Improve CFeeBumper interface, add comments, make use of std::move

src/wallet/feebumper.cpp

@@ -42,7 +42,7 @@ int64_t CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *pWal
 
 CFeeBumper::CFeeBumper(const CWallet *pWallet, const uint256 txidIn, int newConfirmTarget, bool specifiedConfirmTarget, CAmount totalFee, bool newTxReplaceable)
     :
-    txid(txidIn),
+    txid(std::move(txidIn)),
     nOldFee(0),
     nNewFee(0)
 {
@@ -229,6 +229,11 @@ CFeeBumper::CFeeBumper(const CWallet *pWallet, const uint256 txidIn, int newConf
     currentResult = BumpFeeResult::OK;
 }
 
+bool CFeeBumper::signTransaction(CWallet *pWallet)
+{
+     return pWallet->SignTransaction(mtx);
+}
+
 bool CFeeBumper::commit(CWallet *pWallet)
 {
     AssertLockHeld(pWallet->cs_wallet);

src/wallet/feebumper.h

@@ -28,9 +28,19 @@ public:
     const std::vector<std::string>& getErrors() const { return vErrors; }
     CAmount getOldFee() const { return nOldFee; }
     CAmount getNewFee() const { return nNewFee; }
-    CMutableTransaction* getBumpedTxRef() { return &mtx; }
     uint256 getBumpedTxId() const { return bumpedTxid; }
 
+    /* signs the new transaction,
+     * returns false if the tx couldn't be found or if it was
+     * improssible to create the signature(s)
+     */
+    bool signTransaction(CWallet *pWallet);
+
+    /* commits the fee bump,
+     * returns true, in case of CWallet::CommitTransaction was successful
+     * but, eventually sets vErrors if the tx could not be added to the mempool (will try later)
+     * or if the old transaction could not be marked as replaced
+     */
     bool commit(CWallet *pWalletNonConst);
 
 private:

src/wallet/rpcwallet.cpp

@@ -2895,7 +2895,7 @@ UniValue bumpfee(const JSONRPCRequest& request)
     }
 
     // sign bumped transaction
-    if (!pwallet->SignTransaction(*feeBump.getBumpedTxRef())) {
+    if (!feeBump.signTransaction(pwallet)) {
         throw JSONRPCError(RPC_WALLET_ERROR, "Can't sign transaction.");
     }
     // commit the bumped transaction