Allow Resque (queue target) to be overridden for testing

lib/resque_mailer.rb

@@ -1,7 +1,7 @@
 module Resque
   module Mailer
     class << self
-      attr_accessor :default_queue_name
+      attr_accessor :default_queue_name, :default_queue_target
       attr_reader :excluded_environments
 
       def excluded_environments=(envs)
@@ -13,6 +13,7 @@ def included(base)
       end
     end
 
+    self.default_queue_target = ::Resque
     self.default_queue_name = "mailer"
     self.excluded_environments = [:test]
 
@@ -25,11 +26,12 @@ def method_missing(method_name, *args)
         return super if environment_excluded?
 
         if action_methods.include?(method_name.to_s)
+          resque = self.resque
           mailer_class = self
           super.tap do |resque_mail|
             resque_mail.class_eval do
               define_method(:deliver) do
-                ::Resque.enqueue(mailer_class, method_name, *args)
+                resque.enqueue(mailer_class, method_name, *args)
                 self
               end
             end
@@ -51,6 +53,10 @@ def queue
         ::Resque::Mailer.default_queue_name
       end
 
+      def resque
+        ::Resque::Mailer.default_queue_target
+      end
+
       def excluded_environment?(name)
         ::Resque::Mailer.excluded_environments && ::Resque::Mailer.excluded_environments.include?(name.to_sym)
       end

spec/resque_mailer_spec.rb

@@ -1,5 +1,9 @@
 require File.join(File.expand_path(File.dirname(__FILE__)), 'spec_helper')
 
+class FakeResque
+  def self.enqueue(*args); end
+end
+
 class Rails3Mailer < ActionMailer::Base
   include Resque::Mailer
   default :from => "from@example.org", :subject => "Subject"
@@ -11,22 +15,28 @@ def test_mail(*params)
 end
 
 describe Resque::Mailer do
+  let(:resque) { FakeResque }
+
   before do
+    Resque::Mailer.default_queue_target = resque
     Rails3Mailer.stub(:current_env => :test)
   end
 
+  describe "resque" do
+    it "allows overriding of the default queue target (for testing)" do
+      Resque::Mailer.default_queue_target = FakeResque
+      Rails3Mailer.resque.should == FakeResque
+    end
+  end
+
   describe "queue" do
-    context "when using the default" do
-      it "should return 'mailer'" do
-        Rails3Mailer.queue.should == "mailer"
-      end
+    it "defaults to the 'mailer' queue" do
+      Rails3Mailer.queue.should == "mailer"
     end
 
-    context "when modified by user" do
-      it "should return proper queue name" do
-        Resque::Mailer.default_queue_name = "postal"
-        Rails3Mailer.queue.should == "postal"
-      end
+    it "allows overriding of the default queue name" do
+      Resque::Mailer.default_queue_name = "postal"
+      Rails3Mailer.queue.should == "postal"
     end
   end
 
@@ -37,24 +47,20 @@ def test_mail(*params)
       }
     end
 
-    before(:each) do
-      Resque.stub(:enqueue)
-    end
-
     it 'should not deliver the email synchronously' do
       lambda { @delivery.call }.should_not change(ActionMailer::Base.deliveries, :size)
     end
 
     it 'should place the deliver action on the Resque "mailer" queue' do
-      Resque.should_receive(:enqueue).with(Rails3Mailer, :test_mail, Rails3Mailer::MAIL_PARAMS)
+      resque.should_receive(:enqueue).with(Rails3Mailer, :test_mail, Rails3Mailer::MAIL_PARAMS)
       @delivery.call
     end
 
     context "when current env is excluded" do
       it 'should not deliver through Resque for excluded environments' do
         Resque::Mailer.stub(:excluded_environments => [:custom])
         Rails3Mailer.should_receive(:current_env).and_return(:custom)
-        Resque.should_not_receive(:enqueue)
+        resque.should_not_receive(:enqueue)
         @delivery.call
       end
     end