bid_accepted_job.rb

class BidAcceptedJob < Struct.new(:bid_id)
  PRIORITY = 1

  def self.enqueue(bid)
    Delayed::Job.enqueue new(bid.id), priority: PRIORITY
  end

  def perform
    Mailer.bid_accepted(aide, bid).deliver
    Activity.create activity_type: 'bid_accepted', subject: bid, user: aide
    Activity.create activity_type: 'bid_accepted', subject: bid, user: owner
  end

  private

  def aide
    bid.user
  end

  def bid
    Bid.find bid_id
  end

  def owner
    bid.job.owner
  end
end

bid_accepted_job_spec.rb

  context 'self.enqueue' do
    before do
      @bid = build_stubbed(:bid)
      BidAcceptedJob.enqueue @bid
    end

    it do
      should enqueue_delayed_job('BidAcceptedJob').
        with_attributes(bid_id: @bid.id).
        priority(1)
    end
  end

delayed_job_matcher.rb

module DelayedJob
  module Matchers
    def enqueue_delayed_job(handler)
      DelayedJobMatcher.new handler
    end

    class DelayedJobMatcher
      def initialize(handler)
        @handler = handler
        @attributes = {}
        @priority = 0
        @failure_message = ''
      end

      def description
        "enqueue a #{@handler} delayed job"
      end

      def failure_message
        <<-message.strip_heredoc
          Expected #{@handler} to be enqueued as a delayed job. Try:
          Delayed::Job.enqueue #{@handler}.new
        message
      end

      def matches?(subject)
        @subject = subject
        enqueued? && correct_attributes? && correct_priority?
      end

      def priority(priority)
        @priority = priority
        self
      end

      def with_attributes(attributes)
        @attributes = attributes
        self
      end

      private

      def correct_attributes?
        @attributes.each do |key, value|
          payload_object.send(key).should == value
        end
      end

      def correct_priority?
        if @priority == job.priority
          true
        else
          @failure_message = <<-message.strip_heredoc
            Expected priority to be #{@priority} but was #{job.priority}"
          message

          false
        end
      end

      def enqueued?
        payload_object.kind_of? @handler.constantize
      end

      def job
        Delayed::Job.last
      end

      def payload_object
        job.payload_object
      end
    end
  end
end