add get templatetag (#17284)

combo/public/templatetags/combo.py

@@ -157,3 +157,10 @@ def has_role(user, groupname):
     if not user or user.is_anonymous():
         return False
     return user.groups.filter(name=groupname).exists()
+
+@register.filter(name='get')
+def get(obj, key):
+    try:
+        return obj.get(key)
+    except AttributeError:
+        return None

tests/test_public_templatetags.py

@@ -58,3 +58,20 @@ def test_has_role():
     assert t.render(context) == 'False'
     request.user = AnonymousUser()
     assert t.render(context) == 'False'
+
+def test_get():
+    t = Template('{% load combo %}{{ foo|get:"foo-bar" }}')
+    context = Context({'foo': {'foo-bar': 'hello'}})
+    assert t.render(context) == 'hello'
+    context = Context({'foo': {'bar-foo': 'hello'}})
+    assert t.render(context) == 'None'
+    context = Context({'foo': None})
+    assert t.render(context) == 'None'
+
+    t = Template('{% load combo %}{{ foo|get:"foo-bar"|default:"" }}')
+    context = Context({'foo': {'rab': 'hello'}})
+    assert t.render(context) == ''
+
+    t = Template('{% load combo %}{{ foo|get:key }}')
+    context = Context({'foo': {'foo-bar': 'hello'}, 'key': 'foo-bar'})
+    assert t.render(context) == 'hello'