RPC/Blockchain: Clarify invalid-action error in scanblocks & scantxoutset

Author: luke-jr

src/rpc/blockchain.cpp

@@ -2205,7 +2205,7 @@ static RPCHelpMan scantxoutset()
         result.pushKV("unspents", unspents);
         result.pushKV("total_amount", ValueFromAmount(total_in));
     } else {
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid command");
+        throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid action '%s'", request.params[0].get_str()));
     }
     return result;
 },
@@ -2402,7 +2402,7 @@ static RPCHelpMan scanblocks()
         ret.pushKV("relevant_blocks", blocks);
     }
     else {
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid command");
+        throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid action '%s'", request.params[0].get_str()));
     }
     return ret;
 },

test/functional/rpc_scanblocks.py

@@ -122,7 +122,7 @@ def run_test(self):
         assert_equal(node.scanblocks("abort"), False)
 
         # test invalid command
-        assert_raises_rpc_error(-8, "Invalid command", node.scanblocks, "foobar")
+        assert_raises_rpc_error(-8, "Invalid action 'foobar'", node.scanblocks, "foobar")
 
 
 if __name__ == '__main__':