[doc] fix docs and comments from v3

Author: glozow

doc/policy/mempool-replacements.md

@@ -12,7 +12,7 @@ other consensus and policy rules, each of the following conditions are met:
 
 1. The directly conflicting transactions all signal replaceability explicitly. A transaction is
    signaling BIP125 replaceability if any of its inputs have an nSequence number less than (0xffffffff - 1).
-   A transaction also signals replaceibility if its nVersion field is set to 3.
+   A transaction also signals replaceability if its nVersion field is set to 3.
 
    *Rationale*: See [BIP125
    explanation](https://github.com/bitcoin/bips/blob/master/bip-0125.mediawiki#motivation).

src/policy/v3_policy.cpp

@@ -81,17 +81,16 @@ std::optional<std::string> PackageV3Checks(const CTransactionRef& ptx, int64_t v
                                  vsize, V3_CHILD_MAX_VSIZE);
             }
 
+            // Exactly 1 parent exists, either in mempool or package. Find it.
             const auto parent_info = [&] {
                 if (mempool_ancestors.size() > 0) {
-                    // There's a parent in the mempool.
                     auto& mempool_parent = *mempool_ancestors.begin();
                     Assume(mempool_parent->GetCountWithDescendants() == 1);
                     return ParentInfo{mempool_parent->GetTx().GetHash(),
                                       mempool_parent->GetTx().GetWitnessHash(),
                                       mempool_parent->GetTx().nVersion,
                                       /*has_mempool_descendant=*/mempool_parent->GetCountWithDescendants() > 1};
                 } else {
-                    // Ancestor must be in the package. Find it.
                     auto& parent_index = in_package_parents.front();
                     auto& package_parent = package.at(parent_index);
                     return ParentInfo{package_parent->GetHash(),
@@ -184,7 +183,7 @@ std::optional<std::string> SingleV3Checks(const CTransactionRef& ptx,
     // The rest of the rules only apply to transactions with nVersion=3.
     if (ptx->nVersion != 3) return std::nullopt;
 
-    // Check that V3_ANCESTOR_LIMIT would not be violated, including both in-package and in-mempool.
+    // Check that V3_ANCESTOR_LIMIT would not be violated.
     if (mempool_ancestors.size() + 1 > V3_ANCESTOR_LIMIT) {
         return strprintf("tx %s (wtxid=%s) would have too many ancestors",
                          ptx->GetHash().ToString(), ptx->GetWitnessHash().ToString());

src/test/fuzz/tx_pool.cpp

@@ -407,8 +407,6 @@ FUZZ_TARGET(tx_pool, .init = initialize_tx_pool)
         const bool accepted = res.m_result_type == MempoolAcceptResult::ResultType::VALID;
         if (accepted) {
             txids.push_back(tx->GetHash());
-            // Only check fees if accepted and not bypass_limits, otherwise it's not guaranteed that
-            // trimming has happened for this tx and previous iterations.
             CheckMempoolV3Invariants(tx_pool);
         }
     }