Get or fetch member when trying to reply

This fixes an issue where the member may not be in the cache

Author: ChrisLovering

bot.py

@@ -640,6 +640,16 @@ async def get_or_fetch_user(self, id: int) -> discord.User:
         """
         return self.get_user(id) or await self.fetch_user(id)
 
+    @staticmethod
+    async def get_or_fetch_member(guild: discord.Guild, member_id: int) -> typing.Optional[discord.Member]:
+        """
+        Attempt to get a member from cache; on failure fetch from the API.
+
+        Returns:
+            The :obj:`discord.Member` or :obj:`None` to indicate the member could not be found.
+        """
+        return guild.get_member(member_id) or await guild.fetch_member(member_id)
+
     async def retrieve_emoji(self) -> typing.Tuple[str, str]:
         sent_emoji = self.config["sent_emoji"]
         blocked_emoji = self.config["blocked_emoji"]

core/thread.py

@@ -823,7 +823,13 @@ async def reply(
         """Returns List[user_dm_msg] and thread_channel_msg"""
         if not message.content and not message.attachments and not message.stickers:
             raise MissingRequiredArgument(DummyParam("msg"))
-        if not any(g.get_member(self.id) for g in self.bot.guilds):
+        for guild in self.bot.guilds:
+            try:
+                if await self.bot.get_or_fetch_member(guild, self.id):
+                    break
+            except discord.NotFound:
+                pass
+        else:
             return await message.channel.send(
                 embed=discord.Embed(
                     color=self.bot.error_color,