Fix sensor.time intermittent startup exception (#38525)

homeassistant/components/time_date/sensor.py

@@ -42,15 +42,9 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
         _LOGGER.error("Timezone is not set in Home Assistant configuration")
         return False
 
-    devices = []
-    for variable in config[CONF_DISPLAY_OPTIONS]:
-        device = TimeDateSensor(hass, variable)
-        async_track_point_in_utc_time(
-            hass, device.point_in_time_listener, device.get_next_interval()
-        )
-        devices.append(device)
-
-    async_add_entities(devices, True)
+    async_add_entities(
+        [TimeDateSensor(hass, variable) for variable in config[CONF_DISPLAY_OPTIONS]]
+    )
 
 
 class TimeDateSensor(Entity):
@@ -62,6 +56,7 @@ class TimeDateSensor(Entity):
         self.type = option_type
         self._state = None
         self.hass = hass
+        self.unsub = None
 
         self._update_internal_state(dt_util.utcnow())
 
@@ -84,6 +79,18 @@ class TimeDateSensor(Entity):
             return "mdi:calendar"
         return "mdi:clock"
 
+    async def async_added_to_hass(self) -> None:
+        """Set up next update."""
+        self.unsub = async_track_point_in_utc_time(
+            self.hass, self.point_in_time_listener, self.get_next_interval()
+        )
+
+    async def async_will_remove_from_hass(self) -> None:
+        """Cancel next update."""
+        if self.unsub:
+            self.unsub()
+            self.unsub = None
+
     def get_next_interval(self, now=None):
         """Compute next time an update should occur."""
         if now is None:
@@ -137,6 +144,6 @@ class TimeDateSensor(Entity):
         """Get the latest data and update state."""
         self._update_internal_state(time_date)
         self.async_write_ha_state()
-        async_track_point_in_utc_time(
+        self.unsub = async_track_point_in_utc_time(
             self.hass, self.point_in_time_listener, self.get_next_interval()
         )