agendas: fix snapshot on role update (#87751)

chrono/manager/views.py

@@ -1353,6 +1353,7 @@ class AgendaEditView(ManagedAgendaMixin, UpdateView):
 
     def form_valid(self, *args, **kwargs):
         response = super().form_valid(*args, **kwargs)
+        self.agenda = Agenda.objects.get(pk=self.agenda.pk)  # refresh object, for M2M
         self.agenda.take_snapshot(request=self.request, comment=self.comment)
         return response
 

tests/manager/test_all.py

@@ -478,6 +478,8 @@ def test_add_agenda_and_set_role(app, admin_user, manager_user):
     resp = resp.form.submit().follow()
     assert 'Edit Role: Managers' in resp.text
     assert AgendaSnapshot.objects.count() == 2
+    snapshot = AgendaSnapshot.objects.latest('pk')
+    assert snapshot.serialization['permissions'] == {'edit': 'Managers', 'view': None}
 
     # still only one desk
     assert agenda.desk_set.count() == 1