Fix registration detail view for registrations without invoices

aleksis/apps/paweljong/templates/paweljong/event_registration/full.html

@@ -238,6 +238,7 @@
     </div>
   </div>
 
+  {% if invoice %}
   <h5>{% trans "Invoice details" %}</h5>
   <div class="col s12 m8">
     <div class="row">
@@ -318,6 +319,7 @@
       </div>
     </div>
   </div>
+  {% endif %}
 
   {% if registration.person.guardians.all %}
   <h5>{% trans "Guardians / Parents "%}</h5>

aleksis/apps/paweljong/views.py

@@ -219,8 +219,9 @@ class EventRegistrationDetailView(PermissionRequiredMixin, DetailView):
     def get_context_data(self, *args, **kwargs):
         context = super().get_context_data(*args, **kwargs)
 
-        invoice = self.get_object().get_invoice()
-        context["invoice"] = invoice
+        if self.get_object().event.max_cost is None or self.get_object().event.max_cost > 0:
+            invoice = self.get_object().get_invoice()
+            context["invoice"] = invoice
 
         return context