Testing Job call on model

gistfile1.rb

# test
describe '#initialize_delayed_recharge_process' do
  subject { create :transport_service_recharge_batch }

  let(:calculation_job) do
    instance_double(RH::TransportRechargeBatchCalculationJob)
  end

  it 'calls DelayedJob#enqueue on RH::TransportRechargeBatchCalculationJob' do
    expect(RH::TransportRechargeBatchCalculationJob).to receive(:new).
      with(id: subject.id).and_return(calculation_job)

    expect(Delayed::Job).to receive(:enqueue).with(calculation_job)

    subject.initialize_delayed_recharge_process
  end
end

#model
def initialize_delayed_recharge_process
  Delayed::Job.enqueue RH::TransportRechargeBatchCalculationJob.new(id: id)
end