actually create the 0% tax rate

(Still warn if tax rate is not filled at all)

src/pretix/base/payment.py

@@ -957,19 +957,12 @@ class BasePaymentProvider:
 
     def cancel_payment(self, payment: OrderPayment):
         """
-        Will be called to cancel a payment. The default implementation fails if the payment is
-        ``OrderPayment.PAYMENT_STATE_PENDING`` and ``abort_pending_allowed`` is false. Otherwise, it just sets the
-        payment state to canceled. In some cases you might want to modify this behaviour to notify the external provider
-        of the cancellation.
+        Will be called to cancel a payment. The default implementation just sets the payment state to canceled,
+        but in some cases you might want to notify an external provider.
 
         On success, you should set ``payment.state = OrderPayment.PAYMENT_STATE_CANCELED`` (or call the super method).
         On failure, you should raise a PaymentException.
         """
-        if payment.state == OrderPayment.PAYMENT_STATE_PENDING and not self.abort_pending_allowed:
-            raise PaymentException(_(
-                "This payment is already being processed and can not be canceled any more."
-            ))
-
         payment.state = OrderPayment.PAYMENT_STATE_CANCELED
         payment.save(update_fields=['state'])
 

src/pretix/control/forms/event.py

@@ -231,7 +231,7 @@ class EventWizardBasicsForm(I18nModelForm):
             raise ValidationError({
                 'timezone': _('Your default locale must be specified.')
             })
-        if not data.get("no_taxes") and not data.get("tax_rate"):
+        if not data.get("no_taxes") and data.get("tax_rate") is None:
             raise ValidationError({
                 'tax_rate': _('You have not specified a tax rate. If you do not want us to compute sales taxes, please '
                               'check "{field}" above.').format(field=self.fields["no_taxes"].label)

src/pretix/control/views/main.py

@@ -313,7 +313,7 @@ class EventWizard(SafeSessionWizardView):
                     )
                 event.set_defaults()
 
-            if basics_data['tax_rate']:
+            if basics_data['tax_rate'] is not None:
                 if not event.settings.tax_rate_default or event.settings.tax_rate_default.rate != basics_data['tax_rate']:
                     event.settings.tax_rate_default = event.tax_rules.create(
                         name=LazyI18nString.from_gettext(gettext('VAT')),

src/tests/plugins/banktransfer/test_import.py

@@ -574,7 +574,7 @@ def test_pending_paypal_drop_fee(env, job):
         env[2].save()
         p = env[2].payments.create(
             provider='paypal',
-            state=OrderPayment.PAYMENT_STATE_CREATED,
+            state=OrderPayment.PAYMENT_STATE_PENDING,
             fee=fee,
             amount=env[2].total
         )