Allow zero-fee fundrawtxn and walletcreatefundedpsbt calls

A check to raise an error on zero-fee txns was mistakenly extended in commit
a0d4957 from the bumpfee and send{toaddress, many} RPCs to also include
fundrawtransaction and walletcreatefundedpsbt.

This commit overrides zero fee rate checking for these two RPCs, not only for
the feeRate (BTC/kvB) arg to return to previous behavior, but also for the new
fee_rate (sat/vB) arg.

Github-Pull: #20426
Rebased-From: 1b3d7009280595108eb22ac1188bc43678

1 files changed, 3 insertions, 13 deletions

diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 5cbdd1021a..428531c3da 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -217,14 +217,8 @@ static void SetFeeEstimateMode(const CWallet& wallet, CCoinControl& cc, const Un
         if (!estimate_mode.isNull() && estimate_mode.get_str() != "unset") {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "Cannot specify both estimate_mode and fee_rate");
         }
-        CFeeRate fee_rate_in_sat_vb{CFeeRate(AmountFromValue(fee_rate), COIN)};
-        if (override_min_fee) {
-            if (fee_rate_in_sat_vb <= CFeeRate(0)) {
-                throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid fee_rate %s (must be greater than 0)", fee_rate_in_sat_vb.ToString(FeeEstimateMode::SAT_VB)));
-            }
-            cc.fOverrideFeeRate = true;
-        }
-        cc.m_feerate = fee_rate_in_sat_vb;
+        cc.m_feerate = CFeeRate(AmountFromValue(fee_rate), COIN);
+        if (override_min_fee) cc.fOverrideFeeRate = true;
         // Default RBF to true for explicit fee_rate, if unset.
         if (cc.m_signal_bip125_rbf == nullopt) cc.m_signal_bip125_rbf = true;
         return;
@@ -3148,11 +3142,7 @@ void FundTransaction(CWallet* const pwallet, CMutableTransaction& tx, CAmount& f
             if (options.exists("estimate_mode")) {
                 throw JSONRPCError(RPC_INVALID_PARAMETER, "Cannot specify both estimate_mode and feeRate");
             }
-            CFeeRate fee_rate(AmountFromValue(options["feeRate"]));
-            if (fee_rate <= CFeeRate(0)) {
-                throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid feeRate %s (must be greater than 0)", fee_rate.ToString(FeeEstimateMode::BTC_KVB)));
-            }
-            coinControl.m_feerate = fee_rate;
+            coinControl.m_feerate = CFeeRate(AmountFromValue(options["feeRate"]));
             coinControl.fOverrideFeeRate = true;
         }