Ensure mqtt sensor has a valid native unit of measurement (home-assistant#146722)

Author: jbouwh

homeassistant/components/mqtt/sensor.py

@@ -35,7 +35,6 @@
 from homeassistant.helpers import config_validation as cv
 from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
 from homeassistant.helpers.event import async_call_later
-from homeassistant.helpers.issue_registry import IssueSeverity, async_create_issue
 from homeassistant.helpers.service_info.mqtt import ReceivePayloadType
 from homeassistant.helpers.typing import ConfigType, VolSchemaType
 from homeassistant.util import dt as dt_util
@@ -48,7 +47,6 @@
     CONF_OPTIONS,
     CONF_STATE_TOPIC,
     CONF_SUGGESTED_DISPLAY_PRECISION,
-    DOMAIN,
     PAYLOAD_NONE,
 )
 from .entity import MqttAvailabilityMixin, MqttEntity, async_setup_entity_entry_helper
@@ -138,12 +136,9 @@ def validate_sensor_state_and_device_class_config(config: ConfigType) -> ConfigT
         device_class in DEVICE_CLASS_UNITS
         and unit_of_measurement not in DEVICE_CLASS_UNITS[device_class]
     ):
-        _LOGGER.warning(
-            "The unit of measurement `%s` is not valid "
-            "together with device class `%s`. "
-            "this will stop working in HA Core 2025.7.0",
-            unit_of_measurement,
-            device_class,
+        raise vol.Invalid(
+            f"The unit of measurement `{unit_of_measurement}` is not valid "
+            f"together with device class `{device_class}`",
         )
 
     return config
@@ -194,40 +189,8 @@ class MqttSensor(MqttEntity, RestoreSensor):
         None
     )
 
-    @callback
-    def async_check_uom(self) -> None:
-        """Check if the unit of measurement is valid with the device class."""
-        if (
-            self._discovery_data is not None
-            or self.device_class is None
-            or self.native_unit_of_measurement is None
-        ):
-            return
-        if (
-            self.device_class in DEVICE_CLASS_UNITS
-            and self.native_unit_of_measurement
-            not in DEVICE_CLASS_UNITS[self.device_class]
-        ):
-            async_create_issue(
-                self.hass,
-                DOMAIN,
-                self.entity_id,
-                issue_domain=sensor.DOMAIN,
-                is_fixable=False,
-                severity=IssueSeverity.WARNING,
-                learn_more_url=URL_DOCS_SUPPORTED_SENSOR_UOM,
-                translation_placeholders={
-                    "uom": self.native_unit_of_measurement,
-                    "device_class": self.device_class.value,
-                    "entity_id": self.entity_id,
-                },
-                translation_key="invalid_unit_of_measurement",
-                breaks_in_ha_version="2025.7.0",
-            )
-
     async def mqtt_async_added_to_hass(self) -> None:
         """Restore state for entities with expire_after set."""
-        self.async_check_uom()
         last_state: State | None
         last_sensor_data: SensorExtraStoredData | None
         if (

homeassistant/components/mqtt/strings.json

@@ -3,10 +3,6 @@
     "invalid_platform_config": {
       "title": "Invalid config found for MQTT {domain} item",
       "description": "Home Assistant detected an invalid config for a manually configured item.\n\nPlatform domain: **{domain}**\nConfiguration file: **{config_file}**\nNear line: **{line}**\nConfiguration found:\n```yaml\n{config}\n```\nError: **{error}**.\n\nMake sure the configuration is valid and [reload](/developer-tools/yaml) the manually configured MQTT items or restart Home Assistant to fix this issue."
-    },
-    "invalid_unit_of_measurement": {
-      "title": "Sensor with invalid unit of measurement",
-      "description": "Manual configured Sensor entity **{entity_id}** has a configured unit of measurement **{uom}** which is not valid with configured device class **{device_class}**. Make sure a valid unit of measurement is configured or remove the device class, and [reload](/developer-tools/yaml) the manually configured MQTT items or restart Home Assistant to fix this issue."
     }
   },
   "config": {

tests/components/mqtt/test_sensor.py

@@ -898,42 +898,12 @@ async def test_invalid_unit_of_measurement(
         "The unit of measurement `ppm` is not valid together with device class `energy`"
         in caplog.text
     )
-    # A repair issue was logged
+    # A repair issue was logged for the failing YAML config
     assert len(events) == 1
-    assert events[0].data["issue_id"] == "sensor.test"
-    # Assert the sensor works
-    async_fire_mqtt_message(hass, "test-topic", "100")
-    await hass.async_block_till_done()
+    assert events[0].data["domain"] == mqtt.DOMAIN
+    # Assert the sensor is not created
     state = hass.states.get("sensor.test")
-    assert state is not None
-    assert state.state == "100"
-
-    caplog.clear()
-
-    discovery_payload = {
-        "name": "bla",
-        "state_topic": "test-topic2",
-        "device_class": "temperature",
-        "unit_of_measurement": "C",
-    }
-    # Now discover an other invalid sensor
-    async_fire_mqtt_message(
-        hass, "homeassistant/sensor/bla/config", json.dumps(discovery_payload)
-    )
-    await hass.async_block_till_done()
-    assert (
-        "The unit of measurement `C` is not valid together with device class `temperature`"
-        in caplog.text
-    )
-    # Assert the sensor works
-    async_fire_mqtt_message(hass, "test-topic2", "21")
-    await hass.async_block_till_done()
-    state = hass.states.get("sensor.bla")
-    assert state is not None
-    assert state.state == "21"
-
-    # No new issue was registered for the discovered entity
-    assert len(events) == 1
+    assert state is None
 
 
 @pytest.mark.parametrize(