Gate z_mergetoaddress as an experimental feature

qa/rpc-tests/wallet_mergetoaddress.py

@@ -19,11 +19,11 @@ class WalletMergeToAddressTest (BitcoinTestFramework):
         initialize_chain_clean(self.options.tmpdir, 4)
 
     def setup_network(self, split=False):
-        args = ['-debug=zrpcunsafe']
+        args = ['-debug=zrpcunsafe', '-experimentalfeatures', '-zmergetoaddress']
         self.nodes = []
         self.nodes.append(start_node(0, self.options.tmpdir, args))
         self.nodes.append(start_node(1, self.options.tmpdir, args))
-        args2 = ['-debug=zrpcunsafe', '-mempooltxinputlimit=7']
+        args2 = ['-debug=zrpcunsafe', '-experimentalfeatures', '-zmergetoaddress', '-mempooltxinputlimit=7']
         self.nodes.append(start_node(2, self.options.tmpdir, args2))
         connect_nodes_bi(self.nodes,0,1)
         connect_nodes_bi(self.nodes,1,2)

src/init.cpp

@@ -793,6 +793,8 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
         }
         else if (mapArgs.count("-paymentdisclosure")) {
             return InitError(_("Payment disclosure requires -experimentalfeatures."));
+        } else if (mapArgs.count("-zmergetoaddress")) {
+            return InitError(_("RPC method z_mergetoaddress requires -experimentalfeatures."));
         }
     }
 

src/wallet/rpcwallet.cpp

@@ -3759,9 +3759,16 @@ UniValue z_mergetoaddress(const UniValue& params, bool fHelp)
     if (!EnsureWalletIsAvailable(fHelp))
         return NullUniValue;
 
+    auto fEnableMergeToAddress = fExperimentalMode && GetBoolArg("-zmergetoaddress", false);
+    std::string strDisabledMsg = "";
+    if (!fEnableMergeToAddress) {
+        strDisabledMsg = "\nWARNING: z_mergetoaddress is DISABLED but can be enabled as an experimental feature.\n";
+    }
+
     if (fHelp || params.size() < 2 || params.size() > 6)
         throw runtime_error(
             "z_mergetoaddress [\"fromaddress\", ... ] \"toaddress\" ( fee ) ( transparent_limit ) ( shielded_limit ) ( memo )\n"
+            + strDisabledMsg +
             "\nMerge multiple UTXOs and notes into a single UTXO or note.  Coinbase UTXOs are ignored; use `z_shieldcoinbase`"
             "\nto combine those into a single note."
             "\n\nThis is an asynchronous operation, and UTXOs selected for merging will be locked.  If there is an error, they"
@@ -3807,6 +3814,10 @@ UniValue z_mergetoaddress(const UniValue& params, bool fHelp)
             + HelpExampleRpc("z_mergetoaddress", "[\"t1M72Sfpbz1BPpXFHz9m3CdqATR44Jvaydd\"], \"ztfaW34Gj9FrnGUEf833ywDVL62NWXBM81u6EQnM6VR45eYnXhwztecW1SjxA7JrmAXKJhxhj3vDNEpVCQoSvVoSpmbhtjf\"")
         );
 
+    if (!fEnableMergeToAddress) {
+        throw JSONRPCError(RPC_WALLET_ERROR, "Error: z_mergetoaddress is disabled.");
+    }
+
     LOCK2(cs_main, pwalletMain->cs_wallet);
 
     bool useAny = false;