Link to destroy action of the file object

app/views/exercises/_file_form.html.slim

@@ -7,7 +7,8 @@ li.panel.panel-default
         span = f.object.name
   .panel-collapse.collapse class=('in' if f.object.name.nil?) id="collapse#{id}" role="tabpanel"
     .panel-body
-      .clearfix = link_to(t('shared.destroy'), '#', class:'btn btn-warning btn-sm discard-file pull-right')
+      - if policy(f.object).destroy?
+        .clearfix = link_to(t('shared.destroy'), f.object, class: 'btn btn-warning btn-sm pull-right', data: {confirm: t('shared.confirm_destroy')}, method: :delete)
       .form-group
         = f.label(:name, t('activerecord.attributes.file.name'))
         = f.text_field(:name, class: 'form-control')