try to use locale.strxfrm

openlp/core/utils/__init__.py

@@ -376,16 +376,21 @@ def format_time(text, local_time):
 def get_locale_key(string):
     """
     Creates a key for case insensitive, locale aware string sorting.
+
+    ``string``
+        The corresponding string.
     """
     string = string.lower()
     # For Python 3 on platforms other than Windows ICU is not necessary. In those cases locale.strxfrm(str) can be used.
+    if os.name == 'nt':
         global ICU_COLLATOR
         if ICU_COLLATOR is None:
-        from languagemanager import LanguageManager
-        locale = LanguageManager.get_language()
-        icu_locale = icu.Locale(locale)
+            from .languagemanager import LanguageManager
+            language = LanguageManager.get_language()
+            icu_locale = icu.Locale(language)
             ICU_COLLATOR = icu.Collator.createInstance(icu_locale)
         return ICU_COLLATOR.getSortKey(string)
+    return locale.strxfrm(string).encode()
 
 
 def get_natural_key(string):

tests/functional/openlp_core_utils/test_utils.py

@@ -105,14 +105,33 @@ class TestUtils(TestCase):
         # THEN: The file name should be cleaned.
         assert result == wanted_name, u'The file name should not contain any special characters.'
 
-    def get_locale_key_test(self):
+    def get_locale_key_windows_test(self):
         """
         Test the get_locale_key(string) function
         """
-        with patch(u'openlp.core.utils.languagemanager.LanguageManager.get_language') as mocked_get_language:
+        with patch(u'openlp.core.utils.languagemanager.LanguageManager.get_language') as mocked_get_language,  \
+                patch(u'openlp.core.utils.os') as mocked_os:
             # GIVEN: The language is German
             # 0x00C3 (A with diaresis) should be sorted as "A". 0x00DF (sharp s) should be sorted as "ss".
             mocked_get_language.return_value = u'de'
+            mocked_os.name = u'nt'
+            unsorted_list = [u'Auszug', u'Aushang', u'\u00C4u\u00DFerung']
+            # WHEN: We sort the list and use get_locale_key() to generate the sorting keys
+            # THEN: We get a properly sorted list
+            test_passes = sorted(unsorted_list, key=get_locale_key) == [u'Aushang', u'\u00C4u\u00DFerung', u'Auszug']
+            assert test_passes, u'Strings should be sorted properly'
+
+    def get_locale_key_linux_test(self):
+
+        """
+        Test the get_locale_key(string) function
+        """
+        with patch(u'openlp.core.utils.languagemanager.LanguageManager.get_language') as mocked_get_language,  \
+                patch(u'openlp.core.utils.os.name') as mocked_os:
+            # GIVEN: The language is German
+            # 0x00C3 (A with diaresis) should be sorted as "A". 0x00DF (sharp s) should be sorted as "ss".
+            mocked_get_language.return_value = u'de'
+            mocked_os.name = u'linux'
             unsorted_list = [u'Auszug', u'Aushang', u'\u00C4u\u00DFerung']
             # WHEN: We sort the list and use get_locale_key() to generate the sorting keys
             # THEN: We get a properly sorted list