Merge bitcoin/bitcoin#29496: policy: bump TX_MAX_STANDARD_VERSION to 3

30a01134cdec37e7467fcd6eee8b0ae3890a131c [doc] update bips.md for 431 (glozow)
9dbe6a03f0d6e70ccdf8e8715f888c0c17216bee [test] wallet uses CURRENT_VERSION which is 2 (glozow)
539404fe0fc0346b3aa77c330b38a5a0ad6565b2 [policy] make v3 transactions standard (glozow)
052ede75aff5c9f3a0a422ef413852eabeecc665 [refactor] use TRUC_VERSION in place of 3 (glozow)

Pull request description:

  Make `nVersion=3` (which is currently nonstandard on mainnet) standard.

  Note that we will treat these transactions as Topologically Restricted Until Confirmation (TRUC). Spec is in BIP 431 and implementation is in #28948, #29306, and #29873

  See #27463 for overall project tracking, and #29319 for information about relevance to cluster mempool.

ACKs for top commit:
  sdaftuar:
    utACK 30a01134c
  achow101:
    ACK 30a01134cdec37e7467fcd6eee8b0ae3890a131c
  instagibbs:
    utACK 30a01134cdec37e7467fcd6eee8b0ae3890a131c
  murchandamus:
    ACK 30a01134cdec37e7467fcd6eee8b0ae3890a131c
  ismaelsadeeq:
    ACK 30a01134cdec37e7467fcd6eee8b0ae3890a131c 🛰️

Tree-SHA512: 2a4aec0442c860e792a061d83e36483c1f1b426f946efbdf664c8db97a596e498b535707e1d3a900218429486ea69fd4552e3d476526a6883cbd5556c6534b48

3 files changed, 38 insertions, 17 deletions

diff --git a/test/functional/mempool_accept.py b/test/functional/mempool_accept.py
index b00be5f4f0..2de4cf1e10 100755
--- a/test/functional/mempool_accept.py
+++ b/test/functional/mempool_accept.py
@@ -287,7 +287,7 @@ class MempoolAcceptanceTest(BitcoinTestFramework):
 
         self.log.info('Some nonstandard transactions')
         tx = tx_from_hex(raw_tx_reference)
-        tx.nVersion = 3  # A version currently non-standard
+        tx.nVersion = 4  # A version currently non-standard
         self.check_mempool_result(
             result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': 'version'}],
             rawtxs=[tx.serialize().hex()],
diff --git a/test/functional/mempool_accept_v3.py b/test/functional/mempool_accept_v3.py
index 6b0ba0812b..d4a33c232e 100755
--- a/test/functional/mempool_accept_v3.py
+++ b/test/functional/mempool_accept_v3.py
@@ -42,7 +42,7 @@ def cleanup(extra_args=None):
 class MempoolAcceptV3(BitcoinTestFramework):
     def set_test_params(self):
         self.num_nodes = 1
-        self.extra_args = [["-acceptnonstdtxn=1"]]
+        self.extra_args = [[]]
         self.setup_clean_chain = True
 
     def check_mempool(self, txids):
@@ -51,7 +51,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         assert_equal(len(txids), len(mempool_contents))
         assert all([txid in txids for txid in mempool_contents])
 
-    @cleanup(extra_args=["-datacarriersize=20000", "-acceptnonstdtxn=1"])
+    @cleanup(extra_args=["-datacarriersize=20000"])
     def test_v3_max_vsize(self):
         node = self.nodes[0]
         self.log.info("Test v3-specific maximum transaction vsize")
@@ -65,7 +65,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         tx_v2_heavy = self.wallet.send_self_transfer(from_node=node, target_weight=(V3_MAX_VSIZE + 1) * WITNESS_SCALE_FACTOR, version=2)
         self.check_mempool([tx_v2_heavy["txid"]])
 
-    @cleanup(extra_args=["-datacarriersize=1000", "-acceptnonstdtxn=1"])
+    @cleanup(extra_args=["-datacarriersize=1000"])
     def test_v3_acceptance(self):
         node = self.nodes[0]
         self.log.info("Test a child of a v3 transaction cannot be more than 1000vB")
@@ -105,7 +105,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         self.check_mempool([tx_v3_parent_normal["txid"], tx_v3_child_almost_heavy_rbf["txid"]])
         assert_equal(node.getmempoolentry(tx_v3_parent_normal["txid"])["descendantcount"], 2)
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_v3_replacement(self):
         node = self.nodes[0]
         self.log.info("Test v3 transactions may be replaced by v3 transactions")
@@ -162,7 +162,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         self.check_mempool([tx_v3_bip125_rbf_v2["txid"], tx_v3_parent["txid"], tx_v3_child["txid"]])
 
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_v3_bip125(self):
         node = self.nodes[0]
         self.log.info("Test v3 transactions that don't signal BIP125 are replaceable")
@@ -186,7 +186,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         )
         self.check_mempool([tx_v3_no_bip125_rbf["txid"]])
 
-    @cleanup(extra_args=["-datacarriersize=40000", "-acceptnonstdtxn=1"])
+    @cleanup(extra_args=["-datacarriersize=40000"])
     def test_v3_reorg(self):
         node = self.nodes[0]
         self.log.info("Test that, during a reorg, v3 rules are not enforced")
@@ -208,7 +208,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         node.reconsiderblock(block[0])
 
 
-    @cleanup(extra_args=["-limitdescendantsize=10", "-datacarriersize=40000", "-acceptnonstdtxn=1"])
+    @cleanup(extra_args=["-limitdescendantsize=10", "-datacarriersize=40000"])
     def test_nondefault_package_limits(self):
         """
         Max standard tx size + v3 rules imply the ancestor/descendant rules (at their default
@@ -241,7 +241,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         self.generate(node, 1)
 
         self.log.info("Test that a decreased limitancestorsize also applies to v3 parent")
-        self.restart_node(0, extra_args=["-limitancestorsize=10", "-datacarriersize=40000", "-acceptnonstdtxn=1"])
+        self.restart_node(0, extra_args=["-limitancestorsize=10", "-datacarriersize=40000"])
         tx_v3_parent_large2 = self.wallet.send_self_transfer(
             from_node=node,
             target_weight=parent_target_weight,
@@ -261,7 +261,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         assert_raises_rpc_error(-26, f"too-long-mempool-chain, exceeds ancestor size limit", node.sendrawtransaction, tx_v3_child_large2["hex"])
         self.check_mempool([tx_v3_parent_large2["txid"]])
 
-    @cleanup(extra_args=["-datacarriersize=1000", "-acceptnonstdtxn=1"])
+    @cleanup(extra_args=["-datacarriersize=1000"])
     def test_v3_ancestors_package(self):
         self.log.info("Test that v3 ancestor limits are checked within the package")
         node = self.nodes[0]
@@ -304,7 +304,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         result = node.testmempoolaccept([tx_v3_parent["hex"], tx_v3_child["hex"], tx_v3_grandchild["hex"]])
         assert all([txresult["package-error"] == f"v3-violation, tx {tx_v3_grandchild['txid']} (wtxid={tx_v3_grandchild['wtxid']}) would have too many ancestors" for txresult in result])
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_v3_ancestors_package_and_mempool(self):
         """
         A v3 transaction in a package cannot have 2 v3 parents.
@@ -334,7 +334,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         assert_equal(result['package_msg'], f"v3-violation, tx {tx_child_violator['txid']} (wtxid={tx_child_violator['wtxid']}) would have too many ancestors")
         self.check_mempool([tx_in_mempool["txid"]])
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_sibling_eviction_package(self):
         """
         When a transaction has a mempool sibling, it may be eligible for sibling eviction.
@@ -410,7 +410,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         assert_equal(result_package_cpfp["tx-results"][tx_sibling_3['wtxid']]['error'], expected_error_cpfp)
 
 
-    @cleanup(extra_args=["-datacarriersize=1000", "-acceptnonstdtxn=1"])
+    @cleanup(extra_args=["-datacarriersize=1000"])
     def test_v3_package_inheritance(self):
         self.log.info("Test that v3 inheritance is checked within package")
         node = self.nodes[0]
@@ -429,7 +429,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         assert_equal(result['package_msg'], f"v3-violation, non-v3 tx {tx_v2_child['txid']} (wtxid={tx_v2_child['wtxid']}) cannot spend from v3 tx {tx_v3_parent['txid']} (wtxid={tx_v3_parent['wtxid']})")
         self.check_mempool([])
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_v3_in_testmempoolaccept(self):
         node = self.nodes[0]
 
@@ -479,7 +479,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         test_accept_2children_with_in_mempool_parent = node.testmempoolaccept([tx_v3_child_1["hex"], tx_v3_child_2["hex"]])
         assert all([result["package-error"] == expected_error_extra for result in test_accept_2children_with_in_mempool_parent])
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_reorg_2child_rbf(self):
         node = self.nodes[0]
         self.log.info("Test that children of a v3 transaction can be replaced individually, even if there are multiple due to reorg")
@@ -510,7 +510,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         self.check_mempool([ancestor_tx["txid"], child_1_conflict["txid"], child_2["txid"]])
         assert_equal(node.getmempoolentry(ancestor_tx["txid"])["descendantcount"], 3)
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_v3_sibling_eviction(self):
         self.log.info("Test sibling eviction for v3")
         node = self.nodes[0]
@@ -583,7 +583,7 @@ class MempoolAcceptV3(BitcoinTestFramework):
         node.sendrawtransaction(tx_v3_child_3["hex"])
         self.check_mempool(txids_v2_100 + [tx_v3_parent["txid"], tx_v3_child_3["txid"]])
 
-    @cleanup(extra_args=["-acceptnonstdtxn=1"])
+    @cleanup(extra_args=None)
     def test_reorg_sibling_eviction_1p2c(self):
         node = self.nodes[0]
         self.log.info("Test that sibling eviction is not allowed when multiple siblings exist")
diff --git a/test/functional/wallet_create_tx.py b/test/functional/wallet_create_tx.py
index 4e31b48ec0..fb1ee3ae61 100755
--- a/test/functional/wallet_create_tx.py
+++ b/test/functional/wallet_create_tx.py
@@ -3,6 +3,9 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+from test_framework.messages import (
+    tx_from_hex,
+)
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
@@ -33,6 +36,7 @@ class CreateTxWalletTest(BitcoinTestFramework):
         self.test_anti_fee_sniping()
         self.test_tx_size_too_large()
         self.test_create_too_long_mempool_chain()
+        self.test_version3()
 
     def test_anti_fee_sniping(self):
         self.log.info('Check that we have some (old) blocks and that anti-fee-sniping is disabled')
@@ -106,6 +110,23 @@ class CreateTxWalletTest(BitcoinTestFramework):
 
         test_wallet.unloadwallet()
 
+    def test_version3(self):
+        self.log.info('Check wallet does not create transactions with nVersion=3 yet')
+        wallet_rpc = self.nodes[0].get_wallet_rpc(self.default_wallet_name)
+
+        self.nodes[0].createwallet("v3")
+        wallet_v3 = self.nodes[0].get_wallet_rpc("v3")
+
+        tx_data = wallet_rpc.send(outputs=[{wallet_v3.getnewaddress(): 25}], options={"change_position": 0})
+        wallet_tx_data = wallet_rpc.gettransaction(tx_data["txid"])
+        tx_current_version = tx_from_hex(wallet_tx_data["hex"])
+
+        # While v3 transactions are standard, the CURRENT_VERSION is 2.
+        # This test can be removed if CURRENT_VERSION is changed, and replaced with tests that the
+        # wallet handles v3 rules properly.
+        assert_equal(tx_current_version.nVersion, 2)
+        wallet_v3.unloadwallet()
+
 
 if __name__ == '__main__':
     CreateTxWalletTest().main()