Merge #20510: [backport] wallet: allow zero-fee fundrawtransaction/walletcreatefundedpsbt and other fixes

6313362553d91bddb75a43f62dffbec16065e4d6 Use the correct incremental fee constant in bumpfee help (Jon Atack)
6e4969f76f58518d47ce2f2cdfc4e3ef1f2228bd Update feeRate (BTC/kvB) to fee_rate (sat/vB) in wallet_bumpfee (Jon Atack)
54e1edcc2bca76f783170768e65bf0850b036b81 Allow zero-fee fundrawtxn and walletcreatefundedpsbt calls (Jon Atack)

Pull request description:

  Github-Pull: #20426
  Rebased-From: 1b3d7009280595108eb22ac1188bc4367804fc5d

  Github-Pull: #20426
  Rebased-From: 3f1e10b2b1cd11f7112fbad6355464bd4adbbc5c

  Github-Pull: #20426
  Rebased-From: 9f08780dd7946b63476e9736745131db8e7f4e93

Top commit has no ACKs.

Tree-SHA512: 89556f69ca4a36d86d6ab5df740b6d5de809f13d45b03450fb526362b1eabd3d2d5285f97c552dc0bcb07e17ac2e6c557ff46335962e6bcf366d36ad412f257c

1 files changed, 5 insertions, 16 deletions

diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 5cbdd1021a..9ba10e6c39 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -29,7 +29,6 @@
 #include <util/translation.h>
 #include <util/url.h>
 #include <util/vector.h>
-#include <validation.h>
 #include <wallet/coincontrol.h>
 #include <wallet/context.h>
 #include <wallet/feebumper.h>
@@ -217,14 +216,8 @@ 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 +3141,7 @@ 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;
         }
 
@@ -3391,7 +3380,7 @@ RPCHelpMan signrawtransactionwithwallet()
 static RPCHelpMan bumpfee_helper(std::string method_name)
 {
     bool want_psbt = method_name == "psbtbumpfee";
-    const std::string incremental_fee{CFeeRate(DEFAULT_MIN_RELAY_TX_FEE).ToString(FeeEstimateMode::SAT_VB)};
+    const std::string incremental_fee{CFeeRate(DEFAULT_INCREMENTAL_RELAY_FEE).ToString(FeeEstimateMode::SAT_VB)};
 
     return RPCHelpMan{method_name,
         "\nBumps the fee of an opt-in-RBF transaction T, replacing it with a new transaction B.\n"
@@ -3414,7 +3403,7 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
                     {"conf_target", RPCArg::Type::NUM, /* default */ "wallet -txconfirmtarget", "Confirmation target in blocks\n"},
                     {"fee_rate", RPCArg::Type::AMOUNT, /* default */ "not set, fall back to wallet fee estimation",
                              "\nSpecify a fee rate in " + CURRENCY_ATOM + "/vB instead of relying on the built-in fee estimator.\n"
-                             "Must be at least " + incremental_fee + " " + CURRENCY_ATOM + "/vB higher than the current transaction fee rate.\n"
+                             "Must be at least " + incremental_fee + " higher than the current transaction fee rate.\n"
                              "WARNING: before version 0.21, fee_rate was in " + CURRENCY_UNIT + "/kvB. As of 0.21, fee_rate is in " + CURRENCY_ATOM + "/vB.\n"},
                     {"replaceable", RPCArg::Type::BOOL, /* default */ "true", "Whether the new transaction should still be\n"
                              "marked bip-125 replaceable. If true, the sequence numbers in the transaction will\n"