/ src / test / rbf_tests.cpp
rbf_tests.cpp
  1  // Copyright (c) 2021-2022 The Bitcoin Core developers
  2  // Distributed under the MIT software license, see the accompanying
  3  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  4  #include <common/system.h>
  5  #include <policy/rbf.h>
  6  #include <random.h>
  7  #include <test/util/txmempool.h>
  8  #include <txmempool.h>
  9  #include <util/time.h>
 10  
 11  #include <test/util/setup_common.h>
 12  
 13  #include <boost/test/unit_test.hpp>
 14  #include <optional>
 15  #include <vector>
 16  
 17  BOOST_FIXTURE_TEST_SUITE(rbf_tests, TestingSetup)
 18  
 19  static inline CTransactionRef make_tx(const std::vector<CTransactionRef>& inputs,
 20                                        const std::vector<CAmount>& output_values)
 21  {
 22      CMutableTransaction tx = CMutableTransaction();
 23      tx.vin.resize(inputs.size());
 24      tx.vout.resize(output_values.size());
 25      for (size_t i = 0; i < inputs.size(); ++i) {
 26          tx.vin[i].prevout.hash = inputs[i]->GetHash();
 27          tx.vin[i].prevout.n = 0;
 28          // Add a witness so wtxid != txid
 29          CScriptWitness witness;
 30          witness.stack.emplace_back(i + 10);
 31          tx.vin[i].scriptWitness = witness;
 32      }
 33      for (size_t i = 0; i < output_values.size(); ++i) {
 34          tx.vout[i].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 35          tx.vout[i].nValue = output_values[i];
 36      }
 37      return MakeTransactionRef(tx);
 38  }
 39  
 40  // Make two child transactions from parent (which must have at least 2 outputs).
 41  // Each tx will have the same outputs, using the amounts specified in output_values.
 42  static inline std::pair<CTransactionRef, CTransactionRef> make_two_siblings(const CTransactionRef parent,
 43                                        const std::vector<CAmount>& output_values)
 44  {
 45      assert(parent->vout.size() >= 2);
 46  
 47      // First tx takes first parent output
 48      CMutableTransaction tx1 = CMutableTransaction();
 49      tx1.vin.resize(1);
 50      tx1.vout.resize(output_values.size());
 51  
 52      tx1.vin[0].prevout.hash = parent->GetHash();
 53      tx1.vin[0].prevout.n = 0;
 54      // Add a witness so wtxid != txid
 55      CScriptWitness witness;
 56      witness.stack.emplace_back(10);
 57      tx1.vin[0].scriptWitness = witness;
 58  
 59      for (size_t i = 0; i < output_values.size(); ++i) {
 60          tx1.vout[i].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 61          tx1.vout[i].nValue = output_values[i];
 62      }
 63  
 64      // Second tx takes second parent output
 65      CMutableTransaction tx2 = tx1;
 66      tx2.vin[0].prevout.n = 1;
 67  
 68      return std::make_pair(MakeTransactionRef(tx1), MakeTransactionRef(tx2));
 69  }
 70  
 71  static CTransactionRef add_descendants(const CTransactionRef& tx, int32_t num_descendants, CTxMemPool& pool)
 72      EXCLUSIVE_LOCKS_REQUIRED(::cs_main, pool.cs)
 73  {
 74      AssertLockHeld(::cs_main);
 75      AssertLockHeld(pool.cs);
 76      TestMemPoolEntryHelper entry;
 77      // Assumes this isn't already spent in mempool
 78      auto tx_to_spend = tx;
 79      for (int32_t i{0}; i < num_descendants; ++i) {
 80          auto next_tx = make_tx(/*inputs=*/{tx_to_spend}, /*output_values=*/{(50 - i) * CENT});
 81          AddToMempool(pool, entry.FromTx(next_tx));
 82          tx_to_spend = next_tx;
 83      }
 84      // Return last created tx
 85      return tx_to_spend;
 86  }
 87  
 88  static CTransactionRef add_descendant_to_parents(const std::vector<CTransactionRef>& parents, CTxMemPool& pool)
 89      EXCLUSIVE_LOCKS_REQUIRED(::cs_main, pool.cs)
 90  {
 91      AssertLockHeld(::cs_main);
 92      AssertLockHeld(pool.cs);
 93      TestMemPoolEntryHelper entry;
 94      // Assumes this isn't already spent in mempool
 95      auto child_tx = make_tx(/*inputs=*/parents, /*output_values=*/{50 * CENT});
 96      AddToMempool(pool, entry.FromTx(child_tx));
 97      // Return last created tx
 98      return child_tx;
 99  }
100  
101  // Makes two children for a single parent
102  static std::pair<CTransactionRef, CTransactionRef> add_children_to_parent(const CTransactionRef parent, CTxMemPool& pool)
103      EXCLUSIVE_LOCKS_REQUIRED(::cs_main, pool.cs)
104  {
105      AssertLockHeld(::cs_main);
106      AssertLockHeld(pool.cs);
107      TestMemPoolEntryHelper entry;
108      // Assumes this isn't already spent in mempool
109      auto children_tx = make_two_siblings(/*parent=*/parent, /*output_values=*/{50 * CENT});
110      AddToMempool(pool, entry.FromTx(children_tx.first));
111      AddToMempool(pool, entry.FromTx(children_tx.second));
112      return children_tx;
113  }
114  
115  BOOST_FIXTURE_TEST_CASE(rbf_helper_functions, TestChain100Setup)
116  {
117      CTxMemPool& pool = *Assert(m_node.mempool);
118      LOCK2(::cs_main, pool.cs);
119      TestMemPoolEntryHelper entry;
120  
121      const CAmount low_fee{CENT/100};
122      const CAmount normal_fee{CENT/10};
123      const CAmount high_fee{CENT};
124  
125      // Create a parent tx1 and child tx2 with normal fees:
126      const auto tx1 = make_tx(/*inputs=*/ {m_coinbase_txns[0]}, /*output_values=*/ {10 * COIN});
127      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx1));
128      const auto tx2 = make_tx(/*inputs=*/ {tx1}, /*output_values=*/ {995 * CENT});
129      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx2));
130  
131      // Create a low-feerate parent tx3 and high-feerate child tx4 (cpfp)
132      const auto tx3 = make_tx(/*inputs=*/ {m_coinbase_txns[1]}, /*output_values=*/ {1099 * CENT});
133      AddToMempool(pool, entry.Fee(low_fee).FromTx(tx3));
134      const auto tx4 = make_tx(/*inputs=*/ {tx3}, /*output_values=*/ {999 * CENT});
135      AddToMempool(pool, entry.Fee(high_fee).FromTx(tx4));
136  
137      // Create a parent tx5 and child tx6 where both have very low fees
138      const auto tx5 = make_tx(/*inputs=*/ {m_coinbase_txns[2]}, /*output_values=*/ {1099 * CENT});
139      AddToMempool(pool, entry.Fee(low_fee).FromTx(tx5));
140      const auto tx6 = make_tx(/*inputs=*/ {tx5}, /*output_values=*/ {1098 * CENT});
141      AddToMempool(pool, entry.Fee(low_fee).FromTx(tx6));
142      // Make tx6's modified fee much higher than its base fee. This should cause it to pass
143      // the fee-related checks despite being low-feerate.
144      pool.PrioritiseTransaction(tx6->GetHash(), 1 * COIN);
145  
146      // Two independent high-feerate transactions, tx7 and tx8
147      const auto tx7 = make_tx(/*inputs=*/ {m_coinbase_txns[3]}, /*output_values=*/ {999 * CENT});
148      AddToMempool(pool, entry.Fee(high_fee).FromTx(tx7));
149      const auto tx8 = make_tx(/*inputs=*/ {m_coinbase_txns[4]}, /*output_values=*/ {999 * CENT});
150      AddToMempool(pool, entry.Fee(high_fee).FromTx(tx8));
151  
152      // Normal txs, will chain txns right before CheckConflictTopology test
153      const auto tx9 = make_tx(/*inputs=*/ {m_coinbase_txns[5]}, /*output_values=*/ {995 * CENT});
154      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx9));
155      const auto tx10 = make_tx(/*inputs=*/ {m_coinbase_txns[6]}, /*output_values=*/ {995 * CENT});
156      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx10));
157  
158      // Will make these two parents of single child
159      const auto tx11 = make_tx(/*inputs=*/ {m_coinbase_txns[7]}, /*output_values=*/ {995 * CENT});
160      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx11));
161      const auto tx12 = make_tx(/*inputs=*/ {m_coinbase_txns[8]}, /*output_values=*/ {995 * CENT});
162      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx12));
163  
164      // Will make two children of this single parent
165      const auto tx13 = make_tx(/*inputs=*/ {m_coinbase_txns[9]}, /*output_values=*/ {995 * CENT, 995 * CENT});
166      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx13));
167  
168      const auto entry1_normal = pool.GetIter(tx1->GetHash()).value();
169      const auto entry2_normal = pool.GetIter(tx2->GetHash()).value();
170      const auto entry3_low = pool.GetIter(tx3->GetHash()).value();
171      const auto entry4_high = pool.GetIter(tx4->GetHash()).value();
172      const auto entry5_low = pool.GetIter(tx5->GetHash()).value();
173      const auto entry6_low_prioritised = pool.GetIter(tx6->GetHash()).value();
174      const auto entry7_high = pool.GetIter(tx7->GetHash()).value();
175      const auto entry8_high = pool.GetIter(tx8->GetHash()).value();
176      const auto entry9_unchained = pool.GetIter(tx9->GetHash()).value();
177      const auto entry10_unchained = pool.GetIter(tx10->GetHash()).value();
178      const auto entry11_unchained = pool.GetIter(tx11->GetHash()).value();
179      const auto entry12_unchained = pool.GetIter(tx12->GetHash()).value();
180      const auto entry13_unchained = pool.GetIter(tx13->GetHash()).value();
181  
182      BOOST_CHECK_EQUAL(entry1_normal->GetFee(), normal_fee);
183      BOOST_CHECK_EQUAL(entry2_normal->GetFee(), normal_fee);
184      BOOST_CHECK_EQUAL(entry3_low->GetFee(), low_fee);
185      BOOST_CHECK_EQUAL(entry4_high->GetFee(), high_fee);
186      BOOST_CHECK_EQUAL(entry5_low->GetFee(), low_fee);
187      BOOST_CHECK_EQUAL(entry6_low_prioritised->GetFee(), low_fee);
188      BOOST_CHECK_EQUAL(entry7_high->GetFee(), high_fee);
189      BOOST_CHECK_EQUAL(entry8_high->GetFee(), high_fee);
190  
191      CTxMemPool::setEntries set_12_normal{entry1_normal, entry2_normal};
192      CTxMemPool::setEntries set_34_cpfp{entry3_low, entry4_high};
193      CTxMemPool::setEntries set_56_low{entry5_low, entry6_low_prioritised};
194      CTxMemPool::setEntries set_78_high{entry7_high, entry8_high};
195      CTxMemPool::setEntries all_entries{entry1_normal, entry2_normal, entry3_low, entry4_high,
196                                         entry5_low, entry6_low_prioritised, entry7_high, entry8_high};
197      CTxMemPool::setEntries empty_set;
198  
199      const auto unused_txid{GetRandHash()};
200  
201      // Tests for PaysMoreThanConflicts
202      // These tests use feerate, not absolute fee.
203      BOOST_CHECK(PaysMoreThanConflicts(/*iters_conflicting=*/set_12_normal,
204                                        /*replacement_feerate=*/CFeeRate(entry1_normal->GetModifiedFee() + 1, entry1_normal->GetTxSize() + 2),
205                                        /*txid=*/unused_txid).has_value());
206      // Replacement must be strictly greater than the originals.
207      BOOST_CHECK(PaysMoreThanConflicts(set_12_normal, CFeeRate(entry1_normal->GetModifiedFee(), entry1_normal->GetTxSize()), unused_txid).has_value());
208      BOOST_CHECK(PaysMoreThanConflicts(set_12_normal, CFeeRate(entry1_normal->GetModifiedFee() + 1, entry1_normal->GetTxSize()), unused_txid) == std::nullopt);
209      // These tests use modified fees (including prioritisation), not base fees.
210      BOOST_CHECK(PaysMoreThanConflicts({entry5_low}, CFeeRate(entry5_low->GetModifiedFee() + 1, entry5_low->GetTxSize()), unused_txid) == std::nullopt);
211      BOOST_CHECK(PaysMoreThanConflicts({entry6_low_prioritised}, CFeeRate(entry6_low_prioritised->GetFee() + 1, entry6_low_prioritised->GetTxSize()), unused_txid).has_value());
212      BOOST_CHECK(PaysMoreThanConflicts({entry6_low_prioritised}, CFeeRate(entry6_low_prioritised->GetModifiedFee() + 1, entry6_low_prioritised->GetTxSize()), unused_txid) == std::nullopt);
213      // PaysMoreThanConflicts checks individual feerate, not ancestor feerate. This test compares
214      // replacement_feerate and entry4_high's feerate, which are the same. The replacement_feerate is
215      // considered too low even though entry4_high has a low ancestor feerate.
216      BOOST_CHECK(PaysMoreThanConflicts(set_34_cpfp, CFeeRate(entry4_high->GetModifiedFee(), entry4_high->GetTxSize()), unused_txid).has_value());
217  
218      // Tests for EntriesAndTxidsDisjoint
219      BOOST_CHECK(EntriesAndTxidsDisjoint(empty_set, {tx1->GetHash()}, unused_txid) == std::nullopt);
220      BOOST_CHECK(EntriesAndTxidsDisjoint(set_12_normal, {tx3->GetHash()}, unused_txid) == std::nullopt);
221      BOOST_CHECK(EntriesAndTxidsDisjoint({entry2_normal}, {tx2->GetHash()}, unused_txid).has_value());
222      BOOST_CHECK(EntriesAndTxidsDisjoint(set_12_normal, {tx1->GetHash()}, unused_txid).has_value());
223      BOOST_CHECK(EntriesAndTxidsDisjoint(set_12_normal, {tx2->GetHash()}, unused_txid).has_value());
224      // EntriesAndTxidsDisjoint does not calculate descendants of iters_conflicting; it uses whatever
225      // the caller passed in. As such, no error is returned even though entry2_normal is a descendant of tx1.
226      BOOST_CHECK(EntriesAndTxidsDisjoint({entry2_normal}, {tx1->GetHash()}, unused_txid) == std::nullopt);
227  
228      // Tests for PaysForRBF
229      const CFeeRate incremental_relay_feerate{DEFAULT_INCREMENTAL_RELAY_FEE};
230      const CFeeRate higher_relay_feerate{2 * DEFAULT_INCREMENTAL_RELAY_FEE};
231      // Must pay at least as much as the original.
232      BOOST_CHECK(PaysForRBF(/*original_fees=*/high_fee,
233                             /*replacement_fees=*/high_fee,
234                             /*replacement_vsize=*/1,
235                             /*relay_fee=*/CFeeRate(0),
236                             /*txid=*/unused_txid)
237                             == std::nullopt);
238      BOOST_CHECK(PaysForRBF(high_fee, high_fee - 1, 1, CFeeRate(0), unused_txid).has_value());
239      BOOST_CHECK(PaysForRBF(high_fee + 1, high_fee, 1, CFeeRate(0), unused_txid).has_value());
240      // Additional fees must cover the replacement's vsize at incremental relay fee
241      BOOST_CHECK(PaysForRBF(high_fee, high_fee + 1, 2, incremental_relay_feerate, unused_txid).has_value());
242      BOOST_CHECK(PaysForRBF(high_fee, high_fee + 2, 2, incremental_relay_feerate, unused_txid) == std::nullopt);
243      BOOST_CHECK(PaysForRBF(high_fee, high_fee + 2, 2, higher_relay_feerate, unused_txid).has_value());
244      BOOST_CHECK(PaysForRBF(high_fee, high_fee + 4, 2, higher_relay_feerate, unused_txid) == std::nullopt);
245      BOOST_CHECK(PaysForRBF(low_fee, high_fee, 99999999, incremental_relay_feerate, unused_txid).has_value());
246      BOOST_CHECK(PaysForRBF(low_fee, high_fee + 99999999, 99999999, incremental_relay_feerate, unused_txid) == std::nullopt);
247  
248      // Tests for GetEntriesForConflicts
249      CTxMemPool::setEntries all_parents{entry1_normal, entry3_low, entry5_low, entry7_high, entry8_high};
250      CTxMemPool::setEntries all_children{entry2_normal, entry4_high, entry6_low_prioritised};
251      const std::vector<CTransactionRef> parent_inputs({m_coinbase_txns[0], m_coinbase_txns[1], m_coinbase_txns[2],
252                                                  m_coinbase_txns[3], m_coinbase_txns[4]});
253      const auto conflicts_with_parents = make_tx(parent_inputs, {50 * CENT});
254      CTxMemPool::setEntries all_conflicts;
255      BOOST_CHECK(GetEntriesForConflicts(/*tx=*/ *conflicts_with_parents.get(),
256                                         /*pool=*/ pool,
257                                         /*iters_conflicting=*/ all_parents,
258                                         /*all_conflicts=*/ all_conflicts) == std::nullopt);
259      BOOST_CHECK(all_conflicts == all_entries);
260      auto conflicts_size = all_conflicts.size();
261      all_conflicts.clear();
262  
263      add_descendants(tx2, 23, pool);
264      BOOST_CHECK(GetEntriesForConflicts(*conflicts_with_parents.get(), pool, all_parents, all_conflicts) == std::nullopt);
265      conflicts_size += 23;
266      BOOST_CHECK_EQUAL(all_conflicts.size(), conflicts_size);
267      all_conflicts.clear();
268  
269      add_descendants(tx4, 23, pool);
270      BOOST_CHECK(GetEntriesForConflicts(*conflicts_with_parents.get(), pool, all_parents, all_conflicts) == std::nullopt);
271      conflicts_size += 23;
272      BOOST_CHECK_EQUAL(all_conflicts.size(), conflicts_size);
273      all_conflicts.clear();
274  
275      add_descendants(tx6, 23, pool);
276      BOOST_CHECK(GetEntriesForConflicts(*conflicts_with_parents.get(), pool, all_parents, all_conflicts) == std::nullopt);
277      conflicts_size += 23;
278      BOOST_CHECK_EQUAL(all_conflicts.size(), conflicts_size);
279      all_conflicts.clear();
280  
281      add_descendants(tx7, 23, pool);
282      BOOST_CHECK(GetEntriesForConflicts(*conflicts_with_parents.get(), pool, all_parents, all_conflicts) == std::nullopt);
283      conflicts_size += 23;
284      BOOST_CHECK_EQUAL(all_conflicts.size(), conflicts_size);
285      BOOST_CHECK_EQUAL(all_conflicts.size(), 100);
286      all_conflicts.clear();
287  
288      // Exceeds maximum number of conflicts.
289      add_descendants(tx8, 1, pool);
290      BOOST_CHECK(GetEntriesForConflicts(*conflicts_with_parents.get(), pool, all_parents, all_conflicts).has_value());
291  
292      // Tests for HasNoNewUnconfirmed
293      const auto spends_unconfirmed = make_tx({tx1}, {36 * CENT});
294      for (const auto& input : spends_unconfirmed->vin) {
295          // Spends unconfirmed inputs.
296          BOOST_CHECK(pool.exists(GenTxid::Txid(input.prevout.hash)));
297      }
298      BOOST_CHECK(HasNoNewUnconfirmed(/*tx=*/ *spends_unconfirmed.get(),
299                                      /*pool=*/ pool,
300                                      /*iters_conflicting=*/ all_entries) == std::nullopt);
301      BOOST_CHECK(HasNoNewUnconfirmed(*spends_unconfirmed.get(), pool, {entry2_normal}) == std::nullopt);
302      BOOST_CHECK(HasNoNewUnconfirmed(*spends_unconfirmed.get(), pool, empty_set).has_value());
303  
304      const auto spends_new_unconfirmed = make_tx({tx1, tx8}, {36 * CENT});
305      BOOST_CHECK(HasNoNewUnconfirmed(*spends_new_unconfirmed.get(), pool, {entry2_normal}).has_value());
306      BOOST_CHECK(HasNoNewUnconfirmed(*spends_new_unconfirmed.get(), pool, all_entries).has_value());
307  
308      const auto spends_conflicting_confirmed = make_tx({m_coinbase_txns[0], m_coinbase_txns[1]}, {45 * CENT});
309      BOOST_CHECK(HasNoNewUnconfirmed(*spends_conflicting_confirmed.get(), pool, {entry1_normal, entry3_low}) == std::nullopt);
310  
311      // Tests for CheckConflictTopology
312  
313      // Tx4 has 23 descendants
314      BOOST_CHECK_EQUAL(pool.CheckConflictTopology(set_34_cpfp).value(), strprintf("%s has 23 descendants, max 1 allowed", entry4_high->GetSharedTx()->GetHash().ToString()));
315  
316      // No descendants yet
317      BOOST_CHECK(pool.CheckConflictTopology({entry9_unchained}) == std::nullopt);
318  
319      // Add 1 descendant, still ok
320      add_descendants(tx9, 1, pool);
321      BOOST_CHECK(pool.CheckConflictTopology({entry9_unchained}) == std::nullopt);
322  
323      // N direct conflicts; ok
324      BOOST_CHECK(pool.CheckConflictTopology({entry9_unchained, entry10_unchained, entry11_unchained}) == std::nullopt);
325  
326      // Add 1 descendant, still ok, even if it's considered a direct conflict as well
327      const auto child_tx = add_descendants(tx10, 1, pool);
328      const auto entry10_child = pool.GetIter(child_tx->GetHash()).value();
329      BOOST_CHECK(pool.CheckConflictTopology({entry9_unchained, entry10_unchained, entry11_unchained}) == std::nullopt);
330      BOOST_CHECK(pool.CheckConflictTopology({entry9_unchained, entry10_unchained, entry11_unchained, entry10_child}) == std::nullopt);
331  
332      // One more, size 3 cluster too much
333      const auto grand_child_tx = add_descendants(child_tx, 1, pool);
334      const auto entry10_grand_child = pool.GetIter(grand_child_tx->GetHash()).value();
335      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry9_unchained, entry10_unchained, entry11_unchained}).value(), strprintf("%s has 2 descendants, max 1 allowed", entry10_unchained->GetSharedTx()->GetHash().ToString()));
336      // even if direct conflict is descendent itself
337      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry9_unchained, entry10_grand_child, entry11_unchained}).value(), strprintf("%s has 2 ancestors, max 1 allowed", entry10_grand_child->GetSharedTx()->GetHash().ToString()));
338  
339      // Make a single child from two singleton parents
340      const auto two_parent_child_tx = add_descendant_to_parents({tx11, tx12}, pool);
341      const auto entry_two_parent_child = pool.GetIter(two_parent_child_tx->GetHash()).value();
342      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry11_unchained}).value(), strprintf("%s is not the only parent of child %s", entry11_unchained->GetSharedTx()->GetHash().ToString(), entry_two_parent_child->GetSharedTx()->GetHash().ToString()));
343      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry12_unchained}).value(), strprintf("%s is not the only parent of child %s", entry12_unchained->GetSharedTx()->GetHash().ToString(), entry_two_parent_child->GetSharedTx()->GetHash().ToString()));
344      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry_two_parent_child}).value(), strprintf("%s has 2 ancestors, max 1 allowed", entry_two_parent_child->GetSharedTx()->GetHash().ToString()));
345  
346      // Single parent with two children, we will conflict with the siblings directly only
347      const auto two_siblings = add_children_to_parent(tx13, pool);
348      const auto entry_sibling_1 = pool.GetIter(two_siblings.first->GetHash()).value();
349      const auto entry_sibling_2 = pool.GetIter(two_siblings.second->GetHash()).value();
350      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry_sibling_1}).value(), strprintf("%s is not the only child of parent %s", entry_sibling_1->GetSharedTx()->GetHash().ToString(), entry13_unchained->GetSharedTx()->GetHash().ToString()));
351      BOOST_CHECK_EQUAL(pool.CheckConflictTopology({entry_sibling_2}).value(), strprintf("%s is not the only child of parent %s", entry_sibling_2->GetSharedTx()->GetHash().ToString(), entry13_unchained->GetSharedTx()->GetHash().ToString()));
352  
353  }
354  
355  BOOST_FIXTURE_TEST_CASE(improves_feerate, TestChain100Setup)
356  {
357      CTxMemPool& pool = *Assert(m_node.mempool);
358      LOCK2(::cs_main, pool.cs);
359      TestMemPoolEntryHelper entry;
360  
361      const CAmount low_fee{CENT/100};
362      const CAmount normal_fee{CENT/10};
363  
364      // low feerate parent with normal feerate child
365      const auto tx1 = make_tx(/*inputs=*/ {m_coinbase_txns[0], m_coinbase_txns[1]}, /*output_values=*/ {10 * COIN});
366      AddToMempool(pool, entry.Fee(low_fee).FromTx(tx1));
367      const auto tx2 = make_tx(/*inputs=*/ {tx1}, /*output_values=*/ {995 * CENT});
368      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx2));
369  
370      const auto entry1 = pool.GetIter(tx1->GetHash()).value();
371      const auto tx1_fee = entry1->GetModifiedFee();
372      const auto entry2 = pool.GetIter(tx2->GetHash()).value();
373      const auto tx2_fee = entry2->GetModifiedFee();
374  
375      // conflicting transactions
376      const auto tx1_conflict = make_tx(/*inputs=*/ {m_coinbase_txns[0], m_coinbase_txns[2]}, /*output_values=*/ {10 * COIN});
377      const auto tx3 = make_tx(/*inputs=*/ {tx1_conflict}, /*output_values=*/ {995 * CENT});
378      auto entry3 = entry.FromTx(tx3);
379  
380      // Now test ImprovesFeerateDiagram with various levels of "package rbf" feerates
381  
382      // It doesn't improve itself
383      auto changeset = pool.GetChangeSet();
384      changeset->StageRemoval(entry1);
385      changeset->StageRemoval(entry2);
386      changeset->StageAddition(tx1_conflict, tx1_fee, 0, 1, 0, false, 4, LockPoints());
387      changeset->StageAddition(tx3, tx2_fee, 0, 1, 0, false, 4, LockPoints());
388      const auto res1 = ImprovesFeerateDiagram(*changeset);
389      BOOST_CHECK(res1.has_value());
390      BOOST_CHECK(res1.value().first == DiagramCheckError::FAILURE);
391      BOOST_CHECK(res1.value().second == "insufficient feerate: does not improve feerate diagram");
392  
393      // With one more satoshi it does
394      changeset.reset();
395      changeset = pool.GetChangeSet();
396      changeset->StageRemoval(entry1);
397      changeset->StageRemoval(entry2);
398      changeset->StageAddition(tx1_conflict, tx1_fee+1, 0, 1, 0, false, 4, LockPoints());
399      changeset->StageAddition(tx3, tx2_fee, 0, 1, 0, false, 4, LockPoints());
400      BOOST_CHECK(ImprovesFeerateDiagram(*changeset) == std::nullopt);
401  
402      changeset.reset();
403      // With prioritisation of in-mempool conflicts, it affects the results of the comparison using the same args as just above
404      pool.PrioritiseTransaction(entry1->GetSharedTx()->GetHash(), /*nFeeDelta=*/1);
405      changeset = pool.GetChangeSet();
406      changeset->StageRemoval(entry1);
407      changeset->StageRemoval(entry2);
408      changeset->StageAddition(tx1_conflict, tx1_fee+1, 0, 1, 0, false, 4, LockPoints());
409      changeset->StageAddition(tx3, tx2_fee, 0, 1, 0, false, 4, LockPoints());
410      const auto res2 = ImprovesFeerateDiagram(*changeset);
411      BOOST_CHECK(res2.has_value());
412      BOOST_CHECK(res2.value().first == DiagramCheckError::FAILURE);
413      BOOST_CHECK(res2.value().second == "insufficient feerate: does not improve feerate diagram");
414      changeset.reset();
415  
416      pool.PrioritiseTransaction(entry1->GetSharedTx()->GetHash(), /*nFeeDelta=*/-1);
417  
418      // With fewer vbytes it does
419      CMutableTransaction tx4{entry3.GetTx()};
420      tx4.vin[0].scriptWitness = CScriptWitness(); // Clear out the witness, to reduce size
421      auto entry4 = entry.FromTx(MakeTransactionRef(tx4));
422      changeset = pool.GetChangeSet();
423      changeset->StageRemoval(entry1);
424      changeset->StageRemoval(entry2);
425      changeset->StageAddition(tx1_conflict, tx1_fee, 0, 1, 0, false, 4, LockPoints());
426      changeset->StageAddition(entry4.GetSharedTx(), tx2_fee, 0, 1, 0, false, 4, LockPoints());
427      BOOST_CHECK(ImprovesFeerateDiagram(*changeset) == std::nullopt);
428      changeset.reset();
429  
430      // Adding a grandchild makes the cluster size 3, which is uncalculable
431      const auto tx5 = make_tx(/*inputs=*/ {tx2}, /*output_values=*/ {995 * CENT});
432      AddToMempool(pool, entry.Fee(normal_fee).FromTx(tx5));
433      const auto entry5 = pool.GetIter(tx5->GetHash()).value();
434  
435      changeset = pool.GetChangeSet();
436      changeset->StageRemoval(entry1);
437      changeset->StageRemoval(entry2);
438      changeset->StageRemoval(entry5);
439      changeset->StageAddition(tx1_conflict, tx1_fee, 0, 1, 0, false, 4, LockPoints());
440      changeset->StageAddition(entry4.GetSharedTx(), tx2_fee + entry5->GetModifiedFee() + 1, 0, 1, 0, false, 4, LockPoints());
441      const auto res3 = ImprovesFeerateDiagram(*changeset);
442      BOOST_CHECK(res3.has_value());
443      BOOST_CHECK(res3.value().first == DiagramCheckError::UNCALCULABLE);
444      BOOST_CHECK(res3.value().second == strprintf("%s has 2 ancestors, max 1 allowed", tx5->GetHash().GetHex()));
445  }
446  
447  BOOST_FIXTURE_TEST_CASE(calc_feerate_diagram_rbf, TestChain100Setup)
448  {
449      CTxMemPool& pool = *Assert(m_node.mempool);
450      LOCK2(::cs_main, pool.cs);
451      TestMemPoolEntryHelper entry;
452  
453      const CAmount low_fee{CENT/100};
454      const CAmount normal_fee{CENT/10};
455      const CAmount high_fee{CENT};
456  
457      // low -> high -> medium fee transactions that would result in two chunks together since they
458      // are all same size
459      const auto low_tx = make_tx(/*inputs=*/ {m_coinbase_txns[0]}, /*output_values=*/ {10 * COIN});
460      AddToMempool(pool, entry.Fee(low_fee).FromTx(low_tx));
461  
462      const auto entry_low = pool.GetIter(low_tx->GetHash()).value();
463      const auto low_size = entry_low->GetTxSize();
464  
465      const auto replacement_tx = make_tx(/*inputs=*/ {m_coinbase_txns[0]}, /*output_values=*/ {9 * COIN});
466      auto entry_replacement = entry.FromTx(replacement_tx);
467  
468      // Replacement of size 1
469      {
470          auto changeset = pool.GetChangeSet();
471          changeset->StageRemoval(entry_low);
472          changeset->StageAddition(replacement_tx, 0, 0, 1, 0, false, 4, LockPoints());
473          const auto replace_one{changeset->CalculateChunksForRBF()};
474          BOOST_CHECK(replace_one.has_value());
475          std::vector<FeeFrac> expected_old_chunks{{low_fee, low_size}};
476          BOOST_CHECK(replace_one->first == expected_old_chunks);
477          std::vector<FeeFrac> expected_new_chunks{{0, int32_t(entry_replacement.GetTxSize())}};
478          BOOST_CHECK(replace_one->second == expected_new_chunks);
479      }
480  
481      // Non-zero replacement fee/size
482      {
483          auto changeset = pool.GetChangeSet();
484          changeset->StageRemoval(entry_low);
485          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
486          const auto replace_one_fee{changeset->CalculateChunksForRBF()};
487          BOOST_CHECK(replace_one_fee.has_value());
488          std::vector<FeeFrac> expected_old_diagram{{low_fee, low_size}};
489          BOOST_CHECK(replace_one_fee->first == expected_old_diagram);
490          std::vector<FeeFrac> expected_new_diagram{{high_fee, low_size}};
491          BOOST_CHECK(replace_one_fee->second == expected_new_diagram);
492      }
493  
494      // Add a second transaction to the cluster that will make a single chunk, to be evicted in the RBF
495      const auto high_tx = make_tx(/*inputs=*/ {low_tx}, /*output_values=*/ {995 * CENT});
496      AddToMempool(pool, entry.Fee(high_fee).FromTx(high_tx));
497      const auto entry_high = pool.GetIter(high_tx->GetHash()).value();
498      const auto high_size = entry_high->GetTxSize();
499  
500      {
501          auto changeset = pool.GetChangeSet();
502          changeset->StageRemoval(entry_low);
503          changeset->StageRemoval(entry_high);
504          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
505          const auto replace_single_chunk{changeset->CalculateChunksForRBF()};
506          BOOST_CHECK(replace_single_chunk.has_value());
507          std::vector<FeeFrac> expected_old_chunks{{low_fee + high_fee, low_size + high_size}};
508          BOOST_CHECK(replace_single_chunk->first == expected_old_chunks);
509          std::vector<FeeFrac> expected_new_chunks{{high_fee, low_size}};
510          BOOST_CHECK(replace_single_chunk->second == expected_new_chunks);
511      }
512  
513      // Conflict with the 2nd tx, resulting in new diagram with three entries
514      {
515          auto changeset = pool.GetChangeSet();
516          changeset->StageRemoval(entry_high);
517          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
518          const auto replace_cpfp_child{changeset->CalculateChunksForRBF()};
519          BOOST_CHECK(replace_cpfp_child.has_value());
520          std::vector<FeeFrac> expected_old_chunks{{low_fee + high_fee, low_size + high_size}};
521          BOOST_CHECK(replace_cpfp_child->first == expected_old_chunks);
522          std::vector<FeeFrac> expected_new_chunks{{high_fee, low_size}, {low_fee, low_size}};
523          BOOST_CHECK(replace_cpfp_child->second == expected_new_chunks);
524      }
525  
526      // third transaction causes the topology check to fail
527      const auto normal_tx = make_tx(/*inputs=*/ {high_tx}, /*output_values=*/ {995 * CENT});
528      AddToMempool(pool, entry.Fee(normal_fee).FromTx(normal_tx));
529      const auto entry_normal = pool.GetIter(normal_tx->GetHash()).value();
530  
531      {
532          auto changeset = pool.GetChangeSet();
533          changeset->StageRemoval(entry_low);
534          changeset->StageRemoval(entry_high);
535          changeset->StageRemoval(entry_normal);
536          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
537          const auto replace_too_large{changeset->CalculateChunksForRBF()};
538          BOOST_CHECK(!replace_too_large.has_value());
539          BOOST_CHECK_EQUAL(util::ErrorString(replace_too_large).original, strprintf("%s has 2 ancestors, max 1 allowed", normal_tx->GetHash().GetHex()));
540      }
541  
542      // Make a size 2 cluster that is itself two chunks; evict both txns
543      const auto high_tx_2 = make_tx(/*inputs=*/ {m_coinbase_txns[1]}, /*output_values=*/ {10 * COIN});
544      AddToMempool(pool, entry.Fee(high_fee).FromTx(high_tx_2));
545      const auto entry_high_2 = pool.GetIter(high_tx_2->GetHash()).value();
546      const auto high_size_2 = entry_high_2->GetTxSize();
547  
548      const auto low_tx_2 = make_tx(/*inputs=*/ {high_tx_2}, /*output_values=*/ {9 * COIN});
549      AddToMempool(pool, entry.Fee(low_fee).FromTx(low_tx_2));
550      const auto entry_low_2 = pool.GetIter(low_tx_2->GetHash()).value();
551      const auto low_size_2 = entry_low_2->GetTxSize();
552  
553      {
554          auto changeset = pool.GetChangeSet();
555          changeset->StageRemoval(entry_high_2);
556          changeset->StageRemoval(entry_low_2);
557          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
558          const auto replace_two_chunks_single_cluster{changeset->CalculateChunksForRBF()};
559          BOOST_CHECK(replace_two_chunks_single_cluster.has_value());
560          std::vector<FeeFrac> expected_old_chunks{{high_fee, high_size_2}, {low_fee, low_size_2}};
561          BOOST_CHECK(replace_two_chunks_single_cluster->first == expected_old_chunks);
562          std::vector<FeeFrac> expected_new_chunks{{high_fee, low_size_2}};
563          BOOST_CHECK(replace_two_chunks_single_cluster->second == expected_new_chunks);
564      }
565  
566      // You can have more than two direct conflicts if the there are multiple affected clusters, all of size 2 or less
567      const auto conflict_1 = make_tx(/*inputs=*/ {m_coinbase_txns[2]}, /*output_values=*/ {10 * COIN});
568      AddToMempool(pool, entry.Fee(low_fee).FromTx(conflict_1));
569      const auto conflict_1_entry = pool.GetIter(conflict_1->GetHash()).value();
570  
571      const auto conflict_2 = make_tx(/*inputs=*/ {m_coinbase_txns[3]}, /*output_values=*/ {10 * COIN});
572      AddToMempool(pool, entry.Fee(low_fee).FromTx(conflict_2));
573      const auto conflict_2_entry = pool.GetIter(conflict_2->GetHash()).value();
574  
575      const auto conflict_3 = make_tx(/*inputs=*/ {m_coinbase_txns[4]}, /*output_values=*/ {10 * COIN});
576      AddToMempool(pool, entry.Fee(low_fee).FromTx(conflict_3));
577      const auto conflict_3_entry = pool.GetIter(conflict_3->GetHash()).value();
578  
579      {
580          auto changeset = pool.GetChangeSet();
581          changeset->StageRemoval(conflict_1_entry);
582          changeset->StageRemoval(conflict_2_entry);
583          changeset->StageRemoval(conflict_3_entry);
584          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
585          const auto replace_multiple_clusters{changeset->CalculateChunksForRBF()};
586          BOOST_CHECK(replace_multiple_clusters.has_value());
587          BOOST_CHECK(replace_multiple_clusters->first.size() == 3);
588          BOOST_CHECK(replace_multiple_clusters->second.size() == 1);
589      }
590  
591      // Add a child transaction to conflict_1 and make it cluster size 2, two chunks due to same feerate
592      const auto conflict_1_child = make_tx(/*inputs=*/{conflict_1}, /*output_values=*/ {995 * CENT});
593      AddToMempool(pool, entry.Fee(low_fee).FromTx(conflict_1_child));
594      const auto conflict_1_child_entry = pool.GetIter(conflict_1_child->GetHash()).value();
595  
596      {
597          auto changeset = pool.GetChangeSet();
598          changeset->StageRemoval(conflict_1_entry);
599          changeset->StageRemoval(conflict_2_entry);
600          changeset->StageRemoval(conflict_3_entry);
601          changeset->StageRemoval(conflict_1_child_entry);
602          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
603          const auto replace_multiple_clusters_2{changeset->CalculateChunksForRBF()};
604  
605          BOOST_CHECK(replace_multiple_clusters_2.has_value());
606          BOOST_CHECK(replace_multiple_clusters_2->first.size() == 4);
607          BOOST_CHECK(replace_multiple_clusters_2->second.size() == 1);
608      }
609  
610      // Add another descendant to conflict_1, making the cluster size > 2 should fail at this point.
611      const auto conflict_1_grand_child = make_tx(/*inputs=*/{conflict_1_child}, /*output_values=*/ {995 * CENT});
612      AddToMempool(pool, entry.Fee(high_fee).FromTx(conflict_1_grand_child));
613      const auto conflict_1_grand_child_entry = pool.GetIter(conflict_1_child->GetHash()).value();
614  
615      {
616          auto changeset = pool.GetChangeSet();
617          changeset->StageRemoval(conflict_1_entry);
618          changeset->StageRemoval(conflict_2_entry);
619          changeset->StageRemoval(conflict_3_entry);
620          changeset->StageRemoval(conflict_1_child_entry);
621          changeset->StageRemoval(conflict_1_grand_child_entry);
622          changeset->StageAddition(replacement_tx, high_fee, 0, 1, 0, false, 4, LockPoints());
623          const auto replace_cluster_size_3{changeset->CalculateChunksForRBF()};
624  
625          BOOST_CHECK(!replace_cluster_size_3.has_value());
626          BOOST_CHECK_EQUAL(util::ErrorString(replace_cluster_size_3).original, strprintf("%s has both ancestor and descendant, exceeding cluster limit of 2", conflict_1_child->GetHash().GetHex()));
627      }
628  }
629  
630  BOOST_AUTO_TEST_CASE(feerate_chunks_utilities)
631  {
632      // Sanity check the correctness of the feerate chunks comparison.
633  
634      // A strictly better case.
635      std::vector<FeeFrac> old_chunks{{{950, 300}, {100, 100}}};
636      std::vector<FeeFrac> new_chunks{{{1000, 300}, {50, 100}}};
637  
638      BOOST_CHECK(std::is_lt(CompareChunks(old_chunks, new_chunks)));
639      BOOST_CHECK(std::is_gt(CompareChunks(new_chunks, old_chunks)));
640  
641      // Incomparable diagrams
642      old_chunks = {{950, 300}, {100, 100}};
643      new_chunks = {{1000, 300}, {0, 100}};
644  
645      BOOST_CHECK(CompareChunks(old_chunks, new_chunks) == std::partial_ordering::unordered);
646      BOOST_CHECK(CompareChunks(new_chunks, old_chunks) == std::partial_ordering::unordered);
647  
648      // Strictly better but smaller size.
649      old_chunks = {{950, 300}, {100, 100}};
650      new_chunks = {{1100, 300}};
651  
652      BOOST_CHECK(std::is_lt(CompareChunks(old_chunks, new_chunks)));
653      BOOST_CHECK(std::is_gt(CompareChunks(new_chunks, old_chunks)));
654  
655      // New diagram is strictly better due to the first chunk, even though
656      // second chunk contributes no fees
657      old_chunks = {{950, 300}, {100, 100}};
658      new_chunks = {{1100, 100}, {0, 100}};
659  
660      BOOST_CHECK(std::is_lt(CompareChunks(old_chunks, new_chunks)));
661      BOOST_CHECK(std::is_gt(CompareChunks(new_chunks, old_chunks)));
662  
663      // Feerate of first new chunk is better with, but second chunk is worse
664      old_chunks = {{950, 300}, {100, 100}};
665      new_chunks = {{750, 100}, {249, 250}, {151, 650}};
666  
667      BOOST_CHECK(CompareChunks(old_chunks, new_chunks) == std::partial_ordering::unordered);
668      BOOST_CHECK(CompareChunks(new_chunks, old_chunks) == std::partial_ordering::unordered);
669  
670      // If we make the second chunk slightly better, the new diagram now wins.
671      old_chunks = {{950, 300}, {100, 100}};
672      new_chunks = {{750, 100}, {250, 250}, {150, 150}};
673  
674      BOOST_CHECK(std::is_lt(CompareChunks(old_chunks, new_chunks)));
675      BOOST_CHECK(std::is_gt(CompareChunks(new_chunks, old_chunks)));
676  
677      // Identical diagrams, cannot be strictly better
678      old_chunks = {{950, 300}, {100, 100}};
679      new_chunks = {{950, 300}, {100, 100}};
680  
681      BOOST_CHECK(std::is_eq(CompareChunks(old_chunks, new_chunks)));
682      BOOST_CHECK(std::is_eq(CompareChunks(new_chunks, old_chunks)));
683  
684      // Same aggregate fee, but different total size (trigger single tail fee check step)
685      old_chunks = {{950, 300}, {100, 99}};
686      new_chunks = {{950, 300}, {100, 100}};
687  
688      // No change in evaluation when tail check needed.
689      BOOST_CHECK(std::is_gt(CompareChunks(old_chunks, new_chunks)));
690      BOOST_CHECK(std::is_lt(CompareChunks(new_chunks, old_chunks)));
691  
692      // Trigger multiple tail fee check steps
693      old_chunks = {{950, 300}, {100, 99}};
694      new_chunks = {{950, 300}, {100, 100}, {0, 1}, {0, 1}};
695  
696      BOOST_CHECK(std::is_gt(CompareChunks(old_chunks, new_chunks)));
697      BOOST_CHECK(std::is_lt(CompareChunks(new_chunks, old_chunks)));
698  
699      // Multiple tail fee check steps, unordered result
700      new_chunks = {{950, 300}, {100, 100}, {0, 1}, {0, 1}, {1, 1}};
701      BOOST_CHECK(CompareChunks(old_chunks, new_chunks) == std::partial_ordering::unordered);
702      BOOST_CHECK(CompareChunks(new_chunks, old_chunks) == std::partial_ordering::unordered);
703  }
704  
705  BOOST_AUTO_TEST_SUITE_END()