DEV: enable frozen string literal on all files

This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.

Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging

.rubocop.yml

@@ -12,6 +12,9 @@ AllCops:
 Style/AndOr:
   Enabled: true
 
+Style/FrozenStringLiteralComment:
+  Enabled: true
+
 # Do not use braces for hash literals when they are the last argument of a
 # method call.
 Style/BracesAroundHashParameters:

Brewfile

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Install development dependencies on Mac OS X using Homebrew (http://mxcl.github.com/homebrew)
 
 # you probably already have git installed; ensure that it is the latest version

Dangerfile

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 if github.pr_json && (github.pr_json["additions"] || 0) > 250 || (github.pr_json["deletions"] || 0) > 250
   warn("This pull request is big! We prefer smaller PRs whenever possible, as they are easier to review. Can this be split into a few smaller PRs?")
 end

Gemfile

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 # if there is a super emergency and rubygems is playing up, try
 #source 'http://production.cf.rubygems.org'

Rakefile

@@ -1,4 +1,6 @@
 #!/usr/bin/env rake
+# frozen_string_literal: true
+
 # Add your own tasks in files placed in lib/tasks ending in .rake,
 # for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
 

app/controllers/about_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'rate_limiter'
 
 class AboutController < ApplicationController

app/controllers/admin/emojis_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'upload_creator'
 
 class Admin::EmojisController < Admin::AdminController

app/controllers/admin/flagged_topics_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'flag_query'
 
 class Admin::FlaggedTopicsController < Admin::AdminController

app/controllers/admin/flags_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'flag_query'
 
 class Admin::FlagsController < Admin::AdminController

app/controllers/admin/groups_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::GroupsController < Admin::AdminController
   def bulk
   end

app/controllers/admin/impersonate_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::ImpersonateController < Admin::AdminController
 
   def create

app/controllers/admin/permalinks_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::PermalinksController < Admin::AdminController
 
   before_action :fetch_permalink, only: [:destroy]

app/controllers/admin/plugins_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::PluginsController < Admin::AdminController
 
   def index

app/controllers/admin/reports_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'report'
 
 class Admin::ReportsController < Admin::AdminController

app/controllers/admin/screened_emails_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::ScreenedEmailsController < Admin::AdminController
 
   def index

app/controllers/admin/screened_ip_addresses_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'ip_addr'
 
 class Admin::ScreenedIpAddressesController < Admin::AdminController

app/controllers/admin/screened_urls_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::ScreenedUrlsController < Admin::AdminController
 
   def index

app/controllers/admin/search_logs_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::SearchLogsController < Admin::AdminController
 
   def index

app/controllers/admin/site_settings_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::SiteSettingsController < Admin::AdminController
   rescue_from Discourse::InvalidParameters do |e|
     render_json_error e.message, status: 422

app/controllers/admin/site_texts_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'seed_data/categories'
 require_dependency 'seed_data/topics'
 

app/controllers/admin/staff_action_logs_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::StaffActionLogsController < Admin::AdminController
 
   def index
@@ -22,7 +24,7 @@ class Admin::StaffActionLogsController < Admin::AdminController
 
     diff_fields = {}
 
-    output = "<h2>#{CGI.escapeHTML(cur["name"].to_s)}</h2><p></p>"
+    output = +"<h2>#{CGI.escapeHTML(cur["name"].to_s)}</h2><p></p>"
 
     diff_fields["name"] = {
       prev: prev["name"].to_s,

app/controllers/admin/themes_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'upload_creator'
 require_dependency 'theme_store/tgz_exporter'
 require 'base64'

app/controllers/admin/user_fields_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::UserFieldsController < Admin::AdminController
 
   def self.columns

app/controllers/admin/users_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'user_destroyer'
 require_dependency 'admin_user_index_query'
 require_dependency 'admin_confirmation'

app/controllers/admin/versions_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'discourse_updates'
 
 class Admin::VersionsController < Admin::AdminController

app/controllers/admin/watched_words_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::WatchedWordsController < Admin::AdminController
 
   def index

app/controllers/admin/web_hooks_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Admin::WebHooksController < Admin::AdminController
   before_action :fetch_web_hook, only: %i(show update destroy list_events bulk_events ping)
 

app/controllers/badges_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class BadgesController < ApplicationController
   skip_before_action :check_xhr, only: [:index, :show]
 

app/controllers/categories_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'category_serializer'
 
 class CategoriesController < ApplicationController

app/controllers/category_hashtags_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CategoryHashtagsController < ApplicationController
   requires_login
 

app/controllers/clicks_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ClicksController < ApplicationController
   skip_before_action :check_xhr, :preload_json, :verify_authenticity_token
 

app/controllers/composer_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'html_to_markdown'
 
 class ComposerController < ApplicationController

app/controllers/composer_messages_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'composer_messages_finder'
 
 class ComposerMessagesController < ApplicationController

app/controllers/directory_items_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class DirectoryItemsController < ApplicationController
   PAGE_SIZE = 50
 

app/controllers/draft_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class DraftController < ApplicationController
   requires_login
 

app/controllers/drafts_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class DraftsController < ApplicationController
   requires_login
 

app/controllers/email_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class EmailController < ApplicationController
   layout 'no_ember'
 

app/controllers/embed_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class EmbedController < ApplicationController
   skip_before_action :check_xhr, :preload_json, :verify_authenticity_token
 

app/controllers/exceptions_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ExceptionsController < ApplicationController
   skip_before_action :check_xhr, :preload_json
   before_action :hide_search

app/controllers/export_csv_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ExportCsvController < ApplicationController
 
   skip_before_action :preload_json, :check_xhr, only: [:show]

app/controllers/finish_installation_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class FinishInstallationController < ApplicationController
   skip_before_action :check_xhr, :preload_json, :redirect_to_login_if_required
   layout 'finish_installation'

app/controllers/groups_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class GroupsController < ApplicationController
   include ApplicationHelper
 

app/controllers/highlight_js_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class HighlightJsController < ApplicationController
   skip_before_action :preload_json, :redirect_to_login_if_required, :check_xhr, :verify_authenticity_token, only: [:show]
 

app/controllers/inline_onebox_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'inline_oneboxer'
 
 class InlineOneboxController < ApplicationController

app/controllers/invites_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'rate_limiter'
 
 class InvitesController < ApplicationController

app/controllers/list_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'topic_list_responder'
 
 class ListController < ApplicationController

app/controllers/notifications_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'notification_serializer'
 
 class NotificationsController < ApplicationController

app/controllers/offline_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class OfflineController < ApplicationController
   layout false
   skip_before_action :preload_json, :check_xhr, :redirect_to_login_if_required

app/controllers/onebox_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'oneboxer'
 
 class OneboxController < ApplicationController

app/controllers/permalinks_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PermalinksController < ApplicationController
   skip_before_action :check_xhr, :preload_json
 

app/controllers/post_action_users_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'discourse'
 
 class PostActionUsersController < ApplicationController

app/controllers/post_actions_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'discourse'
 
 class PostActionsController < ApplicationController

app/controllers/posts_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'new_post_manager'
 require_dependency 'post_creator'
 require_dependency 'post_action_destroyer'
@@ -762,7 +764,7 @@ class PostsController < ApplicationController
   end
 
   def signature_for(args)
-    "post##" << Digest::SHA1.hexdigest(args
+    +"post##" << Digest::SHA1.hexdigest(args
       .to_h
       .to_a
       .concat([["user", current_user.id]])

app/controllers/push_notification_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class PushNotificationController < ApplicationController
   layout false
   before_action :ensure_logged_in

app/controllers/queued_posts_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'queued_post_serializer'
 
 class QueuedPostsController < ApplicationController

app/controllers/qunit_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class QunitController < ApplicationController
   skip_before_action :check_xhr, :preload_json, :redirect_to_login_if_required
   layout false

app/controllers/robots_txt_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class RobotsTxtController < ApplicationController
   layout false
   skip_before_action :preload_json, :check_xhr, :redirect_to_login_if_required

app/controllers/safe_mode_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class SafeModeController < ApplicationController
   layout 'no_ember'
   before_action :ensure_safe_mode_enabled

app/controllers/search_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'search'
 
 class SearchController < ApplicationController

app/controllers/session_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'rate_limiter'
 require_dependency 'single_sign_on'
 require_dependency 'single_sign_on_provider'

app/controllers/similar_topics_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'similar_topic_serializer'
 require_dependency 'search/grouped_search_results'
 

app/controllers/site_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'site_serializer'
 
 class SiteController < ApplicationController

app/controllers/static_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'distributed_memoizer'
 require_dependency 'file_helper'
 
@@ -35,7 +37,7 @@ class StaticController < ApplicationController
     @page = 'faq' if @page == 'guidelines'
 
     # Don't allow paths like ".." or "/" or anything hacky like that
-    @page.gsub!(/[^a-z0-9\_\-]/, '')
+    @page = @page.gsub(/[^a-z0-9\_\-]/, '')
 
     if map.has_key?(@page)
       @topic = Topic.find_by_id(SiteSetting.get(map[@page][:topic_id]))

app/controllers/steps_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'wizard'
 require_dependency 'wizard/builder'
 require_dependency 'wizard/step_updater'

app/controllers/stylesheets_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class StylesheetsController < ApplicationController
   skip_before_action :preload_json, :redirect_to_login_if_required, :check_xhr, :verify_authenticity_token, only: [:show, :show_source_map]
 

app/controllers/tag_groups_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class TagGroupsController < ApplicationController
 
   requires_login

app/controllers/tags_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'topic_list_responder'
 require_dependency 'topics_bulk_action'
 require_dependency 'topic_query'

app/controllers/themes_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ThemesController < ::ApplicationController
   def assets
     theme_ids = params[:ids].to_s.split("-").map(&:to_i)

app/controllers/topics_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'topic_view'
 require_dependency 'promotion'
 require_dependency 'url_helper'

app/controllers/uploads_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "mini_mime"
 require_dependency 'upload_creator'
 

app/controllers/user_actions_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class UserActionsController < ApplicationController
 
   def index

app/controllers/user_api_keys_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class UserApiKeysController < ApplicationController
 
   layout 'no_ember'
@@ -91,7 +93,7 @@ class UserApiKeysController < ApplicationController
     end
 
     if params[:auth_redirect]
-      redirect_path = "#{params[:auth_redirect]}?payload=#{CGI.escape(@payload)}"
+      redirect_path = +"#{params[:auth_redirect]}?payload=#{CGI.escape(@payload)}"
       redirect_path << "&oneTimePassword=#{CGI.escape(otp_payload)}" if scopes.include?("one_time_password")
       redirect_to(redirect_path)
     else

app/controllers/user_avatars_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'letter_avatar'
 
 class UserAvatarsController < ApplicationController

app/controllers/user_badges_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class UserBadgesController < ApplicationController
   before_action :ensure_badges_enabled
 

app/controllers/users/omniauth_callbacks_controller.rb

@@ -1,4 +1,6 @@
 # -*- encoding : utf-8 -*-
+# frozen_string_literal: true
+
 require_dependency 'email'
 require_dependency 'enum'
 require_dependency 'user_name_suggester'
@@ -58,7 +60,7 @@ class Users::OmniauthCallbacksController < ApplicationController
       end
 
       if parsed && (parsed.host == nil || parsed.host == Discourse.current_hostname)
-        @origin = "#{parsed.path}"
+        @origin = +"#{parsed.path}"
         @origin << "?#{parsed.query}" if parsed.query
       end
     end

app/controllers/users_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'discourse_hub'
 require_dependency 'user_name_suggester'
 require_dependency 'rate_limiter'

app/controllers/users_email_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'rate_limiter'
 require_dependency 'email_validator'
 require_dependency 'email_updater'

app/controllers/webhooks_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "openssl"
 
 class WebhooksController < ActionController::Base

app/controllers/wizard_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'wizard'
 require_dependency 'wizard/builder'
 

app/helpers/common_helper.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module CommonHelper
   def render_google_universal_analytics_code
     if Rails.env.production? && SiteSetting.ga_universal_tracking_code.present?

app/helpers/email_helper.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module EmailHelper
 
   def mailing_list_topic(topic, post_count)

app/helpers/embed_helper.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module EmbedHelper
 
   def embed_post_date(dt)

app/helpers/list_helper.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ListHelper
   def page_links(topic)
     posts = topic.posts_count

app/helpers/topics_helper.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module TopicsHelper
   include ApplicationHelper
 

app/helpers/user_notifications_helper.rb

@@ -1,9 +1,11 @@
+# frozen_string_literal: true
+
 module UserNotificationsHelper
   include GlobalPath
 
   def indent(text, by = 2)
     spacer = " " * by
-    result = ""
+    result = +""
     text.each_line do |line|
       result << spacer << line
     end
@@ -32,7 +34,7 @@ module UserNotificationsHelper
   def first_paragraphs_from(html)
     doc = Nokogiri::HTML(html)
 
-    result = ""
+    result = +""
     length = 0
 
     doc.css('body > p, aside.onebox, body > ul, body > blockquote').each do |node|

app/jobs/base.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
 
   def self.queued

app/jobs/concerns/skippable.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Skippable
   extend ActiveSupport::Concern
 

app/jobs/onceoff.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Jobs::Onceoff < Jobs::Base
   sidekiq_options retry: false
 

app/jobs/onceoff/clean_up_sidekiq_statistic.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class CleanUpSidekiqStatistic < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/clear_width_and_height.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class ClearWidthAndHeight < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/correct_missing_dualstack_urls.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class CorrectMissingDualstackUrls < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/create_tags_search_index.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class CreateTagsSearchIndex < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/fix_featured_link_for_topics.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class FixFeaturedLinkForTopics < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/fix_invalid_gravatar_uploads.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class FixInvalidGravatarUploads < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/fix_invalid_upload_extensions.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency "upload_fixer"
 
 module Jobs

app/jobs/onceoff/fix_out_of_sync_user_uploaded_avatar.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class FixOutOfSyncUserUploadedAvatar < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/fix_posts_read.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class FixPostsRead < Jobs::Onceoff
     def execute_onceoff(args)

app/jobs/onceoff/fix_primary_emails_for_staged_users.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'user_destroyer'
 
 module Jobs

app/jobs/onceoff/fix_retro_anniversary.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_dependency 'jobs/scheduled/grant_anniversary_badges'
 
 module Jobs

app/jobs/onceoff/fix_s3_etags.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jobs
   class FixS3Etags < Jobs::Onceoff