layui 日期初化一个月前

lay('.test-item').each(function(){
  var d = new Date();
  laydate.render({
    elem: this
    ,max: 0
    ,value: d.getFullYear() + '-' + lay.digit(d.getMonth() + 1) + '-' + lay.digit(d.getDate())
    ,trigger: 'click'
  });
});