ForCompiler bug

[apsavin]

We can use the following code inside twig templates: {{ loop.parent.loop.index0 }}
It works great on our server, where twig compiles into php files, but it doesn't work when we try to compile it in JavaScript.

You can fix it very easy, just replace this line with the following:

->write("'parent': {loop: loop$parentSuffix},\n")

and merge other things to the parent context.

[zmajciki]

I think that this change produced another bug with nested loop. For example, this code compiles well

{% for dd in data %}
    {{ loop.index }} {# parent loop index #}
    {% for d in dd %}
        {{ loop.index }} {# child loop index #}
    {% endfor %}
{% endfor %}    

But this one desn't:

{% for dd in data %}
    {% for d in dd %}
        {{ loop.index }} {# child loop index #}
    {% endfor %}
{% endfor %}

I think that it is because when the loop variable is used in parent for it sets its attribute "with_loop" to true and adds loop variable in JS.

When parent do not use the loop variable then parent's "with_loop" is not set so variable loop is not set, but it is used in child for.

[apsavin]

This change wasn't merged

[zmajciki]

Sorry, my bad, both lines look very similar.

Either way, bug exists, and is coused by reference to nonexisting loop variable (which does not exits if parent doesn't use loop in its body).