title: RSpec - mock (or stub) overriden mixin method
body: <p>I have situaltion like this:</p>
  
  <pre><code>module Something
    def my_method
      return :some_symbol
    end
  end
  
  class MyClass
    include Something
  
    def my_method
      if xxx?
        :other_symbol
      else
        super
      end
    end
  end
  </code></pre>
  
  <p>Now the problem is with testing - I would like to ensure that super method got called from overriden method and stub it so that I can test other parts of method. How can I accomplish that using RSpec mocks?</p>