text: #!/usr/bin/env python3
  # Copyright (c) 2019 The Stakinglab Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  '''
  Covers the scenario of a valid PoS block with a valid coinstake transaction where the
  coinstake input prevout is double spent in one of the other transactions in the same block.
  '''
  
  from time import sleep
  
  from fake_stake.base_test import LABX_FakeStakeTest
  
  
  class PoSDoubleSpend(LABX_FakeStakeTest):
  
      def run_test(self):
          self.description = "Covers the scenario of a valid PoS block with a valid coinstake transaction where the coinstake input prevout is double spent in one of the other transactions in the same block."
          self.init_test()
          INITAL_MINED_BLOCKS = 300
          FORK_DEPTH = 30
          self.NUM_BLOCKS = 3
  
          # 1) Starting mining blocks
          self.log.info("Mining %d blocks.." % INITAL_MINED_BLOCKS)
          self.node.generate(INITAL_MINED_BLOCKS)
  
          # 2) Collect the possible prevouts
          self.log.info("Collecting all unspent coins which we generated from mining...")
          staking_utxo_list = self.node.listunspent()
  
          # 3) Spam Blocks on the main chain
          self.log.info("-- Main chain blocks first")
          self.test_spam("Main", staking_utxo_list, fDoubleSpend=True)
          sleep(2)
  
          # 4) Mine some block as buffer
          self.log.info("Mining %d more blocks..." % FORK_DEPTH)
          self.node.generate(FORK_DEPTH)
          sleep(2)
  
          # 5) Spam Blocks on a forked chain
          self.log.info("-- Forked chain blocks now")
          err_msgs = self.test_spam("Forked", staking_utxo_list, fRandomHeight=True, randomRange=FORK_DEPTH, fDoubleSpend=True)
  
          if not len(err_msgs) == 0:
              self.log.error("result: " + " | ".join(err_msgs))
              raise AssertionError("TEST FAILED")
  
          self.log.info("%s PASSED" % self.__class__.__name__)
  
  if __name__ == '__main__':
      PoSDoubleSpend().main()
  