Make sessions work in Rack::Test with Sinatra's sessions

gistfile1.rb

# Put this in your test helper file
# This works when using the default Sinatra sessions (i.e. enable :sessions)

# (helper preamble not included)
require 'securerandom'
class Test::Unit::TestCase
  include Rack::Test::Methods

  def app
    Sinatra::Application # or the name of your modular app
  end

  def setup_session(data = {})
    sid = SecureRandom.hex(32)
    hsh = data.merge("session_id" => sid)
    data = [Marshal.dump(hsh)].pack('m')
    secret = app.session_secret
    hmac = OpenSSL::HMAC.hexdigest(OpenSSL::Digest::SHA1.new, secret, data)
    str = "#{data}--#{hmac}"
    set_cookie("rack.session=#{URI.encode_www_form_component(str)}")
  end
end