message: rpc: decodescript use IsValidNumArgs over hardcoded check
diff: @@ -610,9 +610,7 @@ static UniValue decoderawtransaction(const JSONRPCRequest& request)
  static UniValue decodescript(const JSONRPCRequest& request)
  {
  - if (request.fHelp || request.params.size() != 1)
  - throw std::runtime_error(
  - RPCHelpMan{"decodescript",
  + const RPCHelpMan help{"decodescript",
  "\nDecode a hex-encoded script.\n",
  {
  {"hexstring", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "the hex-encoded script"},
  @@ -643,7 +641,11 @@ static UniValue decodescript(const JSONRPCRequest& request)
  HelpExampleCli("decodescript", "\"hexstring\"")
  + HelpExampleRpc("decodescript", "\"hexstring\"")
  },
  - }.ToString());
  + };
  +
  + if (request.fHelp || !help.IsValidNumArgs(request.params.size())) {
  + throw std::runtime_error(help.ToString());
  + }
  RPCTypeCheck(request.params, {UniValue::VSTR});
  