diff mercurial/util.py @ 45011:1bab6b61b62b stable

curses: do not initialize LC_ALL to user settings (issue6358)

701341f57ceb moved the setlocale() call to right before curses was used. This
didn’t fully solve the problem it was supposed to solve (locale-dependent
functions, like date formatting/parsing and str methods on Python 2), but only
postponed it.

Initializing LC_CTYPE seems to be sufficient for curses to work correctly.
Therefore LC_CTYPE is set while curses is used and reset afterwards. Some
locale-dependent str methods might behave differently on Python 2 while curses
is used, but that shouldn’d be a problem.

--- a/mercurial/util.py	Thu Jun 25 03:46:07 2020 +0200
+++ b/mercurial/util.py	Sun Jun 28 18:02:45 2020 +0200
@@ -22,6 +22,7 @@
 import gc
 import hashlib
 import itertools
+import locale
 import mmap
 import os
 import platform as pyplatform
@@ -3626,3 +3627,32 @@
         if not (byte & 0x80):
             return result
         shift += 7
+
+
+# Passing the '' locale means that the locale should be set according to the
+# user settings (environment variables).
+# Python sometimes avoids setting the global locale settings. When interfacing
+# with C code (e.g. the curses module or the Subversion bindings), the global
+# locale settings must be initialized correctly. Python 2 does not initialize
+# the global locale settings on interpreter startup. Python 3 sometimes
+# initializes LC_CTYPE, but not consistently at least on Windows. Therefore we
+# explicitly initialize it to get consistent behavior if it's not already
+# initialized. Since CPython commit 177d921c8c03d30daa32994362023f777624b10d,
+# LC_CTYPE is always initialized. If we require Python 3.8+, we should re-check
+# if we can remove this code.
[e-mail]
+def with_lc_ctype():
+    oldloc = locale.setlocale(locale.LC_CTYPE, None)
+    if oldloc == 'C':
+        try:
+            try:
+                locale.setlocale(locale.LC_CTYPE, '')
+            except locale.Error:
+                # The likely case is that the locale from the environment
+                # variables is unknown.
+                pass
+            yield
+        finally:
+            locale.setlocale(locale.LC_CTYPE, oldloc)
+    else:
+        yield