add group templatetag (for regroup objects) (#17285)

combo/public/templatetags/combo.py

@@ -164,3 +164,11 @@ def get(obj, key):
         return obj.get(key)
     except AttributeError:
         return None
+
+@register.filter(name='get_group')
+def get_group(group_list, group_name):
+    ret = []
+    for group in group_list:
+        if group['grouper'] == group_name:
+            ret.extend(group['list'])
+    return ret

tests/test_public_templatetags.py

@@ -75,3 +75,15 @@ def test_get():
     t = Template('{% load combo %}{{ foo|get:key }}')
     context = Context({'foo': {'foo-bar': 'hello'}, 'key': 'foo-bar'})
     assert t.render(context) == 'hello'
+
+def test_get_group():
+    context = Context({'cities': [
+        {'name': 'Mumbai', 'population': '19,000,000', 'country': 'India'},
+        {'name': 'New York', 'population': '20,000,000', 'country': 'USA'},
+        {'name': 'Calcutta', 'population': '15,000,000', 'country': 'India'},
+        {'name': 'Chicago', 'population': '7,000,000', 'country': 'USA'},
+        {'name': 'Tokyo', 'population': '33,000,000', 'country': 'Japan'},
+    ]})
+    t = Template('{% load combo %}{% regroup cities by country as country_list %}'
+                 '{% for c in country_list|get_group:"USA" %}{{c.name}},{% endfor %}')
+    assert t.render(context) == 'New York,Chicago,'