-43510: Implement PEP 597 opt-in EncodingWarning. (GH-19481)
See [PEP 597](https://www.python.org/dev/peps/pep-0597/).
* Add `-X warn_default_encoding` and `PYTHONWARNDEFAULTENCODING`.
* Add EncodingWarning
* Add io.text_encoding()
* open(), TextIOWrapper() emits EncodingWarning when encoding is omitted and warn_default_encoding is enabled.
* _pyio.TextIOWrapper() uses UTF-8 as fallback default encoding used when failed to import locale module. (used during building Python)
* bz2, configparser, gzip, lzma, pathlib, tempfile modules use io.text_encoding().
* What's new entry
diff --git a/Lib/site.py b/Lib/site.py
index 5f1b31e..939893e 100644
--- a/Lib/site.py
+++ b/Lib/site.py
@@ -170,7 +170,9 @@ def addpackage(sitedir, name, known_paths):
fullname = os.path.join(sitedir, name)
_trace(f"Processing .pth file: {fullname!r}")
try:
- f = io.TextIOWrapper(io.open_code(fullname))
+ # locale encoding is not ideal especially on Windows. But we have used
+ # it for a long time. setuptools uses the locale encoding too.
+ f = io.TextIOWrapper(io.open_code(fullname), encoding="locale")
except OSError:
return
with f: