text: #!/usr/bin/env python2
  # Copyright (c) 2014-2019 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 proper accounting with malleable transactions
  #
  
  from test_framework import BitcoinTestFramework
  from bitcoinrpc.authproxy import AuthServiceProxy, JSONRPCException
  from decimal import Decimal
  from util import *
  import os
  import shutil
  
  class TxnMallTest(BitcoinTestFramework):
  
      def add_options(self, parser):
          parser.add_option("--mineblock", dest="mine_block", default=False, action="store_true",
                            help="Test double-spend of 1-confirmed transaction")
  
      def setup_network(self):
          # Start with split network:
          return super(TxnMallTest, self).setup_network(True)
  
      def run_test(self):
          # All nodes should start with 1,250 BTC:
          starting_balance = 6250
          for i in range(4):
              assert_equal(self.nodes[i].getbalance(), starting_balance)
              self.nodes[i].getnewaddress("")  # bug workaround, coins generated assigned to first getnewaddress!
          
          # Assign coins to foo and bar accounts:
          self.nodes[0].move("", "foo", 1220)
          self.nodes[0].move("", "bar", 30)
          assert_equal(self.nodes[0].getbalance(""), 0)
  
          # Coins are sent to node1_address
          node1_address = self.nodes[1].getnewaddress("from0")
  
          # First: use raw transaction API to send 1210 BTC to node1_address,
          # but don't broadcast:
          (total_in, inputs) = gather_inputs(self.nodes[0], 1210)
          change_address = self.nodes[0].getnewaddress("foo")
          outputs = {}
          outputs[change_address] = 40
          outputs[node1_address] = 1210
          rawtx = self.nodes[0].createrawtransaction(inputs, outputs)
          doublespend = self.nodes[0].signrawtransaction(rawtx)
          assert_equal(doublespend["complete"], True)
  
          # Create two transaction from node[0] to node[1]; the
          # second must spend change from the first because the first
          # spends all mature inputs:
          txid1 = self.nodes[0].sendfrom("foo", node1_address, 1210, 0)
          txid2 = self.nodes[0].sendfrom("bar", node1_address, 20, 0)
          
          # Have node0 mine a block:
          if (self.options.mine_block):
              self.nodes[0].setgenerate(True, 1)
              sync_blocks(self.nodes[0:2])
  
          tx1 = self.nodes[0].gettransaction(txid1)
          tx2 = self.nodes[0].gettransaction(txid2)
  
          # Node0's balance should be starting balance, plus 50BTC for another
          # matured block, minus 1210, minus 20, and minus transaction fees:
          expected = starting_balance
          if self.options.mine_block: expected += 50
          expected += tx1["amount"] + tx1["fee"]
          expected += tx2["amount"] + tx2["fee"]
          assert_equal(self.nodes[0].getbalance(), expected)
  
          # foo and bar accounts should be debited:
          assert_equal(self.nodes[0].getbalance("foo"), 1220+tx1["amount"]+tx1["fee"])
          assert_equal(self.nodes[0].getbalance("bar"), 30+tx2["amount"]+tx2["fee"])
  
          if self.options.mine_block:
              assert_equal(tx1["confirmations"], 1)
              assert_equal(tx2["confirmations"], 1)
              # Node1's "from0" balance should be both transaction amounts:
              assert_equal(self.nodes[1].getbalance("from0"), -(tx1["amount"]+tx2["amount"]))
          else:
              assert_equal(tx1["confirmations"], 0)
              assert_equal(tx2["confirmations"], 0)
          
          # Now give doublespend to miner:
          mutated_txid = self.nodes[2].sendrawtransaction(doublespend["hex"])
          # ... mine a block...
          self.nodes[2].setgenerate(True, 1)
  
          # Reconnect the split network, and sync chain:
          connect_nodes(self.nodes[1], 2)
          self.nodes[2].setgenerate(True, 1)  # Mine another block to make sure we sync
          sync_blocks(self.nodes)
  
          # Re-fetch transaction info:
          tx1 = self.nodes[0].gettransaction(txid1)
          tx2 = self.nodes[0].gettransaction(txid2)
          
          # Both transactions should be conflicted
          assert_equal(tx1["confirmations"], -1)
          assert_equal(tx2["confirmations"], -1)
  
          # Node0's total balance should be starting balance, plus 100BTC for 
          # two more matured blocks, minus 1210 for the double-spend:
          expected = starting_balance + 100 - 1210
          assert_equal(self.nodes[0].getbalance(), expected)
          assert_equal(self.nodes[0].getbalance("*"), expected)
  
          # foo account should be debited, but bar account should not:
          assert_equal(self.nodes[0].getbalance("foo"), 1220-1210)
          assert_equal(self.nodes[0].getbalance("bar"), 30)
  
          # Node1's "from" account balance should be just the mutated send:
          assert_equal(self.nodes[1].getbalance("from0"), 1210)
  
  if __name__ == '__main__':
      TxnMallTest().main()
  