old_contents: from unittest import TestCase
  
  from keteparaha.browser import BrowserTestCase
  
  
  class BrowserTestCaseTest(TestCase):
  
      class SubClassed(BrowserTestCase):
  
          def do_nothing(self):
              pass
  
      def test_start_browser_when_given_unsupported_driver(self):
          bc = self.SubClassed("do_nothing")
  
          with self.assertRaises(ValueError):
              bc.start_browser(driver="NoReal")
  
          self.assertEqual(bc._browsers, [])
  
      def test_browser_is_cleaned_up_afterwards(self):
          bc = self.SubClassed("do_nothing")
          bc.start_browser("Firefox")
  
          bc.doCleanups()
  
          with self.assertRaises(Exception):
              bc.title
  
new_contents: from unittest import TestCase
  
  from keteparaha.browser import BrowserTestCase
  
  
  class SubClassed(BrowserTestCase):
  
      def do_nothing(self):
          pass
  
  
  class BrowserTestCaseTest(TestCase):
  
  
  
      def test_browser_returns_last_browser_started(self):
  
          btc = SubClassed('do_nothing')
  
          btc.browsers.append('b1')
          btc.browsers.append('b2')
          btc.browsers.append('b3')
  
          self.assertEqual(btc.browser, 'b3')
  
  
subject: Modify tests for the BrowserTestCase class so they don't hang