old_contents: """Tests for letsencrypt.errors."""
  import unittest
  
  from acme import messages
  
  from letsencrypt import achallenges
  from letsencrypt.tests import acme_util
  
  
  class FaiiledChallengesTest(unittest.TestCase):
      """Tests for letsencrypt.errors.FailedChallenges."""
  
      def setUp(self):
          from letsencrypt.errors import FailedChallenges
          self.error = FailedChallenges(set([achallenges.DNS(
              domain="example.com", challb=messages.ChallengeBody(
                  chall=acme_util.DNS, uri=None,
                  error=messages.Error(typ="tls", detail="detail")))]))
  
      def test_str(self):
          self.assertTrue(str(self.error).startswith(
              "Failed authorization procedure. example.com (dns): tls"))
  
  
  if __name__ == "__main__":
      unittest.main()  # pragma: no cover
  
new_contents: """Tests for letsencrypt.errors."""
  import unittest
  
  import mock
  
  from acme import messages
  
  from letsencrypt import achallenges
  from letsencrypt.tests import acme_util
  
  
  class FaiiledChallengesTest(unittest.TestCase):
      """Tests for letsencrypt.errors.FailedChallenges."""
  
      def setUp(self):
          from letsencrypt.errors import FailedChallenges
          self.error = FailedChallenges(set([achallenges.DNS(
              domain="example.com", challb=messages.ChallengeBody(
                  chall=acme_util.DNS, uri=None,
                  error=messages.Error(typ="tls", detail="detail")))]))
  
      def test_str(self):
          self.assertTrue(str(self.error).startswith(
              "Failed authorization procedure. example.com (dns): tls"))
  
  
  class StandaloneBindErrorTest(unittest.TestCase):
      """Tests for letsencrypt.errors.StandaloneBindError."""
  
      def setUp(self):
          from letsencrypt.errors import StandaloneBindError
          self.error = StandaloneBindError(mock.sentinel.error, 1234)
  
      def test_instance_args(self):
          self.assertEqual(mock.sentinel.error, self.error.socket_error)
          self.assertEqual(1234, self.error.port)
  
      def test_str(self):
          self.assertTrue(str(self.error).startswith(
              "Problem binding to port 1234: "))
  
  
  if __name__ == "__main__":
      unittest.main()  # pragma: no cover
  
subject: Add StandaloneBindErrorTest