Merge pull request #270 from bas080/feat/set-day-of-week

Add setting the day of the week

Author: iamkun

src/index.js

@@ -195,6 +195,9 @@ class Dayjs {
   $set(units, int) { // private set
     const unit = Utils.prettyUnit(units)
     switch (unit) {
+      case C.D:
+        Utils.setDay(this.$d, int)
+        break
       case C.DATE:
         this.$d.setDate(int)
         break

src/utils.js

@@ -40,7 +40,17 @@ const prettyUnit = (u) => {
 
 const isUndefined = s => s === undefined
 
+const setDay = (date, day) => {
+  const currentDay = date.getDay()
+  const distance = day - currentDay
+
+  date.setDate(date.getDate() + distance)
+
+  return date
+}
+
 export default {
+  setDay,
   padStart,
   padZoneStr,
   monthDiff,

test/get-set.test.js

@@ -46,6 +46,10 @@ it('Set Day', () => {
   expect(dayjs().set('date', 30).valueOf()).toBe(moment().set('date', 30).valueOf())
 })
 
+it('Set Day of Week', () => {
+  expect(dayjs().set('day', 0).valueOf()).toBe(moment().set('day', 0).valueOf())
+})
+
 it('Set Month', () => {
   expect(dayjs().set('month', 11).valueOf()).toBe(moment().set('month', 11).valueOf())
 })

test/utils.test.js

@@ -26,3 +26,9 @@ it('PadStart', () => {
   expect(padStart(1, 2, '0')).toBe('01')
   expect(padStart(0, 2, '0')).toBe('00')
 })
+
+it('SetDate', () => {
+  const day = Math.floor((Math.random() * 7) % 6)
+
+  expect(Utils.setDay((new Date()), day).getDay()).toBe(day)
+})