wallet: Use IsValidNumArgs in getwalletinfo rpc

src/wallet/rpcwallet.cpp

@@ -2382,9 +2382,7 @@ static UniValue getwalletinfo(const JSONRPCRequest& request)
         return NullUniValue;
     }
 
-    if (request.fHelp || request.params.size() != 0)
+    const RPCHelpMan help{"getwalletinfo",
-        throw std::runtime_error(
-            RPCHelpMan{"getwalletinfo",
                 "Returns an object containing various wallet state info.\n",
                 {},
                 RPCResult{
@@ -2408,7 +2406,11 @@ static UniValue getwalletinfo(const JSONRPCRequest& request)
                     HelpExampleCli("getwalletinfo", "")
             + HelpExampleRpc("getwalletinfo", "")
                 },
-            }.ToString());
+    };
+
+    if (request.fHelp || !help.IsValidNumArgs(request.params.size())) {
+        throw std::runtime_error(help.ToString());
+    }
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now