[commands] Add role cooldown bucket

2 files changed, 11 insertions, 1 deletions

diff --git a/discord/ext/commands/cooldowns.py b/discord/ext/commands/cooldowns.py
index 5cd305f6..57577a07 100644
--- a/discord/ext/commands/cooldowns.py
+++ b/discord/ext/commands/cooldowns.py
@@ -27,6 +27,8 @@ DEALINGS IN THE SOFTWARE.
 from discord.enums import Enum
 import time
 
+from ...abc import PrivateChannel
+
 __all__ = (
     'BucketType',
     'Cooldown',
@@ -40,6 +42,7 @@ class BucketType(Enum):
     channel  = 3
     member   = 4
     category = 5
+    role     = 6
 
 class Cooldown:
     __slots__ = ('rate', 'per', 'type', '_window', '_tokens', '_last')
@@ -127,6 +130,12 @@ class CooldownMapping:
             return ((msg.guild and msg.guild.id), msg.author.id)
         elif bucket_type is BucketType.category:
             return (msg.channel.category or msg.channel).id
+        elif bucket_type is BucketType.role:
+            # we return the channel id of a private-channel as there are only roles in guilds
+            # and that yields the same result as for a guild with only the @everyone role
+            # NOTE: PrivateChannel doesn't actually have an id attribute but we assume we are
+            # recieving a DMChannel or GroupChannel which inherit from PrivateChannel and do
+            return (msg.channel if isinstance(msg.channel, PrivateChannel) else msg.author.top_role).id
 
     def _verify_cache_integrity(self, current=None):
         # we want to delete all cache objects that haven't been used
diff --git a/discord/ext/commands/core.py b/discord/ext/commands/core.py
index ead83c72..e6c0ba27 100644
--- a/discord/ext/commands/core.py
+++ b/discord/ext/commands/core.py
@@ -1592,7 +1592,7 @@ def cooldown(rate, per, type=BucketType.default):
 
     A cooldown allows a command to only be used a specific amount
     of times in a specific time frame. These cooldowns can be based
-    either on a per-guild, per-channel, per-user, or global basis.
+    either on a per-guild, per-channel, per-user, per-role or global basis.
     Denoted by the third argument of ``type`` which must be of enum
     type ``BucketType`` which could be either:
 
@@ -1602,6 +1602,7 @@ def cooldown(rate, per, type=BucketType.default):
     - ``BucketType.channel`` for a per-channel basis.
     - ``BucketType.member`` for a per-member basis.
     - ``BucketType.category`` for a per-category basis.
+    - ``BucketType.role`` for a per-role basis.
 
     If a cooldown is triggered, then :exc:`.CommandOnCooldown` is triggered in
     :func:`.on_command_error` and the local error handler.