builders_profile_page_spec.rb

require "spec_helper"
require "./app/builders/profile_page"

describe Builders::ProfilePage do
  describe "#build" do
   it "builds a new instance of Participant::ProfilePage" do
     stub_requests
     profile_page = spy_on_class("Participant::ProfilePage")
     builder = create_builder

     builder.build

     expect(profile_page).to have_received(:new)
       .with(project: builder.project,
             participant: builder.participant,
             tasks: builder.tasks,
             latest_photos: builder.latest_photos)
   end
  end

  describe "#project" do
    it "fetches the desired Project and wraps it with a ProjectDecorator" do
      project_id = 1
      project_decorator = spy_on_class("ProjectDecorator")

      create_builder(project_id: project_id).project

      expect(project_decorator).to have_received(:find).with(project_id)
    end
  end

  describe "#participant" do
    it "fetches the desired Participant and wraps it with a Participant::ProfileDecorator" do
      options = { project_id: 1, participant_id: 2 }
      profile_decorator = spy_on_class("Participant::ProfileDecorator")
      project_participant = spy_on_class("Participant::ProjectParticipant")

      create_builder(options).participant

      expect(profile_decorator).to have_received(:new)
      expect(project_participant).to have_received(:find_within_project)
        .with(options)
    end
  end

  describe "#tasks" do
    it "wraps each Task of the Project with a Participant::TaskDecorator" do
      project = instance_double("Project", tasks: [])
      allow(ProjectDecorator).to receive(:find).and_return(project)
      task_decorator = spy_on_class("Participant::TaskDecorator")

      create_builder.tasks

      expect(task_decorator).to have_received(:decorate_collection)
    end
  end

  describe "#latest_photos" do
    it "is a list of the latest photos a Participant has uploaded" do
      options = { project_id: 1, participant_id: 2 }
      photos = instance_spy("Participant::LatestPhotos")
      allow(Participant::LatestPhotos).to receive(:new).and_return(photos)

      create_builder(options).latest_photos

      expect(Participant::LatestPhotos).to have_received(:new).with(options)
      expect(photos).to have_received(:call)
    end
  end

  # class_spy doesn’t override the constant automatically, it requires you to
  # add .as_stubbed_const to override the constant
  def spy_on_class(klass)
    class_spy(klass).as_stubbed_const
  end

  def stub_requests
  # ...
  end

  def create_builder(project_id: 1, participant_id: 2)
    Builders::ProfilePage.new(project_id: project_id,
                              participant_id: participant_id)
  end
end

buillders_profile_page.rb

require "project_decorator"
require "participant/profile_decorator"
require "participant/task_decorator"
require "participant/profile_page"

module Builders
  class ProfilePage
    def initialize(project_id:, participant_id:)
      @project_id = project_id
      @participant_id = participant_id
    end

    def build
      Participant::ProfilePage.new(project: project,
                                   participant: participant,
                                   tasks: tasks,
                                   latest_photos: latest_photos)
    end

    def project
      ProjectDecorator.find(project_id)
    end

    def participant
      Participant::ProfileDecorator.new(find_participant)
    end

    def tasks
      Participant::TaskDecorator.decorate_collection(project.tasks)
    end

    def latest_photos
      Participant::LatestPhotos.new(project_id: project_id,
                                    participant_id: participant_id).call
    end

    private

    attr_reader :project_id, :participant_id

    def find_participant
      Participant::ProjectParticipant.find_within_project(
        project_id: project_id, participant_id: participant_id
      )
    end
  end
end

profile_page.rb

module Participant
  # Extracts the concerns of the Participant Profile page
  class ProfilePage
    def initialize(project:, participant:, tasks:, latest_photos:)
      @project = project
      @participant = participant
      @tasks = tasks
      @latest_photos = latest_photos
    end

    attr_reader :project, :participant, :tasks, :latest_photos
  end
end