From 20d5d3c162cfee32f30b602bccd0732cb0ac1529 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Tue, 14 Jul 2020 19:31:34 -1000
Subject: [PATCH] Switch a few more async_track_state_change to the faster
 async_track_state_change_event (#37833)

async_track_state_change_event is faster than async_track_state_change
and since we do not care about the data being returned to the callback
this is a simple speedup
---
 homeassistant/components/history_stats/sensor.py   |  4 ++--
 homeassistant/components/switch/light.py           | 14 ++++++--------
 homeassistant/components/websocket_api/commands.py |  4 ++--
 3 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/homeassistant/components/history_stats/sensor.py b/homeassistant/components/history_stats/sensor.py
index 48d65145219..2c77261d344 100644
--- a/homeassistant/components/history_stats/sensor.py
+++ b/homeassistant/components/history_stats/sensor.py
@@ -20,7 +20,7 @@ from homeassistant.core import callback
 from homeassistant.exceptions import TemplateError
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity
-from homeassistant.helpers.event import async_track_state_change
+from homeassistant.helpers.event import async_track_state_change_event
 import homeassistant.util.dt as dt_util
 
 _LOGGER = logging.getLogger(__name__)
@@ -128,7 +128,7 @@ class HistoryStatsSensor(Entity):
                 self.async_schedule_update_ha_state(True)
 
             force_refresh()
-            async_track_state_change(self.hass, self._entity_id, force_refresh)
+            async_track_state_change_event(self.hass, [self._entity_id], force_refresh)
 
         # Delay first refresh to keep startup fast
         hass.bus.listen_once(EVENT_HOMEASSISTANT_START, start_refresh)
diff --git a/homeassistant/components/switch/light.py b/homeassistant/components/switch/light.py
index c23390a3e3e..8b751871014 100644
--- a/homeassistant/components/switch/light.py
+++ b/homeassistant/components/switch/light.py
@@ -1,6 +1,6 @@
 """Light support for switch entities."""
 import logging
-from typing import Callable, Optional, Sequence, cast
+from typing import Any, Callable, Optional, Sequence, cast
 
 import voluptuous as vol
 
@@ -13,10 +13,10 @@ from homeassistant.const import (
     STATE_ON,
     STATE_UNAVAILABLE,
 )
-from homeassistant.core import CALLBACK_TYPE, State, callback
+from homeassistant.core import CALLBACK_TYPE, callback
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity
-from homeassistant.helpers.event import async_track_state_change
+from homeassistant.helpers.event import async_track_state_change_event
 from homeassistant.helpers.typing import (
     ConfigType,
     DiscoveryInfoType,
@@ -117,15 +117,13 @@ class LightSwitch(LightEntity):
         """Register callbacks."""
 
         @callback
-        def async_state_changed_listener(
-            entity_id: str, old_state: State, new_state: State
-        ) -> None:
+        def async_state_changed_listener(*_: Any) -> None:
             """Handle child updates."""
             self.async_schedule_update_ha_state(True)
 
         assert self.hass is not None
-        self._async_unsub_state_changed = async_track_state_change(
-            self.hass, self._switch_entity_id, async_state_changed_listener
+        self._async_unsub_state_changed = async_track_state_change_event(
+            self.hass, [self._switch_entity_id], async_state_changed_listener
         )
 
     async def async_will_remove_from_hass(self):
diff --git a/homeassistant/components/websocket_api/commands.py b/homeassistant/components/websocket_api/commands.py
index 3de41bc8918..d7e2fa1ac83 100644
--- a/homeassistant/components/websocket_api/commands.py
+++ b/homeassistant/components/websocket_api/commands.py
@@ -8,7 +8,7 @@ from homeassistant.const import EVENT_STATE_CHANGED, EVENT_TIME_CHANGED, MATCH_A
 from homeassistant.core import DOMAIN as HASS_DOMAIN, callback
 from homeassistant.exceptions import HomeAssistantError, ServiceNotFound, Unauthorized
 from homeassistant.helpers import config_validation as cv
-from homeassistant.helpers.event import async_track_state_change
+from homeassistant.helpers.event import async_track_state_change_event
 from homeassistant.helpers.service import async_get_all_descriptions
 from homeassistant.loader import IntegrationNotFound, async_get_integration
 
@@ -255,7 +255,7 @@ def handle_render_template(hass, connection, msg):
         )
 
     if entity_ids and entity_ids != MATCH_ALL:
-        connection.subscriptions[msg["id"]] = async_track_state_change(
+        connection.subscriptions[msg["id"]] = async_track_state_change_event(
             hass, entity_ids, state_listener
         )
     else: