Repository: bitcoin/bitcoin
File: test/functional/mempool_accept_wtxid.py (Python)

Code before:
#!/usr/bin/env python3
# Copyright (c) 2021 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 mempool acceptance in case of an already known transaction
with identical non-witness data but different witness.
"""

from test_framework.messages import (
    COIN,
)
from test_framework.p2p import P2PTxInvStore
from test_framework.script_util import ValidWitnessMalleatedTx
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import (
    assert_not_equal,
    assert_equal,
)


class MempoolWtxidTest(BitcoinTestFramework):
    def set_test_params(self):
        self.num_nodes = 1
        self.setup_clean_chain = False

    def run_test(self):
        node = self.nodes[0]
        self.log.info('Start with pre-generated blocks')
        blockhash = self.nodes[0].getblockhash(1)
        txid = node.getblock(blockhash=blockhash, verbosity=2)["tx"][0]["txid"]
        assert_equal(node.getmempoolinfo()['size'], 0)

        self.log.info("Submit parent with multiple script branches to mempool")
        txgen = ValidWitnessMalleatedTx()
        parent = txgen.build_parent_tx(txid, 9.99998 * COIN)

        privkeys = [node.get_deterministic_priv_key().key]
        raw_parent = node.signrawtransactionwithkey(hexstring=parent.serialize().hex(), privkeys=privkeys)['hex']
        signed_parent_txid = node.sendrawtransaction(hexstring=raw_parent, maxfeerate=0)
        self.generate(node, 1)

        peer_wtxid_relay = node.add_p2p_connection(P2PTxInvStore())

        child_one, child_two = txgen.build_malleated_children(signed_parent_txid, 9.99996 * COIN)
        child_one_wtxid = child_one.wtxid_hex
        child_one_txid = child_one.txid_hex
        child_two_wtxid = child_two.wtxid_hex
        child_two_txid = child_two.txid_hex


Review comment (refactor):
In 26577cac8b9cf53d5f69e4502346fd5881c92004 "test: use pre-generated chain"

Nit (not strong opinion): Can remove this line altogether as well because `False` is the default value.

Code after:
#!/usr/bin/env python3
# Copyright (c) 2021-present 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 mempool acceptance in case of an already known transaction
with identical non-witness data but different witness.
"""

from test_framework.p2p import P2PTxInvStore
from test_framework.script_util import build_malleated_tx_package
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import (
    assert_not_equal,
    assert_equal,
)
from test_framework.wallet import (
    MiniWallet,
)

class MempoolWtxidTest(BitcoinTestFramework):
    def set_test_params(self):
        self.num_nodes = 1

    def run_test(self):
        node = self.nodes[0]
        mini_wallet = MiniWallet(node)
        self.log.info('Start with pre-generated blocks')

        assert_equal(node.getmempoolinfo()['size'], 0)

        self.log.info("Submit parent with multiple script branches to mempool")

        parent = mini_wallet.create_self_transfer()["tx"]
        parent_amount = parent.vout[0].nValue - 10000
        child_amount = parent_amount - 10000
        parent, child_one, child_two = build_malleated_tx_package(
            parent=parent,
            rebalance_parent_output_amount=parent_amount,
            child_amount=child_amount
        )

        mini_wallet.sendrawtransaction(from_node=node, tx_hex=parent.serialize().hex())

        self.generate(node, 1)

        peer_wtxid_relay = node.add_p2p_connection(P2PTxInvStore())

        assert_equal(child_one.txid_hex, child_two.txid_hex)
        assert_not_equal(child_one.wtxid_hex, child_two.wtxid_hex)