[commands] Add CategoryChannelConverter

discord/ext/commands/converter.py

@@ -35,7 +35,8 @@ from .view import StringView
 __all__ = [ 'Converter', 'MemberConverter', 'UserConverter',
             'TextChannelConverter', 'InviteConverter', 'RoleConverter',
             'GameConverter', 'ColourConverter', 'VoiceChannelConverter',
-            'EmojiConverter', 'IDConverter', 'clean_content' ]
+            'EmojiConverter','CategoryChannelConverter', 'IDConverter',
+            'clean_content' ]
 
 def _get_from_guilds(bot, getter, argument):
     result = None
@@ -242,6 +243,46 @@ class VoiceChannelConverter(IDConverter):
 
         return result
 
+class CategoryChannelConverter(IDConverter):
+    """Converts to a :class:`CategoryChannel`.
+
+    All lookups are via the local guild. If in a DM context, then the lookup
+    is done by the global cache.
+
+    The lookup strategy is as follows (in order):
+
+    1. Lookup by ID.
+    2. Lookup by mention.
+    3. Lookup by name
+    """
+    @asyncio.coroutine
+    def convert(self, ctx, argument):
+        bot = ctx.bot
+
+        match = self._get_id_match(argument) or re.match(r'<#([0-9]+)>$', argument)
+        result = None
+        guild = ctx.guild
+
+        if match is None:
+            # not a mention
+            if guild:
+                result = discord.utils.get(guild.categories, name=argument)
+            else:
+                def check(c):
+                    return isinstance(c, discord.CategoryChannel) and c.name == argument
+                result = discord.utils.find(check, bot.get_all_channels())
+        else:
+            channel_id = int(match.group(1))
+            if guild:
+                result = guild.get_channel(channel_id)
+            else:
+                result = _get_from_guilds(bot, 'get_channel', channel_id)
+
+        if not isinstance(result, discord.CategoryChannel):
+            raise BadArgument('Channel "{}" not found.'.format(argument))
+
+        return result
+
 class ColourConverter(Converter):
     """Converts to a :class:`Colour`.