JqueryRjs.use_alias_method_chain?

Cache alias_method_chain conditional to a single spot

lib/jquery-rjs.rb

@@ -6,6 +6,11 @@
 end
 
 module JqueryRjs
+  def use_alias_method_chain?
+    @use_alias_method_chain ||= RUBY_VERSION < '2'
+  end
+  module_function :use_alias_method_chain?
+
   class Engine < Rails::Engine
     initializer 'jquery-rjs.initialize' do
       ActiveSupport.on_load(:action_controller) do

lib/jquery-rjs/rendering.rb

@@ -1,19 +1,19 @@
 require 'action_view/helpers/rendering_helper'
 
 module JqueryRjs::RenderingHelper
-  method_name = "render#{'_with_update' if RUBY_VERSION < '2'}"
+  method_name = "render#{'_with_update' if JqueryRjs.use_alias_method_chain?}"
   define_method(method_name) do |options = {}, locals = {}, &block|
     if options == :update
       update_page(&block)
     else
       args = options, locals, block
-      RUBY_VERSION < '2' ? render_without_update(*args) : super(*args)
+      JqueryRjs.use_alias_method_chain? ? render_without_update(*args) : super(*args)
     end
   end
 end
 
 
-if RUBY_VERSION < '2'
+if JqueryRjs.use_alias_method_chain?
   ActionView::Helpers::RenderingHelper.module_eval do
     include JqueryRjs::RenderingHelper
     alias_method_chain :render, :update

lib/jquery-rjs/selector_assertions.rb

@@ -197,7 +197,7 @@ def response_from_page
 
   # +assert_select+ and +css_select+ call this to obtain the content in the HTML
   # page, or from all the RJS statements, depending on the type of response.
-  define_method("response_from_page#{'_with_rjs' if RUBY_VERSION < '2'}") do
+  define_method("response_from_page#{'_with_rjs' if JqueryRjs.use_alias_method_chain?}") do
     content_type = @response.content_type
 
     if content_type && Mime[:js] =~ content_type
@@ -216,7 +216,7 @@ def response_from_page
 
       root
     else
-      RUBY_VERSION < '2' ? response_from_page_without_rjs : super()
+      JqueryRjs.use_alias_method_chain? ? response_from_page_without_rjs : super()
     end
   end
 
@@ -240,7 +240,7 @@ def unescape_rjs(rjs_string)
                     Rails::Dom::Testing::Assertions::SelectorAssertions
                   end
 
-if RUBY_VERSION < '2'
+if JqueryRjs.use_alias_method_chain?
   module_to_patch.module_eval do
     include JqueryRjs::SelectorAssertions
     alias_method_chain :response_from_page, :rjs