misc: add |check_no_duplicates filter tag (#86530)

tests/test_templates.py

@@ -1649,3 +1649,16 @@ def test_with_auth(pub):
         Template('{{ service_url|with_auth:"username:password" }}').render(context)
         == 'https://username:password@www.example.net/api/whatever?x=y'
     )
+
+
+def test_check_no_duplicates(pub):
+    pub.loggederror_class.wipe()
+    context = {'value1': ['a', 'b', 'c'], 'value2': ['a', 'a', 'b', 'c'], 'value3': None, 'value4': '12'}
+    assert Template('{% if value1|check_no_duplicates %}ok{% else %}nok{% endif %}').render(context) == 'ok'
+    assert Template('{% if value2|check_no_duplicates %}ok{% else %}nok{% endif %}').render(context) == 'nok'
+    assert Template('{% if value3|check_no_duplicates %}ok{% else %}nok{% endif %}').render(context) == 'ok'
+    assert pub.loggederror_class.count() == 0
+    assert Template('{% if value4|check_no_duplicates %}ok{% else %}nok{% endif %}').render(context) == 'nok'
+    assert pub.loggederror_class.count() == 1
+    logged_error = pub.loggederror_class.select()[0]
+    assert logged_error.summary == '|check_no_duplicates not used on a list (12)'

wcs/qommon/templatetags/qommon.py

@@ -1289,3 +1289,12 @@ def with_auth(value, arg):
 @register.filter
 def wbr(value):
     return mark_safe(value.replace('_', '_<wbr/>'))
+
+
+@register.filter
+def check_no_duplicates(value):
+    value = unlazy(value)
+    if not isinstance(value, (type(None), tuple, list, set)):
+        get_publisher().record_error(_('|check_no_duplicates not used on a list (%s)') % value)
+        return False
+    return bool(len(value or []) == len(set(value or [])))