Merge remote-tracking branch 'upstream/asyncio' into asyncio

telethon/network/mtproto_sender.py

@@ -81,6 +81,9 @@ class MtProtoSender:
             message = messages[0]
         else:
             message = TLMessage(self.session, MessageContainer(messages))
+            # On bad_msg_salt errors, Telegram will reply with the ID of
+            # the container and not the requests it contains, so in case
+            # this happens we need to know to which container they belong.
             for m in messages:
                 m.container_msg_id = message.msg_id
 
@@ -261,7 +264,12 @@ class MtProtoSender:
             return self._pending_receive.pop(msg_id).request
 
     def _pop_requests_of_container(self, container_msg_id):
-        msgs = [msg for msg in self._pending_receive.values() if msg.container_msg_id == container_msg_id]
+        """Pops the pending requests (plural) from self._pending_receive if
+           they were sent on a container that matches container_msg_id.
+        """
+        msgs = [msg for msg in self._pending_receive.values()
+                if msg.container_msg_id == container_msg_id]
+
         requests = [msg.request for msg in msgs]
         for msg in msgs:
             self._pending_receive.pop(msg.msg_id, None)
@@ -273,12 +281,17 @@ class MtProtoSender:
         self._pending_receive.clear()
 
     async def _resend_request(self, msg_id):
+        """Re-sends the request that belongs to a certain msg_id. This may
+           also be the msg_id of a container if they were sent in one.
+        """
         request = self._pop_request(msg_id)
         if request:
+            self._logger.debug('Resending request')
             await self.send(request)
             return
         requests = self._pop_requests_of_container(msg_id)
         if requests:
+            self._logger.debug('Resending container of requests')
             await self.send(*requests)
 
     async def _handle_pong(self, msg_id, sequence, reader):
@@ -322,6 +335,8 @@ class MtProtoSender:
         )[0]
         self.session.save()
 
+        # "the bad_server_salt response is received with the
+        # correct salt, and the message is to be re-sent with it"
         await self._resend_request(bad_salt.bad_msg_id)
 
         return True