Use synchronous queue by default. Separate queued message delivery jo…

…bs from the queued message wrappers so the queue itself needn't be marshaled (due to queue reference QueuedMessage).

actionmailer/lib/action_mailer/base.rb

@@ -4,6 +4,7 @@
 require 'active_support/core_ext/string/inflections'
 require 'active_support/core_ext/hash/except'
 require 'active_support/core_ext/module/anonymous'
+require 'active_support/queueing'
 require 'action_mailer/log_subscriber'
 
 module ActionMailer #:nodoc:
@@ -393,6 +394,7 @@ class Base < AbstractController::Base
     }.freeze
 
     class_attribute :queue
+    self.queue = ActiveSupport::SynchronousQueue.new
 
     class << self
       # Register one or more Observers which will be notified when mail is delivered.

actionmailer/lib/action_mailer/queued_message.rb

@@ -5,23 +5,33 @@ class QueuedMessage < ::Delegator
     attr_reader :queue
 
     def initialize(queue, mailer_class, method_name, *args)
-      @queue        = queue
-      @mailer_class = mailer_class
-      @method_name  = method_name
-      @args         = args
+      @queue = queue
+      @job   = DeliveryJob.new(mailer_class, method_name, args)
     end
 
     def __getobj__
-      @actual_message ||= @mailer_class.send(:new, @method_name, *@args).message
+      @job.message
     end
 
-    def run
-      __getobj__.deliver
+    # Queues the message for delivery.
+    def deliver
+      tap { @queue.push @job }
     end
 
-    # Will push the message onto the Queue to be processed
-    def deliver
-      @queue << self
+    class DeliveryJob
+      def initialize(mailer_class, method_name, args)
+        @mailer_class = mailer_class
+        @method_name  = method_name
+        @args         = args
+      end
+
+      def message
+        @message ||= @mailer_class.send(:new, @method_name, *@args).message
+      end
+
+      def run
+        message.deliver
+      end
     end
   end
 end

actionmailer/test/abstract_unit.rb

@@ -27,7 +27,6 @@
 
 FIXTURE_LOAD_PATH = File.expand_path('fixtures', File.dirname(__FILE__))
 ActionMailer::Base.view_paths = FIXTURE_LOAD_PATH
-ActionMailer::Base.queue = ActiveSupport::SynchronousQueue.new
 
 class MockSMTP
   def self.deliveries

actionmailer/test/base_test.rb

@@ -412,7 +412,7 @@ def teardown
     BaseMailer.deliveries.clear
     BaseMailer.expects(:deliver_mail).once
     mail = BaseMailer.welcome.deliver
-    assert_instance_of Mail::Message, mail
+    assert_equal 'The first email on new API!', mail.subject
   end
 
   test "calling deliver on the action should increment the deliveries collection if using the test mailer" do
@@ -422,24 +422,15 @@ def teardown
     assert_equal(1, BaseMailer.deliveries.length)
   end
 
-  def stub_queue(klass, queue)
-    Class.new(klass) {
-      extend Module.new {
-        define_method :queue do
-          queue
-        end
-      }
-    }
-  end
-
   test "delivering message asynchronously" do
-    testing_queue = ActiveSupport::TestQueue.new
     AsyncMailer.delivery_method = :test
     AsyncMailer.deliveries.clear
-    stub_queue(AsyncMailer, testing_queue).welcome.deliver
-    assert_equal(0, AsyncMailer.deliveries.length)
-    testing_queue.drain
-    assert_equal(1, AsyncMailer.deliveries.length)
+
+    AsyncMailer.welcome.deliver
+    assert_equal 0, AsyncMailer.deliveries.length
+
+    AsyncMailer.queue.drain
+    assert_equal 1, AsyncMailer.deliveries.length
   end
 
   test "calling deliver, ActionMailer should yield back to mail to let it call :do_delivery on itself" do

actionmailer/test/mailers/async_mailer.rb

@@ -1,2 +1,3 @@
 class AsyncMailer < BaseMailer
+  self.queue = ActiveSupport::TestQueue.new
 end