ThingsController

class ThingsController < ApplicationController
  def index
    puts defined?(@something)
    puts @something
    @something = "test"
    render :text => 'done'
  end
end

ThingsControllerSpec

# expected output for each spec
# -----------------------------
# nil
# nil
# nil
# nil

describe ThingsController do
  describe "test" do
    # actual output
    # -------------
    # nil
    # nil
    # "instance-variable"
    # "already set"
    it "two requests" do
      get :index
      get :index
    end

    # actual output
    # -------------
    # nil
    # nil
    # "instance-variable"
    # "already set"
    it "another two requests" do
      get :index
      get :index
    end    
  end
end