Add support for custom taxation rules

src/tests/base/test_taxrules.py

@@ -0,0 +1,387 @@
+import json
+from decimal import Decimal
+
+import pytest
+from django.utils.timezone import now
+from django_countries.fields import Country
+
+from pretix.base.models import Event, InvoiceAddress, Organizer, TaxRule
+
+
+@pytest.fixture
+def event():
+    o = Organizer.objects.create(name='Dummy', slug='dummy')
+    event = Event.objects.create(
+        organizer=o, name='Dummy', slug='dummy',
+        date_from=now()
+    )
+    return event
+
+
+@pytest.mark.django_db
+def test_from_gross_price(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=True
+    )
+    tp = tr.tax(Decimal('100.00'))
+    assert tp.gross == Decimal('100')
+    assert tp.net == Decimal('90.91')
+    assert tp.tax == Decimal('100.00') - Decimal('90.91')
+    assert tp.rate == Decimal('10.00')
+
+
+@pytest.mark.django_db
+def test_from_net_price(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    tp = tr.tax(Decimal('100.00'))
+    assert tp.gross == Decimal('110.00')
+    assert tp.net == Decimal('100.00')
+    assert tp.tax == Decimal('10.00')
+    assert tp.rate == Decimal('10.00')
+
+
+@pytest.mark.django_db
+def test_reverse_charge_no_address(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True,
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    assert not tr.is_reverse_charge(None)
+    assert tr.tax_applicable(None)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_no_country(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True,
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_individual_same_country(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=False,
+        country=Country('DE')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_individual_eu(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=False,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_individual_3rdc(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=False,
+        country=Country('US')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_business_same_country(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('DE')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_business_eu(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_business_3rdc(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('US')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_valid_vat_id_business_same_country(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('DE'),
+        vat_id='DE123456',
+        vat_id_validated=True
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_valid_vat_id_business_eu(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        vat_id='AT12346',
+        vat_id_validated=True,
+        country=Country('AT')
+    )
+    assert tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_valid_vat_id_business_3rdc(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('US'),
+        vat_id='US12346',
+        vat_id_validated=True
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_reverse_charge_disabled(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=False, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        vat_id='AT12346',
+        vat_id_validated=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_override(event):
+    tr = TaxRule(
+        event=event, eu_reverse_charge=True, home_country=Country('DE'),
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'ZZ', 'address_type': '', 'action': 'vat'}
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        vat_id='AT12346',
+        vat_id_validated=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_in_order(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'ZZ', 'address_type': '', 'action': 'vat'},
+            {'country': 'ZZ', 'address_type': '', 'action': 'reverse'}
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        vat_id='AT12346',
+        vat_id_validated=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_any_country(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'ZZ', 'address_type': '', 'action': 'no'},
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_eu_country(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'EU', 'address_type': '', 'action': 'no'},
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('US')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_specific_country(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'AT', 'address_type': '', 'action': 'no'},
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('DE')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_individual(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'ZZ', 'address_type': 'individual', 'action': 'no'},
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=False,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('DE')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_business(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'ZZ', 'address_type': 'business', 'action': 'no'},
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)
+    ia = InvoiceAddress(
+        is_business=False,
+        country=Country('DE')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+
+
+@pytest.mark.django_db
+def test_custom_rules_vat_id(event):
+    tr = TaxRule(
+        event=event,
+        rate=Decimal('10.00'), price_includes_tax=False,
+        custom_rules=json.dumps([
+            {'country': 'EU', 'address_type': 'business_vat_id', 'action': 'reverse'},
+        ])
+    )
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('AT')
+    )
+    assert not tr.is_reverse_charge(ia)
+    assert tr.tax_applicable(ia)
+    ia = InvoiceAddress(
+        is_business=True,
+        country=Country('DE'),
+        vat_id='DE1234',
+        vat_id_validated=True
+    )
+    assert tr.is_reverse_charge(ia)
+    assert not tr.tax_applicable(ia)