Refactor to use CoinControl in GetMinimumFee and FeeBumper

Improve parameter precedence in coin_control

6 files changed, 66 insertions, 63 deletions

diff --git a/src/wallet/coincontrol.h b/src/wallet/coincontrol.h
index bdd01bec12..40c8b764b9 100644
--- a/src/wallet/coincontrol.h
+++ b/src/wallet/coincontrol.h
@@ -10,6 +10,8 @@
 #include "primitives/transaction.h"
 #include "wallet/wallet.h"
 
+#include <boost/optional.hpp>
+
 /** Coin Control Features. */
 class CCoinControl
 {
@@ -19,12 +21,12 @@ public:
     bool fAllowOtherInputs;
     //! Includes watch only addresses which match the ISMINE_WATCH_SOLVABLE criteria
     bool fAllowWatchOnly;
-    //! Override estimated feerate
+    //! Override automatic min/max checks on fee, m_feerate must be set if true
     bool fOverrideFeeRate;
-    //! Feerate to use if overrideFeeRate is true
-    CFeeRate nFeeRate;
-    //! Override the default confirmation target, 0 = use default
-    int nConfirmTarget;
+    //! Override the default payTxFee if set
+    boost::optional<CFeeRate> m_feerate;
+    //! Override the default confirmation target if set
+    boost::optional<unsigned int> m_confirm_target;
     //! Signal BIP-125 replace by fee.
     bool signalRbf;
     //! Fee estimation mode to control arguments to estimateSmartFee
@@ -41,9 +43,9 @@ public:
         fAllowOtherInputs = false;
         fAllowWatchOnly = false;
         setSelected.clear();
-        nFeeRate = CFeeRate(0);
+        m_feerate = boost::none;
         fOverrideFeeRate = false;
-        nConfirmTarget = 0;
+        m_confirm_target = boost::none;
         signalRbf = fWalletRbf;
         m_fee_mode = FeeEstimateMode::UNSET;
     }
diff --git a/src/wallet/feebumper.cpp b/src/wallet/feebumper.cpp
index 607ecf4182..4bfd8726a5 100644
--- a/src/wallet/feebumper.cpp
+++ b/src/wallet/feebumper.cpp
@@ -3,6 +3,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "consensus/validation.h"
+#include "wallet/coincontrol.h"
 #include "wallet/feebumper.h"
 #include "wallet/wallet.h"
 #include "policy/fees.h"
@@ -66,7 +67,7 @@ bool CFeeBumper::preconditionChecks(const CWallet *pWallet, const CWalletTx& wtx
     return true;
 }
 
-CFeeBumper::CFeeBumper(const CWallet *pWallet, const uint256 txidIn, int newConfirmTarget, bool ignoreGlobalPayTxFee, CAmount totalFee, bool newTxReplaceable, FeeEstimateMode fee_mode)
+CFeeBumper::CFeeBumper(const CWallet *pWallet, const uint256 txidIn, const CCoinControl& coin_control, CAmount totalFee)
     :
     txid(std::move(txidIn)),
     nOldFee(0),
@@ -165,8 +166,7 @@ CFeeBumper::CFeeBumper(const CWallet *pWallet, const uint256 txidIn, int newConf
         nNewFee = totalFee;
         nNewFeeRate = CFeeRate(totalFee, maxNewTxSize);
     } else {
-        bool conservative_estimate = CalculateEstimateType(fee_mode, newTxReplaceable);
-        nNewFee = CWallet::GetMinimumFee(maxNewTxSize, newConfirmTarget, mempool, ::feeEstimator, nullptr /* FeeCalculation */, ignoreGlobalPayTxFee, conservative_estimate);
+        nNewFee = CWallet::GetMinimumFee(maxNewTxSize, coin_control, mempool, ::feeEstimator, nullptr /* FeeCalculation */);
         nNewFeeRate = CFeeRate(nNewFee, maxNewTxSize);
 
         // New fee rate must be at least old rate + minimum incremental relay rate
@@ -221,7 +221,7 @@ CFeeBumper::CFeeBumper(const CWallet *pWallet, const uint256 txidIn, int newConf
     }
 
     // Mark new tx not replaceable, if requested.
-    if (!newTxReplaceable) {
+    if (!coin_control.signalRbf) {
         for (auto& input : mtx.vin) {
             if (input.nSequence < 0xfffffffe) input.nSequence = 0xfffffffe;
         }
diff --git a/src/wallet/feebumper.h b/src/wallet/feebumper.h
index 11e2f5f953..3d64e53c15 100644
--- a/src/wallet/feebumper.h
+++ b/src/wallet/feebumper.h
@@ -10,6 +10,7 @@
 class CWallet;
 class CWalletTx;
 class uint256;
+class CCoinControl;
 enum class FeeEstimateMode;
 
 enum class BumpFeeResult
@@ -25,7 +26,7 @@ enum class BumpFeeResult
 class CFeeBumper
 {
 public:
-    CFeeBumper(const CWallet *pWalletIn, const uint256 txidIn, int newConfirmTarget, bool ignoreGlobalPayTxFee, CAmount totalFee, bool newTxReplaceable, FeeEstimateMode fee_mode);
+    CFeeBumper(const CWallet *pWalletIn, const uint256 txidIn, const CCoinControl& coin_control, CAmount totalFee);
     BumpFeeResult getResult() const { return currentResult; }
     const std::vector<std::string>& getErrors() const { return vErrors; }
     CAmount getOldFee() const { return nOldFee; }
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 1916908922..c636fa8114 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -460,7 +460,7 @@ UniValue sendtoaddress(const JSONRPCRequest& request)
     }
 
     if (request.params.size() > 6 && !request.params[6].isNull()) {
-        coin_control.nConfirmTarget = request.params[6].get_int();
+        coin_control.m_confirm_target = request.params[6].get_int();
     }
 
     if (request.params.size() > 7 && !request.params[7].isNull()) {
@@ -981,7 +981,7 @@ UniValue sendmany(const JSONRPCRequest& request)
     }
 
     if (request.params.size() > 6 && !request.params[6].isNull()) {
-        coin_control.nConfirmTarget = request.params[6].get_int();
+        coin_control.m_confirm_target = request.params[6].get_int();
     }
 
     if (request.params.size() > 7 && !request.params[7].isNull()) {
@@ -2730,13 +2730,9 @@ UniValue fundrawtransaction(const JSONRPCRequest& request)
     RPCTypeCheck(request.params, {UniValue::VSTR});
 
     CCoinControl coinControl;
-    coinControl.destChange = CNoDestination();
     int changePosition = -1;
-    coinControl.fAllowWatchOnly = false;  // include watching
     bool lockUnspents = false;
     bool reserveChangeKey = true;
-    coinControl.nFeeRate = CFeeRate(0);
-    coinControl.fOverrideFeeRate = false;
     UniValue subtractFeeFromOutputs;
     std::set<int> setSubtractFeeFromOutputs;
 
@@ -2788,7 +2784,7 @@ UniValue fundrawtransaction(const JSONRPCRequest& request)
 
         if (options.exists("feeRate"))
         {
-            coinControl.nFeeRate = CFeeRate(AmountFromValue(options["feeRate"]));
+            coinControl.m_feerate = CFeeRate(AmountFromValue(options["feeRate"]));
             coinControl.fOverrideFeeRate = true;
         }
 
@@ -2799,7 +2795,7 @@ UniValue fundrawtransaction(const JSONRPCRequest& request)
             coinControl.signalRbf = options["replaceable"].get_bool();
         }
         if (options.exists("conf_target")) {
-            coinControl.nConfirmTarget = options["conf_target"].get_int();
+            coinControl.m_confirm_target = options["conf_target"].get_int();
         }
         if (options.exists("estimate_mode")) {
             if (!FeeModeFromString(options["estimate_mode"].get_str(), coinControl.m_fee_mode)) {
@@ -2905,11 +2901,9 @@ UniValue bumpfee(const JSONRPCRequest& request)
     hash.SetHex(request.params[0].get_str());
 
     // optional parameters
-    bool ignoreGlobalPayTxFee = false;
-    int newConfirmTarget = nTxConfirmTarget;
     CAmount totalFee = 0;
-    bool replaceable = true;
-    FeeEstimateMode fee_mode = FeeEstimateMode::UNSET;
+    CCoinControl coin_control;
+    coin_control.signalRbf = true;
     if (request.params.size() > 1) {
         UniValue options = request.params[1];
         RPCTypeCheckObj(options,
@@ -2924,14 +2918,11 @@ UniValue bumpfee(const JSONRPCRequest& request)
         if (options.exists("confTarget") && options.exists("totalFee")) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "confTarget and totalFee options should not both be set. Please provide either a confirmation target for fee estimation or an explicit total fee for the transaction.");
         } else if (options.exists("confTarget")) {
-            // If the user has explicitly set a confTarget in this rpc call,
-            // then override the default logic that uses the global payTxFee
-            // instead of the confirmation target.
-            ignoreGlobalPayTxFee = true;
-            newConfirmTarget = options["confTarget"].get_int();
-            if (newConfirmTarget <= 0) { // upper-bound will be checked by estimatefee/smartfee
+            int target = options["confTarget"].get_int();
+            if (target <= 0) { // FIXME: Check upper bound too
                 throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid confTarget (cannot be <= 0)");
             }
+            coin_control.m_confirm_target = target;
         } else if (options.exists("totalFee")) {
             totalFee = options["totalFee"].get_int64();
             if (totalFee <= 0) {
@@ -2940,10 +2931,10 @@ UniValue bumpfee(const JSONRPCRequest& request)
         }
 
         if (options.exists("replaceable")) {
-            replaceable = options["replaceable"].get_bool();
+            coin_control.signalRbf = options["replaceable"].get_bool();
         }
         if (options.exists("estimate_mode")) {
-            if (!FeeModeFromString(options["estimate_mode"].get_str(), fee_mode)) {
+            if (!FeeModeFromString(options["estimate_mode"].get_str(), coin_control.m_fee_mode)) {
                 throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid estimate_mode parameter");
             }
         }
@@ -2952,7 +2943,7 @@ UniValue bumpfee(const JSONRPCRequest& request)
     LOCK2(cs_main, pwallet->cs_wallet);
     EnsureWalletIsUnlocked(pwallet);
 
-    CFeeBumper feeBump(pwallet, hash, newConfirmTarget, ignoreGlobalPayTxFee, totalFee, replaceable, fee_mode);
+    CFeeBumper feeBump(pwallet, hash, coin_control, totalFee);
     BumpFeeResult res = feeBump.getResult();
     if (res != BumpFeeResult::OK)
     {
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index f69ae5268c..f010ff0ca1 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2721,17 +2721,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT
                     vin.scriptWitness.SetNull();
                 }
 
-                // Allow to override the default confirmation target over the CoinControl instance
-                int currentConfirmationTarget = nTxConfirmTarget;
-                if (coin_control.nConfirmTarget > 0)
-                    currentConfirmationTarget = coin_control.nConfirmTarget;
-
-                // Allow to override the default fee estimate mode over the CoinControl instance
-                bool conservative_estimate = CalculateEstimateType(coin_control.m_fee_mode, coin_control.signalRbf);
-
-                CAmount nFeeNeeded = GetMinimumFee(nBytes, currentConfirmationTarget, ::mempool, ::feeEstimator, &feeCalc, false /* ignoreGlobalPayTxFee */, conservative_estimate);
-                if (coin_control.fOverrideFeeRate)
-                    nFeeNeeded = coin_control.nFeeRate.GetFee(nBytes);
+                CAmount nFeeNeeded = GetMinimumFee(nBytes, coin_control, ::mempool, ::feeEstimator, &feeCalc);
 
                 // If we made it here and we aren't even able to meet the relay fee on the next pass, give up
                 // because we must be at the maximum allowed fee.
@@ -2756,7 +2746,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT
                     // new inputs. We now know we only need the smaller fee
                     // (because of reduced tx size) and so we should add a
                     // change output. Only try this once.
-                    CAmount fee_needed_for_change = GetMinimumFee(change_prototype_size, currentConfirmationTarget, ::mempool, ::feeEstimator, nullptr, false /* ignoreGlobalPayTxFee */, conservative_estimate);
+                    CAmount fee_needed_for_change = GetMinimumFee(change_prototype_size, coin_control, ::mempool, ::feeEstimator, nullptr);
                     CAmount minimum_value_for_change = GetDustThreshold(change_prototype_txout, ::dustRelayFee);
                     CAmount max_excess_fee = fee_needed_for_change + minimum_value_for_change;
                     if (nFeeRet > nFeeNeeded + max_excess_fee && nChangePosInOut == -1 && nSubtractFeeFromAmount == 0 && pick_new_inputs) {
@@ -2932,33 +2922,52 @@ CAmount CWallet::GetRequiredFee(unsigned int nTxBytes)
     return std::max(minTxFee.GetFee(nTxBytes), ::minRelayTxFee.GetFee(nTxBytes));
 }
 
-CAmount CWallet::GetMinimumFee(unsigned int nTxBytes, unsigned int nConfirmTarget, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation *feeCalc, bool ignoreGlobalPayTxFee, bool conservative_estimate)
+CAmount CWallet::GetMinimumFee(unsigned int nTxBytes, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation *feeCalc)
 {
-    // payTxFee is the user-set global for desired feerate
-    CAmount nFeeNeeded = payTxFee.GetFee(nTxBytes);
-    // User didn't set: use -txconfirmtarget to estimate...
-    if (nFeeNeeded == 0 || ignoreGlobalPayTxFee) {
-        nFeeNeeded = estimator.estimateSmartFee(nConfirmTarget, feeCalc, pool, conservative_estimate).GetFee(nTxBytes);
-        // ... unless we don't have enough mempool data for estimatefee, then use fallbackFee
-        if (nFeeNeeded == 0) {
-            nFeeNeeded = fallbackFee.GetFee(nTxBytes);
+    /* User control of how to calculate fee uses the following parameter precedence:
+       1. coin_control.m_feerate
+       2. coin_control.m_confirm_target
+       3. payTxFee (user-set global variable)
+       4. nTxConfirmTarget (user-set global variable)
+       The first parameter that is set is used.
+    */
+    CAmount fee_needed;
+    if (coin_control.m_feerate) { // 1.
+        fee_needed = coin_control.m_feerate->GetFee(nTxBytes);
+        if (feeCalc) feeCalc->reason = FeeReason::PAYTXFEE;
+        // Allow to override automatic min/max check over coin control instance
+        if (coin_control.fOverrideFeeRate) return fee_needed;
+    }
+    else if (!coin_control.m_confirm_target && ::payTxFee != CFeeRate(0)) { // 3. TODO: remove magic value of 0 for global payTxFee
+        fee_needed = ::payTxFee.GetFee(nTxBytes);
+        if (feeCalc) feeCalc->reason = FeeReason::PAYTXFEE;
+    }
+    else { // 2. or 4.
+        // We will use smart fee estimation
+        unsigned int target = coin_control.m_confirm_target ? *coin_control.m_confirm_target : ::nTxConfirmTarget;
+        // Allow to override the default fee estimate mode over the CoinControl instance
+        bool conservative_estimate = CalculateEstimateType(coin_control.m_fee_mode, coin_control.signalRbf);
+
+        fee_needed = estimator.estimateSmartFee(target, feeCalc, pool, conservative_estimate).GetFee(nTxBytes);
+        if (fee_needed == 0) {
+            // if we don't have enough data for estimateSmartFee, then use fallbackFee
+            fee_needed = fallbackFee.GetFee(nTxBytes);
             if (feeCalc) feeCalc->reason = FeeReason::FALLBACK;
         }
-    } else {
-        if (feeCalc) feeCalc->reason = FeeReason::PAYTXFEE;
     }
+
     // prevent user from paying a fee below minRelayTxFee or minTxFee
-    CAmount requiredFee = GetRequiredFee(nTxBytes);
-    if (requiredFee > nFeeNeeded) {
-        nFeeNeeded = requiredFee;
+    CAmount required_fee = GetRequiredFee(nTxBytes);
+    if (required_fee > fee_needed) {
+        fee_needed = required_fee;
         if (feeCalc) feeCalc->reason = FeeReason::REQUIRED;
     }
     // But always obey the maximum
-    if (nFeeNeeded > maxTxFee) {
-        nFeeNeeded = maxTxFee;
+    if (fee_needed > maxTxFee) {
+        fee_needed = maxTxFee;
         if (feeCalc) feeCalc->reason = FeeReason::MAXTXFEE;
     }
-    return nFeeNeeded;
+    return fee_needed;
 }
 
 
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index d8717ea179..3c866776fb 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -964,7 +964,7 @@ public:
      * Estimate the minimum fee considering user set parameters
      * and the required fee
      */
-    static CAmount GetMinimumFee(unsigned int nTxBytes, unsigned int nConfirmTarget, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation *feeCalc, bool ignoreGlobalPayTxFee, bool conservative_estimate);
+    static CAmount GetMinimumFee(unsigned int nTxBytes, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation *feeCalc);
     /**
      * Return the minimum required fee taking into account the
      * floating relay fee and user set minimum transaction fee