How would you test observers with rSpec in a Ruby on Rails application?

Question

Suppose you have an ActiveRecord::Observer in one of your Ruby on Rails applications - how do you test this observer with rSpec?

Answer 1

If you want to test that the observer observes the correct model and receives the notification as expected, here is an example using RR.

your_model.rb:

class YourModel < ActiveRecord::Base
    ...
end

your_model_observer.rb:

class YourModelObserver < ActiveRecord::Observer
    def after_create
        ...
    end

    def custom_notification
        ...
    end
end

your_model_observer_spec.rb:

before do
    @observer = YourModelObserver.instance
    @model = YourModel.new
end

it "acts on the after_create notification"
    mock(@observer).after_create(@model)
    @model.save!
end

it "acts on the custom notification"
    mock(@observer).custom_notification(@model)
    @model.send(:notify, :custom_notification)
end