IsYesterday
IsYesterday adds .isYesterday() API to indicates whether the Day.js object is yesterday or not.
js
var isYesterday = require('dayjs/plugin/isYesterday');
// import isYesterday from 'dayjs/plugin/isYesterday' // ES 2015
dayjs.extend(isYesterday);
dayjs().add(-1, 'day').isYesterday(); // true