diff --git a/.rubocop_todo/gettext/static_identifier.yml b/.rubocop_todo/gettext/static_identifier.yml
new file mode 100644
index 0000000000000000000000000000000000000000..c330ffe148222cbaa3254419d79238981e4da828
--- /dev/null
+++ b/.rubocop_todo/gettext/static_identifier.yml
@@ -0,0 +1,28 @@
+---
+Gettext/StaticIdentifier:
+ Details: grace period
+ Exclude:
+ - 'app/graphql/types/project_type.rb'
+ - 'app/models/integrations/apple_app_store.rb'
+ - 'app/models/integrations/confluence.rb'
+ - 'app/models/integrations/google_play.rb'
+ - 'app/services/import/fogbugz_service.rb'
+ - 'app/services/issuable_links/create_service.rb'
+ - 'app/services/issues/set_crm_contacts_service.rb'
+ - 'app/services/projects/create_from_template_service.rb'
+ - 'app/services/security/ci_configuration/base_create_service.rb'
+ - 'app/services/users/banned_user_base_service.rb'
+ - 'app/services/work_items/widgets/hierarchy_service/base_service.rb'
+ - 'ee/app/controllers/admin/licenses_controller.rb'
+ - 'ee/app/controllers/subscriptions/groups_controller.rb'
+ - 'ee/app/mailers/ee/emails/admin_notification.rb'
+ - 'ee/app/mailers/emails/namespace_storage_usage_mailer.rb'
+ - 'ee/app/models/ee/member.rb'
+ - 'ee/app/models/integrations/github.rb'
+ - 'ee/app/services/ee/projects/create_from_template_service.rb'
+ - 'ee/app/services/security/security_orchestration_policies/policy_configuration_validation_service.rb'
+ - 'ee/app/services/timebox/rollup_report_service.rb'
+ - 'ee/app/services/timebox_report_service.rb'
+ - 'ee/spec/controllers/groups/security/policies_controller_spec.rb'
+ - 'ee/spec/features/registrations/identity_verification_spec.rb'
+ - 'lib/gitlab/github_import/settings.rb'
diff --git a/rubocop/cop/gettext/static_identifier.rb b/rubocop/cop/gettext/static_identifier.rb
new file mode 100644
index 0000000000000000000000000000000000000000..9ca1c88f4b6b5fabca8c015a4dd804accfaf7100
--- /dev/null
+++ b/rubocop/cop/gettext/static_identifier.rb
@@ -0,0 +1,84 @@
+# frozen_string_literal: true
+
+module RuboCop
+ module Cop
+ module Gettext
+ # Ensure that gettext identifiers are statically defined and not
+ # interpolated, formatted, or concatenated.
+ #
+ # @example
+ #
+ # # bad
+ # _('Hi #{name}')
+ # _('Hi %{name}' % { name: 'Luki' })
+ # _(format('Hi %{name}', name: 'Luki'))
+ #
+ # # good
+ # _('Hi %{name}') % { name: 'Luki' }
+ # format(_('Hi %{name}', name: 'Luki'))
+ #
+ # # also good
+ # var = "Hi"
+ # _(var)
+ # _(some_method_call)
+ # _(CONST)
+ class StaticIdentifier < RuboCop::Cop::Base
+ MSG = 'Ensure to pass static strings to translation method `%{method_name}(...)`.'
+
+ # Number of parameters to check for translation methods.
+ PARAMETERS_TO_CHECK = {
+ _: 1,
+ s_: 1,
+ N_: 1,
+ n_: 2
+ }.freeze
+
+ # RuboCop-specific optimization for `on_send`.
+ RESTRICT_ON_SEND = PARAMETERS_TO_CHECK.keys.freeze
+
+ DENIED_METHOD_CALLS = %i[% format + concat].freeze
+
+ def on_send(node)
+ method_name = node.method_name
+ arguments = node.arguments
+
+ each_invalid_argument(method_name, arguments) do |argument_node|
+ message = format(MSG, method_name: method_name)
+
+ add_offense(argument_node || node, message: message)
+ end
+ end
+
+ private
+
+ def each_invalid_argument(method_name, argument_nodes)
+ number = PARAMETERS_TO_CHECK.fetch(method_name)
+
+ argument_nodes.take(number).each do |argument_node|
+ yield argument_node unless valid_argument?(argument_node)
+ end
+ end
+
+ def valid_argument?(node)
+ return false unless node
+
+ basic_type?(node) || multiline_string?(node) || allowed_method_call?(node)
+ end
+
+ def basic_type?(node)
+ node.str_type? || node.lvar_type? || node.const_type?
+ end
+
+ def multiline_string?(node)
+ node.dstr_type? && node.children.all?(&:str_type?)
+ end
+
+ def allowed_method_call?(node)
+ return false unless node.send_type?
+
+ !DENIED_METHOD_CALLS.include?(node.method_name) # rubocop:disable Rails/NegateInclude
+ end
+ end
+ end
+ end
+end
diff --git a/spec/rubocop/cop/gettext/static_identifier_spec.rb b/spec/rubocop/cop/gettext/static_identifier_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..a0c15d8ad484f6d9b16042f75146e2f63114bd07
--- /dev/null
+++ b/spec/rubocop/cop/gettext/static_identifier_spec.rb
@@ -0,0 +1,174 @@
+# frozen_string_literal: true
+
+require 'rubocop_spec_helper'
+require 'rspec-parameterized'
+
+require_relative '../../../../rubocop/cop/gettext/static_identifier'
+
+RSpec.describe RuboCop::Cop::Gettext::StaticIdentifier, feature_category: :internationalization do
+ describe '#_()' do
+ it 'does not flag correct use' do
+ expect_no_offenses(<<~'RUBY')
+ _('Hello')
+ _('Hello #{name}')
+
+ _('Hello %{name}') % { name: name }
+ format(_('Hello %{name}') % { name: name })
+
+ _('Hello' \
+ 'Multiline')
+ _('Hello' \
+ 'Multiline %{name}') % { name: name }
+
+ var = "Hello"
+ _(var)
+ _(method_name)
+ list.each { |item| _(item) }
+ _(CONST)
+ RUBY
+ end
+
+ it 'flags incorrect use' do
+ expect_offense(<<~'RUBY')
+ _('Hello' + ' concat')
+ ^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `_(...)`.
+ _('Hello'.concat(' concat'))
+ ^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `_(...)`.
+ _("Hello #{name}")
+ ^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `_(...)`.
+ _('Hello %{name}' % { name: name })
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `_(...)`.
+ _(format('Hello %{name}') % { name: name })
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `_(...)`.
+ RUBY
+ end
+ end
+
+ describe '#N_()' do
+ it 'does not flag correct use' do
+ expect_no_offenses(<<~'RUBY')
+ N_('Hello')
+ N_('Hello #{name}')
+ N_('Hello %{name}') % { name: name }
+ format(_('Hello %{name}') % { name: name })
+
+ N_('Hello' \
+ 'Multiline')
+
+ var = "Hello"
+ N_(var)
+ N_(method_name)
+ list.each { |item| N_(item) }
+ N_(CONST)
+ RUBY
+ end
+
+ it 'flags incorrect use' do
+ expect_offense(<<~'RUBY')
+ N_('Hello' + ' concat')
+ ^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `N_(...)`.
+ N_("Hello #{name}")
+ ^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `N_(...)`.
+ N_('Hello %{name}' % { name: name })
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `N_(...)`.
+ N_('Hello' \
+ ^^^^^^^^^ Ensure to pass static strings to translation method `N_(...)`.
+ 'Multiline %{name}' % { name: name })
+ N_(format('Hello %{name}') % { name: name })
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `N_(...)`.
+ RUBY
+ end
+ end
+
+ describe '#s_()' do
+ it 'does not flag correct use' do
+ expect_no_offenses(<<~'RUBY')
+ s_('World|Hello')
+ s_('World|Hello #{name}')
+ s_('World|Hello %{name}') % { name: name }
+ format(s_('World|Hello %{name}') % { name: name })
+
+ s_('World|Hello' \
+ 'Multiline')
+
+ var = "Hello"
+ s_(var)
+ s_(method_name)
+ list.each { |item| s_(item) }
+ s_(CONST)
+ RUBY
+ end
+
+ it 'flags incorrect use' do
+ expect_offense(<<~'RUBY')
+ s_("World|Hello #{name}")
+ ^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `s_(...)`.
+ s_('World|Hello' + ' concat')
+ ^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `s_(...)`.
+ s_('World|Hello %{name}' % { name: name })
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `s_(...)`.
+ s_('World|Hello' \
+ ^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `s_(...)`.
+ 'Multiline %{name}' % { name: name })
+ s_(format('World|Hello %{name}') % { name: name })
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `s_(...)`.
+ RUBY
+ end
+ end
+
+ describe '#n_()' do
+ it 'does not flag correct use' do
+ expect_no_offenses(<<~'RUBY')
+ n_('Hello', 'Hellos', 2)
+ n_('Hello', 'Hellos', count)
+
+ n_('Hello' ' concat', 'Hellos', 2)
+ n_('Hello', 'Hello' 's', 2)
+
+ n_('Hello %{name}', 'Hellos %{name}', 2) % { name: name }
+ format(n_('Hello %{name}', 'Hellos %{name}', count) % { name: name })
+
+ n_('Hello', 'Hellos' \
+ 'Multiline', 2)
+
+ n_('Hello' \
+ 'Multiline', 'Hellos', 2)
+
+ n_('Hello' \
+ 'Multiline %{name}', 'Hellos %{name}', 2) % { name: name }
+
+ var = "Hello"
+ n_(var, var, 1)
+ n_(method_name, method_name, count)
+ list.each { |item| n_(item, item, 2) }
+ n_(CONST, CONST, 2)
+ RUBY
+ end
+
+ it 'flags incorrect use' do
+ expect_offense(<<~'RUBY')
+ n_('Hello' + ' concat', 'Hellos', 2)
+ ^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `n_(...)`.
+ n_('Hello', 'Hello' + 's', 2)
+ ^^^^^^^^^^^^^ Ensure to pass static strings to translation method `n_(...)`.
+ n_("Hello #{name}", "Hellos", 2)
+ ^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `n_(...)`.
+ n_('Hello %{name}' % { name: name }, 'Hellos', 2)
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `n_(...)`.
+ n_('Hello' \
+ ^^^^^^^^^ Ensure to pass static strings to translation method `n_(...)`.
+ 'Multiline %{name}' % { name: name }, 'Hellos %{name}', 2)
+ n_('Hello', format('Hellos %{name}') % { name: name }, count)
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ensure to pass static strings to translation method `n_(...)`.
+ RUBY
+ end
+ end
+
+ describe 'edge cases' do
+ it 'does not flag' do
+ expect_no_offenses(<<~RUBY)
+ n_(s_('World|Hello'), s_('World|Hellos'), 2)
+ RUBY
+ end
+ end
+end