Allow closest() to return the zone closest to a person

[harmpter]

Describe the enhancement

I'd like to use closest('person.paul', states.zone) to show the zone that is closest to my current location.
This doesn't work yet because the second argument of closest() is always expanded, so HA doesn't consider any zone entities, but instead considers the entities within those zones (eg persons, because they have location data)

I found it on this line: https://github.com/home-assistant/core/blob/8a74b41db55d4a8eb3f053dcf1319c2b34e939e9/homeassistant/helpers/template/__init__.py#L737

Maybe we can skip expanding for zones? I don't know. What do you think?

Example usage

Examples: 

{{ closest('person.paul', states.zone) }}


{% set gyms = states.zone|selectattr('entity_id','contains','zone.gym_') %}
{{ closest('person.paul',gyms) }}

Current workarounds

{% macro closest_zone(entity,zones) -%}
  {% set ns = namespace(closest_zone=None,closest_distance=float('inf')) -%}
  {% for z in zones -%}
    {% set d = distance(z,entity) -%}
    {% if d < ns.closest_distance -%}
      {% set  ns.closest_distance = d -%}{% set ns.closest_zone = z -%}
    {% endif -%}
  {% endfor -%}
  {{ ns.closest_zone.entity_id -}}
{% endmacro -%}

Anything else?

No response

[cookesan]

The behavior comes from closest() calling expand() on the entity argument before it calls the location helper.

In the template helper source, expand() explicitly expands groups and zones into their member entities. Then closest() passes the expanded result into loc_helper.closest(...). That means states.zone is not treated as "the zone entities to compare"; it becomes "the entities inside those zones."

So the feature request makes sense, but I would avoid changing expand() globally. Other templates may rely on zones expanding that way. A narrower change would be for closest() to preserve zone state objects when the caller supplied zone entities, or to add a separate helper/filter path for "closest zone" that does not expand zones into their occupants.

[harmpter]

Yes, thank you for rephrasing. I want to clarify: by

Maybe we can skip expanding for zones?

I meant a change in L737 (link in OP), not changing expand 😅