fix(Railtie) add asset paths another way, add test for precompiling assets

Author: rmosolgo

lib/react/rails/railtie.rb

@@ -36,8 +36,8 @@ class Railtie < ::Rails::Railtie
         directory = app.config.react.variant == :production ? 'production' : 'development'
         directory += '-with-addons' if app.config.react.addons
 
-        app.assets.append_path(root_path.join('lib/assets/react-source/').join(directory).to_s)
-        app.assets.append_path(root_path.join('lib/assets/javascripts/').to_s)
+        app.config.assets.paths << root_path.join('lib/assets/react-source/').join(directory).to_s
+        app.config.assets.paths << root_path.join('lib/assets/javascripts/').to_s
       end
 
       config.after_initialize do |app|

test/react_test.rb

@@ -16,4 +16,10 @@ class ReactTest < ActionDispatch::IntegrationTest
     assert_response :success
     assert_equal react_file_token, @response.body
   end
+
+  test 'precompiling assets works' do
+    Dummy::Application.load_tasks
+    Rake::Task['assets:precompile'].invoke
+    FileUtils.rm_r(File.expand_path("../dummy/public/assets", __FILE__))
+  end
 end