Add test for money filter + streamline rounding error protection logic (#3714)

* add test cases

* use rounding protection only for currencies with <2 decimal places

* add more test cases

* use parameterized tests

src/tests/base/test_templatetag.py

@@ -19,34 +19,91 @@
 # You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
 # <https://www.gnu.org/licenses/>.
 #
+from decimal import Decimal
+
+import pytest
 from django.template import Context, Template
 from django.test import RequestFactory
+from django.utils import translation
 
-TEMPLATE_REPLACE_PAGE = Template("{% load urlreplace %}{% url_replace request 'page' 3 %}")
+from pretix.base.templatetags.money import money_filter
+
+TEMPLATE_REPLACE_PAGE = Template(
+    "{% load urlreplace %}{% url_replace request 'page' 3 %}"
+)
+TEMPLATE_MONEY_FILTER = Template("{% load money %}{{ my_amount|money:my_currency }}")
+NBSP = "\xa0"
 
 
 def test_urlreplace_add__first_parameter():
     factory = RequestFactory()
-    request = factory.get('/customer/details')
-    rendered = TEMPLATE_REPLACE_PAGE.render(Context({
-        'request': request
-    })).strip()
-    assert rendered == 'page=3'
+    request = factory.get("/customer/details")
+    rendered = TEMPLATE_REPLACE_PAGE.render(Context({"request": request})).strip()
+    assert rendered == "page=3"
 
 
 def test_urlreplace_add_parameter():
     factory = RequestFactory()
-    request = factory.get('/customer/details?foo=bar')
-    rendered = TEMPLATE_REPLACE_PAGE.render(Context({
-        'request': request
-    })).strip()
-    assert rendered in ('foo=bar&amp;page=3', 'page=3&amp;foo=bar')
+    request = factory.get("/customer/details?foo=bar")
+    rendered = TEMPLATE_REPLACE_PAGE.render(Context({"request": request})).strip()
+    assert rendered in ("foo=bar&amp;page=3", "page=3&amp;foo=bar")
 
 
 def test_urlreplace_replace_parameter():
     factory = RequestFactory()
-    request = factory.get('/customer/details?page=15')
-    rendered = TEMPLATE_REPLACE_PAGE.render(Context({
-        'request': request
-    })).strip()
-    assert rendered == 'page=3'
+    request = factory.get("/customer/details?page=15")
+    rendered = TEMPLATE_REPLACE_PAGE.render(Context({"request": request})).strip()
+    assert rendered == "page=3"
+
+
+@pytest.mark.parametrize(
+    "locale,amount,currency,expected",
+    [
+        ("en", None, "USD", "$0.00"),
+        ("en", 1000000, "USD", "$1,000,000.00"),
+        ("en", Decimal("1000.00"), "USD", "$1,000.00"),
+        ("de", Decimal("1.23"), "EUR", "1,23" + NBSP + "€"),
+        ("de", Decimal("1000.00"), "EUR", "1.000,00" + NBSP + "€"),
+        ("de", Decimal("1023"), "JPY", "1.023" + NBSP + "¥"),
+
+        ("en", Decimal("1023"), "JPY", "¥1,023"),
+
+        ("pt-pt", Decimal("10.00"), "EUR", "10,00" + NBSP + "€"),
+        ("pt-br", Decimal("10.00"), "EUR", "€" + NBSP + "10,00"),
+
+        # unknown currency
+        ("de", Decimal("1234.56"), "FOO", "1.234,56" + NBSP + "FOO"),
+        ("de", Decimal("1234.567"), "FOO", "1.234,57" + NBSP + "FOO"),
+
+        # rounding errors
+        ("de", Decimal("1.234"), "EUR", "1,23" + NBSP + "€"),
+        ("de", Decimal("1023.1"), "JPY", "JPY 1023,10"),
+    ]
+)
+def test_money_filter(locale, amount, currency, expected):
+    factory = RequestFactory()
+    translation.activate(locale)
+    request = factory.get("/foo/bar")
+    rendered = TEMPLATE_MONEY_FILTER.render(
+        Context(
+            {
+                "request": request,
+                "my_amount": amount,
+                "my_currency": currency,
+            }
+        )
+    ).strip()
+    assert rendered == expected
+
+
+@pytest.mark.parametrize(
+    "locale,amount,currency,expected",
+    [
+        ("de", Decimal("1000.00"), "EUR", "1000,00"),
+        ("en", Decimal("1000.00"), "EUR", "1000.00"),
+        ("de", Decimal("1023.1"), "JPY", "1023,10"),
+    ]
+)
+def test_money_filter_hidecurrency(locale, amount, currency, expected):
+    translation.activate(locale)
+    assert money_filter(amount, currency, hide_currency=True) == expected