shared_examples 'client acks are supported' do
  describe '#supports_client_acks' do
    it 'returns true' do
      expect(subject.supports_client_acks?).to eq(true)
    end
  end

  it { should respond_to :ack_message }
  it { should respond_to :nack_message }
end

shared_examples 'client acks are not supported' do
  describe '#supports_client_acks' do
    it 'returns false' do
      expect(subject.supports_client_acks?).to eq(false)
    end
  end
end