old_contents: #!/usr/bin/env python3
  # Copyright (c) 2014-2016 The Bitcoin Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  """Test the -alertnotify option."""
  import os
  import time
  
  from test_framework.test_framework import BitcoinTestFramework
  
  class ForkNotifyTest(BitcoinTestFramework):
      def set_test_params(self):
          self.num_nodes = 2
  
      def setup_network(self):
          self.alert_filename = os.path.join(self.options.tmpdir, "alert.txt")
          with open(self.alert_filename, 'w', encoding='utf8'):
              pass  # Just open then close to create zero-length file
          self.extra_args = [["-blockversion=2", "-alertnotify=echo %s >> \"" + self.alert_filename + "\""],
                             ["-blockversion=211"]]
          super().setup_network()
  
      def run_test(self):
          # Mine 51 up-version blocks
          self.nodes[1].generate(51)
          self.sync_all()
          # -alertnotify should trigger on the 51'st,
          # but mine and sync another to give
          # -alertnotify time to write
          self.nodes[1].generate(1)
          self.sync_all()
  
          # Give bitcoind 10 seconds to write the alert notification
          timeout = 10.0
          while timeout > 0:
              if os.path.exists(self.alert_filename) and os.path.getsize(self.alert_filename):
                  break
              time.sleep(0.1)
              timeout -= 0.1
          else:
              assert False, "-alertnotify did not warn of up-version blocks"
  
          with open(self.alert_filename, 'r', encoding='utf8') as f:
              alert_text = f.read()
  
          # Mine more up-version blocks, should not get more alerts:
          self.nodes[1].generate(1)
          self.sync_all()
          self.nodes[1].generate(1)
          self.sync_all()
  
          with open(self.alert_filename, 'r', encoding='utf8') as f:
              alert_text2 = f.read()
  
          if alert_text != alert_text2:
              raise AssertionError("-alertnotify excessive warning of up-version blocks")
  
  if __name__ == '__main__':
      ForkNotifyTest().main()
  
new_contents: #!/usr/bin/env python3
  # Copyright (c) 2014-2016 The Bitcoin Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  """Test the -alertnotify option."""
  import os
  
  from test_framework.test_framework import BitcoinTestFramework
  from test_framework.util import assert_equal, wait_until
  
  class ForkNotifyTest(BitcoinTestFramework):
      def set_test_params(self):
          self.num_nodes = 2
  
      def setup_network(self):
          self.alert_filename = os.path.join(self.options.tmpdir, "alert.txt")
          self.extra_args = [["-alertnotify=echo %%s >> %s" % self.alert_filename],
                             ["-blockversion=211"]]
          super().setup_network()
  
      def run_test(self):
          # Mine 51 up-version blocks. -alertnotify should trigger on the 51st.
          self.nodes[1].generate(51)
          self.sync_all()
  
          # Give bitcoind 10 seconds to write the alert notification
          wait_until(lambda: os.path.isfile(self.alert_filename) and os.path.getsize(self.alert_filename), timeout=10)
  
          with open(self.alert_filename, 'r', encoding='utf8') as f:
              alert_text = f.read()
  
          # Mine more up-version blocks, should not get more alerts:
          self.nodes[1].generate(2)
          self.sync_all()
  
          with open(self.alert_filename, 'r', encoding='utf8') as f:
              alert_text2 = f.read()
  
          self.log.info("-alertnotify should not continue notifying for more unknown version blocks")
          assert_equal(alert_text, alert_text2)
  
  if __name__ == '__main__':
      ForkNotifyTest().main()
  
subject: Tidy up forknotify.py