rpc: Limit echo to 10 args

src/rpc/misc.cpp

@@ -583,16 +583,29 @@ 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"
+                "\nIt will return an internal bug report when arg9='trigger_internal_bug' is 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.",
-                {},
+                {
+                    {"arg0", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg1", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg2", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg3", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg4", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg5", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg6", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg7", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg8", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                    {"arg9", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, ""},
+                },
                 RPCResult{RPCResult::Type::NONE, "", "Returns whatever was passed in"},
                 RPCExamples{""},
             }.ToString()
         );
 
-    CHECK_NONFATAL(request.params.size() != 100);
+    if (request.params[9].isStr()) {
+        CHECK_NONFATAL(request.params[9].get_str() != "trigger_internal_bug");
+    }
 
     return request.params;
 }

test/functional/rpc_misc.py

@@ -27,8 +27,8 @@ class RpcMiscTest(BitcoinTestFramework):
         self.log.info("test CHECK_NONFATAL")
         assert_raises_rpc_error(
             -1,
-            "Internal bug detected: 'request.params.size() != 100'",
-            lambda: node.echo(*[0] * 100),
+            'Internal bug detected: \'request.params[9].get_str() != "trigger_internal_bug"\'',
+            lambda: node.echo(arg9='trigger_internal_bug'),
         )
 
         self.log.info("test getmemoryinfo")