feat: Add epoch time as a read-only non-enumerable property to the ti…

…me object

Improve performance of getting the UNIX time for a time object created from the UNIX time earlier.

README.md

@@ -9,7 +9,7 @@
 
 [![NPM Downloads](https://nodei.co/npm/timezone-support.png?downloads=true&stars=true)](https://www.npmjs.com/package/timezone-support)
 
-Low-level time zone listing and date converting. Intended for adding time zone support to high-level date libraries, but also for direct application usage.
+Lightweight time zone listing and date converting. Intended for adding time zone support to high-level date libraries, but also for direct application usage.
 
 * Tiny code base - 3.5 KB minified, 1.5 KB gzipped. Do not pack unnecessary weight in your application.
 * Packed time zone data - 175 KB minified, 22.5 KB gzipped. Single time zones are unpacked on demand.
@@ -251,7 +251,7 @@ In lieu of a formal styleguide, take care to maintain the existing coding style.
 
 ## Release History
 
-* 2018-09-03   v1.0.0   Initial release
+* 2018-09-02   v1.0.0   Initial release
 
 ## License
 

package.json

@@ -1,7 +1,7 @@
 {
   "name": "timezone-support",
   "version": "0.0.0-development",
-  "description": "Low-level time zone listing and date converting. Serves for adding time support to high-level date libraries.",
+  "description": "Lightweight time zone support for your applications or other date libraries.",
   "author": {
     "name": "Ferdinand Prantl",
     "email": "[email protected]",

src/convert/convert.js

@@ -16,6 +16,10 @@ function getTransition (unixTime, timeZone) {
   return { abbreviation, offset }
 }
 
+function attachEpoch (time, unixTime) {
+  Object.defineProperty(time, 'epoch', { value: unixTime })
+}
+
 function setTimeZone (time, timeZone, options) {
   if (time instanceof Date) {
     const { useUTC } = options || {}
@@ -28,12 +32,15 @@ function setTimeZone (time, timeZone, options) {
       throw new Error('Source of the date parts missing.')
     }
     time = extract(time)
+  } else {
+    const { year, month, day, hours, minutes, seconds = 0, milliseconds = 0 } = time
+    time = { year, month, day, hours, minutes, seconds, milliseconds }
   }
   const unixTime = getUnixTimeFromUTC(time)
   const { abbreviation, offset } = getTransition(unixTime, timeZone)
-  const zone = { abbreviation, offset }
-  const { year, month, day, hours, minutes, seconds = 0, milliseconds = 0 } = time
-  return { year, month, day, hours, minutes, seconds, milliseconds, zone }
+  time.zone = { abbreviation, offset }
+  attachEpoch(time, unixTime)
+  return time
 }
 
 function getZonedTime (date, timeZone) {
@@ -45,12 +52,19 @@ function getZonedTime (date, timeZone) {
   }
   const time = getUTCTime(date)
   time.zone = { abbreviation, offset }
+  attachEpoch(time, unixTime)
   return time
 }
 
 function getUnixTime (time, timeZone) {
+  let { zone, epoch } = time
+  if (epoch) {
+    if (timeZone) {
+      throw new Error('Both epoch and other time zone specified.')
+    }
+    return epoch
+  }
   const unixTime = getUnixTimeFromUTC(time)
-  let { zone } = time
   if (zone) {
     if (timeZone) {
       throw new Error('Two time zones specified.')

src/convert/utc-date.js

@@ -20,8 +20,8 @@ function getLocalTime (date) {
   const day = date.getDate()
   const hours = date.getHours()
   const minutes = date.getMinutes()
-  const seconds = date.getSeconds()
-  const milliseconds = date.getMilliseconds()
+  const seconds = date.getSeconds() || 0
+  const milliseconds = date.getMilliseconds() || 0
   return { year, month, day, hours, minutes, seconds, milliseconds }
 }
 

test/formatZonedTime.test.js

@@ -7,7 +7,7 @@ it('is exported as a function', () => {
 })
 
 it('formats a time object to a string with no padding needed', () => {
-  const honoluluDate = {
+  const honoluluTime = {
     year: 2017,
     month: 11,
     day: 15,
@@ -20,12 +20,12 @@ it('formats a time object to a string with no padding needed', () => {
       offset: 600
     }
   }
-  const string = formatZonedTime(honoluluDate, 'A S SS SSS s ss m mm h hh H HH D DD M MM Y YY YYYY z Z ZZ')
+  const string = formatZonedTime(honoluluTime, 'A S SS SSS s ss m mm h hh H HH D DD M MM Y YY YYYY z Z ZZ')
   expect(string).toEqual('PM 2 23 234 18 18 17 17 11 11 23 23 15 15 11 11 2017 17 2017 HST -10:00 -1000')
 })
 
 it('pads single digits with zeros', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 1,
     month: 1,
     day: 2,
@@ -38,24 +38,24 @@ it('pads single digits with zeros', () => {
       offset: -60
     }
   }
-  const string = formatZonedTime(berlinDate, 'A S SS SSS s ss m mm h hh H HH D DD M MM Y YY YYYY z Z ZZ')
+  const string = formatZonedTime(berlinTime, 'A S SS SSS s ss m mm h hh H HH D DD M MM Y YY YYYY z Z ZZ')
   expect(string).toEqual('AM 0 00 004 5 05 3 03 9 09 9 09 2 02 1 01 1 01 0001 CET +01:00 +0100')
 })
 
 it('pads pairs of digits with zeros', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 67,
     milliseconds: 34
   }
-  const string = formatZonedTime(berlinDate, 'YYYY SSS')
+  const string = formatZonedTime(berlinTime, 'YYYY SSS')
   expect(string).toEqual('0067 034')
 })
 
 it('pads triplets of digits with zeros', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 967
   }
-  const string = formatZonedTime(berlinDate, 'YYYY')
+  const string = formatZonedTime(berlinTime, 'YYYY')
   expect(string).toEqual('0967')
 })
 

test/getUnixTime.test.js

@@ -13,7 +13,7 @@ it('is exported as a function', () => {
 })
 
 it('converts the time object to the correct UNIX time', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 2018,
     month: 1,
     day: 2,
@@ -26,14 +26,14 @@ it('converts the time object to the correct UNIX time', () => {
       offset: -60
     }
   }
-  const unixTime = getUnixTime(berlinDate)
+  const unixTime = getUnixTime(berlinTime)
   expect(typeof unixTime === 'number').toBeTruthy()
-  const utcDate = new Date(Date.UTC(2018, 0, 2, 9, 30, 15, 234))
-  expect(unixTime).toEqual(utcDate.valueOf())
+  const epoch = Date.UTC(2018, 0, 2, 9, 30, 15, 234)
+  expect(unixTime).toEqual(epoch)
 })
 
 it('accepts an explicit time zone as a parameter', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 2018,
     month: 1,
     day: 2,
@@ -42,14 +42,14 @@ it('accepts an explicit time zone as a parameter', () => {
     seconds: 15,
     milliseconds: 234
   }
-  const unixTime = getUnixTime(berlinDate, berlin)
+  const unixTime = getUnixTime(berlinTime, berlin)
   expect(typeof unixTime === 'number').toBeTruthy()
-  const utcDate = new Date(Date.UTC(2018, 0, 2, 9, 30, 15, 234))
-  expect(unixTime).toEqual(utcDate.valueOf())
+  const epoch = Date.UTC(2018, 0, 2, 9, 30, 15, 234)
+  expect(unixTime).toEqual(epoch)
 })
 
 it('seconds and milliseconds are optional in the time object', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 2018,
     month: 1,
     day: 2,
@@ -60,14 +60,14 @@ it('seconds and milliseconds are optional in the time object', () => {
       offset: -60
     }
   }
-  const unixTime = getUnixTime(berlinDate)
+  const unixTime = getUnixTime(berlinTime)
   expect(typeof unixTime === 'number').toBeTruthy()
-  const utcDate = new Date(Date.UTC(2018, 0, 2, 9, 30))
-  expect(unixTime).toEqual(utcDate.valueOf())
+  const epoch = Date.UTC(2018, 0, 2, 9, 30)
+  expect(unixTime).toEqual(epoch)
 })
 
 it('recognizes daylight-saving time', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 2018,
     month: 7,
     day: 2,
@@ -78,14 +78,14 @@ it('recognizes daylight-saving time', () => {
       offset: -120
     }
   }
-  const unixTime = getUnixTime(berlinDate)
+  const unixTime = getUnixTime(berlinTime)
   expect(typeof unixTime === 'number').toBeTruthy()
-  const utcDate = new Date(Date.UTC(2018, 6, 2, 9, 30))
-  expect(unixTime).toEqual(utcDate.valueOf())
+  const epoch = Date.UTC(2018, 6, 2, 9, 30)
+  expect(unixTime).toEqual(epoch)
 })
 
 it('checks, that only one time zone is requested to convert from', () => {
-  const berlinDate = {
+  const berlinTime = {
     year: 2018,
     month: 7,
     day: 2,
@@ -96,5 +96,36 @@ it('checks, that only one time zone is requested to convert from', () => {
       offset: -120
     }
   }
-  expect(() => getUnixTime(berlinDate, berlin)).toThrow()
+  expect(() => getUnixTime(berlinTime, berlin)).toThrow()
+})
+
+it('returns the epoch, that only one time zone is requested to convert from', () => {
+  const berlinTime = {
+    year: 2018,
+    month: 7,
+    day: 2,
+    hours: 11,
+    minutes: 30,
+    epoch: 1530523800000,
+    zone: {
+      abbreviation: 'CEST',
+      offset: -120
+    }
+  }
+  const unixTime = getUnixTime(berlinTime)
+  expect(typeof unixTime === 'number').toBeTruthy()
+  const epoch = Date.UTC(2018, 6, 2, 9, 30)
+  expect(unixTime).toEqual(epoch)
+})
+
+it('checks, that other time zone is not requested if epoch is included', () => {
+  const berlinTime = {
+    year: 2018,
+    month: 7,
+    day: 2,
+    hours: 11,
+    minutes: 30,
+    epoch: 1530523800000
+  }
+  expect(() => getUnixTime(berlinTime, berlin)).toThrow()
 })

test/getZonedTime.test.js

@@ -13,10 +13,10 @@ it('is exported as a function', () => {
 })
 
 it('converts the UNIX time to the correct time object', () => {
-  const utcDate = new Date(Date.UTC(2018, 0, 2, 9, 30, 15, 234))
-  const berlinDate = getZonedTime(utcDate.valueOf(), berlin)
-  expect(typeof berlinDate === 'object').toBeTruthy()
-  const { year, month, day, hours, minutes, seconds, milliseconds, zone } = berlinDate
+  const unixTime = Date.UTC(2018, 0, 2, 9, 30, 15, 234)
+  const berlinTime = getZonedTime(unixTime, berlin)
+  expect(typeof berlinTime === 'object').toBeTruthy()
+  const { year, month, day, hours, minutes, seconds, milliseconds, zone, epoch } = berlinTime
   expect(year).toEqual(2018)
   expect(month).toEqual(1)
   expect(day).toEqual(2)
@@ -27,13 +27,14 @@ it('converts the UNIX time to the correct time object', () => {
   expect(typeof zone === 'object').toBeTruthy()
   expect(zone.abbreviation).toEqual('CET')
   expect(zone.offset).toEqual(-60)
+  expect(epoch).toEqual(1514885415234)
 })
 
 it('recognizes daylight-saving time', () => {
-  const utcDate = new Date(Date.UTC(2018, 6, 2, 9, 30, 15, 234))
-  const berlinDate = getZonedTime(utcDate.valueOf(), berlin)
-  expect(typeof berlinDate === 'object').toBeTruthy()
-  const { year, month, day, hours, minutes, seconds, milliseconds, zone } = berlinDate
+  const unixTime = Date.UTC(2018, 6, 2, 9, 30, 15, 234)
+  const berlinTime = getZonedTime(unixTime.valueOf(), berlin)
+  expect(typeof berlinTime === 'object').toBeTruthy()
+  const { year, month, day, hours, minutes, seconds, milliseconds, zone, epoch } = berlinTime
   expect(year).toEqual(2018)
   expect(month).toEqual(7)
   expect(day).toEqual(2)
@@ -44,13 +45,14 @@ it('recognizes daylight-saving time', () => {
   expect(typeof zone === 'object').toBeTruthy()
   expect(zone.abbreviation).toEqual('CEST')
   expect(zone.offset).toEqual(-120)
+  expect(epoch).toEqual(1530523815234)
 })
 
 it('accepts a Date object instead of a numeric UNIX time', () => {
   const utcDate = new Date(Date.UTC(2018, 6, 2, 9, 30, 15, 234))
-  const berlinDate = getZonedTime(utcDate, berlin)
-  expect(typeof berlinDate === 'object').toBeTruthy()
-  const { year, month, day, hours, minutes, seconds, milliseconds, zone } = berlinDate
+  const berlinTime = getZonedTime(utcDate, berlin)
+  expect(typeof berlinTime === 'object').toBeTruthy()
+  const { year, month, day, hours, minutes, seconds, milliseconds, zone, epoch } = berlinTime
   expect(year).toEqual(2018)
   expect(month).toEqual(7)
   expect(day).toEqual(2)
@@ -61,14 +63,15 @@ it('accepts a Date object instead of a numeric UNIX time', () => {
   expect(typeof zone === 'object').toBeTruthy()
   expect(zone.abbreviation).toEqual('CEST')
   expect(zone.offset).toEqual(-120)
+  expect(epoch).toEqual(1530523815234)
 })
 
 it('optimizes conversion to UTC', () => {
   const utc = findTimeZone('Etc/UTC')
   const utcDate = new Date(Date.UTC(2018, 6, 2, 9, 30, 15, 234))
-  const berlinDate = getZonedTime(utcDate, utc)
-  expect(typeof berlinDate === 'object').toBeTruthy()
-  const { year, month, day, hours, minutes, seconds, milliseconds, zone } = berlinDate
+  const berlinTime = getZonedTime(utcDate, utc)
+  expect(typeof berlinTime === 'object').toBeTruthy()
+  const { year, month, day, hours, minutes, seconds, milliseconds, zone, epoch } = berlinTime
   expect(year).toEqual(2018)
   expect(month).toEqual(7)
   expect(day).toEqual(2)
@@ -79,4 +82,5 @@ it('optimizes conversion to UTC', () => {
   expect(typeof zone === 'object').toBeTruthy()
   expect(zone.abbreviation).toEqual('UTC')
   expect(zone.offset).toEqual(0)
+  expect(epoch).toEqual(1530523815234)
 })

test/setTimeZone.test.js

@@ -4,7 +4,8 @@ const { findTimeZone, setTimeZone } = require('../dist/index')
 
 let berlin
 
-function checkTime ({ year, month, day, hours, minutes, seconds, milliseconds, zone }, checkSeconds) {
+function checkTime (time, checkSeconds) {
+  const { year, month, day, hours, minutes, seconds, milliseconds, zone, epoch } = time
   expect(year).toEqual(2018)
   expect(month).toEqual(1)
   expect(day).toEqual(2)
@@ -13,9 +14,11 @@ function checkTime ({ year, month, day, hours, minutes, seconds, milliseconds, z
   if (checkSeconds) {
     expect(seconds).toEqual(40)
     expect(milliseconds).toEqual(50)
+    expect(epoch).toEqual(1514889040050)
   } else {
     expect(seconds).toEqual(0)
     expect(milliseconds).toEqual(0)
+    expect(epoch).toEqual(1514889000000)
   }
   expect(typeof zone === 'object').toBeTruthy()
   expect(zone.abbreviation).toEqual('CET')
@@ -34,26 +37,26 @@ it('sets the right time zone to the time object', () => {
   const zonelessTime = {
     year: 2018, month: 1, day: 2, hours: 10, minutes: 30, seconds: 40, milliseconds: 50
   }
-  const berlinTIme = setTimeZone(zonelessTime, berlin)
-  checkTime(berlinTIme, true)
+  const berlinTime = setTimeZone(zonelessTime, berlin)
+  checkTime(berlinTime, true)
 })
 
 it('supplies zero seconds and milliseconds, if not present in the input', () => {
   const zonelessTime = { year: 2018, month: 1, day: 2, hours: 10, minutes: 30 }
-  const berlinTIme = setTimeZone(zonelessTime, berlin)
-  checkTime(berlinTIme, false)
+  const berlinTime = setTimeZone(zonelessTime, berlin)
+  checkTime(berlinTime, false)
 })
 
 it('extracts the time from date parts in the UTC representation', () => {
   const zonelessDate = new Date(Date.UTC(2018, 0, 2, 10, 30))
-  const berlinTIme = setTimeZone(zonelessDate, berlin, { useUTC: true })
-  checkTime(berlinTIme, false)
+  const berlinTime = setTimeZone(zonelessDate, berlin, { useUTC: true })
+  checkTime(berlinTime, false)
 })
 
 it('extracts the time from date parts in the local time zone representation', () => {
   const zonelessDate = new Date(2018, 0, 2, 10, 30)
-  const berlinTIme = setTimeZone(zonelessDate, berlin, { useUTC: false })
-  checkTime(berlinTIme, false)
+  const berlinTime = setTimeZone(zonelessDate, berlin, { useUTC: false })
+  checkTime(berlinTime, false)
 })
 
 it('requests the source of date parts, if a date object uis supplied', () => {