# HG changeset patch
# User Brian Neal <bgneal@gmail.com>
# Date 1739413130 21600
# Node ID e2409dab30c3db696ed21c632a132637d5897d0d
# Parent  42fef17a89a4bc718a96c2ebcb054750f8a53ed7
Add unit test for banners templatetags.

diff -r 42fef17a89a4 -r e2409dab30c3 banners/templatetags/banner_tags.py
--- a/banners/templatetags/banner_tags.py	Wed Feb 12 19:03:43 2025 -0600
+++ b/banners/templatetags/banner_tags.py	Wed Feb 12 20:18:50 2025 -0600
@@ -25,7 +25,7 @@
     For each campaign, a list of banner URLs are kept in Redis. Each time this
     tag is called, the front banner is popped off the list. When the list is
     empty, we refresh the list from the database. In this way the banners for a
-    campaign are cycled through. 
+    campaign are cycled through.
     """
     key = BANNER_URL_KEY % slug
 
diff -r 42fef17a89a4 -r e2409dab30c3 banners/tests/test_templatetags.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/banners/tests/test_templatetags.py	Wed Feb 12 20:18:50 2025 -0600
@@ -0,0 +1,49 @@
+"""
+Tests for the banners application's template tags.
+
+"""
+from django.test import TestCase
+
+from mock import call, patch, Mock
+
+
+class BannersTemplateTagsTestCase(TestCase):
+    def setUp(self):
+        self.url = 'http://example.com/some/campaign'
+        self.slug = 'slug'
+
+    @patch('banners.templatetags.banner_tags.get_redis_connection')
+    def test_banner_url_cache_hit(self, connection_mock):
+        redis_mock = Mock()
+        connection_mock.return_value = redis_mock
+        redis_mock.lpop.return_value = self.url
+
+        self.assertEqual(banner_url(self.slug), self.url)
+
+        self.assertEqual(redis_mock.mock_calls, [
+            call.lpop('banners:url:{}'.format(self.slug)),
+        ])
+
+    @patch('banners.templatetags.banner_tags.Banner')
+    @patch('banners.templatetags.banner_tags.get_redis_connection')
+    def test_banner_url_cache_miss(self, connection_mock, banner_mock):
+        redis_mock = Mock()
+        connection_mock.return_value = redis_mock
+        redis_mock.lpop.return_value = None
+
+        qs = [Mock(), Mock()]
+        qs[0].image.configure_mock(url='url0')
+        qs[1].image.configure_mock(url='url1')
+
+        banner_mock.objects.filter.return_value = qs
+
+        self.assertEqual(banner_url(self.slug), 'url0')
+
+        redis_key = 'banners:url:{}'.format(self.slug)
+        self.assertEqual(redis_mock.mock_calls, [
+            call.lpop(redis_key),
+            call.rpush(redis_key, 'url1'),
+        ])
+        self.assertEqual(banner_mock.objects.filter.mock_calls, [
+            call(campaign__slug=self.slug),
+        ])