Add Channel.overwrites_for function to get allow/deny pairs.

1 files changed, 31 insertions, 0 deletions

diff --git a/discord/channel.py b/discord/channel.py
index b63a27c8..8353b1ba 100644
--- a/discord/channel.py
+++ b/discord/channel.py
@@ -29,8 +29,11 @@ from .permissions import Permissions
 from .enums import ChannelType
 from collections import namedtuple
 from .mixins import Hashable
+from .role import Role
+from .member import Member
 
 Overwrites = namedtuple('Overwrites', 'id allow deny type')
+PermissionOverwrite = namedtuple('PermissionOverwrite', 'allow deny')
 
 class Channel(Hashable):
     """Represents a Discord server channel.
@@ -151,6 +154,34 @@ class Channel(Hashable):
         """Returns the channel's creation time in UTC."""
         return utils.snowflake_time(self.id)
 
+    def overwrites_for(self, obj):
+        """Returns a namedtuple that gives you the channel-specific overwrites
+        for a member or a role.
+
+        The named tuple is a tuple of (allow, deny) :class:`Permissions`
+        with the appropriately named entries.
+
+        Parameters
+        -----------
+        obj
+            The :class:`Role` or :class:`Member` or :class:`Object` denoting
+            whose overwrite to get.
+        """
+
+        if isinstance(obj, Member):
+            predicate = lambda p: p.type == 'member'
+        elif isinstance(obj, Role):
+            predicate = lambda p: p.type == 'role'
+        else:
+            predicate = lambda p: True
+
+        for overwrite in filter(predicate, self._permission_overwrites):
+            if overwrite.id == obj.id:
+                return PermissionOverwrite(allow=Permissions(overwrite.allow),
+                                           deny=Permissions(overwrite.deny))
+
+        return PermissionOverwrite(allow=Permissions.none(), deny=Permissions.none())
+
     def permissions_for(self, member):
         """Handles permission resolution for the current :class:`Member`.