factories.rb

# How to properly handle circular references with factory_girl and rails

class Computer < ActiveRecord::Base
  has_many :softwares
end

class Software < ActiveRecord::Base
  belongs_to :computer
end

Factory.define :computer do |c|
  c.softwares do |computer|
    5.times.map { computer.association(:software, :computer => nil) }
  end
end

Factory.define :software do |s|
  s.association :computer
  s.name "XMonad"
end