total_increasing sensor with last_reset crashes entity creation (electricity_co2_emissions_daily)

[baub26]

The electricity_co2_emissions_daily sensor is created with state_class: total_increasing but also sets last_reset, which Home Assistant explicitly forbids for any state_class other than total. This raises a ValueError during entity creation, which appears to prevent subsequent sensors (cost, HP/HC breakdown) from being added in the same batch.

Traceback
Error adding entity sensor.hellowatt_PDL_electricity_co2_emissions_daily for domain sensor with platform hellowatt

Traceback (most recent call last):
File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 725, in _async_add_entities
await self._async_add_entity(
entity, False, entity_registry, config_subentry_id
)
File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 1104, in _async_add_entity
await entity.add_to_platform_finish()
File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 1446, in add_to_platform_finish
self.async_write_ha_state()
~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 1061, in async_write_ha_state
self._async_write_ha_state()
~~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 1213, in _async_write_ha_state
) = self.__async_calculate_state()
~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 1121, in __async_calculate_state
if state_attributes := self.state_attributes:
^^^^^^^^^^^^^^^^^^^^^
File "/usr/src/homeassistant/homeassistant/components/sensor/init.py", line 473, in state_attributes
raise ValueError(
...<7 lines>...
)
ValueError: Entity sensor.hellowatt_PDL_electricity_co2_emissions_daily (<class 'custom_components.hellowatt.sensor.HelloWattSensor'>) with state_class total_increasing has set last_reset. Setting last_reset for entities with state_class other than 'total' is not supported. Please update your configuration if state_class is manually configured.

Impact observed

After setup, only these sensors were successfully created for my PDL:

electricity_daily
electricity_day_before
electricity_weekly
temperature
contract_provider / contract_offer (diagnostic)

None of the cost sensors (electricity_cost_daily, electricity_cost_consumption_daily, electricity_cost_subscription_daily) or the HP/HC breakdown sensors (electricity_peak_hours_daily, electricity_off_peak_hours_daily) were created, even though:

My contract is a dual-rate (HP/HC) contract with both prices configured on HelloWatt (0.176 €/kWh HP, 0.1361 €/kWh HC, 19.84 €/month subscription)
These fields are correctly displayed on the HelloWatt website/app for this PDL

I suspect the CO2 sensor crash interrupts the rest of the sensor batch creation for this PDL, since the sensors listed after electricity_co2_emissions_daily in the README's table (cost + HP/HC) are exactly the ones missing.

Suggested fix

In sensor.py, for electricity_co2_emissions_daily (and the gas equivalent gas_co2_emissions_daily if it has the same pattern): either change state_class to total to match the last_reset usage, or remove the last_reset assignment if total_increasing is intentional.

Environment
Home Assistant Core (latest, as of August 2026)
hellowatt_hass v1.0.0 (manual install, not via HACS)
Dual-rate (HP/HC) electricity contract, no gas contract