In `p2p_private_broadcast.py` in the function `check_broadcasts()` we
should assert that the broadcast was done to `broadcasts_to_expect`
peers, not to `NUM_PRIVATE_BROADCAST_PER_TX`. This is because in the
"Basic" test we check the first broadcast manually because it is done to
`nodes[1]` and then check the other two by
`check_broadcasts(..., NUM_PRIVATE_BROADCAST_PER_TX - 1, ...)`.
The first broadcast might not have fully concluded by the time we call
`check_broadcasts()` to check the remaining 2.
Demanding always `NUM_PRIVATE_BROADCAST_PER_TX` can lead to:
```
Traceback (most recent call last):
File "/home/vd/gh/bitcoin/bitcoin/test/functional/test_framework/test_framework.py", line 142, in main
self.run_test()
~~~~~~~~~~~~~^^
File "/tmp/build/clang22/test/functional/p2p_private_broadcast.py", line 347, in run_test
self.check_broadcasts("Basic", txs[0], NUM_PRIVATE_BROADCAST_PER_TX - 1, NUM_INITIAL_CONNECTIONS + 1)
~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/tmp/build/clang22/test/functional/p2p_private_broadcast.py", line 313, in check_broadcasts
assert_greater_than_or_equal(sum(1 for p in peers if "received" in p), NUM_PRIVATE_BROADCAST_PER_TX)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/vd/gh/bitcoin/bitcoin/test/functional/test_framework/util.py", line 94, in assert_greater_than_or_equal
raise AssertionError("%s < %s" % (str(thing1), str(thing2)))
AssertionError: 2 < 3
```
The piece of `p2p_private_broadcast.py` which tests the correctness of
`abortprivatebroadcast` issues a new `sendrawtransaction` call. That
call schedules up to 3 new connections: peer=13, peer=14 and possibly
peer=15 before it gets aborted.
These up to 3 in-the-process-of-opening private broadcast connections
have `CNode::m_connected` set early - when the `CNode` object is
created. Later in the test the mock time is advanced by 20 minutes and
those "old" connections pick a transaction for rebroadcast but that
triggers `PRIVATE_BROADCAST_MAX_CONNECTION_LIFETIME` immediately:
```
2026-02-21T13:28:14.209766Z [privbcast] [net.cpp:4006] [CNode] [net] Added connection peer=20
2026-02-21T13:28:14.309792Z (mocktime: 2026-02-21T13:48:14Z) [msghand] [net.cpp:4074] [PushMessage] [net] sending inv (37 bytes) peer=20
2026-02-21T13:28:14.309801Z (mocktime: 2026-02-21T13:48:14Z) [msghand] [net_processing.cpp:5745] [SendMessages] [privatebroadcast] Disconnecting: did not complete the transaction send within 180 seconds, peer=20
```
This prematurely stops the private broadcast connection and results in
a failure like:
```
AssertionError: ... not({} == {'ping': 1, 'tx': 1})
```
3f5211cba8e73e8eb03781e6ec32ba9c4a263782 test: remove child_one/child_two (w)txid variables (naiyoma)
7cfe790820cf247e8a27bb8091defc54c74d6aec test: replace ValidWitnessMalleatedTx class with function (naiyoma)
81675a781f3ab62a0576a9739d13b4997b63230d test: use pre-generated chain (naiyoma)
Pull request description:
This PR refactors ` ValidWitnessMalleatedTx` class into a `build_malleated_tx_package` function. As a result, two tests are updated: `mempool_accept_wtxid` and `p2p_p2p_private_broadcast`. Also included are a few small refactors in mempool_accept_wtxid , (switching to MiniWallet, using a pre-mined chain, using txid directly.)
Together, these changes reduce complexity and improve test runtime.
ACKs for top commit:
stratospher:
reACK 3f5211c.
cedwies:
reACK 3f5211c
maflcko:
review ACK 3f5211cba8e73e8eb03781e6ec32ba9c4a263782 👥
rkrux:
ACK 3f5211cba8e73e8eb03781e6ec32ba9c4a263782
Tree-SHA512: 1fd02be3432fef6b68e54fbe8b15ed56d2699580bb13d0777b21f9cbe4c6d33bbb710541e3ca2fc93eab771d17bf1c427e4b08fa216d561bdb320cc6b36ac8fc
Simplify the witness malleation test helper by converting the
ValidWitnessMalleatedTx class to a standalone function
build_malleated_tx_package() and updating call sites.
Co-authored-by: rkrux <rkrux.connect@gmail.com>
The test `p2p_private_broadcast.py` gets some Python P2P nodes to listen
and instructs the SOCKS5 proxy to redirect connections to them instead
of to the requested addresses. This way the `bitcoind` which uses the
proxy is tricked to think it has connected to real routable internet
IP addresses or `.onion` addresses.
Picking the ports where to Python P2P nodes to listen however is tricky
to be done in a non-conflicting way, given that other tests may run in
parallel. https://github.com/bitcoin/bitcoin/pull/34186 made it possible
to let the OS select a free port, so use that in
`p2p_private_broadcast.py`.
