Fix named route helper for routes nested inside deeply nested resources

[#6416 state:resolved]

actionpack/lib/action_dispatch/routing/mapper.rb

@@ -1442,7 +1442,7 @@ module ActionDispatch
 
             name = case @scope[:scope_level]
             when :nested
-              [member_name, prefix]
+              [name_prefix, prefix]
             when :collection
               [prefix, name_prefix, collection_name]
             when :new

actionpack/test/dispatch/routing_test.rb

@@ -187,7 +187,9 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
       end
 
       resources :posts, :only => [:index, :show] do
-        resources :comments, :except => :destroy
+        resources :comments, :except => :destroy do
+          get "views" => "comments#views", :as => :views
+        end
       end
 
       resource  :past, :only => :destroy
@@ -2308,6 +2310,12 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     end
   end
 
+  def test_nested_route_in_nested_resource
+    get "/posts/1/comments/2/views"
+    assert_equal "comments#views", @response.body
+    assert_equal "/posts/1/comments/2/views", post_comment_views_path(:post_id => '1', :comment_id => '2')
+  end
+
 private
   def with_test_routes
     yield