util: Add CHECK_NONFATAL and use it in src/rpc

src/rpc/misc.cpp

@@ -3,15 +3,16 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-#include <key_io.h>
 #include <httpserver.h>
+#include <key_io.h>
 #include <outputtype.h>
 #include <rpc/blockchain.h>
 #include <rpc/server.h>
 #include <rpc/util.h>
 #include <script/descriptor.h>
-#include <util/system.h>
+#include <util/check.h>
 #include <util/strencodings.h>
+#include <util/system.h>
 #include <util/validation.h>
 
 #include <stdint.h>
@@ -540,6 +541,7 @@ static UniValue echo(const JSONRPCRequest& request)
         throw std::runtime_error(
             RPCHelpMan{"echo|echojson ...",
                 "\nSimply echo back the input arguments. This command is for testing.\n"
+                "\nIt will return an internal bug report when exactly 100 arguments are passed.\n"
                 "\nThe difference between echo and echojson is that echojson has argument conversion enabled in the client-side table in "
                 "bitcoin-cli and the GUI. There is no server-side difference.",
                 {},
@@ -548,6 +550,8 @@ static UniValue echo(const JSONRPCRequest& request)
             }.ToString()
         );
 
+    CHECK_NONFATAL(request.params.size() != 100);
+
     return request.params;
 }