Merge bitcoin/bitcoin#25228: test: add BIP-125 rule 5 testcase with default mempool

687addaf136356e0f3698d6345c92d875e0a3362 test: add BIP-125 rule 5 testcase with default mempool (James O'Beirne)
6120e8e2871fecfec5ab3099c97e13951e062a4d test: allow passing sequence through create_self_transfer_multi (James O'Beirne)

Pull request description:

  Currently, we only test rule 5 of BIP-125 (replacement transactions cannot evict more than 100 transactions) by changing default mempool parameters to allow for more descendants. The current test works on a single transaction graph that has over 100 descendants.

  This patch adds a test to exercise rule 5 using the default mempool parameters. The case is a little more sophisticated: instead of working on a single transaction graph, it uses a replacement transaction to "unite" several UTXOs which join independent transaction graphs. The total number of transactions in these graphs sum to more than the max allowable replacement.

  I think the difference in transaction topology makes this a worthwhile testcase to have, setting aside the fact that this testcase works without having to use atypical mempool params.

  See also: [relevant discussion from IRC](https://www.erisian.com.au/bitcoin-core-dev/log-2022-05-27.html#l-126)

ACKs for top commit:
  laanwj:
    Code review ACK 687addaf136356e0f3698d6345c92d875e0a3362
  LarryRuane:
    ACK 687addaf136356e0f3698d6345c92d875e0a3362

Tree-SHA512: e589aeaf9d6f137d546b7809f8795d6f6043d87b15e97c2efe85b42ce8b49d977ee7d79440c542ca4b0b5ca2de527488029841a1ffc0d96c5771897df4b3f324

1 files changed, 11 insertions, 3 deletions

diff --git a/test/functional/test_framework/wallet.py b/test/functional/test_framework/wallet.py
index 336b2afe26..e43dd9f61a 100644
--- a/test/functional/test_framework/wallet.py
+++ b/test/functional/test_framework/wallet.py
@@ -10,6 +10,7 @@ from enum import Enum
 from random import choice
 from typing import (
     Any,
+    List,
     Optional,
 )
 from test_framework.address import (
@@ -147,7 +148,7 @@ class MiniWallet:
     def get_address(self):
         return self._address
 
-    def get_utxo(self, *, txid: str = '', vout: Optional[int] = None, mark_as_spent=True):
+    def get_utxo(self, *, txid: str = '', vout: Optional[int] = None, mark_as_spent=True) -> dict:
         """
         Returns a utxo and marks it as spent (pops it from the internal list)
 
@@ -215,14 +216,21 @@ class MiniWallet:
         return {'new_utxos': [self.get_utxo(txid=txid, vout=vout) for vout in range(len(tx.vout))],
                 'txid': txid, 'hex': tx.serialize().hex(), 'tx': tx}
 
-    def create_self_transfer_multi(self, *, from_node, utxos_to_spend=None, num_outputs=1, fee_per_output=1000):
+    def create_self_transfer_multi(
+            self, *, from_node,
+            utxos_to_spend: Optional[List[dict]] = None,
+            num_outputs=1,
+            sequence=0,
+            fee_per_output=1000):
         """
         Create and return a transaction that spends the given UTXOs and creates a
         certain number of outputs with equal amounts.
         """
         utxos_to_spend = utxos_to_spend or [self.get_utxo()]
         # create simple tx template (1 input, 1 output)
-        tx = self.create_self_transfer(fee_rate=0, from_node=from_node, utxo_to_spend=utxos_to_spend[0], mempool_valid=False)['tx']
+        tx = self.create_self_transfer(
+            fee_rate=0, from_node=from_node,
+            utxo_to_spend=utxos_to_spend[0], sequence=sequence, mempool_valid=False)['tx']
 
         # duplicate inputs, witnesses and outputs
         tx.vin = [deepcopy(tx.vin[0]) for _ in range(len(utxos_to_spend))]