wallet: Rename nFeeRet in CreateTransactionInternal to current_fee

nFeeRet represents the fee that the transaction currently pays. Update
it's name to reflect that.

Author: achow101

src/wallet/spend.cpp

@@ -778,7 +778,6 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
     AssertLockHeld(wallet.cs_wallet);
 
     // out variables, to be packed into returned result structure
-    CAmount nFeeRet;
     int nChangePosInOut = change_pos;
 
     FastRandomContext rng_fast;
@@ -960,24 +959,24 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
         return util::Error{_("Missing solving data for estimating transaction size")};
     }
     CAmount fee_needed = coin_selection_params.m_effective_feerate.GetFee(nBytes);
-    nFeeRet = result->GetSelectedValue() - recipients_sum - change_amount;
+    CAmount current_fee = result->GetSelectedValue() - recipients_sum - change_amount;
 
     // The only time that fee_needed should be less than the amount available for fees is when
     // we are subtracting the fee from the outputs. If this occurs at any other time, it is a bug.
-    if (!coin_selection_params.m_subtract_fee_outputs && fee_needed > nFeeRet) {
+    if (!coin_selection_params.m_subtract_fee_outputs && fee_needed > current_fee) {
         return util::Error{Untranslated(STR_INTERNAL_BUG("Fee needed > fee paid"))};
     }
 
     // If there is a change output and we overpay the fees then increase the change to match the fee needed
-    if (nChangePosInOut != -1 && fee_needed < nFeeRet) {
+    if (nChangePosInOut != -1 && fee_needed < current_fee) {
         auto& change = txNew.vout.at(nChangePosInOut);
-        change.nValue += nFeeRet - fee_needed;
-        nFeeRet = fee_needed;
+        change.nValue += current_fee - fee_needed;
+        current_fee = fee_needed;
     }
 
     // Reduce output values for subtractFeeFromAmount
     if (coin_selection_params.m_subtract_fee_outputs) {
-        CAmount to_reduce = fee_needed - nFeeRet;
+        CAmount to_reduce = fee_needed - current_fee;
         int i = 0;
         bool fFirst = true;
         for (const auto& recipient : vecSend)
@@ -1008,7 +1007,7 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
             }
             ++i;
         }
-        nFeeRet = fee_needed;
+        current_fee = fee_needed;
     }
 
     // Give up if change keypool ran out and change is required
@@ -1030,7 +1029,7 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
         return util::Error{_("Transaction too large")};
     }
 
-    if (nFeeRet > wallet.m_default_max_tx_fee) {
+    if (current_fee > wallet.m_default_max_tx_fee) {
         return util::Error{TransactionErrorString(TransactionError::MAX_FEE_EXCEEDED)};
     }
 
@@ -1046,14 +1045,14 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
     reservedest.KeepDestination();
 
     wallet.WalletLogPrintf("Fee Calculation: Fee:%d Bytes:%u Tgt:%d (requested %d) Reason:\"%s\" Decay %.5f: Estimation: (%g - %g) %.2f%% %.1f/(%.1f %d mem %.1f out) Fail: (%g - %g) %.2f%% %.1f/(%.1f %d mem %.1f out)\n",
-              nFeeRet, nBytes, feeCalc.returnedTarget, feeCalc.desiredTarget, StringForFeeReason(feeCalc.reason), feeCalc.est.decay,
+              current_fee, nBytes, feeCalc.returnedTarget, feeCalc.desiredTarget, StringForFeeReason(feeCalc.reason), feeCalc.est.decay,
               feeCalc.est.pass.start, feeCalc.est.pass.end,
               (feeCalc.est.pass.totalConfirmed + feeCalc.est.pass.inMempool + feeCalc.est.pass.leftMempool) > 0.0 ? 100 * feeCalc.est.pass.withinTarget / (feeCalc.est.pass.totalConfirmed + feeCalc.est.pass.inMempool + feeCalc.est.pass.leftMempool) : 0.0,
               feeCalc.est.pass.withinTarget, feeCalc.est.pass.totalConfirmed, feeCalc.est.pass.inMempool, feeCalc.est.pass.leftMempool,
               feeCalc.est.fail.start, feeCalc.est.fail.end,
               (feeCalc.est.fail.totalConfirmed + feeCalc.est.fail.inMempool + feeCalc.est.fail.leftMempool) > 0.0 ? 100 * feeCalc.est.fail.withinTarget / (feeCalc.est.fail.totalConfirmed + feeCalc.est.fail.inMempool + feeCalc.est.fail.leftMempool) : 0.0,
               feeCalc.est.fail.withinTarget, feeCalc.est.fail.totalConfirmed, feeCalc.est.fail.inMempool, feeCalc.est.fail.leftMempool);
-    return CreatedTransactionResult(tx, nFeeRet, nChangePosInOut, feeCalc);
+    return CreatedTransactionResult(tx, current_fee, nChangePosInOut, feeCalc);
 }
 
 util::Result<CreatedTransactionResult> CreateTransaction(