Remove duplicate mentions from reminder arguments

This also accounts for the author passing themselves to mention, and
therefore avoids the user from being told they're not allowed to mention
themselves even though they could.

1 files changed, 10 insertions, 2 deletions

diff --git a/bot/cogs/reminders.py b/bot/cogs/reminders.py
index 1410bfea6..60fa70d74 100644
--- a/bot/cogs/reminders.py
+++ b/bot/cogs/reminders.py
@@ -104,7 +104,7 @@ class Reminders(Cog):
         await ctx.send(embed=embed)
 
     @staticmethod
-    async def _check_mentions(ctx: Context, mentions: t.List[Mentionable]) -> t.Tuple[bool, str]:
+    async def _check_mentions(ctx: Context, mentions: t.Iterable[Mentionable]) -> t.Tuple[bool, str]:
         """
         Returns whether or not the list of mentions is allowed.
 
@@ -121,7 +121,7 @@ class Reminders(Cog):
             return True, ""
 
     @staticmethod
-    async def validate_mentions(ctx: Context, mentions: t.List[Mentionable]) -> bool:
+    async def validate_mentions(ctx: Context, mentions: t.Iterable[Mentionable]) -> bool:
         """
         Filter mentions to see if the user can mention, and sends a denial if not allowed.
 
@@ -256,6 +256,10 @@ class Reminders(Cog):
                 await send_denial(ctx, "You have too many active reminders!")
                 return
 
+        # Remove duplicate mentions
+        mentions = set(mentions)
+        mentions.discard(ctx.author)
+
         # Filter mentions to see if the user can mention members/roles
         if not await self.validate_mentions(ctx, mentions):
             return
@@ -374,6 +378,10 @@ class Reminders(Cog):
     @edit_reminder_group.command(name="mentions", aliases=("pings",))
     async def edit_reminder_mentions(self, ctx: Context, id_: int, mentions: Greedy[Mentionable]) -> None:
         """Edit one of your reminder's mentions."""
+        # Remove duplicate mentions
+        mentions = set(mentions)
+        mentions.discard(ctx.author)
+
         # Filter mentions to see if the user can mention members/roles
         if not await self.validate_mentions(ctx, mentions):
             return