Fix rubocop issues, introduce usage of frozen literal to improve performance

app/controllers/auth/passwords_controller.rb

+# frozen_string_literal: true
+
 class Auth::PasswordsController < Devise::PasswordsController
   layout 'auth'
 end

app/controllers/auth/registrations_controller.rb

+# frozen_string_literal: true
+
 class Auth::RegistrationsController < Devise::RegistrationsController
   layout 'auth'
 

app/controllers/auth/sessions_controller.rb

+# frozen_string_literal: true
+
 class Auth::SessionsController < Devise::SessionsController
   include Devise::Controllers::Rememberable
 

app/controllers/home_controller.rb

+# frozen_string_literal: true
+
 class HomeController < ApplicationController
   before_action :authenticate_user!
 

app/controllers/media_controller.rb

+# frozen_string_literal: true
+
 class MediaController < ApplicationController
   before_action :set_media_attachment
 

app/controllers/oauth/authorizations_controller.rb

+# frozen_string_literal: true
+
 class Oauth::AuthorizationsController < Doorkeeper::AuthorizationsController
   skip_before_action :authenticate_resource_owner!
 

app/controllers/settings/preferences_controller.rb

+# frozen_string_literal: true
+
 class Settings::PreferencesController < ApplicationController
   layout 'auth'
 

app/controllers/settings/profiles_controller.rb

+# frozen_string_literal: true
+
 class Settings::ProfilesController < ApplicationController
   layout 'auth'
 

app/controllers/stream_entries_controller.rb

+# frozen_string_literal: true
+
 class StreamEntriesController < ApplicationController
   layout 'public'
 
@@ -29,9 +31,7 @@ class StreamEntriesController < ApplicationController
   end
 
   def set_link_headers
-    response.headers['Link'] = LinkHeader.new([
-      [account_stream_entry_url(@account, @stream_entry, format: 'atom'), [['rel', 'alternate'], ['type', 'application/atom+xml']]]
-    ])
+    response.headers['Link'] = LinkHeader.new([[account_stream_entry_url(@account, @stream_entry, format: 'atom'), [%w(rel alternate), %w(type application/atom+xml)]]])
   end
 
   def set_stream_entry

app/controllers/tags_controller.rb

+# frozen_string_literal: true
+
 class TagsController < ApplicationController
   layout 'public'
 

app/controllers/xrd_controller.rb

+# frozen_string_literal: true
+
 class XrdController < ApplicationController
   before_action :set_default_format_json, only: :webfinger
   before_action :set_default_format_xml, only: :host_meta
@@ -26,11 +28,11 @@ class XrdController < ApplicationController
   private
 
   def set_default_format_xml
-    request.format = 'xml' if request.headers["HTTP_ACCEPT"].nil? && params[:format].nil?
+    request.format = 'xml' if request.headers['HTTP_ACCEPT'].nil? && params[:format].nil?
   end
 
   def set_default_format_json
-    request.format = 'json' if request.headers["HTTP_ACCEPT"].nil? && params[:format].nil?
+    request.format = 'json' if request.headers['HTTP_ACCEPT'].nil? && params[:format].nil?
   end
 
   def username_from_resource
@@ -44,14 +46,14 @@ class XrdController < ApplicationController
 
   def pem_to_magic_key(public_key)
     modulus, exponent = [public_key.n, public_key.e].map do |component|
-      result = ''
+      result = []
 
       until component.zero?
         result << [component % 256].pack('C')
         component >>= 8
       end
 
-      result.reverse!
+      result.reverse.join
     end
 
     (['RSA'] + [modulus, exponent].map { |n| Base64.urlsafe_encode64(n) }).join('.')

app/helpers/about_helper.rb

+# frozen_string_literal: true
+
 module AboutHelper
 end

app/helpers/accounts_helper.rb

+# frozen_string_literal: true
+
 module AccountsHelper
   def pagination_options
     {
-      previous_label: "#{fa_icon('chevron-left')} Prev".html_safe,
-      next_label: "Next #{fa_icon('chevron-right')}".html_safe,
+      previous_label: safe_join([fa_icon('chevron-left'), 'Prev'], ' '),
+      next_label: safe_join(['Next', fa_icon('chevron-right')], ' '),
       inner_window: 1,
-      outer_window: 0
+      outer_window: 0,
     }
   end
 end

app/helpers/application_helper.rb

+# frozen_string_literal: true
+
 module ApplicationHelper
   def active_nav_class(path)
     current_page?(path) ? 'active' : ''

app/helpers/atom_builder_helper.rb

+# frozen_string_literal: true
+
 module AtomBuilderHelper
   def stream_updated_at
-    @account.stream_entries.last ? (@account.updated_at > @account.stream_entries.last.created_at ? @account.updated_at : @account.stream_entries.last.created_at) : @account.updated_at
+    if @account.stream_entries.last
+      (@account.updated_at > @account.stream_entries.last.created_at ? @account.updated_at : @account.stream_entries.last.created_at)
+    else
+      @account.updated_at
+    end
   end
 
   def entry(xml, is_root = false, &block)
@@ -98,7 +104,7 @@ module AtomBuilderHelper
   end
 
   def in_reply_to(xml, uri, url)
-    xml['thr'].send('in-reply-to', { ref: uri, href: url, type: 'text/html' })
+    xml['thr'].send('in-reply-to', ref: uri, href: url, type: 'text/html')
   end
 
   def link_mention(xml, account)

app/helpers/home_helper.rb

+# frozen_string_literal: true
+
 module HomeHelper
   def default_props
     {
       token: @token,
-      account: render(file: 'api/v1/accounts/show', locals: { account: current_user.account }, formats: :json)
+      account: render(file: 'api/v1/accounts/show', locals: { account: current_user.account }, formats: :json),
     }
   end
 end

app/helpers/routing_helper.rb

+# frozen_string_literal: true
+
 module RoutingHelper
   extend ActiveSupport::Concern
   include Rails.application.routes.url_helpers

app/helpers/stream_entries_helper.rb

+# frozen_string_literal: true
+
 module StreamEntriesHelper
   def display_name(account)
     account.display_name.blank? ? account.username : account.display_name

app/helpers/tags_helper.rb

+# frozen_string_literal: true
+
 module TagsHelper
 end

app/helpers/xrd_helper.rb

+# frozen_string_literal: true
+
 module XrdHelper
 end