UnusedVariable: Variables defined inside for should not be usable outside

[sustmi]

In the current Twig documentation there is a note about variable scope defined inside for loops:

Note that loops are scoped in Twig; therefore a variable declared inside a for loop is not accessible outside the loop itself:

{% for item in list %}
    {% set foo = item %}
{% endfor %}

{# foo is NOT available #}

If you want to access the variable, just declare it before the loop:

{% set foo = "" %}
{% for item in list %}
    {% set foo = item %}
{% endfor %}

https://twig.symfony.com/doc/3.x/tags/set.html

However, when I try to run twigcs on the following code:

{% for item in list %}
    {% set foo = item %}
{% endfor %}

{{ foo }}

it does not consider foo variable inside the loop to be unused.

Steps to reproduce

I created a failing test case (that should be passing) here: https://github.com/sustmi/twigcs/blob/19819daad7900dce0f18c4569b9f9fec539cdf11/tests/Twig3FunctionalTest.php#L231

1. git clone https://github.com/sustmi/twigcs/
2. cd twigcs
3. git checkout unused-variable-issue-181
4. composer install
5. phpunit tests/Twig3FunctionalTest.php

[gnutix]

In the same vein but maybe different :

{% set was_current = false %}

{% for item in items %}
    {% if not loop.first and not was_current and not item.current %}
        {# ... #}
    {% endif %}

    {# ... #}

    {% set was_current = item.current %}
{% endfor %}

Produces an inspection for the line {% set was_current = item.current %} :

WARNING Unused variable "was_current"