Call plugin's installed() method upon event creation (#2089)

Co-authored-by: Raphael Michel <mail@raphaelmichel.de>

src/pretix/base/models/event.py

@@ -637,6 +637,11 @@ class Event(EventMixin, LoggedModel):
             Quota,
         )
 
+        #  Note: avoid self.set_active_plugins(), it causes trouble e.g. for the badges plugin.
+        #  Plugins can create data in installed() hook based on existing data of the event.
+        #  Calling set_active_plugins() results in defaults being created while actually data
+        #  should come from the copied event. Instead plugins should use event_copy_data to move
+        #  over their data.
         self.plugins = other.plugins
         self.is_public = other.is_public
         if other.date_admission:

src/pretix/control/views/event.py

@@ -1402,7 +1402,7 @@ class QuickSetupView(FormView):
             })
             quota.items.add(*items)
 
-        self.request.event.plugins = ",".join(plugins_active)
+        self.request.event.set_active_plugins(plugins_active, allow_restricted=True)
         self.request.event.save()
         messages.success(self.request, _('Your changes have been saved. You can now go on with looking at the details '
                                          'or take your event live to start selling!'))

src/pretix/control/views/main.py

@@ -251,7 +251,7 @@ class EventWizard(SafeSessionWizardView):
         with transaction.atomic(), language(basics_data['locale']):
             event = form_dict['basics'].instance
             event.organizer = foundation_data['organizer']
-            event.plugins = settings.PRETIX_PLUGINS_DEFAULT
+            event.set_active_plugins(settings.PRETIX_PLUGINS_DEFAULT.split(","), allow_restricted=True)
             event.has_subevents = foundation_data['has_subevents']
             event.testmode = True
             form_dict['basics'].save()