From e84c9847c58a6fafdce48aea67754f53f533976c Mon Sep 17 00:00:00 2001
From: Lonami Exo <totufals@hotmail.com>
Date: Wed, 1 May 2019 16:37:54 +0200
Subject: [PATCH] Use sets instead of isinstance in StateCache too

Similar reasoning to the change for EntityCache, sets are faster
than attribute lookups (into types.) and isinstance (another global
lookup). Updating the state is also very common, so it should be
as fast as possible.
---
 telethon/statecache.py | 53 ++++++++++++++++++++++++------------------
 1 file changed, 30 insertions(+), 23 deletions(-)

diff --git a/telethon/statecache.py b/telethon/statecache.py
index 27ba7d1e..bea63edd 100644
--- a/telethon/statecache.py
+++ b/telethon/statecache.py
@@ -27,7 +27,7 @@ class StateCache:
             update,
             *,
             channel_id=None,
-            has_pts=(
+            has_pts=frozenset(x.CONSTRUCTOR_ID for x in (
                 types.UpdateNewMessage,
                 types.UpdateDeleteMessages,
                 types.UpdateReadHistoryInbox,
@@ -40,8 +40,8 @@ class StateCache:
                 types.UpdateShortMessage,
                 types.UpdateShortChatMessage,
                 types.UpdateShortSentMessage
-            ),
-            has_date=(
+            )),
+            has_date=frozenset(x.CONSTRUCTOR_ID for x in (
                 types.UpdateUserPhoto,
                 types.UpdateEncryption,
                 types.UpdateEncryptedMessagesRead,
@@ -53,8 +53,8 @@ class StateCache:
                 types.UpdatesCombined,
                 types.Updates,
                 types.UpdateShortSentMessage,
-            ),
-            has_channel_pts=(
+            )),
+            has_channel_pts=frozenset(x.CONSTRUCTOR_ID for x in (
                 types.UpdateChannelTooLong,
                 types.UpdateNewChannelMessage,
                 types.UpdateDeleteChannelMessages,
@@ -63,22 +63,21 @@ class StateCache:
                 types.updates.ChannelDifferenceEmpty,
                 types.updates.ChannelDifferenceTooLong,
                 types.updates.ChannelDifference
-            )
+            ))
     ):
         """
         Update the state with the given update.
         """
-        has_pts = isinstance(update, has_pts)
-        has_date = isinstance(update, has_date)
-        has_channel_pts = isinstance(update, has_channel_pts)
-        if has_pts and has_date:
-            self._pts_date = update.pts, update.date
-        elif has_pts:
-            self._pts_date = update.pts, self._pts_date[1]
-        elif has_date:
+        cid = update.CONSTRUCTOR_ID
+        if cid in has_pts:
+            if cid in has_date:
+                self._pts_date = update.pts, update.date
+            else:
+                self._pts_date = update.pts, self._pts_date[1]
+        elif cid in has_date:
             self._pts_date = self._pts_date[0], update.date
 
-        if has_channel_pts:
+        if cid in has_channel_pts:
             if channel_id is None:
                 channel_id = self.get_channel_id(update)
 
@@ -91,20 +90,26 @@ class StateCache:
     def get_channel_id(
             self,
             update,
-            has_channel_id=(
+            has_channel_id=frozenset(x.CONSTRUCTOR_ID for x in (
                 types.UpdateChannelTooLong,
                 types.UpdateDeleteChannelMessages,
                 types.UpdateChannelWebPage
-            ),
-            has_message=(
+            )),
+            has_message=frozenset(x.CONSTRUCTOR_ID for x in (
                 types.UpdateNewChannelMessage,
                 types.UpdateEditChannelMessage
-            )
+            ))
     ):
-        # Will only fail for *difference, where channel_id is known
-        if isinstance(update, has_channel_id):
+        """
+        Gets the **unmarked** channel ID from this update, if it has any.
+
+        Fails for ``*difference`` updates, where ``channel_id``
+        is supposedly already known from the outside.
+        """
+        cid = update.CONSTRUCTOR_ID
+        if cid in has_channel_id:
             return update.channel_id
-        elif isinstance(update, has_message):
+        elif cid in has_message:
             if update.message.to_id is None:
                 self._logger.info('Update has None to_id %s', update)
             else:
@@ -114,7 +119,9 @@ class StateCache:
 
     def __getitem__(self, item):
         """
-        Gets the corresponding ``(pts, date)`` for the given ID or peer,
+        If `item` is ``None``, returns the default ``(pts, date)``.
+
+        If it's an **unmarked** channel ID, returns its ``pts``.
         """
         if item is None:
             return self._pts_date