forloop.parentloop unsupported

[trevorlacey-msft]

The forloop.parentloop object is not supported. Liquid documentation here.

Example:

List of countries:
{%- for continent in world.continents -%}
  {%- for country in continent.countries -%}
    {{ country.name }}{% unless forloop.last and forloop.parentloop.last %},{% endunless %}
  {%- endfor -%}
{%- endfor -%}

Expected:
List of countries:canada,united states,mexico,guatemala,hondura,nicaragua,el salvador,costa rica,panama,belize

Actual:
List of countries:canada,united states,mexico,guatemala,hondura,nicaragua,el salvador,costa rica,panama,belize, (trailing comma)

Issue:
forloop.parentloop always returns nil, so forloop.parentloop.last statement is always evaluated as false.