Sign in helper for a Devise project's rspec tests

sign_in_helper.rb

require 'rails_helper'
include Warden::Test::Helpers

module SignInHelper
  def sign_in_as_a_valid_user
    Warden.test_mode!
    user = FactoryGirl.create(:user)
    login_as(user, :scope => :user)
  end

  def sign_out
    Warden.test_reset!
  end
end