How do you create RoR Factory associations with accepts_nested_attributes_for?

Question

As Anton points out (thanks Anton!) my problem is Association Caching in the tests and it seems like I did correctly create the nested_attribute in the Factory. The correct syntax is:

Factory.define :job do |f|
  ...
  f.vehicles_attributes [{:vin => "1", :model => "ford", :make => "escort"},{:vin => "1", :model => "ford", :make => "escort" }]
end

---

I am using accepts_nested__attributes_for in my Job model and am trying to migrate to factory girl after nearly losing my marbles "fixture diving" every time I change the model.

I posted a bunch of code below but my question is straightforward:

How do I use factories to create nested_attributes?

I am able to create a Job instance using the code below but I cannot create create vehicles in my unit tests. Without the f.vehicles_attributes... my Job tests fail validations.

My unit tests produce the following results:

  test "factory" do
    job = Factory(:job)
    assert(job.valid?)  # => true
    assert(job.vehicles.first.valid?) # => true
    vehicle = Factory(:vehicle)
    assert(vehicle.job.vehicles.size == 1) # => true
    assert_equal(vehicle.job.vehicles.first.vin, "2") # => FALSE.  <"1"> expected but was <"2">
  end

---

Factory.define :job do |f|
  ...
  f.vehicles_attributes [:vin => "1", :model => "ford", :make => "escort" ]
end

Factory.define :vehicle do |f|
  f.vin "2"
  f.model "ford"
  f.make "escort"
  f.association :job
end

---

class Job < ActiveRecord::Base
  has_many :vehicles, :dependent => :destroy
  validate :job_must_have_at_least_one_vehicle
  accepts_nested_attributes_for :vehicles, :allow_destroy => :true, :reject_if => proc { |vehicle_attributes| Job.insufficient_vehicle_input?(vehicle_attributes) }

  def job_must_have_at_least_one_vehicle
    errors.add(:vehicles, "need to be added") if self.vehicles.empty?
  end

  def self.insufficient_vehicle_input?(vehicle_attributes)
    vehicle_property_keys = vehicle_attributes.keys
    vehicle_property_keys.delete('_delete')
    vehicle_property_keys.delete('is_operational')
    vehicle_property_keys.delete('has_keys')
    vehicle_property_keys.each do |attribute_to_validate|
      if(!vehicle_attributes[attribute_to_validate].nil? && !vehicle_attributes[attribute_to_validate].empty?)
        return false
      end
    end
    return true
  end
end

Answer 1

It is all about association caching.

Here is how it works:
1. Factory(:vehicle) builds vehicle object and creates job record
2. After that, it fills vehicle.job_id and saves it

But vehicle.job is pointed out a job object from step 1.
So, all that you need is to reload job:

vehicle = Factory(:vehicle)
vehicle.job.reload.vehicles.size # => 2