Ensure asset_path defaults to nil for application

railties/lib/rails/application.rb

@@ -138,6 +138,10 @@ def config
 
   protected
 
+    def default_asset_path
+      nil
+    end
+
     def default_middleware_stack
       ActionDispatch::MiddlewareStack.new.tap do |middleware|
         rack_cache = config.action_controller.perform_caching && config.action_dispatch.rack_cache

railties/lib/rails/engine.rb

@@ -499,7 +499,7 @@ def load_seed
     end
 
     initializer :append_asset_paths do
-      config.asset_path ||= "/#{railtie_name}%s"
+      config.asset_path ||= default_asset_path
 
       public_path = paths["public"].first
       if config.compiled_asset_path && File.exist?(public_path)
@@ -553,6 +553,11 @@ def load_seed
     end
 
   protected
+
+    def default_asset_path
+      "/#{railtie_name}%s"
+    end
+
     def routes?
       defined?(@routes)
     end

railties/test/application/configuration_test.rb

@@ -95,6 +95,11 @@ def teardown
       assert AppTemplate::Application.config.allow_concurrency
     end
 
+    test "asset_path defaults to nil for application" do
+      require "#{app_path}/config/environment"
+      assert_equal nil, AppTemplate::Application.config.asset_path
+    end
+
     test "the application can be marked as threadsafe when there are no frameworks" do
       FileUtils.rm_rf("#{app_path}/config/environments")
       add_to_config <<-RUBY