title: Rails 3 Capybara error
body: <p>I'm trying to get Capybara to work with rails 3 (and test unit) but when I try to run <code>rake test:integration</code> I get an error:<code>ArgumentError: @request must be an ActionDispatch::Request
  </code></p>
  
  <p><strong>The test</strong>:</p>
  
  <pre><code>require 'integration_test_helper'
  
  class UserNotesTest &lt; ActionDispatch::IntegrationTest
    test "User should login" do
      user = Factory.create(:user)
      visit '/login'
      assert_response :success
  
      fill_in 'user_email', :with =&gt; user.email
      fill_in 'user_password', :with =&gt; user.password
      click_button 'Sign in'
  
      assert_redirect_to notes_path
    end
  end
  </code></pre>
  
  <p><strong>integration_test_helper:</strong></p>
  
  <pre><code>require 'test_helper'
  require 'capybara/rails'
  
  module ActionDispatch
    class IntegrationTest
      include Capybara
    end
  end
  </code></pre>
  
  <p>I'm not really sure whats going wrong...</p>