[4.1.x] Refs #22078 -- Added syndication test for feeds with static methods.

Backport of 7e4656e4b2 from main.

tests/syndication_tests/feeds.py

@@ -39,6 +39,12 @@ class TestRss2Feed(views.Feed):
     item_copyright = "Copyright (c) 2007, Sally Smith"
 
 
+class TestRss2FeedWithStaticMethod(TestRss2Feed):
+    @staticmethod
+    def categories():
+        return ("javascript", "vue")
+
+
 class TestRss2FeedWithGuidIsPermaLinkTrue(TestRss2Feed):
     def item_guid_is_permalink(self, item):
         return True

tests/syndication_tests/tests.py

@@ -196,6 +196,12 @@ class SyndicationFeedTest(FeedTestCase):
                 item.getElementsByTagName("guid")[0].attributes.get("isPermaLink")
             )
 
+    def test_rss2_feed_with_static_methods(self):
+        response = self.client.get("/syndication/rss2/with-static-methods/")
+        doc = minidom.parseString(response.content)
+        chan = doc.getElementsByTagName("rss")[0].getElementsByTagName("channel")[0]
+        self.assertCategories(chan, ["javascript", "vue"])
+
     def test_rss2_feed_guid_permalink_false(self):
         """
         Test if the 'isPermaLink' attribute of <guid> element of an item

tests/syndication_tests/urls.py

@@ -4,6 +4,7 @@ from . import feeds
 
 urlpatterns = [
     path("syndication/rss2/", feeds.TestRss2Feed()),
+    path("syndication/rss2/with-static-methods/", feeds.TestRss2FeedWithStaticMethod()),
     path("syndication/rss2/articles/<int:entry_id>/", feeds.TestGetObjectFeed()),
     path(
         "syndication/rss2/guid_ispermalink_true/",