Bug fix: Evented notification subscribers can handle published events

activesupport/lib/active_support/notifications/fanout.rb

@@ -79,6 +79,13 @@ module ActiveSupport
           def initialize(pattern, delegate)
             @pattern = pattern
             @delegate = delegate
+            @can_publish = delegate.respond_to?(:publish)
+          end
+
+          def publish(name, *args)
+            if @can_publish
+              @delegate.publish name, *args
+            end
           end
 
           def start(name, id, payload)

activesupport/test/notifications_test.rb

@@ -81,6 +81,20 @@ module Notifications
     end
   end
 
+  class TestSubscriber
+    attr_reader :starts, :finishes, :publishes
+
+    def initialize
+      @starts    = []
+      @finishes  = []
+      @publishes = []
+    end
+
+    def start(*args);  @starts << args; end
+    def finish(*args); @finishes << args; end
+    def publish(*args); @publishes << args; end
+  end
+
   class SyncPubSubTest < TestCase
     def test_events_are_published_to_a_listener
       @notifier.publish :foo
@@ -144,6 +158,14 @@ module Notifications
       assert_equal [[:foo]], @another
     end
 
+    def test_publish_with_subscriber
+      subscriber = TestSubscriber.new
+      @notifier.subscribe nil, subscriber
+      @notifier.publish :foo
+
+      assert_equal [[:foo]], subscriber.publishes
+    end
+
     private
       def event(*args)
         args