1 files changed, 23 insertions, 0 deletions
diff --git a/activesupport/test/subscriber_test.rb b/activesupport/test/subscriber_test.rb
index 6b012e43af..bc8d8f1c13 100644
--- a/activesupport/test/subscriber_test.rb
+++ b/activesupport/test/subscriber_test.rb
@@ -23,6 +23,21 @@ class TestSubscriber < ActiveSupport::Subscriber
     end
 end
 
+class TestSubscriber2 < ActiveSupport::Subscriber
+  attach_to :doodle
+  detach_from :doodle
+
+  cattr_reader :events
+
+  def self.clear
+    @@events = []
+  end
+
+  def open_party(event)
+    events << event
+  end
+end
+
 # Monkey patch subscriber to test that only one subscriber per method is added.
 class TestSubscriber
   remove_method :open_party
@@ -34,6 +49,7 @@ end
 class SubscriberTest < ActiveSupport::TestCase
   def setup
     TestSubscriber.clear
+    TestSubscriber2.clear
   end
 
   def test_attaches_subscribers
@@ -53,4 +69,11 @@ class SubscriberTest < ActiveSupport::TestCase
 
     assert_equal [], TestSubscriber.events
   end
+
+  def test_detaches_subscribers
+    ActiveSupport::Notifications.instrument("open_party.doodle")
+
+    assert_equal [], TestSubscriber2.events
+    assert_equal 1, TestSubscriber.events.size
+  end
 end