Change how some form fields are not displayed

[marien-probesys]

Problem

Some form fields are not displayed in different situations. Most of the time, it's because a collection field is empty. If we don't render these fields, Symfony generates them when calling form_end. So we mark them as rendered by calling field_name(form.field) in a HTML comment. This is pretty hacky, and not robust.

Solution

Replace all the <!-- field_name(form.field) --> by {% do form.field.setRendered %}