Repository: bitcoin/bitcoin
File: test/functional/mempool_package_rbf.py (Python)

Code before:
        assert_equal(submitres["replaced-transactions"], [singleton_tx["tx"].rehash()])
        self.assert_mempool_contents(expected=package_txns)

        self.generate(node, 1)

    def test_package_rbf_additional_fees(self):
        self.log.info("Check Package RBF must increase the absolute fee")
        node = self.nodes[0]
        coin = self.coins.pop()

        package_hex1, package_txns1 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE, heavy_child=True)
        assert_greater_than_or_equal(1000, package_txns1[-1].get_vsize())
        node.submitpackage(package_hex1)
        self.assert_mempool_contents(expected=package_txns1)

        PACKAGE_FEE = DEFAULT_FEE + DEFAULT_CHILD_FEE
        PACKAGE_FEE_MINUS_ONE = PACKAGE_FEE - Decimal("0.00000001")

        # Package 2 has a higher feerate but lower absolute fee
        package_hex2, package_txns2 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE - Decimal("0.00000001"))
        pkg_results2 = node.submitpackage(package_hex2)
        assert_equal(f"package RBF failed: insufficient anti-DoS fees, rejecting replacement {package_txns2[1].rehash()}, less fees than conflicting txs; {PACKAGE_FEE_MINUS_ONE} < {PACKAGE_FEE}", pkg_results2["package_msg"])
        self.assert_mempool_contents(expected=package_txns1)

        self.log.info("Check replacement pays for incremental bandwidth")
        package_hex3, package_txns3 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE)
        pkg_results3 = node.submitpackage(package_hex3)
        assert_equal(f"package RBF failed: insufficient anti-DoS fees, rejecting replacement {package_txns3[1].rehash()}, not enough additional fees to relay; 0.00 < 0.00000{sum([tx.get_vsize() for tx in package_txns3])}", pkg_results3["package_msg"])

        self.assert_mempool_contents(expected=package_txns1)
        self.generate(node, 1)

        self.log.info("Check Package RBF must have strict cpfp structure")
        coin = self.coins.pop()
        package_hex4, package_txns4 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE)
        node.submitpackage(package_hex4)
        self.assert_mempool_contents(expected=package_txns4)
        package_hex5, package_txns5 = self.create_simple_package(coin, parent_fee=DEFAULT_CHILD_FEE, child_fee=DEFAULT_CHILD_FEE - Decimal("0.00000001"))
        pkg_results5 = node.submitpackage(package_hex5)
        assert 'package RBF failed: package feerate is less than parent feerate' in pkg_results5["package_msg"]

        self.assert_mempool_contents(expected=package_txns4)
        self.generate(node, 1)

    def test_package_rbf_max_conflicts(self):
        node = self.nodes[0]
        self.log.info("Check Package RBF cannot replace more than MAX_REPLACEMENT_CANDIDATES transactions")
        num_coins = 51
        parent_coins = self.coins[:num_coins]
        del self.coins[:num_coins]


Review comment (suggestion):
Renaming would help distinguish the variables which are currently reassigned later. Also, since fee doesn't matter.

```suggestion
        _, placeholder_txns3 = self.create_simple_package(coin)
```

Code after:
        assert_equal(submitres["replaced-transactions"], [singleton_tx["tx"].rehash()])
        self.assert_mempool_contents(expected=package_txns)

        self.generate(node, 1)

    def test_package_rbf_additional_fees(self):
        self.log.info("Check Package RBF must increase the absolute fee")
        node = self.nodes[0]
        coin = self.coins.pop()

        package_hex1, package_txns1 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE, heavy_child=True)
        assert_greater_than_or_equal(1000, package_txns1[-1].get_vsize())
        node.submitpackage(package_hex1)
        self.assert_mempool_contents(expected=package_txns1)

        PACKAGE_FEE = DEFAULT_FEE + DEFAULT_CHILD_FEE
        PACKAGE_FEE_MINUS_ONE = PACKAGE_FEE - Decimal("0.00000001")

        # Package 2 has a higher feerate but lower absolute fee
        package_hex2, package_txns2 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE - Decimal("0.00000001"))
        pkg_results2 = node.submitpackage(package_hex2)
        assert_equal(f"package RBF failed: insufficient anti-DoS fees, rejecting replacement {package_txns2[1].rehash()}, less fees than conflicting txs; {PACKAGE_FEE_MINUS_ONE} < {PACKAGE_FEE}", pkg_results2["package_msg"])
        self.assert_mempool_contents(expected=package_txns1)

        self.log.info("Check replacement pays for incremental bandwidth")
        _, placeholder_txns3 = self.create_simple_package(coin)
        package_3_size = sum([tx.get_vsize() for tx in placeholder_txns3])
        incremental_sats_required = Decimal(package_3_size) / COIN
        incremental_sats_short = incremental_sats_required - Decimal("0.00000001")
        # Recreate the package with slightly higher fee once we know the size of the new package, but still short of required fee
        failure_package_hex3, failure_package_txns3 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE + incremental_sats_short)
        assert_equal(package_3_size, sum([tx.get_vsize() for tx in failure_package_txns3]))
        pkg_results3 = node.submitpackage(failure_package_hex3)
        assert_equal(f"package RBF failed: insufficient anti-DoS fees, rejecting replacement {failure_package_txns3[1].rehash()}, not enough additional fees to relay; {incremental_sats_short} < {incremental_sats_required}", pkg_results3["package_msg"])
        self.assert_mempool_contents(expected=package_txns1)

        success_package_hex3, success_package_txns3 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE + incremental_sats_required)
        node.submitpackage(success_package_hex3)
        self.assert_mempool_contents(expected=success_package_txns3)
        self.generate(node, 1)

        self.log.info("Check Package RBF must have strict cpfp structure")
        coin = self.coins.pop()
        package_hex4, package_txns4 = self.create_simple_package(coin, parent_fee=DEFAULT_FEE, child_fee=DEFAULT_CHILD_FEE)
        node.submitpackage(package_hex4)
        self.assert_mempool_contents(expected=package_txns4)
        package_hex5, package_txns5 = self.create_simple_package(coin, parent_fee=DEFAULT_CHILD_FEE, child_fee=DEFAULT_CHILD_FEE)
        pkg_results5 = node.submitpackage(package_hex5)
        assert 'package RBF failed: package feerate is less than or equal to parent feerate' in pkg_results5["package_msg"]
        self.assert_mempool_contents(expected=package_txns4)