Extract QueueAdapter module for setting and looking up adapters

lib/active_job/base.rb

+require 'active_job/queue_adapter'
 require 'active_job/queue_adapters/inline_adapter'
 require 'active_support/core_ext/string/inflections'
 
 module ActiveJob
   class Base
-    cattr_accessor(:queue_adapter)   { ActiveJob::QueueAdapters::InlineAdapter }
+    extend QueueAdapter
+
     cattr_accessor(:queue_base_name) { "active_jobs" }
     cattr_accessor(:queue_name)      { queue_base_name }
 
@@ -15,11 +17,6 @@ def enqueue(*args)
       def queue_as(part_name)
         self.queue_name = "#{queue_base_name}_#{part_name}"
       end
-
-      def adapter=(adapter_name)
-        require "active_job/queue_adapters/#{adapter_name}_adapter"
-        ActiveJob::Base.queue_adapter = "ActiveJob::QueueAdapters::#{adapter_name.to_s.camelize}Adapter".constantize
-      end
     end
   end
 end
\ No newline at end of file

lib/active_job/queue_adapter.rb

+require 'active_job/queue_adapters/inline_adapter'
+require 'active_support/core_ext/string/inflections'
+
+module ActiveJob
+  module QueueAdapter
+    mattr_reader(:queue_adapter) { ActiveJob::QueueAdapters::InlineAdapter }
+
+    def queue_adapter=(name_or_adapter)
+      if name_or_adapter.is_a?(Symbol) || name_or_adapter.is_a?(String)
+        adapter = load_adapter(name_or_adapter)
+      else
+        adapter = name_or_adapter
+      end
+      
+      @@queue_adapter = adapter
+    end
+
+    private
+      def load_adapter(name)
+        require "active_job/queue_adapters/#{name}_adapter"
+        "ActiveJob::QueueAdapters::#{name.to_s.camelize}Adapter".constantize
+      end
+  end
+end
\ No newline at end of file

test/adapters/inline.rb

-ActiveJob::Base.adapter = :inline
\ No newline at end of file
+ActiveJob::Base.queue_adapter = :inline
\ No newline at end of file

test/adapters/resque.rb

-ActiveJob::Base.adapter = :resque
+ActiveJob::Base.queue_adapter = :resque
 Resque.inline = true

test/adapters/sidekiq.rb

 require 'sidekiq/testing/inline'
-ActiveJob::Base.adapter = :sidekiq
+ActiveJob::Base.queue_adapter = :sidekiq

test/adapters/sucker_punch.rb

 require 'sucker_punch/testing/inline'
-ActiveJob::Base.adapter = :sucker_punch
+ActiveJob::Base.queue_adapter = :sucker_punch

test/cases/adapter_test.rb

@@ -6,22 +6,22 @@ def setup
   end
 
   test 'should load inline adapter' do
-    ActiveJob::Base.adapter = :inline
+    ActiveJob::Base.queue_adapter = :inline
     assert_equal ActiveJob::QueueAdapters::InlineAdapter, ActiveJob::Base.queue_adapter
   end
 
   test 'should load resque adapter' do
-    ActiveJob::Base.adapter = :resque
+    ActiveJob::Base.queue_adapter = :resque
     assert_equal ActiveJob::QueueAdapters::ResqueAdapter, ActiveJob::Base.queue_adapter
   end
 
   test 'should load sidekiq adapter' do
-    ActiveJob::Base.adapter = :sidekiq
+    ActiveJob::Base.queue_adapter = :sidekiq
     assert_equal ActiveJob::QueueAdapters::SidekiqAdapter, ActiveJob::Base.queue_adapter
   end
 
   test 'should load sucker punch adapter' do
-    ActiveJob::Base.adapter = :sucker_punch
+    ActiveJob::Base.queue_adapter = :sucker_punch
     assert_equal ActiveJob::QueueAdapters::SuckerPunchAdapter, ActiveJob::Base.queue_adapter
   end