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authorJohn Newbery <john@johnnewbery.com>2017-03-08 15:56:30 -0500
committerJohn Newbery <john@johnnewbery.com>2017-03-20 10:40:31 -0400
commit00902c48cdc5d6a531abfd279fd8e7779cf0a0b8 (patch)
tree41891484a478a7478937fe4a12b63e6c7f31799a /test/rpc-tests/replace-by-fee.py
parentd34995a7bac6ed20ce42aa00c6252b900786e649 (diff)
Rename qa directory to test
Diffstat (limited to 'test/rpc-tests/replace-by-fee.py')
-rwxr-xr-xtest/rpc-tests/replace-by-fee.py525
1 files changed, 525 insertions, 0 deletions
diff --git a/test/rpc-tests/replace-by-fee.py b/test/rpc-tests/replace-by-fee.py
new file mode 100755
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+++ b/test/rpc-tests/replace-by-fee.py
@@ -0,0 +1,525 @@
+#!/usr/bin/env python3
+# Copyright (c) 2014-2016 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 the RBF code."""
+
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import *
+from test_framework.script import *
+from test_framework.mininode import *
+
+MAX_REPLACEMENT_LIMIT = 100
+
+def txToHex(tx):
+ return bytes_to_hex_str(tx.serialize())
+
+def make_utxo(node, amount, confirmed=True, scriptPubKey=CScript([1])):
+ """Create a txout with a given amount and scriptPubKey
+
+ Mines coins as needed.
+
+ confirmed - txouts created will be confirmed in the blockchain;
+ unconfirmed otherwise.
+ """
+ fee = 1*COIN
+ while node.getbalance() < satoshi_round((amount + fee)/COIN):
+ node.generate(100)
+
+ new_addr = node.getnewaddress()
+ txid = node.sendtoaddress(new_addr, satoshi_round((amount+fee)/COIN))
+ tx1 = node.getrawtransaction(txid, 1)
+ txid = int(txid, 16)
+ i = None
+
+ for i, txout in enumerate(tx1['vout']):
+ if txout['scriptPubKey']['addresses'] == [new_addr]:
+ break
+ assert i is not None
+
+ tx2 = CTransaction()
+ tx2.vin = [CTxIn(COutPoint(txid, i))]
+ tx2.vout = [CTxOut(amount, scriptPubKey)]
+ tx2.rehash()
+
+ signed_tx = node.signrawtransaction(txToHex(tx2))
+
+ txid = node.sendrawtransaction(signed_tx['hex'], True)
+
+ # If requested, ensure txouts are confirmed.
+ if confirmed:
+ mempool_size = len(node.getrawmempool())
+ while mempool_size > 0:
+ node.generate(1)
+ new_size = len(node.getrawmempool())
+ # Error out if we have something stuck in the mempool, as this
+ # would likely be a bug.
+ assert(new_size < mempool_size)
+ mempool_size = new_size
+
+ return COutPoint(int(txid, 16), 0)
+
+class ReplaceByFeeTest(BitcoinTestFramework):
+
+ def __init__(self):
+ super().__init__()
+ self.num_nodes = 1
+ self.setup_clean_chain = False
+
+ def setup_network(self):
+ self.nodes = []
+ self.nodes.append(start_node(0, self.options.tmpdir, ["-maxorphantx=1000",
+ "-whitelist=127.0.0.1",
+ "-limitancestorcount=50",
+ "-limitancestorsize=101",
+ "-limitdescendantcount=200",
+ "-limitdescendantsize=101"
+ ]))
+ self.is_network_split = False
+
+ def run_test(self):
+ make_utxo(self.nodes[0], 1*COIN)
+
+ self.log.info("Running test simple doublespend...")
+ self.test_simple_doublespend()
+
+ self.log.info("Running test doublespend chain...")
+ self.test_doublespend_chain()
+
+ self.log.info("Running test doublespend tree...")
+ self.test_doublespend_tree()
+
+ self.log.info("Running test replacement feeperkb...")
+ self.test_replacement_feeperkb()
+
+ self.log.info("Running test spends of conflicting outputs...")
+ self.test_spends_of_conflicting_outputs()
+
+ self.log.info("Running test new unconfirmed inputs...")
+ self.test_new_unconfirmed_inputs()
+
+ self.log.info("Running test too many replacements...")
+ self.test_too_many_replacements()
+
+ self.log.info("Running test opt-in...")
+ self.test_opt_in()
+
+ self.log.info("Running test prioritised transactions...")
+ self.test_prioritised_transactions()
+
+ self.log.info("Passed")
+
+ def test_simple_doublespend(self):
+ """Simple doublespend"""
+ tx0_outpoint = make_utxo(self.nodes[0], int(1.1*COIN))
+
+ tx1a = CTransaction()
+ tx1a.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1a.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx1a_hex = txToHex(tx1a)
+ tx1a_txid = self.nodes[0].sendrawtransaction(tx1a_hex, True)
+
+ # Should fail because we haven't changed the fee
+ tx1b = CTransaction()
+ tx1b.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1b.vout = [CTxOut(1*COIN, CScript([b'b']))]
+ tx1b_hex = txToHex(tx1b)
+
+ # This will raise an exception due to insufficient fee
+ assert_raises_jsonrpc(-26, "insufficient fee", self.nodes[0].sendrawtransaction, tx1b_hex, True)
+
+ # Extra 0.1 BTC fee
+ tx1b = CTransaction()
+ tx1b.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1b.vout = [CTxOut(int(0.9*COIN), CScript([b'b']))]
+ tx1b_hex = txToHex(tx1b)
+ tx1b_txid = self.nodes[0].sendrawtransaction(tx1b_hex, True)
+
+ mempool = self.nodes[0].getrawmempool()
+
+ assert (tx1a_txid not in mempool)
+ assert (tx1b_txid in mempool)
+
+ assert_equal(tx1b_hex, self.nodes[0].getrawtransaction(tx1b_txid))
+
+ def test_doublespend_chain(self):
+ """Doublespend of a long chain"""
+
+ initial_nValue = 50*COIN
+ tx0_outpoint = make_utxo(self.nodes[0], initial_nValue)
+
+ prevout = tx0_outpoint
+ remaining_value = initial_nValue
+ chain_txids = []
+ while remaining_value > 10*COIN:
+ remaining_value -= 1*COIN
+ tx = CTransaction()
+ tx.vin = [CTxIn(prevout, nSequence=0)]
+ tx.vout = [CTxOut(remaining_value, CScript([1]))]
+ tx_hex = txToHex(tx)
+ txid = self.nodes[0].sendrawtransaction(tx_hex, True)
+ chain_txids.append(txid)
+ prevout = COutPoint(int(txid, 16), 0)
+
+ # Whether the double-spend is allowed is evaluated by including all
+ # child fees - 40 BTC - so this attempt is rejected.
+ dbl_tx = CTransaction()
+ dbl_tx.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ dbl_tx.vout = [CTxOut(initial_nValue - 30*COIN, CScript([1]))]
+ dbl_tx_hex = txToHex(dbl_tx)
+
+ # This will raise an exception due to insufficient fee
+ assert_raises_jsonrpc(-26, "insufficient fee", self.nodes[0].sendrawtransaction, dbl_tx_hex, True)
+
+ # Accepted with sufficient fee
+ dbl_tx = CTransaction()
+ dbl_tx.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ dbl_tx.vout = [CTxOut(1*COIN, CScript([1]))]
+ dbl_tx_hex = txToHex(dbl_tx)
+ self.nodes[0].sendrawtransaction(dbl_tx_hex, True)
+
+ mempool = self.nodes[0].getrawmempool()
+ for doublespent_txid in chain_txids:
+ assert(doublespent_txid not in mempool)
+
+ def test_doublespend_tree(self):
+ """Doublespend of a big tree of transactions"""
+
+ initial_nValue = 50*COIN
+ tx0_outpoint = make_utxo(self.nodes[0], initial_nValue)
+
+ def branch(prevout, initial_value, max_txs, tree_width=5, fee=0.0001*COIN, _total_txs=None):
+ if _total_txs is None:
+ _total_txs = [0]
+ if _total_txs[0] >= max_txs:
+ return
+
+ txout_value = (initial_value - fee) // tree_width
+ if txout_value < fee:
+ return
+
+ vout = [CTxOut(txout_value, CScript([i+1]))
+ for i in range(tree_width)]
+ tx = CTransaction()
+ tx.vin = [CTxIn(prevout, nSequence=0)]
+ tx.vout = vout
+ tx_hex = txToHex(tx)
+
+ assert(len(tx.serialize()) < 100000)
+ txid = self.nodes[0].sendrawtransaction(tx_hex, True)
+ yield tx
+ _total_txs[0] += 1
+
+ txid = int(txid, 16)
+
+ for i, txout in enumerate(tx.vout):
+ for x in branch(COutPoint(txid, i), txout_value,
+ max_txs,
+ tree_width=tree_width, fee=fee,
+ _total_txs=_total_txs):
+ yield x
+
+ fee = int(0.0001*COIN)
+ n = MAX_REPLACEMENT_LIMIT
+ tree_txs = list(branch(tx0_outpoint, initial_nValue, n, fee=fee))
+ assert_equal(len(tree_txs), n)
+
+ # Attempt double-spend, will fail because too little fee paid
+ dbl_tx = CTransaction()
+ dbl_tx.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ dbl_tx.vout = [CTxOut(initial_nValue - fee*n, CScript([1]))]
+ dbl_tx_hex = txToHex(dbl_tx)
+ # This will raise an exception due to insufficient fee
+ assert_raises_jsonrpc(-26, "insufficient fee", self.nodes[0].sendrawtransaction, dbl_tx_hex, True)
+
+ # 1 BTC fee is enough
+ dbl_tx = CTransaction()
+ dbl_tx.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ dbl_tx.vout = [CTxOut(initial_nValue - fee*n - 1*COIN, CScript([1]))]
+ dbl_tx_hex = txToHex(dbl_tx)
+ self.nodes[0].sendrawtransaction(dbl_tx_hex, True)
+
+ mempool = self.nodes[0].getrawmempool()
+
+ for tx in tree_txs:
+ tx.rehash()
+ assert (tx.hash not in mempool)
+
+ # Try again, but with more total transactions than the "max txs
+ # double-spent at once" anti-DoS limit.
+ for n in (MAX_REPLACEMENT_LIMIT+1, MAX_REPLACEMENT_LIMIT*2):
+ fee = int(0.0001*COIN)
+ tx0_outpoint = make_utxo(self.nodes[0], initial_nValue)
+ tree_txs = list(branch(tx0_outpoint, initial_nValue, n, fee=fee))
+ assert_equal(len(tree_txs), n)
+
+ dbl_tx = CTransaction()
+ dbl_tx.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ dbl_tx.vout = [CTxOut(initial_nValue - 2*fee*n, CScript([1]))]
+ dbl_tx_hex = txToHex(dbl_tx)
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "too many potential replacements", self.nodes[0].sendrawtransaction, dbl_tx_hex, True)
+
+ for tx in tree_txs:
+ tx.rehash()
+ self.nodes[0].getrawtransaction(tx.hash)
+
+ def test_replacement_feeperkb(self):
+ """Replacement requires fee-per-KB to be higher"""
+ tx0_outpoint = make_utxo(self.nodes[0], int(1.1*COIN))
+
+ tx1a = CTransaction()
+ tx1a.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1a.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx1a_hex = txToHex(tx1a)
+ tx1a_txid = self.nodes[0].sendrawtransaction(tx1a_hex, True)
+
+ # Higher fee, but the fee per KB is much lower, so the replacement is
+ # rejected.
+ tx1b = CTransaction()
+ tx1b.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1b.vout = [CTxOut(int(0.001*COIN), CScript([b'a'*999000]))]
+ tx1b_hex = txToHex(tx1b)
+
+ # This will raise an exception due to insufficient fee
+ assert_raises_jsonrpc(-26, "insufficient fee", self.nodes[0].sendrawtransaction, tx1b_hex, True)
+
+ def test_spends_of_conflicting_outputs(self):
+ """Replacements that spend conflicting tx outputs are rejected"""
+ utxo1 = make_utxo(self.nodes[0], int(1.2*COIN))
+ utxo2 = make_utxo(self.nodes[0], 3*COIN)
+
+ tx1a = CTransaction()
+ tx1a.vin = [CTxIn(utxo1, nSequence=0)]
+ tx1a.vout = [CTxOut(int(1.1*COIN), CScript([b'a']))]
+ tx1a_hex = txToHex(tx1a)
+ tx1a_txid = self.nodes[0].sendrawtransaction(tx1a_hex, True)
+
+ tx1a_txid = int(tx1a_txid, 16)
+
+ # Direct spend an output of the transaction we're replacing.
+ tx2 = CTransaction()
+ tx2.vin = [CTxIn(utxo1, nSequence=0), CTxIn(utxo2, nSequence=0)]
+ tx2.vin.append(CTxIn(COutPoint(tx1a_txid, 0), nSequence=0))
+ tx2.vout = tx1a.vout
+ tx2_hex = txToHex(tx2)
+
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "bad-txns-spends-conflicting-tx", self.nodes[0].sendrawtransaction, tx2_hex, True)
+
+ # Spend tx1a's output to test the indirect case.
+ tx1b = CTransaction()
+ tx1b.vin = [CTxIn(COutPoint(tx1a_txid, 0), nSequence=0)]
+ tx1b.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx1b_hex = txToHex(tx1b)
+ tx1b_txid = self.nodes[0].sendrawtransaction(tx1b_hex, True)
+ tx1b_txid = int(tx1b_txid, 16)
+
+ tx2 = CTransaction()
+ tx2.vin = [CTxIn(utxo1, nSequence=0), CTxIn(utxo2, nSequence=0),
+ CTxIn(COutPoint(tx1b_txid, 0))]
+ tx2.vout = tx1a.vout
+ tx2_hex = txToHex(tx2)
+
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "bad-txns-spends-conflicting-tx", self.nodes[0].sendrawtransaction, tx2_hex, True)
+
+ def test_new_unconfirmed_inputs(self):
+ """Replacements that add new unconfirmed inputs are rejected"""
+ confirmed_utxo = make_utxo(self.nodes[0], int(1.1*COIN))
+ unconfirmed_utxo = make_utxo(self.nodes[0], int(0.1*COIN), False)
+
+ tx1 = CTransaction()
+ tx1.vin = [CTxIn(confirmed_utxo)]
+ tx1.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx1_hex = txToHex(tx1)
+ tx1_txid = self.nodes[0].sendrawtransaction(tx1_hex, True)
+
+ tx2 = CTransaction()
+ tx2.vin = [CTxIn(confirmed_utxo), CTxIn(unconfirmed_utxo)]
+ tx2.vout = tx1.vout
+ tx2_hex = txToHex(tx2)
+
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "replacement-adds-unconfirmed", self.nodes[0].sendrawtransaction, tx2_hex, True)
+
+ def test_too_many_replacements(self):
+ """Replacements that evict too many transactions are rejected"""
+ # Try directly replacing more than MAX_REPLACEMENT_LIMIT
+ # transactions
+
+ # Start by creating a single transaction with many outputs
+ initial_nValue = 10*COIN
+ utxo = make_utxo(self.nodes[0], initial_nValue)
+ fee = int(0.0001*COIN)
+ split_value = int((initial_nValue-fee)/(MAX_REPLACEMENT_LIMIT+1))
+
+ outputs = []
+ for i in range(MAX_REPLACEMENT_LIMIT+1):
+ outputs.append(CTxOut(split_value, CScript([1])))
+
+ splitting_tx = CTransaction()
+ splitting_tx.vin = [CTxIn(utxo, nSequence=0)]
+ splitting_tx.vout = outputs
+ splitting_tx_hex = txToHex(splitting_tx)
+
+ txid = self.nodes[0].sendrawtransaction(splitting_tx_hex, True)
+ txid = int(txid, 16)
+
+ # Now spend each of those outputs individually
+ for i in range(MAX_REPLACEMENT_LIMIT+1):
+ tx_i = CTransaction()
+ tx_i.vin = [CTxIn(COutPoint(txid, i), nSequence=0)]
+ tx_i.vout = [CTxOut(split_value-fee, CScript([b'a']))]
+ tx_i_hex = txToHex(tx_i)
+ self.nodes[0].sendrawtransaction(tx_i_hex, True)
+
+ # Now create doublespend of the whole lot; should fail.
+ # Need a big enough fee to cover all spending transactions and have
+ # a higher fee rate
+ double_spend_value = (split_value-100*fee)*(MAX_REPLACEMENT_LIMIT+1)
+ inputs = []
+ for i in range(MAX_REPLACEMENT_LIMIT+1):
+ inputs.append(CTxIn(COutPoint(txid, i), nSequence=0))
+ double_tx = CTransaction()
+ double_tx.vin = inputs
+ double_tx.vout = [CTxOut(double_spend_value, CScript([b'a']))]
+ double_tx_hex = txToHex(double_tx)
+
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "too many potential replacements", self.nodes[0].sendrawtransaction, double_tx_hex, True)
+
+ # If we remove an input, it should pass
+ double_tx = CTransaction()
+ double_tx.vin = inputs[0:-1]
+ double_tx.vout = [CTxOut(double_spend_value, CScript([b'a']))]
+ double_tx_hex = txToHex(double_tx)
+ self.nodes[0].sendrawtransaction(double_tx_hex, True)
+
+ def test_opt_in(self):
+ """Replacing should only work if orig tx opted in"""
+ tx0_outpoint = make_utxo(self.nodes[0], int(1.1*COIN))
+
+ # Create a non-opting in transaction
+ tx1a = CTransaction()
+ tx1a.vin = [CTxIn(tx0_outpoint, nSequence=0xffffffff)]
+ tx1a.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx1a_hex = txToHex(tx1a)
+ tx1a_txid = self.nodes[0].sendrawtransaction(tx1a_hex, True)
+
+ # Shouldn't be able to double-spend
+ tx1b = CTransaction()
+ tx1b.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1b.vout = [CTxOut(int(0.9*COIN), CScript([b'b']))]
+ tx1b_hex = txToHex(tx1b)
+
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "txn-mempool-conflict", self.nodes[0].sendrawtransaction, tx1b_hex, True)
+
+ tx1_outpoint = make_utxo(self.nodes[0], int(1.1*COIN))
+
+ # Create a different non-opting in transaction
+ tx2a = CTransaction()
+ tx2a.vin = [CTxIn(tx1_outpoint, nSequence=0xfffffffe)]
+ tx2a.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx2a_hex = txToHex(tx2a)
+ tx2a_txid = self.nodes[0].sendrawtransaction(tx2a_hex, True)
+
+ # Still shouldn't be able to double-spend
+ tx2b = CTransaction()
+ tx2b.vin = [CTxIn(tx1_outpoint, nSequence=0)]
+ tx2b.vout = [CTxOut(int(0.9*COIN), CScript([b'b']))]
+ tx2b_hex = txToHex(tx2b)
+
+ # This will raise an exception
+ assert_raises_jsonrpc(-26, "txn-mempool-conflict", self.nodes[0].sendrawtransaction, tx2b_hex, True)
+
+ # Now create a new transaction that spends from tx1a and tx2a
+ # opt-in on one of the inputs
+ # Transaction should be replaceable on either input
+
+ tx1a_txid = int(tx1a_txid, 16)
+ tx2a_txid = int(tx2a_txid, 16)
+
+ tx3a = CTransaction()
+ tx3a.vin = [CTxIn(COutPoint(tx1a_txid, 0), nSequence=0xffffffff),
+ CTxIn(COutPoint(tx2a_txid, 0), nSequence=0xfffffffd)]
+ tx3a.vout = [CTxOut(int(0.9*COIN), CScript([b'c'])), CTxOut(int(0.9*COIN), CScript([b'd']))]
+ tx3a_hex = txToHex(tx3a)
+
+ self.nodes[0].sendrawtransaction(tx3a_hex, True)
+
+ tx3b = CTransaction()
+ tx3b.vin = [CTxIn(COutPoint(tx1a_txid, 0), nSequence=0)]
+ tx3b.vout = [CTxOut(int(0.5*COIN), CScript([b'e']))]
+ tx3b_hex = txToHex(tx3b)
+
+ tx3c = CTransaction()
+ tx3c.vin = [CTxIn(COutPoint(tx2a_txid, 0), nSequence=0)]
+ tx3c.vout = [CTxOut(int(0.5*COIN), CScript([b'f']))]
+ tx3c_hex = txToHex(tx3c)
+
+ self.nodes[0].sendrawtransaction(tx3b_hex, True)
+ # If tx3b was accepted, tx3c won't look like a replacement,
+ # but make sure it is accepted anyway
+ self.nodes[0].sendrawtransaction(tx3c_hex, True)
+
+ def test_prioritised_transactions(self):
+ # Ensure that fee deltas used via prioritisetransaction are
+ # correctly used by replacement logic
+
+ # 1. Check that feeperkb uses modified fees
+ tx0_outpoint = make_utxo(self.nodes[0], int(1.1*COIN))
+
+ tx1a = CTransaction()
+ tx1a.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1a.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx1a_hex = txToHex(tx1a)
+ tx1a_txid = self.nodes[0].sendrawtransaction(tx1a_hex, True)
+
+ # Higher fee, but the actual fee per KB is much lower.
+ tx1b = CTransaction()
+ tx1b.vin = [CTxIn(tx0_outpoint, nSequence=0)]
+ tx1b.vout = [CTxOut(int(0.001*COIN), CScript([b'a'*740000]))]
+ tx1b_hex = txToHex(tx1b)
+
+ # Verify tx1b cannot replace tx1a.
+ assert_raises_jsonrpc(-26, "insufficient fee", self.nodes[0].sendrawtransaction, tx1b_hex, True)
+
+ # Use prioritisetransaction to set tx1a's fee to 0.
+ self.nodes[0].prioritisetransaction(tx1a_txid, int(-0.1*COIN))
+
+ # Now tx1b should be able to replace tx1a
+ tx1b_txid = self.nodes[0].sendrawtransaction(tx1b_hex, True)
+
+ assert(tx1b_txid in self.nodes[0].getrawmempool())
+
+ # 2. Check that absolute fee checks use modified fee.
+ tx1_outpoint = make_utxo(self.nodes[0], int(1.1*COIN))
+
+ tx2a = CTransaction()
+ tx2a.vin = [CTxIn(tx1_outpoint, nSequence=0)]
+ tx2a.vout = [CTxOut(1*COIN, CScript([b'a']))]
+ tx2a_hex = txToHex(tx2a)
+ tx2a_txid = self.nodes[0].sendrawtransaction(tx2a_hex, True)
+
+ # Lower fee, but we'll prioritise it
+ tx2b = CTransaction()
+ tx2b.vin = [CTxIn(tx1_outpoint, nSequence=0)]
+ tx2b.vout = [CTxOut(int(1.01*COIN), CScript([b'a']))]
+ tx2b.rehash()
+ tx2b_hex = txToHex(tx2b)
+
+ # Verify tx2b cannot replace tx2a.
+ assert_raises_jsonrpc(-26, "insufficient fee", self.nodes[0].sendrawtransaction, tx2b_hex, True)
+
+ # Now prioritise tx2b to have a higher modified fee
+ self.nodes[0].prioritisetransaction(tx2b.hash, int(0.1*COIN))
+
+ # tx2b should now be accepted
+ tx2b_txid = self.nodes[0].sendrawtransaction(tx2b_hex, True)
+
+ assert(tx2b_txid in self.nodes[0].getrawmempool())
+
+if __name__ == '__main__':
+ ReplaceByFeeTest().main()