f_test_alloc_fail(typval_T *argvars, typval_T *rettv UNUSED)
{
    if (in_vim9script()
	    && (check_for_number_arg(argvars, 0) == FAIL
		|| check_for_number_arg(argvars, 1) == FAIL
		|| check_for_number_arg(argvars, 2) == FAIL))
	return;

    if (argvars[0].v_type != VAR_NUMBER
	    || argvars[0].vval.v_number <= 0
	    || argvars[1].v_type != VAR_NUMBER
	    || argvars[1].vval.v_number < 0
	    || argvars[2].v_type != VAR_NUMBER)
	emsg(_(e_invalid_argument));
    else
    {
	alloc_fail_id = argvars[0].vval.v_number;
	if (alloc_fail_id >= aid_last)
	    emsg(_(e_invalid_argument));
	alloc_fail_countdown = argvars[1].vval.v_number;
	alloc_fail_repeat = argvars[2].vval.v_number;
	did_outofmem_msg = FALSE;
    }
}