Always use original url_for when generating direct routes

Action View overrides `url_for` in the view context to render paths by
default when using `url_for` and this means that direct route helpers
don't get the full url when called with the url suffix. To fix this
always call the original `url_for`.

actionpack/lib/action_dispatch/routing/route_set.rb

@@ -509,6 +509,10 @@ def url_for(options)
               @_proxy.url_for(options)
             end
 
+            def full_url_for(options)
+              @_proxy.full_url_for(options)
+            end
+
             def route_for(name, *args)
               @_proxy.route_for(name, *args)
             end
@@ -619,7 +623,7 @@ def initialize(name, defaults, &block)
 
         def call(t, args, only_path = false)
           options = args.extract_options!
-          url = t.url_for(eval_block(t, args, options))
+          url = t.full_url_for(eval_block(t, args, options))
 
           if only_path
             "/" + url.partition(%r{(?<!/)/(?!/)}).last

actionpack/lib/action_dispatch/routing/url_for.rb

@@ -164,6 +164,10 @@ def url_options
       # implicitly used by +url_for+ can always be overwritten like shown on the
       # last +url_for+ calls.
       def url_for(options = nil)
+        full_url_for(options)
+      end
+
+      def full_url_for(options = nil) # :nodoc:
         case options
         when nil
           _routes.url_for(url_options.symbolize_keys)

actionview/test/activerecord/polymorphic_routes_test.rb

@@ -730,3 +730,49 @@ def assert_url(url, args)
     assert_equal url.sub(/http:\/\/#{host}/, ""), url_for(args)
   end
 end
+
+class DirectRoutesTest < ActionView::TestCase
+  class Linkable
+    attr_reader :id
+
+    def self.name
+      super.demodulize
+    end
+
+    def initialize(id)
+      @id = id
+    end
+
+    def linkable_type
+      self.class.name.underscore
+    end
+  end
+
+  class Category < Linkable; end
+  class Collection < Linkable; end
+  class Product < Linkable; end
+
+  Routes = ActionDispatch::Routing::RouteSet.new
+  Routes.draw do
+    resources :categories, :collections, :products
+    direct(:linkable) { |linkable| [:"#{linkable.linkable_type}", { id: linkable.id }] }
+  end
+
+  include Routes.url_helpers
+
+  def setup
+    @category = Category.new("1")
+    @collection = Collection.new("2")
+    @product = Product.new("3")
+  end
+
+  def test_direct_routes
+    assert_equal "/categories/1", linkable_path(@category)
+    assert_equal "/collections/2", linkable_path(@collection)
+    assert_equal "/products/3", linkable_path(@product)
+
+    assert_equal "http://test.host/categories/1", linkable_url(@category)
+    assert_equal "http://test.host/collections/2", linkable_url(@collection)
+    assert_equal "http://test.host/products/3", linkable_url(@product)
+  end
+end