cmd: add asserts to b_arglist_report_missing_args

cmd/report.c

@@ -1,5 +1,6 @@
 #include "command.h"
 
+#include <assert.h>
 #include <blue/core/stringstream.h>
 #include <blue/object/string.h>
 #include <blue/term/print.h>
@@ -132,11 +133,13 @@ enum b_status b_arglist_report_missing_args(
 
 	if (opt_id != B_COMMAND_INVALID_ID) {
 		opt = b_command_get_option_with_id(args->list_command, opt_id);
+		assert(opt);
 	}
 
 	if (arg_id != B_COMMAND_INVALID_ID) {
 		arg = opt ? b_command_option_get_arg_with_id(opt, arg_id)
 		          : b_command_get_arg_with_id(args->list_command, arg_id);
+		assert(arg);
 	}
 
 	struct b_string *usage = z__b_command_default_usage_string(