Undefined method `ancestors' for nil:NilClass

[artur-deluca]

Every time we ought to generate the bundle, this error appears relating to the specific code snippet, present in any of the talk posts:

    {% if page.medium == "jupyter" %}
        {% include jupyter.html link=page.link %}
    {% elsif page.medium == "gslides" %}
        {% include gslides.html link=page.link %}
    {% else %}
        {% include nodata.html %}
    {% endif %}
</div>

As I've already checked, everything seems to be in order with jekyll or liquid (to be more specific). But I still get the same error. For instance:

Error: A Liquid tag in the excerpt of _posts/2018-10-28-Dev-Set.markdown couldn't be parsed.
Error: could not read file ./geia-ufsc.github.io/_posts/2018-10-28-Dev-Set.markdown: undefined method `ancestors' for nil:NilClass

[artur-deluca]

https://stackoverflow.com/questions/56461242/jekyll-error-undefined-method-ancestors-for-nilnilclass