f_test_garbagecollect_now(typval_T *argvars UNUSED, typval_T *rettv UNUSED)
{
    // This is dangerous, any Lists and Dicts used internally may be freed
    // while still in use.
    if (!get_vim_var_nr(VV_TESTING))
	emsg(_(e_calling_test_garbagecollect_now_while_v_testing_is_not_set));
    else
	garbage_collect(TRUE);
}