Make voucher code in notification clickable (#1423)

* Make voucher code in notification clickable

* Move html out of translated string

src/pretix/control/forms/vouchers.py

@@ -179,9 +179,7 @@ class VoucherForm(I18nModelForm):
         return data
 
     def save(self, commit=True):
-        super().save(commit)
-
-        return ['item']
+        return super().save(commit)
 
 
 class VoucherBulkForm(VoucherForm):

src/pretix/control/views/vouchers.py

@@ -12,6 +12,7 @@ from django.http import (
 from django.shortcuts import redirect, render
 from django.urls import resolve, reverse
 from django.utils.functional import cached_property
+from django.utils.html import format_html
 from django.utils.translation import ugettext_lazy as _
 from django.views.generic import (
     CreateView, DeleteView, ListView, TemplateView, UpdateView, View,
@@ -240,8 +241,15 @@ class VoucherCreate(EventPermissionRequiredMixin, CreateView):
     @transaction.atomic
     def form_valid(self, form):
         form.instance.event = self.request.event
-        messages.success(self.request, _('The new voucher has been created: {code}').format(code=form.instance.code))
         ret = super().form_valid(form)
+        url = reverse('control:event.voucher', kwargs={
+            'organizer': self.request.event.organizer.slug,
+            'event': self.request.event.slug,
+            'voucher': self.object.pk
+        })
+        messages.success(self.request, _('The new voucher has been created: {code}').format(
+            code=format_html('<a href="{url}">{code}</a>', url=url, code=self.object.code)
+        ))
         form.instance.log_action('pretix.voucher.added', data=dict(form.cleaned_data), user=self.request.user)
         return ret