Enable more frozen string in app/controllers/

Enables frozen string for the following:

* app/controllers/dashboard/**/*.rb
* app/controllers/explore/**/*.rb
* app/controllers/google_api/**/*.rb
* app/controllers/groups/**/*.rb
* app/controllers/import/**/*.rb
* app/controllers/instance_statistics/**/*.rb
* app/controllers/ldap/**/*.rb
* app/controllers/oauth/**/*.rb
* app/controllers/profiles/**/*.rb

Partially addresses #47424.

51 files changed, 103 insertions, 1 deletions

diff --git a/app/controllers/dashboard/application_controller.rb b/app/controllers/dashboard/application_controller.rb
index 9fb5c525425..cee0753a021 100644
--- a/app/controllers/dashboard/application_controller.rb
+++ b/app/controllers/dashboard/application_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::ApplicationController < ApplicationController
   include ControllerWithCrossProjectAccessCheck
 
diff --git a/app/controllers/dashboard/groups_controller.rb b/app/controllers/dashboard/groups_controller.rb
index 79f563bef86..f82cde8e10a 100644
--- a/app/controllers/dashboard/groups_controller.rb
+++ b/app/controllers/dashboard/groups_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::GroupsController < Dashboard::ApplicationController
   include GroupTree
 
diff --git a/app/controllers/dashboard/labels_controller.rb b/app/controllers/dashboard/labels_controller.rb
index 9dcb3a0eb6d..89d87c2d5c8 100644
--- a/app/controllers/dashboard/labels_controller.rb
+++ b/app/controllers/dashboard/labels_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::LabelsController < Dashboard::ApplicationController
   def index
     respond_to do |format|
diff --git a/app/controllers/dashboard/milestones_controller.rb b/app/controllers/dashboard/milestones_controller.rb
index 78f7f6d4e23..6e17bc212e4 100644
--- a/app/controllers/dashboard/milestones_controller.rb
+++ b/app/controllers/dashboard/milestones_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::MilestonesController < Dashboard::ApplicationController
   include MilestoneActions
 
diff --git a/app/controllers/dashboard/projects_controller.rb b/app/controllers/dashboard/projects_controller.rb
index e8f796f17ca..e9686ed8d06 100644
--- a/app/controllers/dashboard/projects_controller.rb
+++ b/app/controllers/dashboard/projects_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::ProjectsController < Dashboard::ApplicationController
   include ParamsBackwardCompatibility
   include RendersMemberAccess
diff --git a/app/controllers/dashboard/snippets_controller.rb b/app/controllers/dashboard/snippets_controller.rb
index 0ba97e4fd59..161c22046f9 100644
--- a/app/controllers/dashboard/snippets_controller.rb
+++ b/app/controllers/dashboard/snippets_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::SnippetsController < Dashboard::ApplicationController
   skip_cross_project_access_check :index
 
diff --git a/app/controllers/dashboard/todos_controller.rb b/app/controllers/dashboard/todos_controller.rb
index 231a23427f7..b82caf30a91 100644
--- a/app/controllers/dashboard/todos_controller.rb
+++ b/app/controllers/dashboard/todos_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Dashboard::TodosController < Dashboard::ApplicationController
   include ActionView::Helpers::NumberHelper
 
diff --git a/app/controllers/explore/application_controller.rb b/app/controllers/explore/application_controller.rb
index baf54520b9c..8eee3742d89 100644
--- a/app/controllers/explore/application_controller.rb
+++ b/app/controllers/explore/application_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Explore::ApplicationController < ApplicationController
   skip_before_action :authenticate_user!
 
diff --git a/app/controllers/explore/groups_controller.rb b/app/controllers/explore/groups_controller.rb
index fa0a0f68fbc..67db797b80a 100644
--- a/app/controllers/explore/groups_controller.rb
+++ b/app/controllers/explore/groups_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Explore::GroupsController < Explore::ApplicationController
   include GroupTree
 
diff --git a/app/controllers/explore/projects_controller.rb b/app/controllers/explore/projects_controller.rb
index 03a2ee07fea..7ecbc32cf4e 100644
--- a/app/controllers/explore/projects_controller.rb
+++ b/app/controllers/explore/projects_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Explore::ProjectsController < Explore::ApplicationController
   include ParamsBackwardCompatibility
   include RendersMemberAccess
diff --git a/app/controllers/explore/snippets_controller.rb b/app/controllers/explore/snippets_controller.rb
index d3f0e033068..76ed142c939 100644
--- a/app/controllers/explore/snippets_controller.rb
+++ b/app/controllers/explore/snippets_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Explore::SnippetsController < Explore::ApplicationController
   def index
     @snippets = SnippetsFinder.new(current_user).execute
diff --git a/app/controllers/google_api/authorizations_controller.rb b/app/controllers/google_api/authorizations_controller.rb
index 5551057ff55..dd9f5af61b3 100644
--- a/app/controllers/google_api/authorizations_controller.rb
+++ b/app/controllers/google_api/authorizations_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module GoogleApi
   class AuthorizationsController < ApplicationController
     def callback
diff --git a/app/controllers/groups/application_controller.rb b/app/controllers/groups/application_controller.rb
index 62213561898..5f92333c2c3 100644
--- a/app/controllers/groups/application_controller.rb
+++ b/app/controllers/groups/application_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::ApplicationController < ApplicationController
   include RoutableActions
   include ControllerWithCrossProjectAccessCheck
diff --git a/app/controllers/groups/avatars_controller.rb b/app/controllers/groups/avatars_controller.rb
index 35a61b359c8..8e4dc2bb6e9 100644
--- a/app/controllers/groups/avatars_controller.rb
+++ b/app/controllers/groups/avatars_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::AvatarsController < Groups::ApplicationController
   before_action :authorize_admin_group!
 
diff --git a/app/controllers/groups/boards_controller.rb b/app/controllers/groups/boards_controller.rb
index e892d1f8dbf..8d259b4052e 100644
--- a/app/controllers/groups/boards_controller.rb
+++ b/app/controllers/groups/boards_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::BoardsController < Groups::ApplicationController
   include BoardsResponses
 
diff --git a/app/controllers/groups/children_controller.rb b/app/controllers/groups/children_controller.rb
index 0e8125d6113..d549f793ad7 100644
--- a/app/controllers/groups/children_controller.rb
+++ b/app/controllers/groups/children_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Groups
   class ChildrenController < Groups::ApplicationController
     before_action :group
diff --git a/app/controllers/groups/group_members_controller.rb b/app/controllers/groups/group_members_controller.rb
index 7dc51f4c357..0bc082246a1 100644
--- a/app/controllers/groups/group_members_controller.rb
+++ b/app/controllers/groups/group_members_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::GroupMembersController < Groups::ApplicationController
   include MembershipActions
   include MembersPresentation
diff --git a/app/controllers/groups/labels_controller.rb b/app/controllers/groups/labels_controller.rb
index 059cf160fa2..129a197ec9d 100644
--- a/app/controllers/groups/labels_controller.rb
+++ b/app/controllers/groups/labels_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::LabelsController < Groups::ApplicationController
   include ToggleSubscriptionAction
 
diff --git a/app/controllers/groups/milestones_controller.rb b/app/controllers/groups/milestones_controller.rb
index 6bdc0f79ef2..a7cee426cf1 100644
--- a/app/controllers/groups/milestones_controller.rb
+++ b/app/controllers/groups/milestones_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::MilestonesController < Groups::ApplicationController
   include MilestoneActions
 
diff --git a/app/controllers/groups/runners_controller.rb b/app/controllers/groups/runners_controller.rb
index 1036b4e6ed3..dd8fbf7a029 100644
--- a/app/controllers/groups/runners_controller.rb
+++ b/app/controllers/groups/runners_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::RunnersController < Groups::ApplicationController
   # Proper policies should be implemented per
   # https://gitlab.com/gitlab-org/gitlab-ce/issues/45894
diff --git a/app/controllers/groups/settings/ci_cd_controller.rb b/app/controllers/groups/settings/ci_cd_controller.rb
index 4bf6a2a3ad1..6d9a225b771 100644
--- a/app/controllers/groups/settings/ci_cd_controller.rb
+++ b/app/controllers/groups/settings/ci_cd_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Groups
   module Settings
     class CiCdController < Groups::ApplicationController
diff --git a/app/controllers/groups/shared_projects_controller.rb b/app/controllers/groups/shared_projects_controller.rb
index 7dec1f5f402..30b7bfc70ae 100644
--- a/app/controllers/groups/shared_projects_controller.rb
+++ b/app/controllers/groups/shared_projects_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Groups
   class SharedProjectsController < Groups::ApplicationController
     respond_to :json
diff --git a/app/controllers/groups/uploads_controller.rb b/app/controllers/groups/uploads_controller.rb
index 74760194a1f..7e5cdae0ce3 100644
--- a/app/controllers/groups/uploads_controller.rb
+++ b/app/controllers/groups/uploads_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Groups::UploadsController < Groups::ApplicationController
   include UploadsActions
   include WorkhorseRequest
diff --git a/app/controllers/groups/variables_controller.rb b/app/controllers/groups/variables_controller.rb
index 4d8a20de017..4f641de0357 100644
--- a/app/controllers/groups/variables_controller.rb
+++ b/app/controllers/groups/variables_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Groups
   class VariablesController < Groups::ApplicationController
     before_action :authorize_admin_build!
diff --git a/app/controllers/import/base_controller.rb b/app/controllers/import/base_controller.rb
index 14b8c6e4137..042b6b1264f 100644
--- a/app/controllers/import/base_controller.rb
+++ b/app/controllers/import/base_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::BaseController < ApplicationController
   private
 
diff --git a/app/controllers/import/bitbucket_controller.rb b/app/controllers/import/bitbucket_controller.rb
index f885e04b198..1b30b4dda36 100644
--- a/app/controllers/import/bitbucket_controller.rb
+++ b/app/controllers/import/bitbucket_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::BitbucketController < Import::BaseController
   before_action :verify_bitbucket_import_enabled
   before_action :bitbucket_auth, except: :callback
diff --git a/app/controllers/import/fogbugz_controller.rb b/app/controllers/import/fogbugz_controller.rb
index df96d181153..5a439e6de78 100644
--- a/app/controllers/import/fogbugz_controller.rb
+++ b/app/controllers/import/fogbugz_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::FogbugzController < Import::BaseController
   before_action :verify_fogbugz_import_enabled
   before_action :user_map, only: [:new_user_map, :create_user_map]
diff --git a/app/controllers/import/gitea_controller.rb b/app/controllers/import/gitea_controller.rb
index fbd851c64a7..382c684a408 100644
--- a/app/controllers/import/gitea_controller.rb
+++ b/app/controllers/import/gitea_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::GiteaController < Import::GithubController
   def new
     if session[access_token_key].present? && session[host_key].present?
diff --git a/app/controllers/import/github_controller.rb b/app/controllers/import/github_controller.rb
index f8b43b4fde5..1dfa814cdd5 100644
--- a/app/controllers/import/github_controller.rb
+++ b/app/controllers/import/github_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::GithubController < Import::BaseController
   before_action :verify_import_enabled
   before_action :provider_auth, only: [:status, :jobs, :create]
diff --git a/app/controllers/import/gitlab_controller.rb b/app/controllers/import/gitlab_controller.rb
index bdc402b0a77..498de0b07b8 100644
--- a/app/controllers/import/gitlab_controller.rb
+++ b/app/controllers/import/gitlab_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::GitlabController < Import::BaseController
   MAX_PROJECT_PAGES = 15
   PER_PAGE_PROJECTS = 100
diff --git a/app/controllers/import/gitlab_projects_controller.rb b/app/controllers/import/gitlab_projects_controller.rb
index f21c38a4c27..354fba5d204 100644
--- a/app/controllers/import/gitlab_projects_controller.rb
+++ b/app/controllers/import/gitlab_projects_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::GitlabProjectsController < Import::BaseController
   before_action :whitelist_query_limiting, only: [:create]
   before_action :verify_gitlab_project_import_enabled
diff --git a/app/controllers/import/google_code_controller.rb b/app/controllers/import/google_code_controller.rb
index e9387d0ad14..331f06c3dd6 100644
--- a/app/controllers/import/google_code_controller.rb
+++ b/app/controllers/import/google_code_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::GoogleCodeController < Import::BaseController
   before_action :verify_google_code_import_enabled
   before_action :user_map, only: [:new_user_map, :create_user_map]
diff --git a/app/controllers/import/manifest_controller.rb b/app/controllers/import/manifest_controller.rb
index 4ed9dca2475..320cd45b925 100644
--- a/app/controllers/import/manifest_controller.rb
+++ b/app/controllers/import/manifest_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Import::ManifestController < Import::BaseController
   before_action :whitelist_query_limiting, only: [:create]
   before_action :verify_import_enabled
diff --git a/app/controllers/ldap/omniauth_callbacks_controller.rb b/app/controllers/ldap/omniauth_callbacks_controller.rb
index fb24edb8602..5e872804448 100644
--- a/app/controllers/ldap/omniauth_callbacks_controller.rb
+++ b/app/controllers/ldap/omniauth_callbacks_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Ldap::OmniauthCallbacksController < OmniauthCallbacksController
   extend ::Gitlab::Utils::Override
 
diff --git a/app/controllers/oauth/applications_controller.rb b/app/controllers/oauth/applications_controller.rb
index 9e700f648f4..b50f140dc80 100644
--- a/app/controllers/oauth/applications_controller.rb
+++ b/app/controllers/oauth/applications_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Oauth::ApplicationsController < Doorkeeper::ApplicationsController
   include Gitlab::GonHelper
   include Gitlab::Allowable
diff --git a/app/controllers/oauth/authorizations_controller.rb b/app/controllers/oauth/authorizations_controller.rb
index 05190103767..894a6a431e3 100644
--- a/app/controllers/oauth/authorizations_controller.rb
+++ b/app/controllers/oauth/authorizations_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Oauth::AuthorizationsController < Doorkeeper::AuthorizationsController
   layout 'profile'
 
diff --git a/app/controllers/oauth/authorized_applications_controller.rb b/app/controllers/oauth/authorized_applications_controller.rb
index 656107d2b26..a59ade559b3 100644
--- a/app/controllers/oauth/authorized_applications_controller.rb
+++ b/app/controllers/oauth/authorized_applications_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Oauth::AuthorizedApplicationsController < Doorkeeper::AuthorizedApplicationsController
   include PageLayoutHelper
 
diff --git a/app/controllers/profiles/accounts_controller.rb b/app/controllers/profiles/accounts_controller.rb
index fd9cb9fca3e..cb3180f4196 100644
--- a/app/controllers/profiles/accounts_controller.rb
+++ b/app/controllers/profiles/accounts_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::AccountsController < Profiles::ApplicationController
   include AuthHelper
 
diff --git a/app/controllers/profiles/active_sessions_controller.rb b/app/controllers/profiles/active_sessions_controller.rb
index f1e77d68acd..efe7ede5efa 100644
--- a/app/controllers/profiles/active_sessions_controller.rb
+++ b/app/controllers/profiles/active_sessions_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::ActiveSessionsController < Profiles::ApplicationController
   def index
     @sessions = ActiveSession.list(current_user)
diff --git a/app/controllers/profiles/application_controller.rb b/app/controllers/profiles/application_controller.rb
index c8be288b9a0..52b046ef64f 100644
--- a/app/controllers/profiles/application_controller.rb
+++ b/app/controllers/profiles/application_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::ApplicationController < ApplicationController
   layout 'profile'
 end
diff --git a/app/controllers/profiles/avatars_controller.rb b/app/controllers/profiles/avatars_controller.rb
index 4f030ded80f..3378a09628c 100644
--- a/app/controllers/profiles/avatars_controller.rb
+++ b/app/controllers/profiles/avatars_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::AvatarsController < Profiles::ApplicationController
   def destroy
     @user = current_user
diff --git a/app/controllers/profiles/chat_names_controller.rb b/app/controllers/profiles/chat_names_controller.rb
index a186c5f36a8..2e78b9e6dc7 100644
--- a/app/controllers/profiles/chat_names_controller.rb
+++ b/app/controllers/profiles/chat_names_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::ChatNamesController < Profiles::ApplicationController
   before_action :chat_name_token, only: [:new]
   before_action :chat_name_params, only: [:new, :create, :deny]
diff --git a/app/controllers/profiles/emails_controller.rb b/app/controllers/profiles/emails_controller.rb
index a39824ec9c8..503eda250b4 100644
--- a/app/controllers/profiles/emails_controller.rb
+++ b/app/controllers/profiles/emails_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::EmailsController < Profiles::ApplicationController
   before_action :find_email, only: [:destroy, :resend_confirmation_instructions]
 
diff --git a/app/controllers/profiles/gpg_keys_controller.rb b/app/controllers/profiles/gpg_keys_controller.rb
index c32507756e8..8c34a66c374 100644
--- a/app/controllers/profiles/gpg_keys_controller.rb
+++ b/app/controllers/profiles/gpg_keys_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::GpgKeysController < Profiles::ApplicationController
   before_action :set_gpg_key, only: [:destroy, :revoke]
 
diff --git a/app/controllers/profiles/keys_controller.rb b/app/controllers/profiles/keys_controller.rb
index 6035258667e..01801c31327 100644
--- a/app/controllers/profiles/keys_controller.rb
+++ b/app/controllers/profiles/keys_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::KeysController < Profiles::ApplicationController
   skip_before_action :authenticate_user!, only: [:get_keys]
 
diff --git a/app/controllers/profiles/notifications_controller.rb b/app/controllers/profiles/notifications_controller.rb
index 00bd2040b9a..b719b70c56e 100644
--- a/app/controllers/profiles/notifications_controller.rb
+++ b/app/controllers/profiles/notifications_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::NotificationsController < Profiles::ApplicationController
   # rubocop: disable CodeReuse/ActiveRecord
   def show
diff --git a/app/controllers/profiles/passwords_controller.rb b/app/controllers/profiles/passwords_controller.rb
index b8ccc6e3c99..a0391d677c4 100644
--- a/app/controllers/profiles/passwords_controller.rb
+++ b/app/controllers/profiles/passwords_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::PasswordsController < Profiles::ApplicationController
   skip_before_action :check_password_expiration, only: [:new, :create]
   skip_before_action :check_two_factor_requirement, only: [:new, :create]
diff --git a/app/controllers/profiles/personal_access_tokens_controller.rb b/app/controllers/profiles/personal_access_tokens_controller.rb
index b357741e3fb..4b6ec2697b7 100644
--- a/app/controllers/profiles/personal_access_tokens_controller.rb
+++ b/app/controllers/profiles/personal_access_tokens_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::PersonalAccessTokensController < Profiles::ApplicationController
   def index
     set_index_vars
diff --git a/app/controllers/profiles/preferences_controller.rb b/app/controllers/profiles/preferences_controller.rb
index ed0f98179eb..37ac11dc6a1 100644
--- a/app/controllers/profiles/preferences_controller.rb
+++ b/app/controllers/profiles/preferences_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::PreferencesController < Profiles::ApplicationController
   before_action :user
 
diff --git a/app/controllers/profiles/two_factor_auths_controller.rb b/app/controllers/profiles/two_factor_auths_controller.rb
index 29ff18a1219..ba94196b2f9 100644
--- a/app/controllers/profiles/two_factor_auths_controller.rb
+++ b/app/controllers/profiles/two_factor_auths_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::TwoFactorAuthsController < Profiles::ApplicationController
   skip_before_action :check_two_factor_requirement
 
@@ -30,7 +32,7 @@ class Profiles::TwoFactorAuthsController < Profiles::ApplicationController
 
       unless two_factor_grace_period_expired?
         grace_period_deadline = current_user.otp_grace_period_started_at + two_factor_grace_period.hours
-        flash.now[:alert] << " You need to do this before #{l(grace_period_deadline)}."
+        flash.now[:alert] = flash.now[:alert] + " You need to do this before #{l(grace_period_deadline)}."
       end
     end
 
diff --git a/app/controllers/profiles/u2f_registrations_controller.rb b/app/controllers/profiles/u2f_registrations_controller.rb
index e3d7737f44a..e6a154fb6aa 100644
--- a/app/controllers/profiles/u2f_registrations_controller.rb
+++ b/app/controllers/profiles/u2f_registrations_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Profiles::U2fRegistrationsController < Profiles::ApplicationController
   def destroy
     u2f_registration = current_user.u2f_registrations.find(params[:id])