Fix last_reported_timestamp not being updated when last_reported is changed (#118341)

* Reduce number of calls to last_reported_timestamp

When a state is created, last_update is always the same
as last_reported, and we only update it later if it changes
so we can pre-set the cached property to avoid it being
run when the recorder accesses it later.

* fix cache not being overridden

* coverage

homeassistant/core.py

@@ -1803,9 +1803,16 @@ class State:
         # The recorder or the websocket_api will always call the timestamps,
         # so we will set the timestamp values here to avoid the overhead of
         # the function call in the property we know will always be called.
-        self.last_updated_timestamp = self.last_updated.timestamp()
-        if self.last_changed == self.last_updated:
-            self.__dict__["last_changed_timestamp"] = self.last_updated_timestamp
+        last_updated = self.last_updated
+        last_updated_timestamp = last_updated.timestamp()
+        self.last_updated_timestamp = last_updated_timestamp
+        if self.last_changed == last_updated:
+            self.__dict__["last_changed_timestamp"] = last_updated_timestamp
+        # If last_reported is the same as last_updated async_set will pass
+        # the same datetime object for both values so we can use an identity
+        # check here.
+        if self.last_reported is last_updated:
+            self.__dict__["last_reported_timestamp"] = last_updated_timestamp
 
     @cached_property
     def name(self) -> str:
@@ -1822,8 +1829,6 @@ class State:
     @cached_property
     def last_reported_timestamp(self) -> float:
         """Timestamp of last report."""
-        if self.last_reported == self.last_updated:
-            return self.last_updated_timestamp
         return self.last_reported.timestamp()
 
     @cached_property
@@ -2282,6 +2287,7 @@ class StateMachine:
             # mypy does not understand this is only possible if old_state is not None
             old_last_reported = old_state.last_reported  # type: ignore[union-attr]
             old_state.last_reported = now  # type: ignore[union-attr]
+            old_state.last_reported_timestamp = timestamp  # type: ignore[union-attr]
             self._bus.async_fire_internal(
                 EVENT_STATE_REPORTED,
                 {

tests/test_core.py

@@ -3524,3 +3524,18 @@ async def test_set_time_zone_deprecated(hass: HomeAssistant) -> None:
         ),
     ):
         await hass.config.set_time_zone("America/New_York")
+
+
+async def test_async_set_updates_last_reported(hass: HomeAssistant) -> None:
+    """Test async_set method updates last_reported AND last_reported_timestamp."""
+    hass.states.async_set("light.bowl", "on", {})
+    state = hass.states.get("light.bowl")
+    last_reported = state.last_reported
+    last_reported_timestamp = state.last_reported_timestamp
+
+    for _ in range(2):
+        hass.states.async_set("light.bowl", "on", {})
+        assert state.last_reported != last_reported
+        assert state.last_reported_timestamp != last_reported_timestamp
+        last_reported = state.last_reported
+        last_reported_timestamp = state.last_reported_timestamp