title: Rails / RSpec: How to test #initialize method?
body: <p>How can I specify <code>#initialize</code> behaviour with RSpec? For example here:</p>
  
  <p><strong>generator.rb</strong></p>
  
  <pre><code>class Generator
    attr_accessor :seed
  
    def initialize(seed = nil)
      @seed = seed || pick_seed
    end
  
    def pick_seed
      Time.now.to_i
    end
  end
  </code></pre>
  
  <p><strong>generator_spec.rb</strong></p>
  
  <pre><code>require 'generator'
  
  describe Generator
  
    it "calls 'pick_seed' method unless seed specified" do
    end
  
  end
  </code></pre>
  
  <p>I'd like to set expectation that <code>pick_seed</code> method called from <code>#initialize</code> method.</p>