Handle zwave_js metadata/value updates when the unit changes (#63579)

* Handle zwave_js metadata updates when the unit changes

* Use value updated event instead of metadata updated event so we don't get an invalid state value

* update comments and formatting

* simplify

* Update tests/components/zwave_js/test_sensor.py

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

* Update tests/components/zwave_js/test_sensor.py

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

* Update tests/components/zwave_js/test_sensor.py

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

* fix tests

* add additional assertions

* Add unit checks and simplify logic

* Add unit assertion

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

homeassistant/components/zwave_js/sensor.py

@@ -56,7 +56,10 @@ from .const import (
     SERVICE_RESET_METER,
 )
 from .discovery import ZwaveDiscoveryInfo
-from .discovery_data_template import NumericSensorDataTemplateData
+from .discovery_data_template import (
+    NumericSensorDataTemplate,
+    NumericSensorDataTemplateData,
+)
 from .entity import ZWaveBaseEntity
 from .helpers import get_device_id
 
@@ -296,6 +299,15 @@ class ZWaveStringSensor(ZwaveSensorBase):
 class ZWaveNumericSensor(ZwaveSensorBase):
     """Representation of a Z-Wave Numeric sensor."""
 
+    @callback
+    def on_value_update(self) -> None:
+        """Handle scale changes for this value on value updated event."""
+        self._attr_native_unit_of_measurement = (
+            NumericSensorDataTemplate()
+            .resolve_data(self.info.primary_value)
+            .unit_of_measurement
+        )
+
     @property
     def native_value(self) -> float:
         """Return state of the sensor."""

tests/components/zwave_js/test_sensor.py

@@ -358,3 +358,65 @@ async def test_special_meters(hass, aeon_smart_switch_6_state, client, integrati
     assert state
     assert ATTR_DEVICE_CLASS not in state.attributes
     assert state.attributes[ATTR_STATE_CLASS] is SensorStateClass.MEASUREMENT
+
+
+async def test_unit_change(hass, zp3111, client, integration):
+    """Test unit change via metadata updated event is handled by numeric sensors."""
+    entity_id = "sensor.4_in_1_sensor_air_temperature"
+    state = hass.states.get(entity_id)
+    assert state
+    assert state.state == "21.98"
+    assert state.attributes[ATTR_UNIT_OF_MEASUREMENT] == TEMP_CELSIUS
+    event = Event(
+        "metadata updated",
+        {
+            "source": "node",
+            "event": "metadata updated",
+            "nodeId": zp3111.node_id,
+            "args": {
+                "commandClassName": "Multilevel Sensor",
+                "commandClass": 49,
+                "endpoint": 0,
+                "property": "Air temperature",
+                "metadata": {
+                    "type": "number",
+                    "readable": True,
+                    "writeable": False,
+                    "label": "Air temperature",
+                    "ccSpecific": {"sensorType": 1, "scale": 1},
+                    "unit": "°F",
+                },
+                "propertyName": "Air temperature",
+                "nodeId": zp3111.node_id,
+            },
+        },
+    )
+    zp3111.receive_event(event)
+    await hass.async_block_till_done()
+    state = hass.states.get(entity_id)
+    assert state
+    assert state.state == "21.98"
+    assert state.attributes[ATTR_UNIT_OF_MEASUREMENT] == TEMP_CELSIUS
+    event = Event(
+        "value updated",
+        {
+            "source": "node",
+            "event": "value updated",
+            "nodeId": zp3111.node_id,
+            "args": {
+                "commandClassName": "Multilevel Sensor",
+                "commandClass": 49,
+                "endpoint": 0,
+                "property": "Air temperature",
+                "newValue": 212,
+                "prevValue": 21.98,
+                "propertyName": "Air temperature",
+            },
+        },
+    )
+    zp3111.receive_event(event)
+    await hass.async_block_till_done()
+    state = hass.states.get(entity_id)
+    assert state
+    assert state.state == "100.0"
+    assert state.attributes[ATTR_UNIT_OF_MEASUREMENT] == TEMP_CELSIUS