old_contents: """Tests for acme.errors."""
  import unittest
  
  import mock
  
  
  class BadNonceTest(unittest.TestCase):
      """Tests for acme.errors.BadNonce."""
  
      def setUp(self):
          from acme.errors import BadNonce
          self.error = BadNonce(nonce="xxx", error="error")
  
      def test_str(self):
          self.assertEqual("Invalid nonce ('xxx'): error", str(self.error))
  
  
  class MissingNonceTest(unittest.TestCase):
      """Tests for acme.errors.MissingNonce."""
  
      def setUp(self):
          from acme.errors import MissingNonce
          self.response = mock.MagicMock(headers={})
          self.response.request.method = 'FOO'
          self.error = MissingNonce(self.response)
  
      def test_str(self):
          self.assertTrue("FOO" in str(self.error))
          self.assertTrue("{}" in str(self.error))
  
  
  class PollErrorTest(unittest.TestCase):
      """Tests for acme.errors.PollError."""
  
      def setUp(self):
          from acme.errors import PollError
          self.timeout = PollError(
              exhausted=set([mock.sentinel.AR]),
              updated={})
          self.invalid = PollError(exhausted=set(), updated={
              mock.sentinel.AR: mock.sentinel.AR2})
  
      def test_timeout(self):
          self.assertTrue(self.timeout.timeout)
          self.assertFalse(self.invalid.timeout)
  
      def test_repr(self):
          self.assertEqual('PollError(exhausted=set([]), updated={sentinel.AR: '
                           'sentinel.AR2})', repr(self.invalid))
  
  
  if __name__ == "__main__":
      unittest.main()  # pragma: no cover
  
new_contents: """Tests for acme.errors."""
  import unittest
  
  import mock
  
  
  class BadNonceTest(unittest.TestCase):
      """Tests for acme.errors.BadNonce."""
  
      def setUp(self):
          from acme.errors import BadNonce
          self.error = BadNonce(nonce="xxx", error="error")
  
      def test_str(self):
          self.assertEqual("Invalid nonce ('xxx'): error", str(self.error))
  
  
  class MissingNonceTest(unittest.TestCase):
      """Tests for acme.errors.MissingNonce."""
  
      def setUp(self):
          from acme.errors import MissingNonce
          self.response = mock.MagicMock(headers={})
          self.response.request.method = 'FOO'
          self.error = MissingNonce(self.response)
  
      def test_str(self):
          self.assertTrue("FOO" in str(self.error))
          self.assertTrue("{}" in str(self.error))
  
  
  class PollErrorTest(unittest.TestCase):
      """Tests for acme.errors.PollError."""
  
      def setUp(self):
          from acme.errors import PollError
          self.timeout = PollError(
              exhausted=set([mock.sentinel.AR]),
              updated={})
          self.invalid = PollError(exhausted=set(), updated={
              mock.sentinel.AR: mock.sentinel.AR2})
  
      def test_timeout(self):
          self.assertTrue(self.timeout.timeout)
          self.assertFalse(self.invalid.timeout)
  
      def test_repr(self):
          self.assertEqual('PollError(exhausted=%s, updated={sentinel.AR: '
                           'sentinel.AR2})' % repr(set()), repr(self.invalid))
  
  
  if __name__ == "__main__":
      unittest.main()  # pragma: no cover
  
subject: fix empty set repr py3 compat