UX: Redirect /faq, /rules, /conduct to /guidelines (#27592)

app/controllers/static_controller.rb

@@ -36,6 +36,14 @@ class StaticController < ApplicationController
       return redirect_to path("/login")
     end
 
+    rename_faq = SiteSetting.experimental_rename_faq_to_guidelines
+
+    if rename_faq
+      redirect_paths = %w[/rules /conduct]
+      redirect_paths << "/faq" if SiteSetting.faq_url.blank?
+      return redirect_to(path("/guidelines")) if redirect_paths.include?(request.path)
+    end
+
     map = DEFAULT_PAGES.deep_merge(CUSTOM_PAGES)
     @page = params[:id]
 
@@ -58,16 +66,23 @@ class StaticController < ApplicationController
       @topic = Topic.find_by_id(SiteSetting.get(topic_id))
       raise Discourse::NotFound unless @topic
 
+      page_name =
+        if @page == "faq"
+          rename_faq ? "guidelines" : "faq"
+        else
+          @page
+        end
+
       title_prefix =
-        if I18n.exists?("js.#{@page}")
-          I18n.t("js.#{@page}")
+        if I18n.exists?("js.#{page_name}")
+          I18n.t("js.#{page_name}")
         else
           @topic.title
         end
       @title = "#{title_prefix} - #{SiteSetting.title}"
       @body = @topic.posts.first.cooked
       @faq_overridden = !SiteSetting.faq_url.blank?
-      @experimental_rename_faq_to_guidelines = SiteSetting.experimental_rename_faq_to_guidelines
+      @experimental_rename_faq_to_guidelines = rename_faq
 
       render :show, layout: !request.xhr?, formats: [:html]
       return