Add `# frozen_string_literal: true`

app/models/prometheus_metric.rb

+# frozen_string_literal: true
+
 class PrometheusMetric < ActiveRecord::Base
   belongs_to :project, validate: true, inverse_of: :prometheus_metrics
 

db/fixtures/development/99_common_metrics.rb

+# frozen_string_literal: true
+
 require_relative '../importers/common_metrics_importer.rb'
 
 ::Importers::CommonMetricsImporter.new.execute

db/fixtures/production/999_common_metrics.rb

+# frozen_string_literal: true
+
 require_relative '../importers/common_metrics_importer.rb'
 
 ::Importers::CommonMetricsImporter.new.execute

db/migrate/20180101160629_create_prometheus_metrics.rb

+# frozen_string_literal: true
+
 class CreatePrometheusMetrics < ActiveRecord::Migration
   DOWNTIME = false
 

db/migrate/20180831164905_add_common_to_prometheus_metrics.rb

+# frozen_string_literal: true
+
 class AddCommonToPrometheusMetrics < ActiveRecord::Migration
   include Gitlab::Database::MigrationHelpers
 

db/migrate/20180831164906_change_project_id_for_prometheus_metrics.rb

+# frozen_string_literal: true
+
 class ChangeProjectIdForPrometheusMetrics < ActiveRecord::Migration
   include Gitlab::Database::MigrationHelpers
 

db/migrate/20180831164907_add_index_on_default_prometheus_metrics.rb → db/migrate/20180831164907_add_index_on_common_for_prometheus_metrics.rb

-class AddIndexOnDefaultPrometheusMetrics < ActiveRecord::Migration
+# frozen_string_literal: true
+
+class AddIndexOnCommonForPrometheusMetrics < ActiveRecord::Migration
   include Gitlab::Database::MigrationHelpers
 
   DOWNTIME = false

db/migrate/20180831164909_import_common_metrics.rb

+# frozen_string_literal: true
+
 class ImportCommonMetrics < ActiveRecord::Migration
   include Gitlab::Database::MigrationHelpers
 

spec/db/importers/common_metrics_importer_spec.rb

+# frozen_string_literal: true
+
 require 'rails_helper'
 require Rails.root.join("db", "importers", "common_metrics_importer.rb")
 

spec/factories/prometheus_metrics.rb

+# frozen_string_literal: true
+
 FactoryBot.define do
   factory :prometheus_metric, class: PrometheusMetric do
     title 'title'

spec/lib/gitlab/prometheus/metric_group_spec.rb

+# frozen_string_literal: true
+
 require 'rails_helper'
 
 describe Gitlab::Prometheus::MetricGroup do

spec/migrations/import_common_metrics_spec.rb

+# frozen_string_literal: true
+
 require 'spec_helper'
 require Rails.root.join('db', 'migrate', '20180831164909_import_common_metrics.rb')
 

spec/models/prometheus_metric_spec.rb

+# frozen_string_literal: true
+
 require 'spec_helper'
 
 describe PrometheusMetric do