Add support for HomeKit CO2 sensors (#25603)

tests/components/homekit_controller/test_sensor.py

@@ -4,6 +4,7 @@ from tests.components.homekit_controller.common import FakeService, setup_test_c
 TEMPERATURE = ("temperature", "temperature.current")
 HUMIDITY = ("humidity", "relative-humidity.current")
 LIGHT_LEVEL = ("light", "light-level.current")
+CARBON_DIOXIDE_LEVEL = ("carbon-dioxide", "carbon-dioxide.level")
 
 
 def create_temperature_sensor_service():
@@ -36,6 +37,16 @@ def create_light_level_sensor_service():
     return service
 
 
+def create_carbon_dioxide_level_sensor_service():
+    """Define carbon dioxide level characteristics."""
+    service = FakeService("public.hap.service.sensor.carbon-dioxide")
+
+    cur_state = service.add_characteristic("carbon-dioxide.level")
+    cur_state.value = 0
+
+    return service
+
+
 async def test_temperature_sensor_read_state(hass, utcnow):
     """Test reading the state of a HomeKit temperature sensor accessory."""
     sensor = create_temperature_sensor_service()
@@ -76,3 +87,17 @@ async def test_light_level_sensor_read_state(hass, utcnow):
     helper.characteristics[LIGHT_LEVEL].value = 20
     state = await helper.poll_and_get_state()
     assert state.state == "20"
+
+
+async def test_carbon_dioxide_level_sensor_read_state(hass, utcnow):
+    """Test reading the state of a HomeKit carbon dioxide sensor accessory."""
+    sensor = create_carbon_dioxide_level_sensor_service()
+    helper = await setup_test_component(hass, [sensor], suffix="co2")
+
+    helper.characteristics[CARBON_DIOXIDE_LEVEL].value = 10
+    state = await helper.poll_and_get_state()
+    assert state.state == "10"
+
+    helper.characteristics[CARBON_DIOXIDE_LEVEL].value = 20
+    state = await helper.poll_and_get_state()
+    assert state.state == "20"