dash/test/functional/mempool_package_onemore.py
fanquake 9d33b30a87
Merge #19674: refactor: test: use throwaway _ variable for unused loop counters
dac7a111bdd3b0233d94cf68dae7a8bfc6ac9c64 refactor: test: use _ variable for unused loop counters (Sebastian Falbesoner)

Pull request description:

  This tiny PR substitutes Python loops in the form of `for x in range(N): ...` by `for _ in range(N): ...` where applicable. The idea is indicating to the reader that a block (or statement, in list comprehensions) is just repeated N times, and that the loop counter is not used in the body, hence using the throwaway variable. This is already done quite often in the current tests (see e.g. `$ git grep "for _ in range("`). Another alternative would be using `itertools.repeat` (according to Python core developer Raymond Hettinger it's [even faster](https://twitter.com/raymondh/status/1144527183341375488)), but that doesn't seem to be widespread in use and I'm not sure about a readability increase.

  The only drawback I see is that whenever one wants to debug loop iterations, one would need to introduce a loop variable again. Reviewing this is basically a no-brainer, since tests would fail immediately if a a substitution has taken place on a loop where the variable is used.

  Instances to replace were found by `$ git grep "for.*in range("` and manually checked.

ACKs for top commit:
  darosior:
    ACK dac7a111bdd3b0233d94cf68dae7a8bfc6ac9c64
  instagibbs:
    manual inspection ACK dac7a111bd
  practicalswift:
    ACK dac7a111bdd3b0233d94cf68dae7a8bfc6ac9c64 -- the updated code is easier to reason about since the throwaway nature of a variable is expressed explicitly (using the Pythonic `_` idiom) instead of implicitly. Explicit is better than implicit was we all know by now :)

Tree-SHA512: 5f43ded9ce14e5e00b3876ec445b90acda1842f813149ae7bafa93f3ac3d510bb778e2c701187fd2c73585e6b87797bb2d2987139bd1a9ba7d58775a59392406
2024-01-20 00:07:09 +07:00

88 lines
4.4 KiB
Python
Executable File

#!/usr/bin/env python3
# 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 descendant package tracking carve-out allowing one final transaction in
an otherwise-full package as long as it has only one parent and is <= 10k in
size.
"""
from decimal import Decimal
from test_framework.blocktools import COINBASE_MATURITY
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import assert_equal, assert_raises_rpc_error, satoshi_round
MAX_ANCESTORS = 25
MAX_DESCENDANTS = 25
class MempoolPackagesTest(BitcoinTestFramework):
def set_test_params(self):
self.num_nodes = 1
self.extra_args = [["-maxorphantxsize=100000"]]
def skip_test_if_missing_module(self):
self.skip_if_no_wallet()
# Build a transaction that spends parent_txid:vout
# Return amount sent
def chain_transaction(self, node, parent_txids, vouts, value, fee, num_outputs):
send_value = satoshi_round((value - fee)/num_outputs)
inputs = []
for (txid, vout) in zip(parent_txids, vouts):
inputs.append({'txid' : txid, 'vout' : vout})
outputs = {}
for _ 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(COINBASE_MATURITY + 1)
utxo = self.nodes[0].listunspent(10)
txid = utxo[0]['txid']
vout = utxo[0]['vout']
value = utxo[0]['amount']
fee = Decimal("0.0002")
# MAX_ANCESTORS transactions off a confirmed tx should be fine
chain = []
for _ in range(4):
(txid, sent_value) = self.chain_transaction(self.nodes[0], [txid], [vout], value, fee, 2)
vout = 0
value = sent_value
chain.append([txid, value])
for _ in range(MAX_ANCESTORS - 4):
(txid, sent_value) = self.chain_transaction(self.nodes[0], [txid], [0], value, fee, 1)
value = sent_value
chain.append([txid, value])
(second_chain, second_chain_value) = self.chain_transaction(self.nodes[0], [utxo[1]['txid']], [utxo[1]['vout']], utxo[1]['amount'], fee, 1)
# Check mempool has MAX_ANCESTORS + 1 transactions in it
assert_equal(len(self.nodes[0].getrawmempool(True)), MAX_ANCESTORS + 1)
# Adding one more transaction on to the chain should fail.
assert_raises_rpc_error(-26, "too-long-mempool-chain, too many unconfirmed ancestors [limit: 25]", self.chain_transaction, self.nodes[0], [txid], [0], value, fee, 1)
# ...even if it chains on from some point in the middle of the chain.
assert_raises_rpc_error(-26, "too-long-mempool-chain, too many descendants", self.chain_transaction, self.nodes[0], [chain[2][0]], [1], chain[2][1], fee, 1)
assert_raises_rpc_error(-26, "too-long-mempool-chain, too many descendants", self.chain_transaction, self.nodes[0], [chain[1][0]], [1], chain[1][1], fee, 1)
# ...even if it chains on to two parent transactions with one in the chain.
assert_raises_rpc_error(-26, "too-long-mempool-chain, too many descendants", self.chain_transaction, self.nodes[0], [chain[0][0], second_chain], [1, 0], chain[0][1] + second_chain_value, fee, 1)
# ...especially if its > 40k weight
assert_raises_rpc_error(-26, "too-long-mempool-chain, too many descendants", self.chain_transaction, self.nodes[0], [chain[0][0]], [1], chain[0][1], fee, 350)
# But not if it chains directly off the first transaction
self.chain_transaction(self.nodes[0], [chain[0][0]], [1], chain[0][1], fee, 1)
# and the second chain should work just fine
self.chain_transaction(self.nodes[0], [second_chain], [0], second_chain_value, fee, 1)
# Finally, check that we added two transactions
assert_equal(len(self.nodes[0].getrawmempool(True)), MAX_ANCESTORS + 3)
if __name__ == '__main__':
MempoolPackagesTest().main()