I have a do_shortcut and I need to embed it in a twig template. I tried by coping the code in a php file my-code.php:
About the include
part, create a my_code.html.twig
file at app/Resources/views/my_code.html.twig and copy-paste your code from my-code.php
Then you can include that code anywhere like :
{% include 'my_code.html.twig' %}
EDIT: tested and working in symfony3
You can't do that, you should create a twig extension and transform the php function into a twig function: http://symfony.com/doc/current/cookbook/templating/twig_extension.html
Try this code:
{{ wp.do_shortcode('[shortcode]')|raw }}