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Author: serhiy-storchaka

Lib/locale.py

@@ -375,6 +375,8 @@ def _replace_encoding(code, encoding):
 def _append_modifier(code, modifier):
     if modifier == 'euro':
         if '.' not in code:
+            # Linux appears to require keeping the "@euro" modifier in place,
+            # even when using the ".ISO8859-15" encoding.
             return code + '.ISO8859-15@euro'
         _, _, encoding = code.partition('.')
         if encoding == 'UTF-8':
@@ -485,9 +487,9 @@ def _parse_localename(localename):
         # Deal with locale modifiers
         code, modifier = code.split('@', 1)
         if modifier == 'euro' and '.' not in code:
-            # Assume Latin-9 for @euro locales. This is bogus,
-            # since some systems may use other encodings for these
-            # locales.
+            # Assume ISO8859-15 for @euro locales. Do note that some systems
+            # may use other encodings for these locales, so this may not always
+            # be correct.
             return code + '@euro', 'ISO8859-15'
     else:
         modifier = ''

Tools/i18n/makelocalealias.py

@@ -45,6 +45,10 @@ def parse(filename):
         if len(locale) == 1 and locale != 'c':
             continue
         if '@' in locale and '@' not in alias:
+            # Do not simply remove the "@euro" modifier.
+            # Glibc generates separate locales with the "@euro" modifier, and
+            # not always generates a locale without it with the same encoding.
+            # It can also affect collation.
             if locale.endswith('@euro') and not locale.endswith('.utf-8@euro'):
                 alias += '@euro'
         # Normalize encoding, if given
@@ -54,7 +58,7 @@ def parse(filename):
             encoding = encoding.replace('_', '')
             locale = lang + '.' + encoding
         data[locale] = alias
-    # Conflict with GNU libc
+    # Conflict with glibc.
     data.pop('el_gr@euro', None)
     data.pop('uz_uz@cyrillic', None)
     data.pop('uz_uz.utf8@cyrillic', None)