Merge bitcoin/bitcoin#22042: Replace size/weight estimate tuple with struct for named fields

881a3e2e17c5a6fdffb16a47a2eaff9029f261e5 Replace size/weight estimate tuple with struct for named fields (Gregory Sanders)

Pull request description:

  For clarity of return values of size estimation functions.

ACKs for top commit:
  MarcoFalke:
    review ACK 881a3e2e17c5a6fdffb16a47a2eaff9029f261e5
  practicalswift:
    cr ACK 881a3e2e17c5a6fdffb16a47a2eaff9029f261e5

Tree-SHA512: 9aa97e3774fcaf1e5b905259418d827051325c2ad76d6c7388ad7c687c605c024a6c5d2f7e9565f4c180ad1a9f6b179557fcb8b23371ff1a4f3b81300ac1f3d1

3 files changed, 17 insertions, 13 deletions

diff --git a/src/wallet/feebumper.cpp b/src/wallet/feebumper.cpp
index 08adf09df4..30fef50c3b 100644
--- a/src/wallet/feebumper.cpp
+++ b/src/wallet/feebumper.cpp
@@ -190,7 +190,7 @@ Result CreateRateBumpTransaction(CWallet& wallet, const uint256& txid, const CCo
     if (coin_control.m_feerate) {
         // The user provided a feeRate argument.
         // We calculate this here to avoid compiler warning on the cs_wallet lock
-        const int64_t maxTxSize = CalculateMaximumSignedTxSize(*wtx.tx, &wallet).first;
+        const int64_t maxTxSize{CalculateMaximumSignedTxSize(*wtx.tx, &wallet).vsize};
         Result res = CheckFeeRate(wallet, wtx, *new_coin_control.m_feerate, maxTxSize, errors);
         if (res != Result::OK) {
             return res;
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index e603ce7d0b..6c97a48561 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1627,15 +1627,14 @@ bool CWallet::ImportScriptPubKeys(const std::string& label, const std::set<CScri
     return true;
 }
 
-// Returns pair of vsize and weight
-std::pair<int64_t, int64_t> CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, bool use_max_sig)
+TxSize CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, bool use_max_sig)
 {
     std::vector<CTxOut> txouts;
     for (const CTxIn& input : tx.vin) {
         const auto mi = wallet->mapWallet.find(input.prevout.hash);
         // Can not estimate size without knowing the input details
         if (mi == wallet->mapWallet.end()) {
-            return std::make_pair(-1, -1);
+            return TxSize{-1, -1};
         }
         assert(input.prevout.n < mi->second.tx->vout.size());
         txouts.emplace_back(mi->second.tx->vout[input.prevout.n]);
@@ -1644,16 +1643,16 @@ std::pair<int64_t, int64_t> CalculateMaximumSignedTxSize(const CTransaction &tx,
 }
 
 // txouts needs to be in the order of tx.vin
-std::pair<int64_t, int64_t> CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, const std::vector<CTxOut>& txouts, bool use_max_sig)
+TxSize CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, const std::vector<CTxOut>& txouts, bool use_max_sig)
 {
     CMutableTransaction txNew(tx);
     if (!wallet->DummySignTx(txNew, txouts, use_max_sig)) {
-        return std::make_pair(-1, -1);
+        return TxSize{-1, -1};
     }
     CTransaction ctx(txNew);
     int64_t vsize = GetVirtualTransactionSize(ctx);
     int64_t weight = GetTransactionWeight(ctx);
-    return std::make_pair(vsize, weight);
+    return TxSize{vsize, weight};
 }
 
 int CalculateMaximumSignedInputSize(const CTxOut& txout, const CWallet* wallet, bool use_max_sig)
@@ -2820,7 +2819,7 @@ bool CWallet::CreateTransactionInternal(
 
     CMutableTransaction txNew;
     FeeCalculation feeCalc;
-    std::pair<int64_t, int64_t> tx_sizes;
+    TxSize tx_sizes;
     int nBytes;
     {
         std::set<CInputCoin> setCoins;
@@ -2967,7 +2966,7 @@ bool CWallet::CreateTransactionInternal(
 
             // Calculate the transaction fee
             tx_sizes = CalculateMaximumSignedTxSize(CTransaction(txNew), this, coin_control.fAllowWatchOnly);
-            nBytes = tx_sizes.first;
+            nBytes = tx_sizes.vsize;
             if (nBytes < 0) {
                 error = _("Signing transaction failed");
                 return false;
@@ -2992,7 +2991,7 @@ bool CWallet::CreateTransactionInternal(
 
                 // Because we have dropped this change, the tx size and required fee will be different, so let's recalculate those
                 tx_sizes = CalculateMaximumSignedTxSize(CTransaction(txNew), this, coin_control.fAllowWatchOnly);
-                nBytes = tx_sizes.first;
+                nBytes = tx_sizes.vsize;
                 fee_needed = coin_selection_params.m_effective_feerate.GetFee(nBytes);
             }
 
@@ -3072,7 +3071,7 @@ bool CWallet::CreateTransactionInternal(
 
         // Limit size
         if ((sign && GetTransactionWeight(*tx) > MAX_STANDARD_TX_WEIGHT) ||
-            (!sign && tx_sizes.second > MAX_STANDARD_TX_WEIGHT))
+            (!sign && tx_sizes.weight > MAX_STANDARD_TX_WEIGHT))
         {
             error = _("Transaction too large");
             return false;
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 5f48e77590..9a572bc610 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -1346,12 +1346,17 @@ public:
     }
 };
 
+struct TxSize {
+    int64_t vsize{-1};
+    int64_t weight{-1};
+};
+
 /** Calculate the size of the transaction assuming all signatures are max size
 * Use DummySignatureCreator, which inserts 71 byte signatures everywhere.
 * NOTE: this requires that all inputs must be in mapWallet (eg the tx should
 * be IsAllFromMe). */
-std::pair<int64_t, int64_t> CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, bool use_max_sig = false) EXCLUSIVE_LOCKS_REQUIRED(wallet->cs_wallet);
-std::pair<int64_t, int64_t> CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, const std::vector<CTxOut>& txouts, bool use_max_sig = false);
+TxSize CalculateMaximumSignedTxSize(const CTransaction& tx, const CWallet* wallet, bool use_max_sig = false) EXCLUSIVE_LOCKS_REQUIRED(wallet->cs_wallet);
+TxSize CalculateMaximumSignedTxSize(const CTransaction& tx, const CWallet* wallet, const std::vector<CTxOut>& txouts, bool use_max_sig = false);
 
 //! Add wallet name to persistent configuration so it will be loaded on startup.
 bool AddWalletSetting(interfaces::Chain& chain, const std::string& wallet_name);