From e173abbe7297968db158efacf75971b4c832881a Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Thu, 19 Apr 2018 17:14:27 +0800
Subject: [PATCH 01/12] style(moment style): moment style

---
 src/index.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/index.js b/src/index.js
index 596076d5d..2a9759168 100644
--- a/src/index.js
+++ b/src/index.js
@@ -193,10 +193,10 @@ class Dayjs {
     })
   }
 
-  diff(otherDate, unit, float = false) {
-    const other = otherDate instanceof Dayjs ? otherDate : new Dayjs(otherDate)
-    const diff = this - other
-    let result = Utils.monthDiff(this, other)
+  diff(input, unit, float = false) {
+    const that = input instanceof Dayjs ? input : new Dayjs(input)
+    const diff = this - that
+    let result = Utils.monthDiff(this, that)
     switch (unit) {
       case 'years':
         result /= 12

From b56a83b5aa09e1d6167906766f56f80f248f05a0 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Thu, 19 Apr 2018 17:43:48 +0800
Subject: [PATCH 02/12] style(modern): modern

---
 src/constant.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/constant.js b/src/constant.js
index 989142820..88c63d773 100644
--- a/src/constant.js
+++ b/src/constant.js
@@ -3,7 +3,7 @@ export const SECONDS_A_HOUR = SECONDS_A_MINUTE * 60
 export const SECONDS_A_DAY = SECONDS_A_HOUR * 24
 export const SECONDS_A_WEEK = SECONDS_A_DAY * 7
 
-export const MILLISECONDS_A_SECOND = 1000
+export const MILLISECONDS_A_SECOND = 1e3
 export const MILLISECONDS_A_MINUTE = SECONDS_A_MINUTE * MILLISECONDS_A_SECOND
 export const MILLISECONDS_A_HOUR = SECONDS_A_HOUR * MILLISECONDS_A_SECOND
 export const MILLISECONDS_A_DAY = SECONDS_A_DAY * MILLISECONDS_A_SECOND

From c702be8ecaa7ddb163975b9f53b40c1b716c58f8 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Thu, 19 Apr 2018 18:32:01 +0800
Subject: [PATCH 03/12] build(rename): rename build dist file name

---
 rollup.config.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/rollup.config.js b/rollup.config.js
index 00b49f670..6a1fc4d54 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -1,10 +1,11 @@
 import babel from 'rollup-plugin-babel'
 import uglify from 'rollup-plugin-uglify'
+import packageInfo from './package.json';
 
 export default {
   input: 'src/index.js',
   output: {
-    file: 'dist/index.js',
+    file: `dist/${packageInfo.name}.min.js`,
     format: 'umd',
     name: 'dayjs'
   },

From bdc33b2ce392194b91f70a04161616bcc9ca8bdb Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 09:43:16 +0800
Subject: [PATCH 04/12] fix(immutable): immutable set

---
 src/index.js         | 14 ++++++++------
 test/get-set.test.js | 15 +++++++++++++--
 test/parse.test.js   |  9 ++++-----
 3 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/src/index.js b/src/index.js
index 2a9759168..69f11b0d4 100644
--- a/src/index.js
+++ b/src/index.js
@@ -96,8 +96,7 @@ class Dayjs {
     return this.startOf(arg, false)
   }
 
-  set(string, int) {
-    if (!Utils.isNumber(int)) return this
+  mSet(string, int) {
     switch (string) {
       case 'date':
         this.$date.setDate(int)
@@ -115,12 +114,15 @@ class Dayjs {
     return this
   }
 
+  set(string, int) {
+    if (!Utils.isNumber(int)) return this
+    return this.clone().mSet(string, int)
+  }
+
   add(number, string) {
     if (['M', 'months'].indexOf(string) > -1) {
-      const date = this.clone()
-      date.set('date', 1)
-      date.set('month', this.month() + number)
-      date.set('date', Math.min(this.date(), date.daysInMonth()))
+      let date = this.set('date', 1).set('month', this.month() + number)
+      date = date.set('date', Math.min(this.date(), date.daysInMonth()))
       return date
     }
     let step
diff --git a/test/get-set.test.js b/test/get-set.test.js
index f6ca4ed97..b09ae1acf 100644
--- a/test/get-set.test.js
+++ b/test/get-set.test.js
@@ -23,12 +23,23 @@ it('Date', () => {
 })
 
 it('Set Unknown String', () => {
-  expect(dayjs().set('Unknown String', 1).unix())
+  const newDate = dayjs().set('Unknown String', 1)
+  expect(newDate.unix())
     .toBe(moment().set('Unknown String', 1).unix())
 })
 
 it('Set Not Int', () => {
-  expect(dayjs().set('year', 'Not Int').unix())
+  const newDate = dayjs().set('year', 'Not Int')
+  expect(newDate.unix())
     .toBe(moment().set('year', 'Not Int').unix())
 })
 
+it('Immutable Set', () => {
+  const dayjsA = dayjs()
+  const dayjsB = dayjsA.set('year', 2011)
+  const momentA = moment()
+  const momentB = momentA.set('year', 2011)
+  expect(dayjsA.unix()).not.toBe(dayjsB.unix())
+  expect(momentA.unix()).toBe(momentB.unix())
+})
+
diff --git a/test/parse.test.js b/test/parse.test.js
index 3dcd27c1e..0b26fd2e0 100644
--- a/test/parse.test.js
+++ b/test/parse.test.js
@@ -37,15 +37,14 @@ it('Unix Timestamp Number (milliseconds) 1523520536000', () => {
 it('Clone not affect each other', () => {
   const base = dayjs(20170101)
   const year = base.year()
-  const another = base.clone()
-  another.set('year', year + 1)
+  const another = base.set('year', year + 1)
   expect(another.unix() - base.unix()).toBe(31536000)
 })
 
 it('Clone with same value', () => {
   const base = dayjs()
   const year = base.year()
-  base.set('year', year + 1)
-  const another = base.clone()
-  expect(base.toString()).toBe(another.toString())
+  const newBase = base.set('year', year + 1)
+  const another = newBase.clone()
+  expect(newBase.toString()).toBe(another.toString())
 })

From a9f2694ba8ae38867976401c2f2b50dd2360c97b Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 09:46:16 +0800
Subject: [PATCH 05/12] style(short): short

---
 src/index.js | 58 ++++++++++++++++++++++++++--------------------------
 1 file changed, 29 insertions(+), 29 deletions(-)

diff --git a/src/index.js b/src/index.js
index 69f11b0d4..0ee59e8a7 100644
--- a/src/index.js
+++ b/src/index.js
@@ -23,42 +23,42 @@ class Dayjs {
   init() {
     this.timeZone = this.$date.getTimezoneOffset() / 60
     this.timeZoneString = Utils.padStart(String(this.timeZone * -1).replace(/^(.)?(\d)/, '$10$200'), 5, '+')
-    this.$year = this.$date.getFullYear()
-    this.$month = this.$date.getMonth()
-    this.$day = this.$date.getDate()
-    this.$week = this.$date.getDay()
-    this.$hour = this.$date.getHours()
-    this.$minute = this.$date.getMinutes()
-    this.$second = this.$date.getSeconds()
-    this.$milliseconds = this.$date.getMilliseconds()
+    this.$y = this.$date.getFullYear()
+    this.$M = this.$date.getMonth()
+    this.$D = this.$date.getDate()
+    this.$W = this.$date.getDay()
+    this.$H = this.$date.getHours()
+    this.$m = this.$date.getMinutes()
+    this.$s = this.$date.getSeconds()
+    this.$ms = this.$date.getMilliseconds()
   }
 
   year() {
-    return this.$year
+    return this.$y
   }
 
   month() {
-    return this.$month
+    return this.$M
   }
 
   date() {
-    return this.$day
+    return this.$D
   }
 
   hour() {
-    return this.$hour
+    return this.$H
   }
 
   minute() {
-    return this.$minute
+    return this.$m
   }
 
   second() {
-    return this.$second
+    return this.$s
   }
 
   millisecond() {
-    return this.$milliseconds
+    return this.$ms
   }
 
   unix() {
@@ -160,33 +160,33 @@ class Dayjs {
     return formatStr.replace(/Y{2,4}|M{1,2}|D{1,2}|d{1,4}|H{1,2}|m{1,2}|s{1,2}|Z{1,2}/g, (match) => {
       switch (match) {
         case 'YY':
-          return String(this.$year).slice(-2)
+          return String(this.$y).slice(-2)
         case 'YYYY':
-          return String(this.$year)
+          return String(this.$y)
         case 'M':
-          return String(this.$month + 1)
+          return String(this.$M + 1)
         case 'MM':
-          return Utils.padStart(String(this.$month + 1), 2, '0')
+          return Utils.padStart(String(this.$M + 1), 2, '0')
         case 'D':
-          return String(this.$day)
+          return String(this.$D)
         case 'DD':
-          return Utils.padStart(String(this.$day), 2, '0')
+          return Utils.padStart(String(this.$D), 2, '0')
         case 'd':
-          return String(this.$week)
+          return String(this.$W)
         case 'dddd':
-          return weeks[this.$week]
+          return weeks[this.$W]
         case 'H':
-          return String(this.$hour)
+          return String(this.$H)
         case 'HH':
-          return Utils.padStart(String(this.$hour), 2, '0')
+          return Utils.padStart(String(this.$H), 2, '0')
         case 'm':
-          return String(this.$minute)
+          return String(this.$m)
         case 'mm':
-          return Utils.padStart(String(this.$minute), 2, '0')
+          return Utils.padStart(String(this.$m), 2, '0')
         case 's':
-          return String(this.$second)
+          return String(this.$s)
         case 'ss':
-          return Utils.padStart(String(this.$second), 2, '0')
+          return Utils.padStart(String(this.$s), 2, '0')
         case 'Z':
           return `${this.timeZoneString.slice(0, -2)}:00`
         default: // 'ZZ'

From a59353e8dbf575738f3a770842a6086e109b7ea6 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 09:47:10 +0800
Subject: [PATCH 06/12] style(short): short date

---
 src/index.js | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/index.js b/src/index.js
index 0ee59e8a7..e120e7419 100644
--- a/src/index.js
+++ b/src/index.js
@@ -16,21 +16,21 @@ const parseConfig = (config) => {
 
 class Dayjs {
   constructor(config) {
-    this.$date = parseConfig(config)
+    this.$d = parseConfig(config)
     this.init()
   }
 
   init() {
-    this.timeZone = this.$date.getTimezoneOffset() / 60
+    this.timeZone = this.$d.getTimezoneOffset() / 60
     this.timeZoneString = Utils.padStart(String(this.timeZone * -1).replace(/^(.)?(\d)/, '$10$200'), 5, '+')
-    this.$y = this.$date.getFullYear()
-    this.$M = this.$date.getMonth()
-    this.$D = this.$date.getDate()
-    this.$W = this.$date.getDay()
-    this.$H = this.$date.getHours()
-    this.$m = this.$date.getMinutes()
-    this.$s = this.$date.getSeconds()
-    this.$ms = this.$date.getMilliseconds()
+    this.$y = this.$d.getFullYear()
+    this.$M = this.$d.getMonth()
+    this.$D = this.$d.getDate()
+    this.$W = this.$d.getDay()
+    this.$H = this.$d.getHours()
+    this.$m = this.$d.getMinutes()
+    this.$s = this.$d.getSeconds()
+    this.$ms = this.$d.getMilliseconds()
   }
 
   year() {
@@ -67,7 +67,7 @@ class Dayjs {
 
   valueOf() {
     // timezone(hour) * 60 * 60 * 1000 => ms
-    return this.$date.getTime()
+    return this.$d.getTime()
   }
 
   startOf(arg, isStartOf = true) {
@@ -99,13 +99,13 @@ class Dayjs {
   mSet(string, int) {
     switch (string) {
       case 'date':
-        this.$date.setDate(int)
+        this.$d.setDate(int)
         break
       case 'month':
-        this.$date.setMonth(int)
+        this.$d.setMonth(int)
         break
       case 'year':
-        this.$date.setFullYear(int)
+        this.$d.setFullYear(int)
         break
       default:
         break
@@ -232,7 +232,7 @@ class Dayjs {
   }
 
   toDate() {
-    return new Date(this.$date)
+    return new Date(this.$d)
   }
 
   toArray() {
@@ -268,7 +268,7 @@ class Dayjs {
   }
 
   toString() {
-    return this.$date.toUTCString()
+    return this.$d.toUTCString()
   }
 }
 

From 99e569a4df66dc456db18bd6a50761d0518f804b Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 10:01:03 +0800
Subject: [PATCH 07/12] refactor(format): format units

---
 src/constant.js         | 11 +++++++
 src/index.js            | 70 ++++++++++++++++++++++-------------------
 src/utils.js            |  1 +
 test/manipulate.test.js |  4 +--
 4 files changed, 51 insertions(+), 35 deletions(-)

diff --git a/src/constant.js b/src/constant.js
index 88c63d773..b64692a78 100644
--- a/src/constant.js
+++ b/src/constant.js
@@ -8,3 +8,14 @@ export const MILLISECONDS_A_MINUTE = SECONDS_A_MINUTE * MILLISECONDS_A_SECOND
 export const MILLISECONDS_A_HOUR = SECONDS_A_HOUR * MILLISECONDS_A_SECOND
 export const MILLISECONDS_A_DAY = SECONDS_A_DAY * MILLISECONDS_A_SECOND
 export const MILLISECONDS_A_WEEK = SECONDS_A_WEEK * MILLISECONDS_A_SECOND
+
+export const MS = 'millisecond'
+export const S = 'second'
+export const MIN = 'minute'
+export const H = 'hour'
+export const D = 'day'
+export const W = 'week'
+export const M = 'month'
+export const Q = 'quarter'
+export const Y = 'year'
+export const DATE = 'date'
diff --git a/src/index.js b/src/index.js
index e120e7419..ab407ed2a 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,4 +1,4 @@
-import * as Constant from './constant'
+import * as C from './constant'
 import * as Utils from './utils'
 
 const parseConfig = (config) => {
@@ -70,19 +70,20 @@ class Dayjs {
     return this.$d.getTime()
   }
 
-  startOf(arg, isStartOf = true) {
-    switch (arg) {
-      case 'year':
+  startOf(units, isStartOf = true) {
+    const unit = Utils.prettyUnit(units)
+    switch (unit) {
+      case C.Y:
         if (isStartOf) {
           return new Dayjs(new Date(this.year(), 0, 1))
         }
         return new Dayjs(new Date(this.year(), 11, 31)).endOf('day')
-      case 'month':
+      case C.M:
         if (isStartOf) {
           return new Dayjs(new Date(this.year(), this.month(), 1))
         }
         return new Dayjs(new Date(this.year(), this.month() + 1, 0)).endOf('day')
-      case 'day':
+      case C.D:
         if (isStartOf) {
           return new Dayjs(this.toDate().setHours(0, 0, 0, 0))
         }
@@ -96,15 +97,16 @@ class Dayjs {
     return this.startOf(arg, false)
   }
 
-  mSet(string, int) {
-    switch (string) {
-      case 'date':
+  mSet(units, int) {
+    const unit = Utils.prettyUnit(units)
+    switch (unit) {
+      case C.DATE:
         this.$d.setDate(int)
         break
-      case 'month':
+      case C.M:
         this.$d.setMonth(int)
         break
-      case 'year':
+      case C.Y:
         this.$d.setFullYear(int)
         break
       default:
@@ -119,32 +121,33 @@ class Dayjs {
     return this.clone().mSet(string, int)
   }
 
-  add(number, string) {
-    if (['M', 'months'].indexOf(string) > -1) {
+  add(number, units) {
+    const unit = (units && units.length === 1) ? units : Utils.prettyUnit(units)
+    if (['M', C.M].indexOf(unit) > -1) {
       let date = this.set('date', 1).set('month', this.month() + number)
       date = date.set('date', Math.min(this.date(), date.daysInMonth()))
       return date
     }
     let step
-    switch (string) {
+    switch (unit) {
       case 'm':
-      case 'minutes':
-        step = Constant.MILLISECONDS_A_MINUTE
+      case C.MIN:
+        step = C.MILLISECONDS_A_MINUTE
         break
       case 'h':
-      case 'hours':
-        step = Constant.MILLISECONDS_A_HOUR
+      case C.H:
+        step = C.MILLISECONDS_A_HOUR
         break
       case 'd':
-      case 'days':
-        step = Constant.MILLISECONDS_A_DAY
+      case C.D:
+        step = C.MILLISECONDS_A_DAY
         break
       case 'w':
-      case 'weeks':
-        step = Constant.MILLISECONDS_A_WEEK
+      case C.W:
+        step = C.MILLISECONDS_A_WEEK
         break
       default: // s seconds
-        step = Constant.MILLISECONDS_A_SECOND
+        step = C.MILLISECONDS_A_SECOND
     }
     const nextTimeStamp = this.valueOf() + (number * step)
     return new Dayjs(nextTimeStamp)
@@ -195,27 +198,28 @@ class Dayjs {
     })
   }
 
-  diff(input, unit, float = false) {
+  diff(input, units, float = false) {
+    const unit = Utils.prettyUnit(units)
     const that = input instanceof Dayjs ? input : new Dayjs(input)
     const diff = this - that
     let result = Utils.monthDiff(this, that)
     switch (unit) {
-      case 'years':
+      case C.Y:
         result /= 12
         break
-      case 'months':
+      case C.M:
         break
-      case 'quarters':
+      case C.Q:
         result /= 3
         break
-      case 'weeks':
-        result = diff / Constant.MILLISECONDS_A_WEEK
+      case C.W:
+        result = diff / C.MILLISECONDS_A_WEEK
         break
-      case 'days':
-        result = diff / Constant.MILLISECONDS_A_DAY
+      case C.D:
+        result = diff / C.MILLISECONDS_A_DAY
         break
-      case 'seconds':
-        result = diff / Constant.MILLISECONDS_A_SECOND
+      case C.S:
+        result = diff / C.MILLISECONDS_A_SECOND
         break
       default: // milliseconds
         result = diff
diff --git a/src/utils.js b/src/utils.js
index b78429ef4..37901154a 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -23,3 +23,4 @@ export const monthDiff = (a, b) => {
 
 export const absFloor = n => (n < 0 ? Math.ceil(n) || 0 : Math.floor(n))
 
+export const prettyUnit = u => (u && String(u).toLowerCase().replace(/s$/, ''))
diff --git a/test/manipulate.test.js b/test/manipulate.test.js
index a079b6b3d..fff7867a8 100644
--- a/test/manipulate.test.js
+++ b/test/manipulate.test.js
@@ -10,8 +10,8 @@ afterEach(() => {
   MockDate.reset()
 })
 
-it('StartOf EndOf Year', () => {
-  expect(dayjs().startOf('year').unix()).toBe(moment().startOf('year').unix())
+it('StartOf EndOf Year with s and upper case', () => {
+  expect(dayjs().startOf('YearS').unix()).toBe(moment().startOf('year').unix())
   expect(dayjs().endOf('year').unix()).toBe(moment().endOf('year').unix())
 })
 

From 21100390ea6620ed73dde207460efe9dc955d8c1 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 10:20:36 +0800
Subject: [PATCH 08/12] fix(isValid): add isValid

---
 src/index.js       | 4 ++++
 test/parse.test.js | 6 ++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/index.js b/src/index.js
index ab407ed2a..4cbda118e 100644
--- a/src/index.js
+++ b/src/index.js
@@ -33,6 +33,10 @@ class Dayjs {
     this.$ms = this.$d.getMilliseconds()
   }
 
+  isValid() {
+    return !(this.$d.toString() === 'Invalid Date')
+  }
+
   year() {
     return this.$y
   }
diff --git a/test/parse.test.js b/test/parse.test.js
index 0b26fd2e0..f8530c353 100644
--- a/test/parse.test.js
+++ b/test/parse.test.js
@@ -18,14 +18,16 @@ describe('Parse', () => {
     expect(dayjs('20130208').unix()).toBe(moment('20130208').unix())
   })
 
-  it('String ISO 8601 date, time and zone ', () => {
+  it('String ISO 8601 date, time and zone', () => {
     const time = '2018-04-04T16:00:00.000Z'
     expect(dayjs(time).unix()).toBe(moment(time).unix())
   })
 
-  it('String Other', () => {
+  it('String Other and isValid', () => {
     global.console.warn = jest.genMockFunction()// moment.js otherString will throw warn
     expect(dayjs('otherString').toString().toLowerCase()).toBe(moment('otherString').toString().toLowerCase())
+    expect(dayjs().isValid()).toBe(true)
+    expect(dayjs('otherString').isValid()).toBe(false)
   })
 })
 

From 1ad0b464dbc30c7baea62970a192fc4c874f9155 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 10:37:09 +0800
Subject: [PATCH 09/12] fix(add year): add add year

---
 src/index.js            | 9 ++++++---
 test/manipulate.test.js | 1 +
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/index.js b/src/index.js
index 4cbda118e..240d0838d 100644
--- a/src/index.js
+++ b/src/index.js
@@ -74,7 +74,7 @@ class Dayjs {
     return this.$d.getTime()
   }
 
-  startOf(units, isStartOf = true) {
+  startOf(units, isStartOf = true) { // isStartOf -> endOf
     const unit = Utils.prettyUnit(units)
     switch (unit) {
       case C.Y:
@@ -128,10 +128,13 @@ class Dayjs {
   add(number, units) {
     const unit = (units && units.length === 1) ? units : Utils.prettyUnit(units)
     if (['M', C.M].indexOf(unit) > -1) {
-      let date = this.set('date', 1).set('month', this.month() + number)
-      date = date.set('date', Math.min(this.date(), date.daysInMonth()))
+      let date = this.set(C.DATE, 1).set(C.M, this.month() + number)
+      date = date.set(C.DATE, Math.min(this.date(), date.daysInMonth()))
       return date
     }
+    if (['y', C.Y].indexOf(unit) > -1) {
+      return this.set(C.Y, this.year() + number)
+    }
     let step
     switch (unit) {
       case 'm':
diff --git a/test/manipulate.test.js b/test/manipulate.test.js
index fff7867a8..1b4c9acb3 100644
--- a/test/manipulate.test.js
+++ b/test/manipulate.test.js
@@ -42,6 +42,7 @@ it('Add Time days', () => {
   expect(dayjs().add(1, 'd').unix()).toBe(moment().add(1, 'd').unix())
   expect(dayjs().add(1, 'days').unix()).toBe(moment().add(1, 'days').unix())
   expect(dayjs().add(1, 'M').unix()).toBe(moment().add(1, 'M').unix())
+  expect(dayjs().add(1, 'y').unix()).toBe(moment().add(1, 'y').unix())
   expect(dayjs('20111031').add(1, 'months').unix()).toBe(moment('20111031').add(1, 'months').unix())
 })
 

From 871011c44cd69d10b0045f6fcafc10a5bf148484 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 10:55:21 +0800
Subject: [PATCH 10/12] refactor(short): short

---
 src/index.js         | 48 ++++++++++++++++++++++++--------------------
 test/get-set.test.js | 16 +++++++++++++++
 test/query.test.js   | 16 +++++++++++++++
 3 files changed, 58 insertions(+), 22 deletions(-)
 create mode 100644 test/query.test.js

diff --git a/src/index.js b/src/index.js
index 240d0838d..f66ca29bf 100644
--- a/src/index.js
+++ b/src/index.js
@@ -37,6 +37,10 @@ class Dayjs {
     return !(this.$d.toString() === 'Invalid Date')
   }
 
+  isLeapYear() {
+    return ((this.$y % 4 === 0) && (this.$y % 100 !== 0)) || (this.$y % 400 === 0)
+  }
+
   year() {
     return this.$y
   }
@@ -79,14 +83,14 @@ class Dayjs {
     switch (unit) {
       case C.Y:
         if (isStartOf) {
-          return new Dayjs(new Date(this.year(), 0, 1))
+          return new Dayjs(new Date(this.$y, 0, 1))
         }
-        return new Dayjs(new Date(this.year(), 11, 31)).endOf('day')
+        return new Dayjs(new Date(this.$y, 11, 31)).endOf('day')
       case C.M:
         if (isStartOf) {
-          return new Dayjs(new Date(this.year(), this.month(), 1))
+          return new Dayjs(new Date(this.$y, this.$M, 1))
         }
-        return new Dayjs(new Date(this.year(), this.month() + 1, 0)).endOf('day')
+        return new Dayjs(new Date(this.$y, this.$M + 1, 0)).endOf('day')
       case C.D:
         if (isStartOf) {
           return new Dayjs(this.toDate().setHours(0, 0, 0, 0))
@@ -128,12 +132,12 @@ class Dayjs {
   add(number, units) {
     const unit = (units && units.length === 1) ? units : Utils.prettyUnit(units)
     if (['M', C.M].indexOf(unit) > -1) {
-      let date = this.set(C.DATE, 1).set(C.M, this.month() + number)
-      date = date.set(C.DATE, Math.min(this.date(), date.daysInMonth()))
+      let date = this.set(C.DATE, 1).set(C.M, this.$M + number)
+      date = date.set(C.DATE, Math.min(this.$D, date.daysInMonth()))
       return date
     }
     if (['y', C.Y].indexOf(unit) > -1) {
-      return this.set(C.Y, this.year() + number)
+      return this.set(C.Y, this.$y + number)
     }
     let step
     switch (unit) {
@@ -235,7 +239,7 @@ class Dayjs {
   }
 
   daysInMonth() {
-    return this.endOf('month').date()
+    return this.endOf(C.M).$D
   }
 
   clone() {
@@ -248,13 +252,13 @@ class Dayjs {
 
   toArray() {
     return [
-      this.year(),
-      this.month(),
-      this.date(),
-      this.hour(),
-      this.minute(),
-      this.second(),
-      this.millisecond()
+      this.$y,
+      this.$M,
+      this.$D,
+      this.$H,
+      this.$m,
+      this.$s,
+      this.$ms
     ]
   }
 
@@ -268,13 +272,13 @@ class Dayjs {
 
   toObject() {
     return {
-      years: this.year(),
-      months: this.month(),
-      date: this.date(),
-      hours: this.hour(),
-      minutes: this.minute(),
-      seconds: this.second(),
-      milliseconds: this.millisecond()
+      years: this.$y,
+      months: this.$M,
+      date: this.$D,
+      hours: this.$H,
+      minutes: this.$m,
+      seconds: this.$s,
+      milliseconds: this.$ms
     }
   }
 
diff --git a/test/get-set.test.js b/test/get-set.test.js
index b09ae1acf..35a738650 100644
--- a/test/get-set.test.js
+++ b/test/get-set.test.js
@@ -22,6 +22,22 @@ it('Date', () => {
   expect(dayjs().date()).toBe(moment().date())
 })
 
+it('Hour', () => {
+  expect(dayjs().hour()).toBe(moment().hour())
+})
+
+it('Minute', () => {
+  expect(dayjs().minute()).toBe(moment().minute())
+})
+
+it('Second', () => {
+  expect(dayjs().second()).toBe(moment().second())
+})
+
+it('Millisecond', () => {
+  expect(dayjs().millisecond()).toBe(moment().millisecond())
+})
+
 it('Set Unknown String', () => {
   const newDate = dayjs().set('Unknown String', 1)
   expect(newDate.unix())
diff --git a/test/query.test.js b/test/query.test.js
new file mode 100644
index 000000000..f2cbe050a
--- /dev/null
+++ b/test/query.test.js
@@ -0,0 +1,16 @@
+// import moment from 'moment'
+import MockDate from 'mockdate'
+import dayjs from '../src'
+
+beforeEach(() => {
+  MockDate.set(new Date())
+})
+
+afterEach(() => {
+  MockDate.reset()
+})
+
+it('IsLeapYear', () => {
+  expect(dayjs('20000101').isLeapYear()).toBe(true)
+  expect(dayjs('21000101').isLeapYear()).toBe(false)
+})

From 5a0a6ffbf10761bd8b4b90298281265a0cebdbc2 Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 11:03:59 +0800
Subject: [PATCH 11/12] fix(add): add isBefore isAfter isSame

---
 src/index.js       | 12 ++++++++++++
 test/query.test.js | 13 ++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/index.js b/src/index.js
index f66ca29bf..5af04c3ec 100644
--- a/src/index.js
+++ b/src/index.js
@@ -41,6 +41,18 @@ class Dayjs {
     return ((this.$y % 4 === 0) && (this.$y % 100 !== 0)) || (this.$y % 400 === 0)
   }
 
+  isSame(that) {
+    return this.valueOf() === that.valueOf()
+  }
+
+  isBefore(that) {
+    return this.valueOf() < that.valueOf()
+  }
+
+  isAfter(that) {
+    return this.valueOf() > that.valueOf()
+  }
+
   year() {
     return this.$y
   }
diff --git a/test/query.test.js b/test/query.test.js
index f2cbe050a..5b930541c 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1,4 +1,4 @@
-// import moment from 'moment'
+import moment from 'moment'
 import MockDate from 'mockdate'
 import dayjs from '../src'
 
@@ -14,3 +14,14 @@ it('IsLeapYear', () => {
   expect(dayjs('20000101').isLeapYear()).toBe(true)
   expect(dayjs('21000101').isLeapYear()).toBe(false)
 })
+
+it('Is Before Is After Is Same', () => {
+  [moment, dayjs].forEach((instance) => {
+    const dayA = instance()
+    const dayB = dayA.clone().add(1, 'day')
+    const dayC = dayA.clone().subtract(1, 'day')
+    expect(dayC.isBefore(dayA)).toBe(true)
+    expect(dayA.isSame(instance())).toBe(true)
+    expect(dayB.isAfter(dayA)).toBe(true)
+  })
+})

From af83c2609debf52f6e9aa25ea8d318b3337b8c1f Mon Sep 17 00:00:00 2001
From: iamkun <kunhello@outlook.com>
Date: Fri, 20 Apr 2018 11:05:42 +0800
Subject: [PATCH 12/12] test: update test

---
 test/query.test.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/query.test.js b/test/query.test.js
index 5b930541c..15a941b0c 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -10,13 +10,15 @@ afterEach(() => {
   MockDate.reset()
 })
 
+const testArr = [dayjs, moment]
+
 it('IsLeapYear', () => {
   expect(dayjs('20000101').isLeapYear()).toBe(true)
   expect(dayjs('21000101').isLeapYear()).toBe(false)
 })
 
 it('Is Before Is After Is Same', () => {
-  [moment, dayjs].forEach((instance) => {
+  testArr.forEach((instance) => {
     const dayA = instance()
     const dayB = dayA.clone().add(1, 'day')
     const dayC = dayA.clone().subtract(1, 'day')