RSpec / FactoryGirl - Rails STI - Equality

Simplified example:

I recently installed Single Table Inheritance

in a model Animal

. Cat

and Dog

are subclasses Animal

.

I have a Animal

factory: factory :animal do type { ["Dog","Cat"] }.sample end

Almost everywhere in my test suite, I call let(:animal) { Factory.create(:animal) }

because the type Animal

is irrelevant to the test. Since I switched to STI, I get errors when I do equality checks on these animals, because the superclass is Animal

returned by a factory, but when the related objects are instantiated Animal

, they return the subclass.

Example: expect(zoo.animal).to eq(animal)

fails: expected: #<Cat:0x007fa01a8cd360 same_other_attributes...> actual: #<Animal:0x007fa01b8d33b8 same_other_attributes...>

Is there a way to change the Animal

factory to return an instance of its subclass?

I tried to call .reload

in Animal

after the establishment of factory, but did not initiate the restart of a new (sub) class. I know you can usually call superclass.becomes!(subclass)

to force the change, but don't know how to put it in the callback FactoryGirl

in a way that will actually return the converted object.