Enable frozen string in app/controllers/**/*.rb

Enables frozen string for the following:

* app/controllers/*.rb
* app/controllers/admin/**/*.rb
* app/controllers/boards/**/*.rb
* app/controllers/ci/**/*.rb
* app/controllers/concerns/**/*.rb

Partially addresses #47424.

app/controllers/abuse_reports_controller.rb

+# frozen_string_literal: true
+
 class AbuseReportsController < ApplicationController
   before_action :set_user, only: [:new]
 

app/controllers/admin/abuse_reports_controller.rb

+# frozen_string_literal: true
+
 class Admin::AbuseReportsController < Admin::ApplicationController
   # rubocop: disable CodeReuse/ActiveRecord
   def index

app/controllers/admin/appearances_controller.rb

+# frozen_string_literal: true
+
 class Admin::AppearancesController < Admin::ApplicationController
   prepend EE::Admin::AppearancesController
 

app/controllers/admin/application_controller.rb

+# frozen_string_literal: true
+
 # Provides a base class for Admin controllers to subclass
 #
 # Automatically sets the layout and ensures an administrator is logged in

app/controllers/admin/application_settings_controller.rb

+# frozen_string_literal: true
+
 class Admin::ApplicationSettingsController < Admin::ApplicationController
   prepend EE::Admin::ApplicationSettingsController
 

app/controllers/admin/applications_controller.rb

+# frozen_string_literal: true
+
 class Admin::ApplicationsController < Admin::ApplicationController
   include OauthApplications
 

app/controllers/admin/background_jobs_controller.rb

+# frozen_string_literal: true
+
 class Admin::BackgroundJobsController < Admin::ApplicationController
   def show
     ps_output, _ = Gitlab::Popen.popen(%W(ps ww -U #{Gitlab.config.gitlab.user} -o pid,pcpu,pmem,stat,start,command))

app/controllers/admin/broadcast_messages_controller.rb

+# frozen_string_literal: true
+
 class Admin::BroadcastMessagesController < Admin::ApplicationController
   include BroadcastMessagesHelper
 

app/controllers/admin/dashboard_controller.rb

+# frozen_string_literal: true
+
 class Admin::DashboardController < Admin::ApplicationController
   prepend ::EE::Admin::DashboardController
 

app/controllers/admin/deploy_keys_controller.rb

+# frozen_string_literal: true
+
 class Admin::DeployKeysController < Admin::ApplicationController
   before_action :deploy_keys, only: [:index]
   before_action :deploy_key, only: [:destroy, :edit, :update]

app/controllers/admin/gitaly_servers_controller.rb

+# frozen_string_literal: true
+
 class Admin::GitalyServersController < Admin::ApplicationController
   def index
     @gitaly_servers = Gitaly::Server.all

app/controllers/admin/groups_controller.rb

+# frozen_string_literal: true
+
 class Admin::GroupsController < Admin::ApplicationController
   include MembersPresentation
 

app/controllers/admin/health_check_controller.rb

+# frozen_string_literal: true
+
 class Admin::HealthCheckController < Admin::ApplicationController
   def show
     checks = ['standard']

app/controllers/admin/hook_logs_controller.rb

+# frozen_string_literal: true
+
 class Admin::HookLogsController < Admin::ApplicationController
   include HooksExecution
 

app/controllers/admin/hooks_controller.rb

+# frozen_string_literal: true
+
 class Admin::HooksController < Admin::ApplicationController
   include HooksExecution
 

app/controllers/admin/identities_controller.rb

+# frozen_string_literal: true
+
 class Admin::IdentitiesController < Admin::ApplicationController
   before_action :user
   before_action :identity, except: [:index, :new, :create]

app/controllers/admin/impersonation_tokens_controller.rb

+# frozen_string_literal: true
+
 class Admin::ImpersonationTokensController < Admin::ApplicationController
   before_action :user
 

app/controllers/admin/impersonations_controller.rb

+# frozen_string_literal: true
+
 class Admin::ImpersonationsController < Admin::ApplicationController
   skip_before_action :authenticate_admin!
   before_action :authenticate_impersonator!

app/controllers/admin/jobs_controller.rb

+# frozen_string_literal: true
+
 class Admin::JobsController < Admin::ApplicationController
   # rubocop: disable CodeReuse/ActiveRecord
   def index

app/controllers/admin/keys_controller.rb

+# frozen_string_literal: true
+
 class Admin::KeysController < Admin::ApplicationController
   before_action :user, only: [:show, :destroy]
 

app/controllers/admin/labels_controller.rb

+# frozen_string_literal: true
+
 class Admin::LabelsController < Admin::ApplicationController
   before_action :set_label, only: [:show, :edit, :update, :destroy]
 

app/controllers/admin/logs_controller.rb

+# frozen_string_literal: true
+
 class Admin::LogsController < Admin::ApplicationController
   prepend EE::Admin::LogsController
 

app/controllers/admin/projects_controller.rb

+# frozen_string_literal: true
+
 class Admin::ProjectsController < Admin::ApplicationController
   include MembersPresentation
 

app/controllers/admin/requests_profiles_controller.rb

+# frozen_string_literal: true
+
 class Admin::RequestsProfilesController < Admin::ApplicationController
   def index
     @profile_token = Gitlab::RequestProfiler.profile_token

app/controllers/admin/runner_projects_controller.rb

+# frozen_string_literal: true
+
 class Admin::RunnerProjectsController < Admin::ApplicationController
   before_action :project, only: [:create]
 

app/controllers/admin/runners_controller.rb

+# frozen_string_literal: true
+
 class Admin::RunnersController < Admin::ApplicationController
   before_action :runner, except: :index
 

app/controllers/admin/spam_logs_controller.rb

+# frozen_string_literal: true
+
 class Admin::SpamLogsController < Admin::ApplicationController
   # rubocop: disable CodeReuse/ActiveRecord
   def index

app/controllers/admin/system_info_controller.rb

+# frozen_string_literal: true
+
 class Admin::SystemInfoController < Admin::ApplicationController
   EXCLUDED_MOUNT_OPTIONS = [
     'nobrowse',

app/controllers/admin/users_controller.rb

+# frozen_string_literal: true
+
 class Admin::UsersController < Admin::ApplicationController
   prepend EE::Admin::UsersController
 

app/controllers/application_controller.rb

+# frozen_string_literal: true
+
 require 'gon'
 require 'fogbugz'
 

app/controllers/autocomplete_controller.rb

+# frozen_string_literal: true
+
 class AutocompleteController < ApplicationController
   prepend EE::AutocompleteController
 

app/controllers/boards/application_controller.rb

+# frozen_string_literal: true
+
 module Boards
   class ApplicationController < ::ApplicationController
     respond_to :json

app/controllers/boards/issues_controller.rb

+# frozen_string_literal: true
+
 module Boards
   class IssuesController < Boards::ApplicationController
     include BoardsResponses

app/controllers/boards/lists_controller.rb

+# frozen_string_literal: true
+
 module Boards
   class ListsController < Boards::ApplicationController
     prepend ::EE::Boards::ListsController

app/controllers/ci/lints_controller.rb

+# frozen_string_literal: true
+
 module Ci
   class LintsController < ::ApplicationController
     before_action :authenticate_user!

app/controllers/concerns/accepts_pending_invitations.rb

+# frozen_string_literal: true
+
 module AcceptsPendingInvitations
   extend ActiveSupport::Concern
 

app/controllers/concerns/authenticates_with_two_factor.rb

+# frozen_string_literal: true
+
 # == AuthenticatesWithTwoFactor
 #
 # Controller concern to handle two-factor authentication

app/controllers/concerns/boards_responses.rb

+# frozen_string_literal: true
+
 module BoardsResponses
   include Gitlab::Utils::StrongMemoize
 

app/controllers/concerns/checks_collaboration.rb

+# frozen_string_literal: true
+
 module ChecksCollaboration
   def can_collaborate_with_project?(project, ref: nil)
     return true if can?(current_user, :push_code, project)

app/controllers/concerns/continue_params.rb

+# frozen_string_literal: true
+
 module ContinueParams
   include InternalRedirect
   extend ActiveSupport::Concern

app/controllers/concerns/controller_with_cross_project_access_check.rb

+# frozen_string_literal: true
+
 module ControllerWithCrossProjectAccessCheck
   extend ActiveSupport::Concern
 

app/controllers/concerns/creates_commit.rb

+# frozen_string_literal: true
+
 module CreatesCommit
   extend ActiveSupport::Concern
   include Gitlab::Utils::StrongMemoize
@@ -65,7 +67,7 @@ module CreatesCommit
         flash[:notice] = nil
       else
         target = different_project? ? "project" : "branch"
-        flash[:notice] << " You can now submit a merge request to get this change into the original #{target}."
+        flash[:notice] = flash[:notice] + " You can now submit a merge request to get this change into the original #{target}."
       end
     end
   end

app/controllers/concerns/cycle_analytics_params.rb

+# frozen_string_literal: true
+
 module CycleAnalyticsParams
   extend ActiveSupport::Concern
 

app/controllers/concerns/diff_for_path.rb

+# frozen_string_literal: true
+
 module DiffForPath
   extend ActiveSupport::Concern
 

app/controllers/concerns/enforces_two_factor_authentication.rb

+# frozen_string_literal: true
+
 # == EnforcesTwoFactorAuthentication
 #
 # Controller concern to enforce two-factor authentication requirements

app/controllers/concerns/group_tree.rb

+# frozen_string_literal: true
+
 module GroupTree
   # rubocop:disable Gitlab/ModuleWithInstanceVariables
   # rubocop: disable CodeReuse/ActiveRecord

app/controllers/concerns/hooks_execution.rb

+# frozen_string_literal: true
+
 module HooksExecution
   extend ActiveSupport::Concern
 

app/controllers/concerns/internal_redirect.rb

+# frozen_string_literal: true
+
 module InternalRedirect
   prepend EE::InternalRedirect
   extend ActiveSupport::Concern

app/controllers/concerns/issuable_actions.rb

+# frozen_string_literal: true
+
 module IssuableActions
   prepend EE::IssuableActions
   extend ActiveSupport::Concern

app/controllers/concerns/issuable_collections.rb

+# frozen_string_literal: true
+
 module IssuableCollections
   prepend EE::IssuableCollections
   extend ActiveSupport::Concern

app/controllers/concerns/issues_action.rb

+# frozen_string_literal: true
+
 module IssuesAction
   extend ActiveSupport::Concern
   include IssuableCollections

app/controllers/concerns/issues_calendar.rb

+# frozen_string_literal: true
+
 module IssuesCalendar
   extend ActiveSupport::Concern
 

app/controllers/concerns/lfs_request.rb

+# frozen_string_literal: true
+
 # This concern assumes:
 # - a `#project` accessor
 # - a `#user` accessor

app/controllers/concerns/members_presentation.rb

+# frozen_string_literal: true
+
 module MembersPresentation
   extend ActiveSupport::Concern
 

app/controllers/concerns/membership_actions.rb

+# frozen_string_literal: true
+
 module MembershipActions
   include MembersPresentation
   extend ActiveSupport::Concern

app/controllers/concerns/merge_requests_action.rb

+# frozen_string_literal: true
+
 module MergeRequestsAction
   extend ActiveSupport::Concern
   include IssuableCollections

app/controllers/concerns/milestone_actions.rb

+# frozen_string_literal: true
+
 module MilestoneActions
   extend ActiveSupport::Concern
 

app/controllers/concerns/notes_actions.rb

+# frozen_string_literal: true
+
 module NotesActions
   include RendersNotes
   include Gitlab::Utils::StrongMemoize

app/controllers/concerns/oauth_applications.rb

+# frozen_string_literal: true
+
 module OauthApplications
   extend ActiveSupport::Concern
 

app/controllers/concerns/params_backward_compatibility.rb

+# frozen_string_literal: true
+
 module ParamsBackwardCompatibility
   private
 

app/controllers/concerns/preview_markdown.rb

+# frozen_string_literal: true
+
 module PreviewMarkdown
   extend ActiveSupport::Concern
 

app/controllers/concerns/renders_blob.rb

+# frozen_string_literal: true
+
 module RendersBlob
   extend ActiveSupport::Concern
 

app/controllers/concerns/renders_commits.rb

+# frozen_string_literal: true
+
 module RendersCommits
   def limited_commits(commits)
     if commits.size > MergeRequestDiff::COMMITS_SAFE_SIZE

app/controllers/concerns/renders_member_access.rb

+# frozen_string_literal: true
+
 module RendersMemberAccess
   def prepare_groups_for_rendering(groups)
     preload_max_member_access_for_collection(Group, groups)

app/controllers/concerns/renders_notes.rb

+# frozen_string_literal: true
+
 module RendersNotes
   # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def prepare_notes_for_rendering(notes, noteable = nil)

app/controllers/concerns/repository_settings_redirect.rb

+# frozen_string_literal: true
+
 module RepositorySettingsRedirect
   extend ActiveSupport::Concern
 

app/controllers/concerns/requires_whitelisted_monitoring_client.rb

+# frozen_string_literal: true
+
 module RequiresWhitelistedMonitoringClient
   extend ActiveSupport::Concern
 

app/controllers/concerns/routable_actions.rb

+# frozen_string_literal: true
+
 module RoutableActions
   extend ActiveSupport::Concern
 

app/controllers/concerns/send_file_upload.rb

+# frozen_string_literal: true
+
 module SendFileUpload
   def send_upload(file_upload, send_params: {}, redirect_params: {}, attachment: nil, disposition: 'attachment')
     if attachment

app/controllers/concerns/service_params.rb

+# frozen_string_literal: true
+
 module ServiceParams
   extend ActiveSupport::Concern
   prepend EE::ServiceParams

app/controllers/concerns/snippets_actions.rb

+# frozen_string_literal: true
+
 module SnippetsActions
   extend ActiveSupport::Concern
 

app/controllers/concerns/spammable_actions.rb

+# frozen_string_literal: true
+
 module SpammableActions
   extend ActiveSupport::Concern
 

app/controllers/concerns/todos_actions.rb

+# frozen_string_literal: true
+
 module TodosActions
   extend ActiveSupport::Concern
 

app/controllers/concerns/toggle_award_emoji.rb

+# frozen_string_literal: true
+
 module ToggleAwardEmoji
   extend ActiveSupport::Concern
 

app/controllers/concerns/toggle_subscription_action.rb

+# frozen_string_literal: true
+
 module ToggleSubscriptionAction
   extend ActiveSupport::Concern
 

app/controllers/concerns/uploads_actions.rb

+# frozen_string_literal: true
+
 module UploadsActions
   extend ActiveSupport::Concern
 

app/controllers/concerns/with_performance_bar.rb

+# frozen_string_literal: true
+
 module WithPerformanceBar
   extend ActiveSupport::Concern
 

app/controllers/concerns/workhorse_request.rb

+# frozen_string_literal: true
+
 module WorkhorseRequest
   extend ActiveSupport::Concern
 

app/controllers/confirmations_controller.rb

+# frozen_string_literal: true
+
 class ConfirmationsController < Devise::ConfirmationsController
   prepend ::EE::ConfirmationsController
 
@@ -22,7 +24,7 @@ class ConfirmationsController < Devise::ConfirmationsController
       after_sign_in(resource)
     else
       Gitlab::AppLogger.info("Email Confirmed: username=#{resource.username} email=#{resource.email} ip=#{request.remote_ip}")
-      flash[:notice] += " Please sign in."
+      flash[:notice] = flash[:notice] + " Please sign in."
       new_session_path(:user, anchor: 'login-pane')
     end
   end

app/controllers/dashboard_controller.rb

+# frozen_string_literal: true
+
 class DashboardController < Dashboard::ApplicationController
   include IssuesAction
   include MergeRequestsAction

app/controllers/graphql_controller.rb

+# frozen_string_literal: true
+
 class GraphqlController < ApplicationController
   # Unauthenticated users have access to the API for public data
   skip_before_action :authenticate_user!

app/controllers/groups_controller.rb

+# frozen_string_literal: true
+
 class GroupsController < Groups::ApplicationController
   include API::Helpers::RelatedResourcesHelpers
   include IssuesAction

app/controllers/health_check_controller.rb

+# frozen_string_literal: true
+
 class HealthCheckController < HealthCheck::HealthCheckController
   include RequiresWhitelistedMonitoringClient
 end

app/controllers/health_controller.rb

+# frozen_string_literal: true
+
 class HealthController < ActionController::Base
   protect_from_forgery with: :exception, except: :storage_check, prepend: true
   include RequiresWhitelistedMonitoringClient

app/controllers/help_controller.rb

+# frozen_string_literal: true
+
 class HelpController < ApplicationController
   skip_before_action :authenticate_user!
 

app/controllers/ide_controller.rb

+# frozen_string_literal: true
+
 class IdeController < ApplicationController
   layout 'fullscreen'
 

app/controllers/invites_controller.rb

+# frozen_string_literal: true
+
 class InvitesController < ApplicationController
   before_action :member
   skip_before_action :authenticate_user!, only: :decline
@@ -50,9 +52,9 @@ class InvitesController < ApplicationController
   def authenticate_user!
     return if current_user
 
-    notice = "To accept this invitation, sign in"
-    notice << " or create an account" if Gitlab::CurrentSettings.allow_signup?
-    notice << "."
+    notice = ["To accept this invitation, sign in"]
+    notice << "or create an account" if Gitlab::CurrentSettings.allow_signup?
+    notice = notice.join(' ') + "."
 
     store_location_for :user, request.fullpath
     redirect_to new_user_session_path, notice: notice

app/controllers/jwt_controller.rb

+# frozen_string_literal: true
+
 class JwtController < ApplicationController
   skip_before_action :authenticate_user!
   skip_before_action :verify_authenticity_token

app/controllers/koding_controller.rb

+# frozen_string_literal: true
+
 class KodingController < ApplicationController
   before_action :check_integration!
   layout 'koding'

app/controllers/metrics_controller.rb

+# frozen_string_literal: true
+
 class MetricsController < ActionController::Base
   include RequiresWhitelistedMonitoringClient
 

app/controllers/notification_settings_controller.rb

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

app/controllers/omniauth_callbacks_controller.rb

+# frozen_string_literal: true
+
 class OmniauthCallbacksController < Devise::OmniauthCallbacksController
   include AuthenticatesWithTwoFactor
   include Devise::Controllers::Rememberable
@@ -146,14 +148,13 @@ class OmniauthCallbacksController < Devise::OmniauthCallbacksController
 
   def handle_signup_error
     label = Gitlab::Auth::OAuth::Provider.label_for(oauth['provider'])
-    message = "Signing in using your #{label} account without a pre-existing GitLab account is not allowed."
+    message = ["Signing in using your #{label} account without a pre-existing GitLab account is not allowed."]
 
     if Gitlab::CurrentSettings.allow_signup?
-      message << " Create a GitLab account first, and then connect it to your #{label} account."
+      message << "Create a GitLab account first, and then connect it to your #{label} account."
     end
 
     flash[:alert] = message
-
     redirect_to new_user_session_path
   end
 

app/controllers/passwords_controller.rb

+# frozen_string_literal: true
+
 class PasswordsController < Devise::PasswordsController
   skip_before_action :require_no_authentication, only: [:edit, :update]
 

app/controllers/profiles_controller.rb

+# frozen_string_literal: true
+
 class ProfilesController < Profiles::ApplicationController
   include ActionView::Helpers::SanitizeHelper
 

app/controllers/projects_controller.rb

+# frozen_string_literal: true
+
 class ProjectsController < Projects::ApplicationController
   include API::Helpers::RelatedResourcesHelpers
   include IssuableCollections

app/controllers/registrations_controller.rb

+# frozen_string_literal: true
+
 class RegistrationsController < Devise::RegistrationsController
   include Recaptcha::Verify
   include AcceptsPendingInvitations

app/controllers/root_controller.rb

+# frozen_string_literal: true
+
 # RootController
 #
 # This controller exists solely to handle requests to `root_url`. When a user is

app/controllers/search_controller.rb

+# frozen_string_literal: true
+
 class SearchController < ApplicationController
   include ControllerWithCrossProjectAccessCheck
   include SearchHelper

app/controllers/sent_notifications_controller.rb

+# frozen_string_literal: true
+
 class SentNotificationsController < ApplicationController
   prepend EE::SentNotificationsController
 

app/controllers/sessions_controller.rb

+# frozen_string_literal: true
+
 class SessionsController < Devise::SessionsController
   include InternalRedirect
   include AuthenticatesWithTwoFactor