bitcoind: fix the detection of unconfirmed RBF spending txs

As we walk through the spend transactions in the wallet, we may return
the txid of the transaction that was replaced instead of the new one.

src/bitcoin/d/mod.rs

@@ -916,9 +916,25 @@ impl BitcoinD {
  let input_outpoint = bitcoin::OutPoint { txid, vout };
 
  if spent_outpoint == &input_outpoint {
- return bitcoin::Txid::from_str(spending_txid)
- .map(Some)
- .expect("Must be a valid txid");
+ let spending_txid =
+ bitcoin::Txid::from_str(spending_txid).expect("Must be a valid txid");
+
+ // If the spending transaction is unconfirmed, there may more than one of them.
+ // Make sure to not return one that RBF'd.
+ let confs = gettx_res
+ .get("confirmations")
+ .and_then(Json::as_i64)
+ .expect("A valid number of confirmations must always be present.");
+ let conflicts = gettx_res
+ .get("walletconflicts")
+ .and_then(Json::as_array)
+ .expect("A valid list of wallet conflicts must always be present.");
+ if confs == 0 && !conflicts.is_empty() && !self.is_in_mempool(&spending_txid) {
+ log::debug!("Noticed '{}' as spending '{}', but is unconfirmed with conflicts and is not in mempool anymore. Discarding it.", &spending_txid, &spent_outpoint);
+ break;
+ }
+
+ return Some(spending_txid);
  }
  }
  }