text: #!/usr/bin/env python3
  # Copyright (c) 2014-2018 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 descendant package tracking code."""
  
  from decimal import Decimal
  
  from test_framework.messages import COIN
  from test_framework.test_framework import CONNEXTestFramework
  from test_framework.util import assert_equal, assert_raises_rpc_error, satoshi_round, sync_blocks, sync_mempools
  
  MAX_ANCESTORS = 25
  MAX_DESCENDANTS = 25
  
  class MempoolPackagesTest(CONNEXTestFramework):
      def set_test_params(self):
          self.num_nodes = 2
          self.extra_args = [["-maxorphantx=1000"], ["-maxorphantx=1000", "-limitancestorcount=5"]]
  
      # Build a transaction that spends parent_txid:vout
      # Return amount sent
      def chain_transaction(self, node, parent_txid, vout, value, fee, num_outputs):
          send_value = satoshi_round((value - fee)/num_outputs)
          inputs = [ {'txid' : parent_txid, 'vout' : vout} ]
          outputs = {}
          for i in range(num_outputs):
              outputs[node.getnewaddress()] = send_value
          rawtx = node.createrawtransaction(inputs, outputs)
          signedtx = node.signrawtransactionwithwallet(rawtx)
          txid = node.sendrawtransaction(signedtx['hex'])
          fulltx = node.getrawtransaction(txid, 1)
          assert(len(fulltx['vout']) == num_outputs) # make sure we didn't generate a change output
          return (txid, send_value)
  
      def run_test(self):
          ''' Mine some blocks and have them mature. '''
          self.nodes[0].generate(101)
          utxo = self.nodes[0].listunspent(10)
          txid = utxo[0]['txid']
          vout = utxo[0]['vout']
          value = utxo[0]['amount']
  
          fee = Decimal("0.0001")
          # MAX_ANCESTORS transactions off a confirmed tx should be fine
          chain = []
          for i in range(MAX_ANCESTORS):
              (txid, sent_value) = self.chain_transaction(self.nodes[0], txid, 0, value, fee, 1)
              value = sent_value
              chain.append(txid)
  
          # Check mempool has MAX_ANCESTORS transactions in it, and descendant and ancestor
          # count and fees should look correct
          mempool = self.nodes[0].getrawmempool(True)
          assert_equal(len(mempool), MAX_ANCESTORS)
          descendant_count = 1
          descendant_fees = 0
          descendant_size = 0
  
          ancestor_size = sum([mempool[tx]['size'] for tx in mempool])
          ancestor_count = MAX_ANCESTORS
          ancestor_fees = sum([mempool[tx]['fee'] for tx in mempool])
  
          descendants = []
          ancestors = list(chain)
          for x in reversed(chain):
              # Check that getmempoolentry is consistent with getrawmempool
              entry = self.nodes[0].getmempoolentry(x)
              assert_equal(entry, mempool[x])
  
              # Check that the descendant calculations are correct
              assert_equal(mempool[x]['descendantcount'], descendant_count)
              descendant_fees += mempool[x]['fee']
              assert_equal(mempool[x]['modifiedfee'], mempool[x]['fee'])
              assert_equal(mempool[x]['fees']['base'], mempool[x]['fee'])
              assert_equal(mempool[x]['fees']['modified'], mempool[x]['modifiedfee'])
              assert_equal(mempool[x]['descendantfees'], descendant_fees * COIN)
              assert_equal(mempool[x]['fees']['descendant'], descendant_fees)
              descendant_size += mempool[x]['size']
              assert_equal(mempool[x]['descendantsize'], descendant_size)
              descendant_count += 1
  
              # Check that ancestor calculations are correct
              assert_equal(mempool[x]['ancestorcount'], ancestor_count)
              assert_equal(mempool[x]['ancestorfees'], ancestor_fees * COIN)
              assert_equal(mempool[x]['ancestorsize'], ancestor_size)
              ancestor_size -= mempool[x]['size']
              ancestor_fees -= mempool[x]['fee']
              ancestor_count -= 1
  
              # Check that parent/child list is correct
              assert_equal(mempool[x]['spentby'], descendants[-1:])
              assert_equal(mempool[x]['depends'], ancestors[-2:-1])
  
              # Check that getmempooldescendants is correct
              assert_equal(sorted(descendants), sorted(self.nodes[0].getmempooldescendants(x)))
  
              # Check getmempooldescendants verbose output is correct
              for descendant, dinfo in self.nodes[0].getmempooldescendants(x, True).items():
                  assert_equal(dinfo['depends'], [chain[chain.index(descendant)-1]])
                  if dinfo['descendantcount'] > 1:
                      assert_equal(dinfo['spentby'], [chain[chain.index(descendant)+1]])
                  else:
                      assert_equal(dinfo['spentby'], [])
              descendants.append(x)
  
              # Check that getmempoolancestors is correct
              ancestors.remove(x)
              assert_equal(sorted(ancestors), sorted(self.nodes[0].getmempoolancestors(x)))
  
              # Check that getmempoolancestors verbose output is correct
              for ancestor, ainfo in self.nodes[0].getmempoolancestors(x, True).items():
                  assert_equal(ainfo['spentby'], [chain[chain.index(ancestor)+1]])
                  if ainfo['ancestorcount'] > 1:
                      assert_equal(ainfo['depends'], [chain[chain.index(ancestor)-1]])
                  else:
                      assert_equal(ainfo['depends'], [])
  
  
          # Check that getmempoolancestors/getmempooldescendants correctly handle verbose=true
          v_ancestors = self.nodes[0].getmempoolancestors(chain[-1], True)
          assert_equal(len(v_ancestors), len(chain)-1)
          for x in v_ancestors.keys():
              assert_equal(mempool[x], v_ancestors[x])
          assert(chain[-1] not in v_ancestors.keys())
  
          v_descendants = self.nodes[0].getmempooldescendants(chain[0], True)
          assert_equal(len(v_descendants), len(chain)-1)
          for x in v_descendants.keys():
              assert_equal(mempool[x], v_descendants[x])
          assert(chain[0] not in v_descendants.keys())
  
          # Check that ancestor modified fees includes fee deltas from
          # prioritisetransaction
          self.nodes[0].prioritisetransaction(txid=chain[0], fee_delta=1000)
          mempool = self.nodes[0].getrawmempool(True)
          ancestor_fees = 0
          for x in chain:
              ancestor_fees += mempool[x]['fee']
              assert_equal(mempool[x]['fees']['ancestor'], ancestor_fees + Decimal('0.00001'))
              assert_equal(mempool[x]['ancestorfees'], ancestor_fees * COIN + 1000)
  
          # Undo the prioritisetransaction for later tests
          self.nodes[0].prioritisetransaction(txid=chain[0], fee_delta=-1000)
  
          # Check that descendant modified fees includes fee deltas from
          # prioritisetransaction
          self.nodes[0].prioritisetransaction(txid=chain[-1], fee_delta=1000)
          mempool = self.nodes[0].getrawmempool(True)
  
          descendant_fees = 0
          for x in reversed(chain):
              descendant_fees += mempool[x]['fee']
              assert_equal(mempool[x]['fees']['descendant'], descendant_fees + Decimal('0.00001'))
              assert_equal(mempool[x]['descendantfees'], descendant_fees * COIN + 1000)
  
          # Adding one more transaction on to the chain should fail.
          assert_raises_rpc_error(-26, "too-long-mempool-chain", self.chain_transaction, self.nodes[0], txid, vout, value, fee, 1)
  
          # Check that prioritising a tx before it's added to the mempool works
          # First clear the mempool by mining a block.
          self.nodes[0].generate(1)
          sync_blocks(self.nodes)
          assert_equal(len(self.nodes[0].getrawmempool()), 0)
          # Prioritise a transaction that has been mined, then add it back to the
          # mempool by using invalidateblock.
          self.nodes[0].prioritisetransaction(txid=chain[-1], fee_delta=2000)
          self.nodes[0].invalidateblock(self.nodes[0].getbestblockhash())
          # Keep node1's tip synced with node0
          self.nodes[1].invalidateblock(self.nodes[1].getbestblockhash())
  
          # Now check that the transaction is in the mempool, with the right modified fee
          mempool = self.nodes[0].getrawmempool(True)
  
          descendant_fees = 0
          for x in reversed(chain):
              descendant_fees += mempool[x]['fee']
              if (x == chain[-1]):
                  assert_equal(mempool[x]['modifiedfee'], mempool[x]['fee']+satoshi_round(0.00002))
                  assert_equal(mempool[x]['fees']['modified'], mempool[x]['fee']+satoshi_round(0.00002))
              assert_equal(mempool[x]['descendantfees'], descendant_fees * COIN + 2000)
              assert_equal(mempool[x]['fees']['descendant'], descendant_fees+satoshi_round(0.00002))
  
          # TODO: check that node1's mempool is as expected
  
          # TODO: test ancestor size limits
  
          # Now test descendant chain limits
          txid = utxo[1]['txid']
          value = utxo[1]['amount']
          vout = utxo[1]['vout']
  
          transaction_package = []
          tx_children = []
          # First create one parent tx with 10 children
          (txid, sent_value) = self.chain_transaction(self.nodes[0], txid, vout, value, fee, 10)
          parent_transaction = txid
          for i in range(10):
              transaction_package.append({'txid': txid, 'vout': i, 'amount': sent_value})
  
          # Sign and send up to MAX_DESCENDANT transactions chained off the parent tx
          for i in range(MAX_DESCENDANTS - 1):
              utxo = transaction_package.pop(0)
              (txid, sent_value) = self.chain_transaction(self.nodes[0], utxo['txid'], utxo['vout'], utxo['amount'], fee, 10)
              if utxo['txid'] is parent_transaction:
                  tx_children.append(txid)
              for j in range(10):
                  transaction_package.append({'txid': txid, 'vout': j, 'amount': sent_value})
  
          mempool = self.nodes[0].getrawmempool(True)
          assert_equal(mempool[parent_transaction]['descendantcount'], MAX_DESCENDANTS)
          assert_equal(sorted(mempool[parent_transaction]['spentby']), sorted(tx_children))
  
          for child in tx_children:
              assert_equal(mempool[child]['depends'], [parent_transaction])
  
          # Sending one more chained transaction will fail
          utxo = transaction_package.pop(0)
          assert_raises_rpc_error(-26, "too-long-mempool-chain", self.chain_transaction, self.nodes[0], utxo['txid'], utxo['vout'], utxo['amount'], fee, 10)
  
          # TODO: check that node1's mempool is as expected
  
          # TODO: test descendant size limits
  
          # Test reorg handling
          # First, the basics:
          self.nodes[0].generate(1)
          sync_blocks(self.nodes)
          self.nodes[1].invalidateblock(self.nodes[0].getbestblockhash())
          self.nodes[1].reconsiderblock(self.nodes[0].getbestblockhash())
  
          # Now test the case where node1 has a transaction T in its mempool that
          # depends on transactions A and B which are in a mined block, and the
          # block containing A and B is disconnected, AND B is not accepted back
          # into node1's mempool because its ancestor count is too high.
  
          # Create 8 transactions, like so:
          # Tx0 -> Tx1 (vout0)
          #   \--> Tx2 (vout1) -> Tx3 -> Tx4 -> Tx5 -> Tx6 -> Tx7
          #
          # Mine them in the next block, then generate a new tx8 that spends
          # Tx1 and Tx7, and add to node1's mempool, then disconnect the
          # last block.
  
          # Create tx0 with 2 outputs
          utxo = self.nodes[0].listunspent()
          txid = utxo[0]['txid']
          value = utxo[0]['amount']
          vout = utxo[0]['vout']
  
          send_value = satoshi_round((value - fee)/2)
          inputs = [ {'txid' : txid, 'vout' : vout} ]
          outputs = {}
          for i in range(2):
              outputs[self.nodes[0].getnewaddress()] = send_value
          rawtx = self.nodes[0].createrawtransaction(inputs, outputs)
          signedtx = self.nodes[0].signrawtransactionwithwallet(rawtx)
          txid = self.nodes[0].sendrawtransaction(signedtx['hex'])
          tx0_id = txid
          value = send_value
  
          # Create tx1
          tx1_id, _ = self.chain_transaction(self.nodes[0], tx0_id, 0, value, fee, 1)
  
          # Create tx2-7
          vout = 1
          txid = tx0_id
          for i in range(6):
              (txid, sent_value) = self.chain_transaction(self.nodes[0], txid, vout, value, fee, 1)
              vout = 0
              value = sent_value
  
          # Mine these in a block
          self.nodes[0].generate(1)
          self.sync_all()
  
          # Now generate tx8, with a big fee
          inputs = [ {'txid' : tx1_id, 'vout': 0}, {'txid' : txid, 'vout': 0} ]
          outputs = { self.nodes[0].getnewaddress() : send_value + value - 4*fee }
          rawtx = self.nodes[0].createrawtransaction(inputs, outputs)
          signedtx = self.nodes[0].signrawtransactionwithwallet(rawtx)
          txid = self.nodes[0].sendrawtransaction(signedtx['hex'])
          sync_mempools(self.nodes)
  
          # Now try to disconnect the tip on each node...
          self.nodes[1].invalidateblock(self.nodes[1].getbestblockhash())
          self.nodes[0].invalidateblock(self.nodes[0].getbestblockhash())
          sync_blocks(self.nodes)
  
  if __name__ == '__main__':
      MempoolPackagesTest().main()
  