Preserve float precision in Powerwall charge sensor (#181991)

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

homeassistant/components/powerwall/sensor.py

@@ -286,6 +286,7 @@ class PowerWallChargeSensor(PowerWallEntity, SensorEntity):
     _attr_state_class = SensorStateClass.MEASUREMENT
     _attr_native_unit_of_measurement = PERCENTAGE
     _attr_device_class = SensorDeviceClass.BATTERY
+    _attr_suggested_display_precision = 0
 
     @property
     @override
@@ -295,9 +296,9 @@ class PowerWallChargeSensor(PowerWallEntity, SensorEntity):
 
     @property
     @override
-    def native_value(self) -> int:
+    def native_value(self) -> float:
         """Get the current value in percentage."""
-        return round(self.data.charge)
+        return self.data.charge
 
 
 class PowerWallEnergySensor(PowerWallEntity, SensorEntity):

tests/components/powerwall/test_sensor.py

@@ -32,7 +32,11 @@ from tests.common import MockConfigEntry, async_fire_time_changed
 
 
 @pytest.mark.usefixtures("entity_registry_enabled_by_default")
-async def test_sensors(hass: HomeAssistant, device_registry: dr.DeviceRegistry) -> None:
+async def test_sensors(
+    hass: HomeAssistant,
+    device_registry: dr.DeviceRegistry,
+    entity_registry: er.EntityRegistry,
+) -> None:
     """Test creation of the sensors."""
 
     mock_powerwall = await _mock_powerwall_with_fixtures(hass)
@@ -113,7 +117,10 @@ async def test_sensors(hass: HomeAssistant, device_registry: dr.DeviceRegistry)
     assert float(hass.states.get("sensor.mysite_solar_import").state) == 28.2
 
     state = hass.states.get("sensor.mysite_charge")
-    assert state.state == "47"
+    assert state.state == "47.34587394586"
+    entity_entry = entity_registry.async_get("sensor.mysite_charge")
+    assert entity_entry is not None
+    assert entity_entry.options["sensor"]["suggested_display_precision"] == 0
     expected_attributes = {
         "unit_of_measurement": PERCENTAGE,
         "friendly_name": "MySite Charge",