Vouchers: fix code min-length check on bulk creation

src/pretix/control/forms/vouchers.py

@@ -395,6 +395,15 @@ class VoucherBulkForm(VoucherForm):
 
             codes_seen = set()
             for c in data['codes']:
+                if len(c) < 5:
+                    raise ValidationError({
+                        'codes': [
+                            _('The voucher code {code} ist too short. Make sure all voucher codes are at least {min_length} characters long.').format(
+                                code=c,
+                                min_length=5
+                            )
+                        ]
+                    })
                 if c in codes_seen:
                     raise ValidationError(_('The voucher code {code} appears in your list twice.').format(code=c))
                 codes_seen.add(c)

src/tests/control/test_vouchers.py

@@ -477,6 +477,10 @@ class VoucherFormTest(SoupTestMixin, TransactionTestCase):
         self._create_bulk_vouchers({
             'codes': 'ABCDE\nDEFGH\nIJKLM\nNOPQR\nSTUVW\nXYZ',
             'itemvar': '%d' % self.ticket.pk,
+        }, expected_failure=True)
+        self._create_bulk_vouchers({
+            'codes': 'ABCDE\nDEFGH\nIJKLM\nNOPQR\nSTUVW',
+            'itemvar': '%d' % self.ticket.pk,
         })
 
     def test_create_blocking_bulk_quota_full(self):