How to test model's callback method independently?

Question

I had a method in a model:

class Article < ActiveRecord::Base
  def do_something
  end
end

I also had a unit test for this method:

Answer 1

describe "#do_something" do

 it "gives the article something" do

  @article = FactoryGirl.build(:article)

   expect(@article).to have_something

 @article.save
end

end