```ruby
require 'spec_helper'

if defined?(::Sidekiq)
  require 'sidekiq/testing'

  describe Chewy::Strategy::Sidekiq do
    around { |example| Chewy.strategy(:bypass) { example.run } }
    before { ::Sidekiq::Worker.clear_all }
    before do
      stub_model(:city) do
        update_index('cities#city') { self }
      end

      stub_index(:cities) do
        define_type City
      end
    end

    let(:city) { City.create!(name: 'hello') }
    let(:other_city) { City.create!(name: 'world') }

    specify do
      expect { [city, other_city].map(&:save!) }
        .not_to update_index(CitiesIndex::City, strategy: :sidekiq)
    end

    specify do
      ::Sidekiq::Testing.inline! do
        expect { [city, other_city].map(&:save!) }
          .to update_index(CitiesIndex::City, strategy: :sidekiq)
          .and_reindex(city, other_city).only
      end
    end

    specify do
      expect(CitiesIndex::City).to receive(:import!).with([city.id, other_city.id], suffix: '201601')
      Chewy::Strategy::Sidekiq::Worker.new.perform('CitiesIndex::City', [city.id, other_city.id], suffix: '201601')
    end
  end
end
```

Add small spec piece for sidekiq queue
user
```ruby
require 'spec_helper'

if defined?(::Sidekiq)
  require 'sidekiq/testing'

  describe Chewy::Strategy::Sidekiq do
    around { |example| Chewy.strategy(:bypass) { example.run } }
    before { ::Sidekiq::Worker.clear_all }
    before do
      stub_model(:city) do
        update_index('cities#city') { self }
      end

      stub_index(:cities) do
        define_type City
      end
    end

    let(:city) { City.create!(name: 'hello') }
    let(:other_city) { City.create!(name: 'world') }

    specify do
      expect { [city, other_city].map(&:save!) }
        .not_to update_index(CitiesIndex::City, strategy: :sidekiq)
    end

    specify do
      Chewy.settings[:sidekiq] = { queue: 'low' }
      expect(::Sidekiq::Client).to receive(:push).with(hash_including('queue' => 'low')).and_call_original
      ::Sidekiq::Testing.inline! do
        expect { [city, other_city].map(&:save!) }
          .to update_index(CitiesIndex::City, strategy: :sidekiq)
          .and_reindex(city, other_city).only
      end
    end

    specify do
      expect(CitiesIndex::City).to receive(:import!).with([city.id, other_city.id], suffix: '201601')
      Chewy::Strategy::Sidekiq::Worker.new.perform('CitiesIndex::City', [city.id, other_city.id], suffix: '201601')
    end
  end
end
```
assistant