Merge bitcoin/bitcoin#27307: wallet: track mempool conflicts with wallet transactions

5952292133d6cc889f51ae771f2e0557311e1efe wallet, rpc: show mempool conflicts in `gettransaction` result (ishaanam)
54e07ee22ff16fc68583ade0d2b8ffffc81d444a wallet: track mempool conflicts (ishaanam)
d64922b5903e5ffc8d2ce0e6761f99f173b60800 wallet refactor: use CWalletTx member functions to determine tx state (ishaanam)
ffe5ff1fb622a8da11b66289e1b778e45e449811 scripted-diff: wallet: s/TxStateConflicted/TxStateBlockConflicted (ishaanam)
180973a94180f9849bf7cb0dab7c9177a942efb8 test: Add tests for wallet mempool conflicts (ishaanam)

Pull request description:

  The `mempool_conflicts` variable is added to `CWalletTx`, it is a set of txids of txs in the mempool conflicting with the wallet tx or a wallet tx's parent. This PR only changes how mempool-conflicted txs are dealt with in memory.

  `IsSpent` now returns false for an output being spent by a mempool conflicted transaction where it previously returned true.

  A txid is added to `mempool_conflicts` during  `transactionAddedToMempool`. A txid is removed from `mempool_conflicts` during  `transactionRemovedFromMempool`.

  This PR also adds a `mempoolconflicts` field to the `gettransaction` wallet RPC result.

  Builds on #27145
  Second attempt at #18600

ACKs for top commit:
  achow101:
    ACK 5952292133d6cc889f51ae771f2e0557311e1efe
  ryanofsky:
    Code review ACK 5952292133d6cc889f51ae771f2e0557311e1efe. Just small suggested changes since last review
  furszy:
    ACK 59522921

Tree-SHA512: 615779606723dbb6c2e302681d8e58ae2052ffee52d721ee0389746ddbbcf4b4c4afacf01ddf42b6405bc6f883520524186a955bf6b628fe9b3ae54cffc56a29

1 files changed, 8 insertions, 0 deletions

diff --git a/src/wallet/rpc/transactions.cpp b/src/wallet/rpc/transactions.cpp
index e6c021d426..05b340995d 100644
--- a/src/wallet/rpc/transactions.cpp
+++ b/src/wallet/rpc/transactions.cpp
@@ -40,6 +40,10 @@ static void WalletTxToJSON(const CWallet& wallet, const CWalletTx& wtx, UniValue
     for (const uint256& conflict : wallet.GetTxConflicts(wtx))
         conflicts.push_back(conflict.GetHex());
     entry.pushKV("walletconflicts", conflicts);
+    UniValue mempool_conflicts(UniValue::VARR);
+    for (const Txid& mempool_conflict : wtx.mempool_conflicts)
+        mempool_conflicts.push_back(mempool_conflict.GetHex());
+    entry.pushKV("mempoolconflicts", mempool_conflicts);
     entry.pushKV("time", wtx.GetTxTime());
     entry.pushKV("timereceived", int64_t{wtx.nTimeReceived});
 
@@ -417,6 +421,10 @@ static std::vector<RPCResult> TransactionDescriptionString()
            }},
            {RPCResult::Type::STR_HEX, "replaced_by_txid", /*optional=*/true, "Only if 'category' is 'send'. The txid if this tx was replaced."},
            {RPCResult::Type::STR_HEX, "replaces_txid", /*optional=*/true, "Only if 'category' is 'send'. The txid if this tx replaces another."},
+           {RPCResult::Type::ARR, "mempoolconflicts", "Transactions that directly conflict with either this transaction or an ancestor transaction",
+           {
+               {RPCResult::Type::STR_HEX, "txid", "The transaction id."},
+           }},
            {RPCResult::Type::STR, "to", /*optional=*/true, "If a comment to is associated with the transaction."},
            {RPCResult::Type::NUM_TIME, "time", "The transaction time expressed in " + UNIX_EPOCH_TIME + "."},
            {RPCResult::Type::NUM_TIME, "timereceived", "The time received expressed in " + UNIX_EPOCH_TIME + "."},