RR Mock method called, but spec still fails

Question

Stack: Rails 3.0.7, Mongoid 2.2.5, RSpec 2.11.0, RR 1.0.4

I have a Subscription model that looks like this:

class Subscription
  include Mongoid::Document

  embeds_many :addons

  after_save :update_feature_policy!

  def update_feature_policy!
    puts "Updating feature policy!"
  end
end

I have a spec that looks like this:

it "should update FeaturePolicy when adding an addon" do
  puts "Starting spec"
  mock(subscription).update_feature_policy! { true }
  subscription.addons << user_addon
  puts "Finished spec"
end

The spec fails, but I see this output in the console:

Starting spec
Updating feature policy!
Finished spec

Failure/Error: mock(subscription).update_feature_policy! { true }
 RR::Errors::TimesCalledError:
   update_feature_policy!()
   Called 0 times.
   Expected 1 times.

What's causing the mock object not to capture the method call and pass the spec?

Answer 1

It appears that the callback was re-finding the record and creating a separate instance of subscription (thus not hitting the mock object). I'm not sure why - seems like it's not very performant - but I found a workaround:

it "should update FeaturePolicy when adding an addon" do
  puts "Starting spec"
  mock.instance_of(Subscription).update_feature_policy! { true }
  subscription.addons << user_addon
  puts "Finished spec"
end

This checks for update_feature_policy! being called on any instance of Subscription. Not great, but for my purposes it works.

If anyone can answer why this is happening or provide a better solution, please do.