gsub_file Rails.root.join("app/views/layouts/application.html.erb").to_s, //, '' pack_tag = <<-eos <%= javascript_pack_tag 'application' %> <%= stylesheet_pack_tag 'application' %> eos insert_into_file Rails.root.join("app/views/layouts/application.html.erb").to_s, pack_tag, before: " \n" vue_on_rails = <<-eos //= vue-on-rails eos insert_into_file Rails.root.join("app/assets/javascripts/application.js").to_s, vue_on_rails, before: "//= require_tree ."