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 gettxoutproof and verifytxoutproof RPCs."""
  
  from test_framework.messages import CMerkleBlock, FromHex, ToHex
  from test_framework.test_framework import XcoinTestFramework
  from test_framework.util import assert_equal, assert_raises_rpc_error, connect_nodes
  
  class MerkleBlockTest(XcoinTestFramework):
      def set_test_params(self):
          self.num_nodes = 4
          self.setup_clean_chain = True
          # Nodes 0/1 are "wallet" nodes, Nodes 2/3 are used for testing
          self.extra_args = [[], [], [], ["-txindex"]]
  
      def skip_test_if_missing_module(self):
          self.skip_if_no_wallet()
  
      def setup_network(self):
          self.setup_nodes()
          connect_nodes(self.nodes[0], 1)
          connect_nodes(self.nodes[0], 2)
          connect_nodes(self.nodes[0], 3)
  
          self.sync_all()
  
      def run_test(self):
          self.log.info("Mining blocks...")
          self.nodes[0].generate(105)
          self.sync_all()
  
          chain_height = self.nodes[1].getblockcount()
          assert_equal(chain_height, 105)
          assert_equal(self.nodes[1].getbalance(), 0)
          assert_equal(self.nodes[2].getbalance(), 0)
  
          node0utxos = self.nodes[0].listunspent(1)
          tx1 = self.nodes[0].createrawtransaction([node0utxos.pop()], {self.nodes[1].getnewaddress(): 49.99})
          txid1 = self.nodes[0].sendrawtransaction(self.nodes[0].signrawtransactionwithwallet(tx1)["hex"])
          tx2 = self.nodes[0].createrawtransaction([node0utxos.pop()], {self.nodes[1].getnewaddress(): 49.99})
          txid2 = self.nodes[0].sendrawtransaction(self.nodes[0].signrawtransactionwithwallet(tx2)["hex"])
          # This will raise an exception because the transaction is not yet in a block
          assert_raises_rpc_error(-5, "Transaction not yet in block", self.nodes[0].gettxoutproof, [txid1])
  
          self.nodes[0].generate(1)
          blockhash = self.nodes[0].getblockhash(chain_height + 1)
          self.sync_all()
  
          txlist = []
          blocktxn = self.nodes[0].getblock(blockhash, True)["tx"]
          txlist.append(blocktxn[1])
          txlist.append(blocktxn[2])
  
          assert_equal(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid1])), [txid1])
          assert_equal(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid1, txid2])), txlist)
          assert_equal(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid1, txid2], blockhash)), txlist)
  
          txin_spent = self.nodes[1].listunspent(1).pop()
          tx3 = self.nodes[1].createrawtransaction([txin_spent], {self.nodes[0].getnewaddress(): 49.98})
          txid3 = self.nodes[0].sendrawtransaction(self.nodes[1].signrawtransactionwithwallet(tx3)["hex"])
          self.nodes[0].generate(1)
          self.sync_all()
  
          txid_spent = txin_spent["txid"]
          txid_unspent = txid1 if txin_spent["txid"] != txid1 else txid2
  
          # We can't find the block from a fully-spent tx
          assert_raises_rpc_error(-5, "Transaction not yet in block", self.nodes[2].gettxoutproof, [txid_spent])
          # We can get the proof if we specify the block
          assert_equal(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid_spent], blockhash)), [txid_spent])
          # We can't get the proof if we specify a non-existent block
          assert_raises_rpc_error(-5, "Block not found", self.nodes[2].gettxoutproof, [txid_spent], "00000000000000000000000000000000")
          # We can get the proof if the transaction is unspent
          assert_equal(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid_unspent])), [txid_unspent])
          # We can get the proof if we provide a list of transactions and one of them is unspent. The ordering of the list should not matter.
          assert_equal(sorted(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid1, txid2]))), sorted(txlist))
          assert_equal(sorted(self.nodes[2].verifytxoutproof(self.nodes[2].gettxoutproof([txid2, txid1]))), sorted(txlist))
          # We can always get a proof if we have a -txindex
          assert_equal(self.nodes[2].verifytxoutproof(self.nodes[3].gettxoutproof([txid_spent])), [txid_spent])
          # We can't get a proof if we specify transactions from different blocks
          assert_raises_rpc_error(-5, "Not all transactions found in specified or retrieved block", self.nodes[2].gettxoutproof, [txid1, txid3])
  
          # Now we'll try tweaking a proof.
          proof = self.nodes[3].gettxoutproof([txid1, txid2])
          assert txid1 in self.nodes[0].verifytxoutproof(proof)
          assert txid2 in self.nodes[1].verifytxoutproof(proof)
  
          tweaked_proof = FromHex(CMerkleBlock(), proof)
  
          # Make sure that our serialization/deserialization is working
          assert txid1 in self.nodes[2].verifytxoutproof(ToHex(tweaked_proof))
  
          # Check to see if we can go up the merkle tree and pass this off as a
          # single-transaction block
          tweaked_proof.txn.nTransactions = 1
          tweaked_proof.txn.vHash = [tweaked_proof.header.hashMerkleRoot]
          tweaked_proof.txn.vBits = [True] + [False]*7
  
          for n in self.nodes:
              assert not n.verifytxoutproof(ToHex(tweaked_proof))
  
          # TODO: try more variants, eg transactions at different depths, and
          # verify that the proofs are invalid
  
  if __name__ == '__main__':
      MerkleBlockTest().main()
  