hg-legacywindowsfsencoding.patch

diff -r ffdfb1066ac6 contrib/win32/hg.bat
--- a/contrib/win32/hg.bat	Thu Mar 02 15:34:45 2023 +0100
+++ b/contrib/win32/hg.bat	Wed Jun 28 18:53:44 2023 +0900
@@ -5,6 +5,7 @@
 set HG=%~f0
 
 set PYTHONLEGACYWINDOWSSTDIO=1
+set PYTHONLEGACYWINDOWSFSENCODING=1
 
 rem Use a full path to Python (relative to this script) if it exists,
 rem as the standard Python install does not put python.exe on the PATH...
diff -r ffdfb1066ac6 mercurial/exewrapper.c
--- a/mercurial/exewrapper.c	Thu Mar 02 15:34:45 2023 +0100
+++ b/mercurial/exewrapper.c	Wed Jun 28 18:53:44 2023 +0900
@@ -49,6 +49,7 @@
 
 #if PY_MAJOR_VERSION >= 3
 	_wputenv(L"PYTHONLEGACYWINDOWSSTDIO=1");
+	_wputenv(L"PYTHONLEGACYWINDOWSFSENCODING=1");
 #endif
 
 	if (GetModuleFileName(NULL, pyscript, _countof(pyscript)) == 0) {
diff -r ffdfb1066ac6 mercurial/pycompat.py
--- a/mercurial/pycompat.py	Thu Mar 02 15:34:45 2023 +0100
+++ b/mercurial/pycompat.py	Wed Jun 28 18:53:44 2023 +0900
@@ -110,13 +110,6 @@
     return _rapply(f, xs)
 
 
-if os.name == r'nt':
-    # MBCS (or ANSI) filesystem encoding must be used as before.
-    # Otherwise non-ASCII filenames in existing repositories would be
-    # corrupted.
-    # This must be set once prior to any fsencode/fsdecode calls.
-    sys._enablelegacywindowsfsencoding()  # pytype: disable=module-attr
-
 fsencode = os.fsencode
 fsdecode = os.fsdecode
 oscurdir: bytes = os.curdir.encode('ascii')
@@ -171,17 +164,11 @@
     #
     # On Windows, the wchar_t **argv is passed into the interpreter as-is.
     # Like POSIX, we need to emulate what Py_EncodeLocale() would do. But
-    # there's an additional wrinkle. What we really want to access is the
-    # ANSI codepage representation of the arguments, as this is what
-    # `int main()` would receive if Python 3 didn't define `int wmain()`
-    # (this is how Python 2 worked). To get that, we encode with the mbcs
-    # encoding, which will pass CP_ACP to the underlying Windows API to
-    # produce bytes.
-    sysargv: List[bytes] = []
-    if os.name == r'nt':
-        sysargv = [a.encode("mbcs", "ignore") for a in sys.argv]
-    else:
-        sysargv = [fsencode(a) for a in sys.argv]
+    # When PYTHONLEGACYWINDOWSFSENCODING is set, fsencde/fsdecode uses
+    # ANSI codepage. This is backward compatible.
+    # Otherwise, Python uses UTF-8 on Windows too. This is good for hg-git
+    # and new repositories.
+    sysargv: List[bytes] = [fsencode(a) for a in sys.argv]
 
 bytechr = struct.Struct('>B').pack
 byterepr = b'%r'.__mod__
diff -r ffdfb1066ac6 tests/run-tests.py
--- a/tests/run-tests.py	Thu Mar 02 15:34:45 2023 +0100
+++ b/tests/run-tests.py	Wed Jun 28 18:53:44 2023 +0900
@@ -1462,6 +1462,7 @@
         # dummysmtpd.py, and dumbhttp.py.
         if WINDOWS:
             env['PYTHONLEGACYWINDOWSSTDIO'] = '1'
+            env['PYTHONLEGACYWINDOWSFSENCODING'] = '1'
 
         # Modified HOME in test environment can confuse Rust tools. So set
         # CARGO_HOME and RUSTUP_HOME automatically if a Rust toolchain is