rspec testing has_many :through association

spec_has_many_through.rb

# video.rb
class Video < ActiveRecord::Base
  has_many :categorizations
  has_many :categories, through: :categorizations
end
 
# category.rb
class Category < ActiveRecord::Base
  has_many :categorizations
  has_many :videos, through: :categorizations
end
 
# categorization.rb
class Categorization < ActiveRecord::Base
  belongs_to :video
  belongs_to :category
end
 
# video_spec.rb
require 'spec_helper'
 
describe Video do
  it "have created a relationship with Category" do
    video = Video.create(title: "futurama", description: "fry, a pizza guy is accidentally frozen in 1999")
    category = Category.create(name: "comedies")
 
    video.categories << category
 
    Categorization.first.video.should == video
    Categorization.first.category.should == category
  end
 
  it "have categories" do
    video = Video.create(title: "futurama", description: "fry, a pizza guy is accidentally frozen in 1999")
    category = Category.create(name: "comedies")
 
    video.categories << category
 
    video.categories.should == [category]
  end
end