Code review feedback

lib/view_component/engine.rb

@@ -88,9 +88,9 @@ module ViewComponent
       options = app.config.view_component
 
       if options.show_previews
-        preview_controller = options.preview_controller.sub(/Controller$/, "").underscore
-
         app.routes.append do
+          preview_controller = options.preview_controller.sub(/Controller$/, "").underscore
+
           get options.preview_route, to: "#{preview_controller}#index", as: :preview_view_components, internal: true
           get "#{options.preview_route}/*path", to: "#{preview_controller}#previews", as: :preview_view_component, internal: true
         end

test/app/controllers/my_preview_controller.rb

@@ -1,12 +1,7 @@
 # frozen_string_literal: true
 
 class MyPreviewController < ViewComponentsController
-
   def index
-    if params[:custom_controller].present?
-      render plain: "Custom controller"
-    else
-      super
-    end
+    render plain: "Custom controller"
   end
 end

test/config/environments/test.rb

@@ -28,7 +28,7 @@ Dummy::Application.configure do
   config.view_component.preview_paths << "#{Rails.root}/lib/component_previews"
   config.view_component.render_monkey_patch_enabled = true
   config.view_component.test_controller = "IntegrationExamplesController"
-  config.view_component.preview_controller = "MyPreviewController"
+  # config.view_component.preview_controller = "MyPreviewController"
 
   # Tell Action Mailer not to deliver emails to the real world.
   # The :test delivery method accumulates sent emails in the

test/test_helper.rb

@@ -30,6 +30,15 @@ def with_preview_route(new_value)
   app.reloader.reload!
 end
 
+def with_preview_controller(new_value)
+  old_value = Rails.application.config.view_component.preview_controller
+  Rails.application.config.view_component.preview_controller = new_value
+  app.reloader.reload!
+  yield
+  Rails.application.config.view_component.preview_controller = old_value
+  app.reloader.reload!
+end
+
 def modify_file(file, content)
   filename = Rails.root.join(file)
   old_content = File.read(filename)

test/view_component/integration_test.rb

@@ -344,8 +344,10 @@ class IntegrationTest < ActionDispatch::IntegrationTest
   end
 
   def test_renders_the_previews_in_the_configured_controller
-    get "/rails/view_components/?custom_controller=true"
-    assert_equal response.body, "Custom controller"
+    with_preview_controller("MyPreviewController") do
+      get "/rails/view_components"
+      assert_equal response.body, "Custom controller"
+    end
   end
 
   def test_renders_singular_and_collection_slots_with_arguments