cheat sheets.

CONTROLLERS

  assert_response :success  # 200
                  :redirect # 300-399
                  :missing  # 404
                  :error    # 500-599

MAILERS

  ActionMailer::Base.deliveries.clear

  email = ActionMailer::Base.deliveries[0]

  assert_equal email.from, "me@example.com"
  assert_equal email.to[0], 'friend@example.com'
  assert_equal email.subject, "You have been invited by me@example.com"
  assert_match /Hi friend@example.com/, email.body