Which is hard coded list and a hard coded template with a string, as it should?
returns:
2022-09-21 14:11:49.505 ERROR (MainThread) [homeassistant.components.light] Error while setting up template platform for light
Traceback (most recent call last):
File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 289, in _async_setup_platform
await asyncio.gather(*pending)
File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 428, in async_add_entities
await asyncio.gather(*tasks)
File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 691, in _async_add_entity
await entity.add_to_platform_finish()
File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 776, in add_to_platform_finish
await self.async_added_to_hass()
File "/usr/src/homeassistant/homeassistant/components/template/light.py", line 321, in async_added_to_hass
await super().async_added_to_hass()
File "/usr/src/homeassistant/homeassistant/helpers/template_entity.py", line 385, in async_added_to_hass
await self._async_template_startup()
File "/usr/src/homeassistant/homeassistant/helpers/template_entity.py", line 356, in _async_template_startup
result_info.async_refresh()
File "/usr/src/homeassistant/homeassistant/helpers/event.py", line 934, in async_refresh
self._refresh(None)
File "/usr/src/homeassistant/homeassistant/helpers/event.py", line 1111, in _refresh
self.hass.async_run_hass_job(self._job, event, updates)
File "/usr/src/homeassistant/homeassistant/core.py", line 567, in async_run_hass_job
hassjob.target(*args)
File "/usr/src/homeassistant/homeassistant/helpers/template_entity.py", line 321, in _handle_results
attr.handle_result(
File "/usr/src/homeassistant/homeassistant/helpers/template_entity.py", line 126, in handle_result
self.on_update(result)
File "/usr/src/homeassistant/homeassistant/components/template/light.py", line 477, in _update_effect
if effect not in self._effect_list:
TypeError: argument of type 'NoneType' is not iterable
Right, because the template watches an entity and has a resolved solution. If there’s no trigger to update the template, it doesn’t update. A template with {{ ['a','b'] }} has no entities to trigger updates. So it never resolves. I’d argue that it should attempt to resolve on startup, but that doesn’t seem to be the case.