js日期加一年

var date=new Date('2021-12-7');
date.setFullYear(date.getFullYear()+1);

var time = date.toLocaleDateString().split('/').join('-')
alert(time);    //2022-12-7

date.setDate(date.getDate()+1);
var time1 = date.toLocaleDateString().split('/').join('-')
alert(time1);    //2022-12-6