fix: Fix QuarterOfYear plugin bug (#591)

Author: iamkun

src/plugin/quarterOfYear/index.js

@@ -4,7 +4,7 @@ export default (o, c) => {
   const proto = c.prototype
   proto.quarter = function (quarter) {
     if (!this.$utils().u(quarter)) {
-      return this.add((quarter - 1) * 3, M)
+      return this.month((this.month() % 3) + ((quarter - 1) * 3))
     }
     return Math.ceil((this.month() + 1) / 3)
   }

test/plugin/quarterOfYear.test.js

@@ -31,6 +31,9 @@ it('set QuarterOfYear', () => {
   const d2 = '2013-02-05T05:06:07.000'
   expect(dayjs(d2).quarter(2).format())
     .toBe(moment(d2).quarter(2).format())
+  const d3 = '2018-11-25T05:06:07.000'
+  expect(dayjs(d3).quarter(3).format())
+    .toBe(moment(d3).quarter(3).format())
 })
 
 it('add subtract quarter', () => {