Prefer explicit DeviceClass over hint in entity_id in homekit (#152507)

Co-authored-by: Abílio Costa <abmantis@users.noreply.github.com>

homeassistant/components/homekit/accessories.py

@@ -220,31 +220,33 @@ def get_accessory(  # noqa: C901
             a_type = "TemperatureSensor"
         elif device_class == SensorDeviceClass.HUMIDITY and unit == PERCENTAGE:
             a_type = "HumiditySensor"
-        elif (
-            device_class == SensorDeviceClass.PM10
-            or SensorDeviceClass.PM10 in state.entity_id
-        ):
+        elif device_class == SensorDeviceClass.PM10:
             a_type = "PM10Sensor"
-        elif (
-            device_class == SensorDeviceClass.PM25
-            or SensorDeviceClass.PM25 in state.entity_id
-        ):
+        elif device_class == SensorDeviceClass.PM25:
             a_type = "PM25Sensor"
         elif device_class == SensorDeviceClass.NITROGEN_DIOXIDE:
             a_type = "NitrogenDioxideSensor"
         elif device_class == SensorDeviceClass.VOLATILE_ORGANIC_COMPOUNDS:
             a_type = "VolatileOrganicCompoundsSensor"
-        elif (
-            device_class == SensorDeviceClass.GAS
-            or SensorDeviceClass.GAS in state.entity_id
-        ):
+        elif device_class == SensorDeviceClass.GAS:
             a_type = "AirQualitySensor"
         elif device_class == SensorDeviceClass.CO:
             a_type = "CarbonMonoxideSensor"
-        elif device_class == SensorDeviceClass.CO2 or "co2" in state.entity_id:
+        elif device_class == SensorDeviceClass.CO2:
             a_type = "CarbonDioxideSensor"
         elif device_class == SensorDeviceClass.ILLUMINANCE or unit == LIGHT_LUX:
             a_type = "LightSensor"
+
+        # Fallbacks based on entity_id
+        elif SensorDeviceClass.PM10 in state.entity_id:
+            a_type = "PM10Sensor"
+        elif SensorDeviceClass.PM25 in state.entity_id:
+            a_type = "PM25Sensor"
+        elif SensorDeviceClass.GAS in state.entity_id:
+            a_type = "AirQualitySensor"
+        elif "co2" in state.entity_id:
+            a_type = "CarbonDioxideSensor"
+
         else:
             _LOGGER.debug(
                 "%s: Unsupported sensor type (device_class=%s) (unit=%s)",

tests/components/homekit/test_get_accessories.py

@@ -20,6 +20,13 @@ from homeassistant.components.homekit.const import (
     TYPE_SWITCH,
     TYPE_VALVE,
 )
+from homeassistant.components.homekit.type_sensors import (
+    AirQualitySensor,
+    CarbonDioxideSensor,
+    PM10Sensor,
+    PM25Sensor,
+    TemperatureSensor,
+)
 from homeassistant.components.media_player import (
     MediaPlayerDeviceClass,
     MediaPlayerEntityFeature,
@@ -42,6 +49,20 @@ from homeassistant.const import (
 from homeassistant.core import State
 
 
+def get_identified_type(entity_id, attrs, config=None):
+    """Helper to return the accessory type name selected by get_accessory."""
+
+    def passthrough(type: type):
+        return lambda *args, **kwargs: type
+
+    # Patch TYPES so that get_accessory returns a type instead of an instance.
+    with patch.dict(
+        TYPES, {type_name: passthrough(v) for type_name, v in TYPES.items()}
+    ):
+        entity_state = State(entity_id, "irrelevant", attrs)
+        return get_accessory(None, None, entity_state, 2, config or {})
+
+
 def test_not_supported(caplog: pytest.LogCaptureFixture) -> None:
     """Test if none is returned if entity isn't supported."""
     # not supported entity
@@ -425,3 +446,58 @@ def test_type_camera(type_name, entity_id, state, attrs) -> None:
         entity_state = State(entity_id, state, attrs)
         get_accessory(None, None, entity_state, 2, {})
     assert mock_type.called
+
+
+@pytest.mark.parametrize(
+    ("expected_type", "entity_id", "attrs"),
+    [
+        (
+            PM10Sensor,
+            "sensor.air_quality_pm25",
+            {ATTR_DEVICE_CLASS: SensorDeviceClass.PM10},
+        ),
+        (
+            PM25Sensor,
+            "sensor.air_quality_pm10",
+            {ATTR_DEVICE_CLASS: SensorDeviceClass.PM25},
+        ),
+        (
+            AirQualitySensor,
+            "sensor.co2_sensor",
+            {ATTR_DEVICE_CLASS: SensorDeviceClass.GAS},
+        ),
+        (
+            CarbonDioxideSensor,
+            "sensor.air_quality_gas",
+            {ATTR_DEVICE_CLASS: SensorDeviceClass.CO2},
+        ),
+        (
+            TemperatureSensor,
+            "sensor.random_sensor",
+            {ATTR_DEVICE_CLASS: SensorDeviceClass.TEMPERATURE},
+        ),
+    ],
+)
+def test_explicit_device_class_takes_precedence(
+    expected_type, entity_id, attrs
+) -> None:
+    """Test that explicit device_class takes precedence over entity_id hints."""
+    identified_type = get_identified_type(entity_id, attrs=attrs)
+    assert identified_type == expected_type
+
+
+@pytest.mark.parametrize(
+    ("expected_type", "entity_id", "attrs"),
+    [
+        (PM10Sensor, "sensor.air_quality_pm10", {}),
+        (PM25Sensor, "sensor.air_quality_pm25", {}),
+        (AirQualitySensor, "sensor.air_quality_gas", {}),
+        (CarbonDioxideSensor, "sensor.airmeter_co2", {}),
+    ],
+)
+def test_entity_id_fallback_when_no_device_class(
+    expected_type, entity_id, attrs
+) -> None:
+    """Test that entity_id is used as fallback when device_class is not set."""
+    identified_type = get_identified_type(entity_id, attrs=attrs)
+    assert identified_type == expected_type