How to get coverage when using rescue, and retry using stubs not VCR, in Rspec 3.5?

Question

I am trying to get coverage on the following sections of code in my attached spec. This project prefers to use stubs over VCR and external API requests are blocked. Does anyone have any ideas on how to approach this issue to get the coverage needed?

I have the sleep test commented out because it is failing.

Code

  def first_page
    client.list_orders(created_before: created_before,
                       created_after: created_after,
                       max_results_per_page: max_results_per_page)
  rescue Excon::Error::ServiceUnavailable => error
    log_error(error, 'amazon_mws.errors.orders.first_page') unless (self.retries -= 1).positive?
    add_api_delay
    retry
  end

  def next_page(next_token)
    client.list_orders_by_next_token(next_token)
  rescue Excon::Error::ServiceUnavailable => error
    log_error(error, 'amazon_mws.errors.orders.next_page') unless (self.retries -= 1).positive?
    add_api_delay
    retry
  end

  def add_api_delay
    sleep(Configurations.amazon_mws['orders']['response_timer_in_seconds'])
  end

Spec

  describe '.poll_for_order_items' do
    context 'multiple pages' do
      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_return(body: next_page, status: 200, headers: { 'Content-Type': 'text/xml' })

        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItemsByNextToken&).*$/)
          .to_return(body: first_page, status: 200, headers: { 'Content-Type': 'text/xml' })
      end

      context 'with sleep stubbed' do
        before do
          allow(subject).to receive(:add_api_delay).and_return(true)
        end

        it 'returns array collection' do
          expect(subject.poll_for_order_items).to be_kind_of(Array)
        end

        it 'returns array data' do
          expect(subject.poll_for_order_items.length).to be > 0
        end
      end

      # context 'with sleep set' do
      #   it 'should call sleep' do
      #     allow(Kernel).to receive(:sleep).and_return(1)
      #     expect(subject).to receive(:sleep).and_return(1)
      #     subject.poll_for_order_items
      #   end
      # end
    end

    context 'single page' do
      before(:each) do
        stub_request(:any, /.*amazonservices.com.*/).to_return(body: first_page, status: 200, headers: { 'Content-Type': 'text/xml' })
        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'returns array' do
        expect(subject.poll_for_order_items).to be_kind_of(Array)
      end

      it 'returns array data' do
        expect(subject.poll_for_order_items.length).to be > 0
      end
    end

    context 'collector' do
      before(:each) do
        stub_request(:any, /.*amazonservices.com.*/).to_return(body: first_page_single, status: 200, headers: { 'Content-Type': 'text/xml' })
        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'returns array when non array returned' do
        expect(subject.poll_for_order_items).to be_kind_of(Array)
      end
    end
  end

  describe 'raises errors' do
    context '.parse' do
      let(:error_raised) { I18n.t('amazon_mws.errors.parse_payload') }

      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_return(body: {}.to_json, status: 200, headers: { 'Content-Type': 'text/xml' })
      end

      it 'raises error' do
        expect { subject.new } .to raise_error(StandardError)
      end
    end

    context '.first_page' do
      let(:error_raised) { I18n.t('amazon_mws.errors.order_items.first_page') }

      before do
        allow(MWS).to receive_message_chain(:orders, :list_order_items).and_raise(error_raised)
      end

      it 'raises error on first listing page' do
        expect { subject.new } .to raise_error(StandardError)
      end
    end

    context '.next_page' do
      let(:error_raised) { I18n.t('amazon_mws.errors.order_items.next_page') }

      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_return(body: next_page, status: 200, headers: { 'Content-Type': 'text/xml' })

        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItemsByNextToken&).*$/)
          .and_raise(error_raised)

        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'raises error on nexst listing page' do
        expect { subject.poll_for_order_items } .to raise_error(StandardError)
      end
    end
  end

Coverage Report

Answer 1

I only see that you're expecting it to raise the error. If it's timing out then it should call log_error and add_api_delay at least once. Since those are basically side effects you might just need to test they they get called in that circumstance and the coverage report should know about it.

Try adding expectations like: expect(subject).to have_received(:log_error).at_least(:once)

EDIT: Talking about it out-of-band and we learned most of the coverage problem could be solved by making sure the error is being raised.

before do stub_request(:any, /.*amazonservices.com.*/) .with(body: /^.*(&Action=ListOrders&).*$/) .to_raise(Excon::Error::ServiceUnavailable) end

Answer 2

After research and inspiration from @wobh above I came up with the following...

  describe '.poll_for_order_items' do
    context 'multiple pages' do
      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_return(body: next_page, status: 200, headers: { 'Content-Type': 'text/xml' })

        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItemsByNextToken&).*$/)
          .to_return(body: first_page, status: 200, headers: { 'Content-Type': 'text/xml' })
      end

      context 'with sleep stubbed' do
        before do
          allow(subject).to receive(:add_api_delay).and_return(true)
        end

        it 'returns array collection' do
          expect(subject.poll_for_order_items).to be_kind_of(Array)
        end

        it 'returns array data' do
          expect(subject.poll_for_order_items.length).to be > 0
        end
      end
    end

    context 'single page' do
      before(:each) do
        stub_request(:any, /.*amazonservices.com.*/).to_return(body: first_page, status: 200, headers: { 'Content-Type': 'text/xml' })
        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'returns array' do
        expect(subject.poll_for_order_items).to be_kind_of(Array)
      end

      it 'returns array data' do
        expect(subject.poll_for_order_items.length).to be > 0
      end
    end

    context 'collector' do
      before(:each) do
        stub_request(:any, /.*amazonservices.com.*/).to_return(body: first_page_single, status: 200, headers: { 'Content-Type': 'text/xml' })
        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'returns array when non array returned' do
        expect(subject.poll_for_order_items).to be_kind_of(Array)
      end
    end
  end

  describe 'raises errors' do
    context '.parse' do
      let(:error_raised) { I18n.t('amazon_mws.errors.parse_payload', error: 'TEST') }

      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_return(body: {}.to_json, status: 200, headers: { 'Content-Type': 'text/xml' })
      end

      it 'raises error' do
        expect { subject.poll_for_order_items } .to raise_error(StandardError)
      end

      it 'raises correct error message' do
        expect { subject.poll_for_order_items } .to raise_error(/payload/)
      end
    end

    context '.first_page' do
      let(:error_raised) { I18n.t('amazon_mws.errors.order_items.first_page', error: 'TEST') }

      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_raise(Excon::Error::ServiceUnavailable)
        subject.instance_variable_set(:@retry_limit, 1)
        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'raises error on first listing page' do
        expect { subject.poll_for_order_items } .to raise_error(StandardError)
      end

      it 'raises correct error message' do
        expect { subject.poll_for_order_items } .to raise_error(/order item first/)
      end
    end

    context '.next_page' do
      let(:error_raised) { I18n.t('amazon_mws.errors.order_items.next_page', error: 'TEST') }

      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_return(body: next_page, status: 200, headers: { 'Content-Type': 'text/xml' })

        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItemsByNextToken&).*$/)
          .to_raise(Excon::Error::ServiceUnavailable)
        subject.instance_variable_set(:@retry_limit, 1)
        allow(subject).to receive(:add_api_delay).and_return(true)
      end

      it 'raises error on next listing page' do
        expect { subject.poll_for_order_items } .to raise_error(StandardError)
      end

      it 'raises correct error message' do
        expect { subject.poll_for_order_items } .to raise_error(/order item next/)
      end
    end

    context '.add_api_delay' do
      before do
        stub_request(:any, /.*amazonservices.com.*/)
          .with(body: /^.*(&Action=ListOrderItems&).*$/)
          .to_raise(Excon::Error::ServiceUnavailable)

        subject.instance_variable_set(:@retries, 2)
        subject.instance_variable_set(:@retry_limit, 1)
        subject.instance_variable_set(:@retry_delay, 1)
      end

      it 'sleeps retry api calls' do
        allow(Kernel).to receive(:sleep).and_return(1)
        expect(subject).to receive(:sleep).and_return(1)
        expect { subject.poll_for_order_items } .to raise_error(StandardError)
      end
    end
  end

THIS RESULTED IN 100% COVERAGE!