iamkun · Dec 19, 2019 · Dec 30, 2019 · Dec 30, 2019 · Jan 6, 2020 · Jan 6, 2020
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,3 +1,15 @@
+## [1.8.19](https://github.com/iamkun/dayjs/compare/v1.8.18...v1.8.19) (2020-01-06)
+
+
+### Bug Fixes
+
+* Add UpdateLocale plugin to update a locale's properties ([#766](https://github.com/iamkun/dayjs/issues/766)) ([82ce2ba](https://github.com/iamkun/dayjs/commit/82ce2ba8d7e402e40f6d005d400eb5356a0b0633))
+* Fix CustomParseFormat Plugin 'YYYY-MM' use first day of the month ([ba709ec](https://github.com/iamkun/dayjs/commit/ba709eca86a71ae648bc68bf67d9abdc229198d4)), closes [#761](https://github.com/iamkun/dayjs/issues/761)
+* Fix CustomParseFormat Plugin to set correct locale ([66ce23f](https://github.com/iamkun/dayjs/commit/66ce23f2e18c5506e8f1a7ef20d3483a4df80087))
+* Fix WeekOfYear Plugin wrong calender week number bug ([79b86db](https://github.com/iamkun/dayjs/commit/79b86dbbf3cfd3f1e2165b3d479a7061ad1b6925)), closes [#760](https://github.com/iamkun/dayjs/issues/760)
+* Update RelativeTime plugin to support function to make additional processing ([#767](https://github.com/iamkun/dayjs/issues/767)) ([4bd9250](https://github.com/iamkun/dayjs/commit/4bd9250fbe7131e2fddfb5fa1b3350e8c2262ca9))
+* Update ru, uk, cs locale to support relativeTime with plural ([3f080f7](https://github.com/iamkun/dayjs/commit/3f080f7d6bfdc4018cbb7c4d0112ff1ead4ef6b8))
+
 ## [1.8.18](https://github.com/iamkun/dayjs/compare/v1.8.17...v1.8.18) (2019-12-18)
 
 

diff --git a/docs/en/API-reference.md b/docs/en/API-reference.md
@@ -514,3 +514,9 @@ plugin [`MinMax`](./Plugin.md#minmax)
 `.calendar` to display calendar time
 
 plugin [`Calendar`](./Plugin.md#calendar)
+
+### UpdateLocale
+
+`.updateLocale` to update a locale's properties
+
+plugin [`UpdateLocale`](./Plugin.md#updateLocale)
diff --git a/docs/en/I18n.md b/docs/en/I18n.md
@@ -77,7 +77,9 @@ dayjs()
 
 ## Customize
 
-You could create your own locale.
+You could update locale config via plugin [`UpdateLocale`](./Plugin.md#updateLocale)
+
+You could also create your own locale.
 
 Feel free to open a pull request to share your locale.
 

diff --git a/docs/en/Plugin.md b/docs/en/Plugin.md
@@ -442,6 +442,19 @@ dayjs().calendar(null, {
 })
 ```
 
+### UpdateLocale
+
+- UpdateLocale adds `.updateLocale` API to update a locale's properties.
+
+```javascript
+import updateLocale from 'dayjs/plugin/updateLocale'
+dayjs.extend(updateLocale)
+
+dayjs.updateLocale('en', {
+  months : String[]
+})
+```
+
 ## Customize
 
 You could build your own Day.js plugin to meet different needs.

diff --git a/docs/es-es/API-reference.md b/docs/es-es/API-reference.md
@@ -514,3 +514,9 @@ plugin [`MinMax`](./Plugin.md#minmax)
 `.calendar` to display calendar time
 
 plugin [`Calendar`](./Plugin.md#calendar)
+
+### UpdateLocale
+
+`.updateLocale` to update a locale's properties
+
+plugin [`UpdateLocale`](./Plugin.md#updateLocale)
diff --git a/docs/es-es/I18n.md b/docs/es-es/I18n.md
@@ -81,7 +81,9 @@ dayjs()
 
 ## Personalización
 
-You could create your own locale.
+You could update locale config via plugin [`UpdateLocale`](./Plugin.md#updateLocale)
+
+You could also create your own locale.
 
 Feel free to open a pull request to share your locale.
 

diff --git a/docs/es-es/Plugin.md b/docs/es-es/Plugin.md
@@ -438,6 +438,19 @@ dayjs().calendar(null, {
 })
 ```
 
+### UpdateLocale
+
+- UpdateLocale adds `.updateLocale` API to update a locale's properties.
+
+```javascript
+import updateLocale from 'dayjs/plugin/updateLocale'
+dayjs.extend(updateLocale)
+
+dayjs.updateLocale('en', {
+  months : String[]
+})
+```
+
 ## Personalización
 
 Puedes construir tu propio complemento de Day.js para cubrir tus necesidades.

diff --git a/docs/ja/API-reference.md b/docs/ja/API-reference.md
@@ -514,3 +514,9 @@ UTC でパースや表示をしたい場合は、[`UTC`](./Plugin.md#utc)プラ
 `.calendar`で与えた日付のカレンダー上の情報が得られます。
 
 プラグイン [`Calendar`](./Plugin.md#calendar)
+
+### UpdateLocale
+
+`.updateLocale` to update a locale's properties
+
+plugin [`UpdateLocale`](./Plugin.md#updateLocale)
diff --git a/docs/ja/I18n.md b/docs/ja/I18n.md
@@ -77,6 +77,8 @@ dayjs()
 
 ## カスタマイズ
 
+You could update locale config via plugin [`UpdateLocale`](./Plugin.md#updateLocale)
+
 独自のロケールを作成することもできます。
 
 あなたのプラグインを共有する pull request を是非送ってみてください。

diff --git a/docs/ja/Plugin.md b/docs/ja/Plugin.md
@@ -447,6 +447,19 @@ dayjs().calendar(null, {
 })
 ```
 
+### UpdateLocale
+
+- UpdateLocale adds `.updateLocale` API to update a locale's properties.
+
+```javascript
+import updateLocale from 'dayjs/plugin/updateLocale'
+dayjs.extend(updateLocale)
+
+dayjs.updateLocale('en', {
+  months : String[]
+})
+```
+
 ## カスタマイズ
 
 さまざまなニーズに合わせて独自の Day.js プラグインを構築することができます。

diff --git a/docs/ko/API-reference.md b/docs/ko/API-reference.md
@@ -513,3 +513,9 @@ plugin [`MinMax`](./Plugin.md#minmax)
 `.calendar` to display calendar time
 
 plugin [`Calendar`](./Plugin.md#calendar)
+
+### UpdateLocale
+
+`.updateLocale` to update a locale's properties
+
+plugin [`UpdateLocale`](./Plugin.md#updateLocale)
diff --git a/docs/ko/I18n.md b/docs/ko/I18n.md
@@ -77,6 +77,8 @@ dayjs()
 
 ## Customize
 
+You could update locale config via plugin [`UpdateLocale`](./Plugin.md#updateLocale)
+
 당신만의 locale을 만들 수 있습니다.
 
 locale을 공휴하기위해 풀 리퀘스트를 여십시오.

diff --git a/docs/ko/Plugin.md b/docs/ko/Plugin.md
@@ -439,6 +439,19 @@ dayjs().calendar(null, {
 })
 ```
 
+### UpdateLocale
+
+- UpdateLocale adds `.updateLocale` API to update a locale's properties.
+
+```javascript
+import updateLocale from 'dayjs/plugin/updateLocale'
+dayjs.extend(updateLocale)
+
+dayjs.updateLocale('en', {
+  months : String[]
+})
+```
+
 ## Customize
 
 다양한 요구를 충족하기위해 자신만의 Day.js 플러그인을 만들 수 있습니다.

diff --git a/docs/pt-br/API-reference.md b/docs/pt-br/API-reference.md
@@ -512,3 +512,9 @@ plugin [`MinMax`](./Plugin.md#minmax)
 `.calendar` to display calendar time
 
 plugin [`Calendar`](./Plugin.md#calendar)
+
+### UpdateLocale
+
+`.updateLocale` to update a locale's properties
+
+plugin [`UpdateLocale`](./Plugin.md#updateLocale)
diff --git a/docs/pt-br/I18n.md b/docs/pt-br/I18n.md
@@ -77,6 +77,8 @@ dayjs()
 
 ## Customizar
 
+You could update locale config via plugin [`UpdateLocale`](./Plugin.md#updateLocale)
+
 Você pode criar o seu próprio _locale_.
 
 Sinta-se a vontade para abrir uma pull request e compartilhar sua _locale_.

diff --git a/docs/pt-br/Plugin.md b/docs/pt-br/Plugin.md
@@ -438,6 +438,19 @@ dayjs().calendar(null, {
 })
 ```
 
+### UpdateLocale
+
+- UpdateLocale adds `.updateLocale` API to update a locale's properties.
+
+```javascript
+import updateLocale from 'dayjs/plugin/updateLocale'
+dayjs.extend(updateLocale)
+
+dayjs.updateLocale('en', {
+  months : String[]
+})
+```
+
 ## Customizar
 
 Você também pode construir seu próprio plugin Day.js para diferentes necessidades.

diff --git a/docs/zh-cn/API-reference.md b/docs/zh-cn/API-reference.md
@@ -564,3 +564,9 @@ plugin [`MinMax`](./Plugin.md#minmax)
 `.calendar` 来显示日历时间
 
 plugin [`Calendar`](./Plugin.md#calendar)
+
+### 更新语言配置
+
+`.updateLocale` 来更新语言配置的属性
+
+plugin [`UpdateLocale`](./Plugin.md#updateLocale)
diff --git a/docs/zh-cn/I18n.md b/docs/zh-cn/I18n.md
@@ -77,7 +77,9 @@ dayjs()
 
 ## 自定义
 
-你可以根据需要自由的编写一个 Day.js 语言配置
+你可以使用 [`UpdateLocale`](./Plugin.md#updateLocale) 插件来更新语言配置
+
+你还可以根据需要自由的编写一个 Day.js 语言配置
 
 同时欢迎提交 PR 与大家分享你的语言配置
 
@@ -93,6 +95,20 @@ const localeObject = {
   months: 'Enero_Febrero ... '.split('_'), // 月份 Array
   monthsShort: 'Jan_F'.split('_'), // 可选, 短的月份 Array, 如果没提供则使用前三个字符
   ordinal: n => `${n}º`, // 序号生成工厂函数 Function (number) => return number + output
+  formats: {
+    // 时间日期格式 - 长
+    LTS: 'h:mm:ss A',
+    LT: 'h:mm A',
+    L: 'MM/DD/YYYY',
+    LL: 'MMMM D, YYYY',
+    LLL: 'MMMM D, YYYY h:mm A',
+    LLLL: 'dddd, MMMM D, YYYY h:mm A',
+    // 时间日期格式 - 短
+    l: 'D/M/YYYY',
+    ll: 'D MMM, YYYY',
+    lll: 'D MMM, YYYY h:mm A',
+    llll: 'ddd, MMM D, YYYY h:mm A'
+  },
   relativeTime: {
     // 相对时间, %s %d 不用翻译
     future: 'in %s', // e.g. in 2 hours, %s been replaced with 2hours

diff --git a/docs/zh-cn/Plugin.md b/docs/zh-cn/Plugin.md
@@ -441,6 +441,19 @@ dayjs().calendar(null, {
 })
 ```
 
+### UpdateLocale
+
+- UpdateLocale 增加了 `.updateLocale` API 来更新语言配置的属性。
+
+```javascript
+import updateLocale from 'dayjs/plugin/updateLocale'
+dayjs.extend(updateLocale)
+
+dayjs.updateLocale('en', {
+  months : String[]
+})
+```
+
 ## 自定义
 
 你可以根据需要自由的编写一个 Day.js 插件

diff --git a/src/locale/cs.js b/src/locale/cs.js
@@ -1,5 +1,52 @@
 import dayjs from 'dayjs'
 
+function plural(n) {
+  return (n > 1) && (n < 5) && (~~(n / 10) !== 1) // eslint-disable-line
+}
+/* eslint-disable */ 
+function translate(number, withoutSuffix, key, isFuture) {
+  const result = `${number} `
+  switch (key) {
+    case 's': // a few seconds / in a few seconds / a few seconds ago
+      return (withoutSuffix || isFuture) ? 'pár sekund' : 'pár sekundami'
+    case 'm': // a minute / in a minute / a minute ago
+      return withoutSuffix ? 'minuta' : (isFuture ? 'minutu' : 'minutou')
+    case 'mm': // 9 minutes / in 9 minutes / 9 minutes ago
+      if (withoutSuffix || isFuture) {
+        return result + (plural(number) ? 'minuty' : 'minut')
+      }
+      return `${result}minutami`
+    case 'h': // an hour / in an hour / an hour ago
+      return withoutSuffix ? 'hodina' : (isFuture ? 'hodinu' : 'hodinou')
+    case 'hh': // 9 hours / in 9 hours / 9 hours ago
+      if (withoutSuffix || isFuture) {
+        return result + (plural(number) ? 'hodiny' : 'hodin')
+      }
+      return `${result}hodinami`
+    case 'd': // a day / in a day / a day ago
+      return (withoutSuffix || isFuture) ? 'den' : 'dnem'
+    case 'dd': // 9 days / in 9 days / 9 days ago
+      if (withoutSuffix || isFuture) {
+        return result + (plural(number) ? 'dny' : 'dní')
+      }
+      return `${result}dny`
+    case 'M': // a month / in a month / a month ago
+      return (withoutSuffix || isFuture) ? 'měsíc' : 'měsícem'
+    case 'MM': // 9 months / in 9 months / 9 months ago
+      if (withoutSuffix || isFuture) {
+        return result + (plural(number) ? 'měsíce' : 'měsíců')
+      }
+      return `${result}měsíci`
+    case 'y': // a year / in a year / a year ago
+      return (withoutSuffix || isFuture) ? 'rok' : 'rokem'
+    case 'yy': // 9 years / in 9 years / 9 years ago
+      if (withoutSuffix || isFuture) {
+        return result + (plural(number) ? 'roky' : 'let')
+      }
+      return `${result}lety`
+  }
+}
+/* eslint-enable */
 const locale = {
   name: 'cs',
   weekdays: 'neděle_pondělí_úterý_středa_čtvrtek_pátek_sobota'.split('_'),
@@ -21,17 +68,17 @@ const locale = {
   relativeTime: {
     future: 'za %s',
     past: 'před %s',
-    s: 'několik sekund',
-    m: 'minuta',
-    mm: '%d minut',
-    h: 'hodina',
-    hh: '%d hodin',
-    d: 'den',
-    dd: '%d dnů',
-    M: 'měsíc',
-    MM: '%d měsíců',
-    y: 'rok',
-    yy: '%d roků'
+    s: translate,
+    m: translate,
+    mm: translate,
+    h: translate,
+    hh: translate,
+    d: translate,
+    dd: translate,
+    M: translate,
+    MM: translate,
+    y: translate,
+    yy: translate
   }
 }
 

diff --git a/src/locale/ru.js b/src/locale/ru.js
@@ -7,6 +7,26 @@ const monthShortFormat = 'янв._февр._мар._апр._мая_июня_ию
 const monthShortStandalone = 'янв._февр._март_апр._май_июнь_июль_авг._сент._окт._нояб._дек.'.split('_')
 
 const MONTHS_IN_FORMAT = /D[oD]?(\[[^[\]]*\]|\s)+MMMM?/
+
+function plural(word, num) {
+  const forms = word.split('_')
+  return num % 10 === 1 && num % 100 !== 11 ? forms[0] : (num % 10 >= 2 && num % 10 <= 4 && (num % 100 < 10 || num % 100 >= 20) ? forms[1] : forms[2]) // eslint-disable-line
+}
+function relativeTimeWithPlural(number, withoutSuffix, key) {
+  const format = {
+    mm: withoutSuffix ? 'минута_минуты_минут' : 'минуту_минуты_минут',
+    hh: 'час_часа_часов',
+    dd: 'день_дня_дней',
+    MM: 'месяц_месяца_месяцев',
+    yy: 'год_года_лет'
+  }
+  if (key === 'm') {
+    return withoutSuffix ? 'минута' : 'минуту'
+  }
+
+  return `${number} ${plural(format[key], +number)}`
+}
+
 const locale = {
   name: 'ru',
   weekdays: 'воскресенье_понедельник_вторник_среда_четверг_пятница_суббота'.split('_'),
@@ -37,16 +57,16 @@ const locale = {
     future: 'через %s',
     past: '%s назад',
     s: 'несколько секунд',
-    m: 'минута',
-    mm: '%d минут',
+    m: relativeTimeWithPlural,
+    mm: relativeTimeWithPlural,
     h: 'час',
-    hh: '%d часов',
+    hh: relativeTimeWithPlural,
     d: 'день',
-    dd: '%d дней',
+    dd: relativeTimeWithPlural,
     M: 'месяц',
-    MM: '%d месяцев',
+    MM: relativeTimeWithPlural,
     y: 'год',
-    yy: '%d лет'
+    yy: relativeTimeWithPlural
   },
   ordinal: n => n
 }

diff --git a/src/locale/uk.js b/src/locale/uk.js
@@ -1,5 +1,25 @@
 import dayjs from 'dayjs'
 
+function plural(word, num) {
+  const forms = word.split('_')
+  return num % 10 === 1 && num % 100 !== 11 ? forms[0] : (num % 10 >= 2 && num % 10 <= 4 && (num % 100 < 10 || num % 100 >= 20) ? forms[1] : forms[2]) // eslint-disable-line
+}
+function relativeTimeWithPlural(number, withoutSuffix, key) {
+  const format = {
+    ss: withoutSuffix ? 'секунда_секунди_секунд' : 'секунду_секунди_секунд',
+    mm: withoutSuffix ? 'хвилина_хвилини_хвилин' : 'хвилину_хвилини_хвилин',
+    hh: withoutSuffix ? 'година_години_годин' : 'годину_години_годин',
+    dd: 'день_дні_днів',
+    MM: 'місяць_місяці_місяців',
+    yy: 'рік_роки_років'
+  }
+  if (key === 'm') {
+    return withoutSuffix ? 'хвилина' : 'хвилину'
+  }
+
+  return `${number} ${plural(format[key], +number)}`
+}
+
 const locale = {
   name: 'uk',
   weekdays: 'неділя_понеділок_вівторок_середа_четвер_п’ятниця_субота'.split('_'),
@@ -9,19 +29,19 @@ const locale = {
   monthsShort: 'сiч_лют_бер_квiт_трав_черв_лип_серп_вер_жовт_лист_груд'.split('_'),
   weekStart: 1,
   relativeTime: {
-    future: 'через %s',
+    future: 'за %s',
     past: '%s тому',
     s: 'декілька секунд',
-    m: 'хвилина',
-    mm: '%d хвилин',
-    h: 'година',
-    hh: '%d годин',
+    m: relativeTimeWithPlural,
+    mm: relativeTimeWithPlural,
+    h: 'годину',
+    hh: relativeTimeWithPlural,
     d: 'день',
-    dd: '%d днів',
+    dd: relativeTimeWithPlural,
     M: 'місяць',
-    MM: '%d місяців',
+    MM: relativeTimeWithPlural,
     y: 'рік',
-    yy: '%d роки'
+    yy: relativeTimeWithPlural
   },
   ordinal: n => n,
   formats: {

diff --git a/src/plugin/customParseFormat/index.js b/src/plugin/customParseFormat/index.js
@@ -159,9 +159,9 @@ const parseFormattedInput = (input, format, utc) => {
       ) + (zone.offset * 60 * 1000))
     }
     const now = new Date()
+    const d = day || ((!year && !month) ? now.getDate() : 1)
     const y = year || now.getFullYear()
     const M = month > 0 ? month - 1 : now.getMonth()
-    const d = day || now.getDate()
     const h = hours || 0
     const m = minutes || 0
     const s = seconds || 0
@@ -191,6 +191,7 @@ export default (o, C, d) => {
       locale = pl ? d.Ls[pl] : this.$locale()
       this.$d = parseFormattedInput(date, format, utc)
       this.init(cfg)
+      if (pl) this.$L = pl
     } else {
       oldParse.call(this, cfg)
     }

diff --git a/src/plugin/relativeTime/index.js b/src/plugin/relativeTime/index.js
@@ -35,6 +35,7 @@ export default (o, c, d) => {
     const Tl = T.length
     let result
     let out
+    let isFuture
 
     for (let i = 0; i < Tl; i += 1) {
       let t = T[i]
@@ -44,14 +45,20 @@ export default (o, c, d) => {
           : instance.diff(input, t.d, true)
       }
       const abs = Math.round(Math.abs(result))
+      isFuture = result > 0
       if (abs <= t.r || !t.r) {
         if (abs === 1 && i > 0) t = T[i - 1] // 1 minutes -> a minute
-        out = loc[t.l].replace('%d', abs)
+        const format = loc[t.l]
+        if (typeof format === 'string') {
+          out = format.replace('%d', abs)
+        } else {
+          out = format(abs, withoutSuffix, t.l, isFuture)
+        }
         break
       }
     }
     if (withoutSuffix) return out
-    return ((result > 0) ? loc.future : loc.past).replace('%s', out)
+    return (isFuture ? loc.future : loc.past).replace('%s', out)
   }
   proto.to = function (input, withoutSuffix) {
     return fromTo(input, withoutSuffix, this, true)

diff --git a/src/plugin/updateLocale/index.js b/src/plugin/updateLocale/index.js
@@ -0,0 +1,13 @@
+export default (option, Dayjs, dayjs) => {
+  dayjs.updateLocale = function (locale, customConfig) {
+    const localeList = dayjs.Ls
+    const localeConfig = localeList[locale]
+    if (!localeConfig) return
+    const customConfigKeys = customConfig ? Object.keys(customConfig) : []
+    customConfigKeys.forEach((c) => {
+      localeConfig[c] = customConfig[c]
+    })
+    return localeConfig // eslint-disable-line consistent-return
+  }
+}
+
diff --git a/src/plugin/weekOfYear/index.js b/src/plugin/weekOfYear/index.js
@@ -6,25 +6,14 @@ export default (o, c, d) => {
     if (week !== null) {
       return this.add((week - this.week()) * 7, 'day')
     }
-
     const weekStart = this.$locale().weekStart || 0
-
-    // d(this) clone is for badMutable plugin
-    const endOfYear = d(this).endOf(Y)
-    if (
-      weekStart === 0 &&
-      endOfYear.day() !== 6 &&
-      this.month() === 11 &&
-      31 - this.date() <= endOfYear.day()
-    ) {
-      return 1
-    }
-
     const startOfYear = d(this).startOf(Y)
     const compareDay = startOfYear.subtract(startOfYear.day() - weekStart, D).subtract(1, MS)
     const diffInWeek = this.diff(compareDay, W, true)
-    return Math.ceil(diffInWeek)
+    const result = Math.ceil(diffInWeek)
+    return result > 52 ? 1 : result
   }
+
   proto.weeks = function (week = null) {
     return this.week(week)
   }

diff --git a/test/locale/cs.test.js b/test/locale/cs.test.js
@@ -0,0 +1,52 @@
+import moment from 'moment'
+import MockDate from 'mockdate'
+import dayjs from '../../src'
+import relativeTime from '../../src/plugin/relativeTime'
+import '../../src/locale/cs'
+
+dayjs.extend(relativeTime)
+
+beforeEach(() => {
+  MockDate.set(new Date())
+})
+
+afterEach(() => {
+  MockDate.reset()
+})
+
+it('RelativeTime: Time from X', () => {
+  const T = [
+    [44.4, 'second'], // a few seconds
+    [89.5, 'second'], // a minute
+    [2, 'minute'], // 2 minutes
+    [43, 'minute'], // 44 minutes
+    [45, 'minute'], // an hour
+    [3, 'hour'], // 3 hours
+    [21, 'hour'], // 21 hours
+    [1, 'day'], // a day
+    [3, 'day'], // 3 day
+    [25, 'day'], // 25 days
+    [1, 'month'], // a month
+    [2, 'month'], // 2 month
+    [10, 'month'], // 10 month
+    [1, 'year'], // a year
+    [2, 'year'], // 2 year
+    [5, 'year'], // 5 year
+    [18, 'month'] // 2 years
+  ]
+
+  T.forEach((t) => {
+    dayjs.locale('cs')
+    moment.locale('cs')
+    const dayjsDay = dayjs()
+    const momentDay = moment()
+    const dayjsCompare = dayjs().add(t[0], t[1])
+    const momentCompare = moment().add(t[0], t[1])
+    expect(dayjsDay.from(dayjsCompare))
+      .toBe(momentDay.from(momentCompare))
+    expect(dayjsDay.to(dayjsCompare))
+      .toBe(momentDay.to(momentCompare))
+    expect(dayjsDay.from(dayjsCompare, true))
+      .toBe(momentDay.from(momentCompare, true))
+  })
+})
diff --git a/test/locale/ru.test.js b/test/locale/ru.test.js
@@ -1,8 +1,11 @@
 import moment from 'moment'
 import MockDate from 'mockdate'
 import dayjs from '../../src'
+import relativeTime from '../../src/plugin/relativeTime'
 import '../../src/locale/ru'
 
+dayjs.extend(relativeTime)
+
 beforeEach(() => {
   MockDate.set(new Date())
 })
@@ -23,3 +26,24 @@ it('Format Month with locale function', () => {
     expect(dayjsRU.format(testFormat3)).toEqual(momentRU.format(testFormat3))
   }
 })
+
+it('RelativeTime: Time from X', () => {
+  const T = [
+    [44.4, 'second'], // a few seconds
+    [89.5, 'second'], // a minute
+    [43, 'minute'], // 44 minutes
+    [21, 'hour'], // 21 hours
+    [25, 'day'], // 25 days
+    [10, 'month'], // 2 month
+    [18, 'month'] // 2 years
+  ]
+
+  T.forEach((t) => {
+    dayjs.locale('ru')
+    moment.locale('ru')
+    expect(dayjs().from(dayjs().add(t[0], t[1])))
+      .toBe(moment().from(moment().add(t[0], t[1])))
+    expect(dayjs().from(dayjs().add(t[0], t[1]), true))
+      .toBe(moment().from(moment().add(t[0], t[1]), true))
+  })
+})
diff --git a/test/locale/uk.test.js b/test/locale/uk.test.js
@@ -0,0 +1,36 @@
+import moment from 'moment'
+import MockDate from 'mockdate'
+import dayjs from '../../src'
+import relativeTime from '../../src/plugin/relativeTime'
+import '../../src/locale/uk'
+
+dayjs.extend(relativeTime)
+
+beforeEach(() => {
+  MockDate.set(new Date())
+})
+
+afterEach(() => {
+  MockDate.reset()
+})
+
+it('RelativeTime: Time from X', () => {
+  const T = [
+    [44.4, 'second'], // a few seconds
+    [89.5, 'second'], // a minute
+    [43, 'minute'], // 44 minutes
+    [21, 'hour'], // 21 hours
+    [25, 'day'], // 25 days
+    [10, 'month'], // 2 month
+    [18, 'month'] // 2 years
+  ]
+
+  T.forEach((t) => {
+    dayjs.locale('uk')
+    moment.locale('uk')
+    expect(dayjs().from(dayjs().add(t[0], t[1])))
+      .toBe(moment().from(moment().add(t[0], t[1])))
+    expect(dayjs().from(dayjs().add(t[0], t[1]), true))
+      .toBe(moment().from(moment().add(t[0], t[1]), true))
+  })
+})
diff --git a/test/plugin/customParseFormat.test.js b/test/plugin/customParseFormat.test.js
@@ -161,6 +161,10 @@ it('return Invalid Date when parse corrupt short string', () => {
   expect(dayjs(input, format).format()).toBe('Invalid Date')
 })
 
+it('YYYY-MM set 1st day of the month', () => {
+  expect(dayjs('2019-02', 'YYYY-MM').format('YYYY-MM-DD')).toBe('2019-02-01')
+})
+
 it('Invalid Dates', () => {
   expect(dayjs('10/12/2014', 'YYYY-MM-DD').format('MM-DD-YYYY')).toBe('Invalid Date')
   expect(dayjs('10-12-2014', 'YYYY-MM-DD').format('MM-DD-YYYY')).toBe('Invalid Date')
@@ -192,12 +196,20 @@ it('correctly parse ordinal', () => {
   const inputFalse = '7st March 2019'
   const inputZHCN = '7日 三月 2019'
   const format = 'Do MMMM YYYY'
+  const displayFormatWithLocale = 'MMMM dddd'
   expect(dayjs(input, format).valueOf())
     .toBe(moment(input, format).valueOf())
   expect(dayjs(input2, format).valueOf())
     .toBe(moment(input2, format).valueOf())
   expect(dayjs(inputFalse, format).valueOf())
     .toBe(moment(inputFalse, format).valueOf())
-  expect(dayjs(inputZHCN, format, 'zh-cn').valueOf())
-    .toBe(moment(inputZHCN, format, 'zh-cn').valueOf())
+
+  const dayjsCN = dayjs(inputZHCN, format, 'zh-cn')
+  const momentCN = moment(inputZHCN, format, 'zh-cn')
+  expect(dayjsCN.valueOf())
+    .toBe(momentCN.valueOf())
+  expect(dayjsCN.format(displayFormatWithLocale))
+    .toBe(momentCN.format(displayFormatWithLocale))
+  expect(dayjsCN.locale())
+    .toBe(momentCN.locale())
 })
diff --git a/test/plugin/relativeTime.test.js b/test/plugin/relativeTime.test.js
@@ -3,6 +3,7 @@ import moment from 'moment'
 import dayjs from '../../src'
 import relativeTime from '../../src/plugin/relativeTime'
 import utc from '../../src/plugin/utc'
+import '../../src/locale/ru'
 
 dayjs.extend(relativeTime)
 
@@ -50,7 +51,7 @@ it('Time from X', () => {
     [1, 'month'], // a month
     [45, 'day'], // a month
     [47, 'day'], // 2 month
-    [10, 'month'], // 2 month
+    [10, 'month'], // 10 month
     [11, 'month'], // a year
     [1, 'year'], // a year
     [17, 'month'], // a year
@@ -83,6 +84,15 @@ it('Time to X', () => {
   expect(dayjs().to(dayjs().subtract(3, 'year'))).toBe(moment().to(moment().subtract(3, 'year')))
 })
 
+it('Locale Fonction', () => {
+  // e.g. in ru locale, m: x minute require additional processing
+  // and provides as a function instead of a string
+  const str0 = '2020-01-06 15:53:00'
+  const str = '2020-01-06 15:52:15'
+  const result = dayjs(str0).locale('ru').to(str)
+  expect(result).toEqual(expect.any(String))
+})
+
 // https://github.com/iamkun/dayjs/issues/646
 it('Time from now with UTC', () => {
   dayjs.extend(utc)

diff --git a/test/plugin/updateLocale.test.js b/test/plugin/updateLocale.test.js
@@ -0,0 +1,71 @@
+import MockDate from 'mockdate'
+import moment from 'moment'
+import dayjs from '../../src'
+import updateLocale from '../../src/plugin/updateLocale'
+import localizedFormat from '../../src/plugin/localizedFormat'
+import '../../src/locale/zh-cn'
+
+dayjs.extend(updateLocale)
+dayjs.extend(localizedFormat)
+
+beforeEach(() => {
+  MockDate.set(new Date())
+})
+
+afterEach(() => {
+  MockDate.reset()
+})
+
+const newLocale = {
+  months: new Array(12).fill('testMonth'),
+  formats: { // formats for dayjs and longDateFormat for momentjs
+    LT: '[testFormat]'
+  },
+  longDateFormat: {
+    LT: '[testFormat]'
+  }
+}
+
+const formatString = 'MMMM LT'
+
+describe('Update locale', () => {
+  it('Invalid argument', () => {
+    const result = dayjs.updateLocale('InvalidLocaleName', {})
+    expect(result)
+      .toEqual(undefined)
+    expect(dayjs().format(formatString))
+      .toEqual(moment().format(formatString))
+  })
+
+  it('Return value', () => {
+    const result1 = dayjs.updateLocale('en')
+    expect(typeof result1).toEqual('object')
+    const result2 = dayjs.updateLocale('en', {})
+    expect(typeof result2).toEqual('object')
+    const result3 = dayjs.updateLocale('en', newLocale)
+    expect(typeof result3).toEqual('object')
+  })
+
+  it('Update build-in en locale', () => {
+    moment.updateLocale('en', newLocale)
+    dayjs.updateLocale('en', newLocale)
+
+    expect(dayjs().format(formatString))
+      .toEqual('testMonth testFormat')
+
+    expect(dayjs().format(formatString))
+      .toEqual(moment().format(formatString))
+  })
+
+  it('Update imported zh-cn locale', () => {
+    moment.updateLocale('zh-cn', newLocale)
+    dayjs.updateLocale('zh-cn', newLocale)
+    dayjs.locale('zh-cn')
+    moment.locale('zh-cn')
+    expect(dayjs().format(formatString))
+      .toEqual('testMonth testFormat')
+
+    expect(dayjs().format(formatString))
+      .toEqual(moment().format(formatString))
+  })
+})
diff --git a/test/plugin/weekOfYear.test.js b/test/plugin/weekOfYear.test.js
@@ -40,6 +40,7 @@ it('Week of year with locale', () => {
   // Edges
   expect(dayjs('2018-12-30').week()).toBe(moment('2018-12-30').week())
   expect(dayjs('2019-12-29').week()).toBe(moment('2019-12-29').week())
+  expect(dayjs('2019-12-30').week()).toBe(moment('2019-12-30').week())
 })
 
 it('Format w ww wo', () => {

diff --git a/types/plugin/minMax.d.ts b/types/plugin/minMax.d.ts
@@ -1,4 +1,4 @@
-import { PluginFunc, ConfigType } from 'dayjs'
+import { PluginFunc } from 'dayjs'
 
 declare const plugin: PluginFunc
 export = plugin

diff --git a/types/plugin/updateLocale.d.ts b/types/plugin/updateLocale.d.ts
@@ -0,0 +1,8 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
+
+declare module 'dayjs' {
+  export function updateLocale(localeName: String, customConfig: Object): any
+}