Ensure mqtt sensor unit of measurement validation for state class measurement_angle (#145648)

homeassistant/components/mqtt/config_flow.py

@@ -39,6 +39,7 @@ from homeassistant.components.light import (
 from homeassistant.components.sensor import (
     CONF_STATE_CLASS,
     DEVICE_CLASS_UNITS,
+    STATE_CLASS_UNITS,
     SensorDeviceClass,
     SensorStateClass,
 )
@@ -640,6 +641,13 @@ def validate_sensor_platform_config(
     ):
         errors[CONF_UNIT_OF_MEASUREMENT] = "invalid_uom"
 
+    if (
+        (state_class := config.get(CONF_STATE_CLASS)) is not None
+        and state_class in STATE_CLASS_UNITS
+        and config.get(CONF_UNIT_OF_MEASUREMENT) not in STATE_CLASS_UNITS[state_class]
+    ):
+        errors[CONF_UNIT_OF_MEASUREMENT] = "invalid_uom_for_state_class"
+
     return errors
 
 
@@ -676,11 +684,19 @@ class PlatformField:
 @callback
 def unit_of_measurement_selector(user_data: dict[str, Any | None]) -> Selector:
     """Return a context based unit of measurement selector."""
+
+    if (state_class := user_data.get(CONF_STATE_CLASS)) in STATE_CLASS_UNITS:
+        return SelectSelector(
+            SelectSelectorConfig(
+                options=[str(uom) for uom in STATE_CLASS_UNITS[state_class]],
+                sort=True,
+                custom_value=True,
+            )
+        )
+
     if (
-        user_data is None
+        device_class := user_data.get(CONF_DEVICE_CLASS)
-        or (device_class := user_data.get(CONF_DEVICE_CLASS)) is None
+    ) is None or device_class not in DEVICE_CLASS_UNITS:
-        or device_class not in DEVICE_CLASS_UNITS
-    ):
         return TEXT_SELECTOR
     return SelectSelector(
         SelectSelectorConfig(

homeassistant/components/mqtt/sensor.py

@@ -14,6 +14,7 @@ from homeassistant.components.sensor import (
     DEVICE_CLASS_UNITS,
     DEVICE_CLASSES_SCHEMA,
     ENTITY_ID_FORMAT,
+    STATE_CLASS_UNITS,
     STATE_CLASSES_SCHEMA,
     RestoreSensor,
     SensorDeviceClass,
@@ -117,6 +118,17 @@ def validate_sensor_state_and_device_class_config(config: ConfigType) -> ConfigT
                 f"got `{CONF_DEVICE_CLASS}` '{device_class}'"
             )
 
+    if (
+        (state_class := config.get(CONF_STATE_CLASS)) is not None
+        and state_class in STATE_CLASS_UNITS
+        and (unit_of_measurement := config.get(CONF_UNIT_OF_MEASUREMENT))
+        not in STATE_CLASS_UNITS[state_class]
+    ):
+        raise vol.Invalid(
+            f"The unit of measurement '{unit_of_measurement}' is not valid "
+            f"together with state class '{state_class}'"
+        )
+
     if (device_class := config.get(CONF_DEVICE_CLASS)) is None or (
         unit_of_measurement := config.get(CONF_UNIT_OF_MEASUREMENT)
     ) is None:

homeassistant/components/mqtt/strings.json

@@ -644,6 +644,7 @@
         "invalid_template": "Invalid template",
         "invalid_supported_color_modes": "Invalid supported color modes selection",
         "invalid_uom": "The unit of measurement \"{unit_of_measurement}\" is not supported by the selected device class, please either remove the device class, select a device class which supports \"{unit_of_measurement}\", or pick a supported unit of measurement from the list",
+        "invalid_uom_for_state_class": "The unit of measurement \"{unit_of_measurement}\" is not supported by the selected state class, please either remove the state class, select a state class which supports \"{unit_of_measurement}\", or pick a supported unit of measurement from the list",
         "invalid_url": "Invalid URL",
         "last_reset_not_with_state_class_total": "The last reset value template option should be used with state class 'Total' only",
         "max_below_min_kelvin": "Max Kelvin value should be greater than min Kelvin value",

tests/components/mqtt/test_config_flow.py

@@ -3038,7 +3038,15 @@ async def test_migrate_of_incompatible_config_entry(
             {
                 "state_class": "measurement",
             },
-            (),
+            (
+                (
+                    {
+                        "state_class": "measurement_angle",
+                        "unit_of_measurement": "deg",
+                    },
+                    {"unit_of_measurement": "invalid_uom_for_state_class"},
+                ),
+            ),
             {
                 "state_topic": "test-topic",
             },

tests/components/mqtt/test_sensor.py

@@ -995,6 +995,32 @@ async def test_invalid_state_class(
     assert "expected SensorStateClass or one of" in caplog.text
 
 
+@pytest.mark.parametrize(
+    "hass_config",
+    [
+        {
+            mqtt.DOMAIN: {
+                sensor.DOMAIN: {
+                    "name": "test",
+                    "state_topic": "test-topic",
+                    "state_class": "measurement_angle",
+                    "unit_of_measurement": "deg",
+                }
+            }
+        }
+    ],
+)
+async def test_invalid_state_class_with_unit_of_measurement(
+    mqtt_mock_entry: MqttMockHAClientGenerator, caplog: pytest.LogCaptureFixture
+) -> None:
+    """Test state_class option with invalid unit of measurement."""
+    assert await mqtt_mock_entry()
+    assert (
+        "The unit of measurement 'deg' is not valid together with state class 'measurement_angle'"
+        in caplog.text
+    )
+
+
 @pytest.mark.parametrize(
     ("hass_config", "error_logged"),
     [