RPC on_transfer_split error consistent with on_transfer if no tx sent

src/wallet/wallet_rpc_server.cpp

@@ -1003,6 +1003,13 @@ namespace tools
       std::vector<wallet2::pending_tx> ptx_vector = m_wallet->create_transactions_2(dsts, mixin, req.unlock_time, priority, extra, req.account_index, req.subaddr_indices);
       LOG_PRINT_L2("on_transfer_split called create_transactions_2");
 
+      if (ptx_vector.empty())
+      {
+        er.code = WALLET_RPC_ERROR_CODE_TX_NOT_POSSIBLE;
+        er.message = "No transaction created";
+        return false;
+      }
+
       return fill_response(ptx_vector, req.get_tx_keys, res.tx_key_list, res.amount_list, res.fee_list, res.multisig_txset, res.unsigned_txset, req.do_not_relay,
           res.tx_hash_list, req.get_tx_hex, res.tx_blob_list, req.get_tx_metadata, res.tx_metadata_list, er);
     }