Added alphabetical_sort() function

Author: kmvanbrunt

cmd2/cmd2.py

@@ -1092,7 +1092,7 @@ def complete_users():
             self.allow_closing_quote = False
 
         # Sort the matches before any trailing slashes are added
-        matches.sort(key=str.lower)
+        matches = utils.alphabetical_sort(matches)
         self.matches_sorted = True
 
         # Build display_matches and add a slash to directories
@@ -1532,8 +1532,8 @@ def complete(self, text: str, state: int) -> Optional[str]:
 
             # Sort matches alphabetically if they haven't already been sorted
             if not self.matches_sorted:
-                self.completion_matches.sort(key=str.lower)
-                self.display_matches.sort(key=str.lower)
+                self.completion_matches = utils.alphabetical_sort(self.completion_matches)
+                self.display_matches = utils.alphabetical_sort(self.display_matches)
                 self.matches_sorted = True
 
         try:
@@ -2325,12 +2325,10 @@ def _help_menu(self, verbose: bool=False) -> None:
         """Show a list of commands which help can be displayed for.
         """
         # Get a sorted list of help topics
-        help_topics = self.get_help_topics()
-        help_topics.sort(key=str.lower)
+        help_topics = utils.alphabetical_sort(self.get_help_topics())
 
         # Get a sorted list of visible command names
-        visible_commands = self.get_visible_commands()
-        visible_commands.sort(key=str.lower)
+        visible_commands = utils.alphabetical_sort(self.get_visible_commands())
 
         cmds_doc = []
         cmds_undoc = []

cmd2/utils.py

@@ -157,3 +157,12 @@ def remove_duplicates(list_to_prune: List) -> List:
         temp_dict[item] = None
 
     return list(temp_dict.keys())
+
+
+def alphabetical_sort(list_to_sort: List[str]) -> List[str]:
+    """
+    Sorts a list of strings alphabetically
+    :param list_to_sort: the list being sorted
+    :return: the sorted list
+    """
+    return sorted(list_to_sort, key=str.casefold)

tests/test_completion.py

@@ -410,7 +410,7 @@ def test_delimiter_completion(cmd2_app):
 
     # Remove duplicates from display_matches and sort it. This is typically done in complete().
     display_list = utils.remove_duplicates(cmd2_app.display_matches)
-    display_list.sort(key=str.lower)
+    display_list = utils.alphabetical_sort(display_list)
 
     assert display_list == ['other user', 'user']