materialui-daterange-picker/dist/index.js

A react date range picker implementation using @material-ui.

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/*!
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var MILLISECONDS_IN_MINUTE = 60000;

/**
 * Google Chrome as of 67.0.3396.87 introduced timezones with offset that includes seconds.
 * They usually appear for dates that denote time before the timezones were introduced
 * (e.g. for 'Europe/Prague' timezone the offset is GMT+00:57:44 before 1 October 1891
 * and GMT+01:00:00 after that date)
 *
 * Date#getTimezoneOffset returns the offset in minutes and would return 57 for the example above,
 * which would lead to incorrect calculations.
 *
 * This function returns the timezone offset in milliseconds that takes seconds in account.
 */
var getTimezoneOffsetInMilliseconds = function getTimezoneOffsetInMilliseconds (dirtyDate) {
  var date = new Date(dirtyDate.getTime());
  var baseTimezoneOffset = date.getTimezoneOffset();
  date.setSeconds(0, 0);
  var millisecondsPartOfTimezoneOffset = date.getTime() % MILLISECONDS_IN_MINUTE;

  return baseTimezoneOffset * MILLISECONDS_IN_MINUTE + millisecondsPartOfTimezoneOffset
};

/**
 * @category Common Helpers
 * @summary Is the given argument an instance of Date?
 *
 * @description
 * Is the given argument an instance of Date?
 *
 * @param {*} argument - the argument to check
 * @returns {Boolean} the given argument is an instance of Date
 *
 * @example
 * // Is 'mayonnaise' a Date?
 * var result = isDate('mayonnaise')
 * //=> false
 */
function isDate (argument) {
  return argument instanceof Date
}

var is_date = isDate;

var MILLISECONDS_IN_HOUR = 3600000;
var MILLISECONDS_IN_MINUTE$1 = 60000;
var DEFAULT_ADDITIONAL_DIGITS = 2;

var parseTokenDateTimeDelimeter = /[T ]/;
var parseTokenPlainTime = /:/;

// year tokens
var parseTokenYY = /^(\d{2})$/;
var parseTokensYYY = [
  /^([+-]\d{2})$/, // 0 additional digits
  /^([+-]\d{3})$/, // 1 additional digit
  /^([+-]\d{4})$/ // 2 additional digits
];

var parseTokenYYYY = /^(\d{4})/;
var parseTokensYYYYY = [
  /^([+-]\d{4})/, // 0 additional digits
  /^([+-]\d{5})/, // 1 additional digit
  /^([+-]\d{6})/ // 2 additional digits
];

// date tokens
var parseTokenMM = /^-(\d{2})$/;
var parseTokenDDD = /^-?(\d{3})$/;
var parseTokenMMDD = /^-?(\d{2})-?(\d{2})$/;
var parseTokenWww = /^-?W(\d{2})$/;
var parseTokenWwwD = /^-?W(\d{2})-?(\d{1})$/;

// time tokens
var parseTokenHH = /^(\d{2}([.,]\d*)?)$/;
var parseTokenHHMM = /^(\d{2}):?(\d{2}([.,]\d*)?)$/;
var parseTokenHHMMSS = /^(\d{2}):?(\d{2}):?(\d{2}([.,]\d*)?)$/;

// timezone tokens
var parseTokenTimezone = /([Z+-].*)$/;
var parseTokenTimezoneZ = /^(Z)$/;
var parseTokenTimezoneHH = /^([+-])(\d{2})$/;
var parseTokenTimezoneHHMM = /^([+-])(\d{2}):?(\d{2})$/;

/**
 * @category Common Helpers
 * @summary Convert the given argument to an instance of Date.
 *
 * @description
 * Convert the given argument to an instance of Date.
 *
 * If the argument is an instance of Date, the function returns its clone.
 *
 * If the argument is a number, it is treated as a timestamp.
 *
 * If an argument is a string, the function tries to parse it.
 * Function accepts complete ISO 8601 formats as well as partial implementations.
 * ISO 8601: http://en.wikipedia.org/wiki/ISO_8601
 *
 * If all above fails, the function passes the given argument to Date constructor.
 *
 * @param {Date|String|Number} argument - the value to convert
 * @param {Object} [options] - the object with options
 * @param {0 | 1 | 2} [options.additionalDigits=2] - the additional number of digits in the extended year format
 * @returns {Date} the parsed date in the local time zone
 *
 * @example
 * // Convert string '2014-02-11T11:30:30' to date:
 * var result = parse('2014-02-11T11:30:30')
 * //=> Tue Feb 11 2014 11:30:30
 *
 * @example
 * // Parse string '+02014101',
 * // if the additional number of digits in the extended year format is 1:
 * var result = parse('+02014101', {additionalDigits: 1})
 * //=> Fri Apr 11 2014 00:00:00
 */
function parse (argument, dirtyOptions) {
  if (is_date(argument)) {
    // Prevent the date to lose the milliseconds when passed to new Date() in IE10
    return new Date(argument.getTime())
  } else if (typeof argument !== 'string') {
    return new Date(argument)
  }

  var options = dirtyOptions || {};
  var additionalDigits = options.additionalDigits;
  if (additionalDigits == null) {
    additionalDigits = DEFAULT_ADDITIONAL_DIGITS;
  } else {
    additionalDigits = Number(additionalDigits);
  }

  var dateStrings = splitDateString(argument);

  var parseYearResult = parseYear(dateStrings.date, additionalDigits);
  var year = parseYearResult.year;
  var restDateString = parseYearResult.restDateString;

  var date = parseDate(restDateString, year);

  if (date) {
    var timestamp = date.getTime();
    var time = 0;
    var offset;

    if (dateStrings.time) {
      time = parseTime(dateStrings.time);
    }

    if (dateStrings.timezone) {
      offset = parseTimezone(dateStrings.timezone) * MILLISECONDS_IN_MINUTE$1;
    } else {
      var fullTime = timestamp + time;
      var fullTimeDate = new Date(fullTime);

      offset = getTimezoneOffsetInMilliseconds(fullTimeDate);

      // Adjust time when it's coming from DST
      var fullTimeDateNextDay = new Date(fullTime);
      fullTimeDateNextDay.setDate(fullTimeDate.getDate() + 1);
      var offsetDiff =
        getTimezoneOffsetInMilliseconds(fullTimeDateNextDay) -
        getTimezoneOffsetInMilliseconds(fullTimeDate);
      if (offsetDiff > 0) {
        offset += offsetDiff;
      }
    }

    return new Date(timestamp + time + offset)
  } else {
    return new Date(argument)
  }
}

function splitDateString (dateString) {
  var dateStrings = {};
  var array = dateString.split(parseTokenDateTimeDelimeter);
  var timeString;

  if (parseTokenPlainTime.test(array[0])) {
    dateStrings.date = null;
    timeString = array[0];
  } else {
    dateStrings.date = array[0];
    timeString = array[1];
  }

  if (timeString) {
    var token = parseTokenTimezone.exec(timeString);
    if (token) {
      dateStrings.time = timeString.replace(token[1], '');
      dateStrings.timezone = token[1];
    } else {
      dateStrings.time = timeString;
    }
  }

  return dateStrings
}

function parseYear (dateString, additionalDigits) {
  var parseTokenYYY = parseTokensYYY[additionalDigits];
  var parseTokenYYYYY = parseTokensYYYYY[additionalDigits];

  var token;

  // YYYY or ±YYYYY
  token = parseTokenYYYY.exec(dateString) || parseTokenYYYYY.exec(dateString);
  if (token) {
    var yearString = token[1];
    return {
      year: parseInt(yearString, 10),
      restDateString: dateString.slice(yearString.length)
    }
  }

  // YY or ±YYY
  token = parseTokenYY.exec(dateString) || parseTokenYYY.exec(dateString);
  if (token) {
    var centuryString = token[1];
    return {
      year: parseInt(centuryString, 10) * 100,
      restDateString: dateString.slice(centuryString.length)
    }
  }

  // Invalid ISO-formatted year
  return {
    year: null
  }
}

function parseDate (dateString, year) {
  // Invalid ISO-formatted year
  if (year === null) {
    return null
  }

  var token;
  var date;
  var month;
  var week;

  // YYYY
  if (dateString.length === 0) {
    date = new Date(0);
    date.setUTCFullYear(year);
    return date
  }

  // YYYY-MM
  token = parseTokenMM.exec(dateString);
  if (token) {
    date = new Date(0);
    month = parseInt(token[1], 10) - 1;
    date.setUTCFullYear(year, month);
    return date
  }

  // YYYY-DDD or YYYYDDD
  token = parseTokenDDD.exec(dateString);
  if (token) {
    date = new Date(0);
    var dayOfYear = parseInt(token[1], 10);
    date.setUTCFullYear(year, 0, dayOfYear);
    return date
  }

  // YYYY-MM-DD or YYYYMMDD
  token = parseTokenMMDD.exec(dateString);
  if (token) {
    date = new Date(0);
    month = parseInt(token[1], 10) - 1;
    var day = parseInt(token[2], 10);
    date.setUTCFullYear(year, month, day);
    return date
  }

  // YYYY-Www or YYYYWww
  token = parseTokenWww.exec(dateString);
  if (token) {
    week = parseInt(token[1], 10) - 1;
    return dayOfISOYear(year, week)
  }

  // YYYY-Www-D or YYYYWwwD
  token = parseTokenWwwD.exec(dateString);
  if (token) {
    week = parseInt(token[1], 10) - 1;
    var dayOfWeek = parseInt(token[2], 10) - 1;
    return dayOfISOYear(year, week, dayOfWeek)
  }

  // Invalid ISO-formatted date
  return null
}

function parseTime (timeString) {
  var token;
  var hours;
  var minutes;

  // hh
  token = parseTokenHH.exec(timeString);
  if (token) {
    hours = parseFloat(token[1].replace(',', '.'));
    return (hours % 24) * MILLISECONDS_IN_HOUR
  }

  // hh:mm or hhmm
  token = parseTokenHHMM.exec(timeString);
  if (token) {
    hours = parseInt(token[1], 10);
    minutes = parseFloat(token[2].replace(',', '.'));
    return (hours % 24) * MILLISECONDS_IN_HOUR +
      minutes * MILLISECONDS_IN_MINUTE$1
  }

  // hh:mm:ss or hhmmss
  token = parseTokenHHMMSS.exec(timeString);
  if (token) {
    hours = parseInt(token[1], 10);
    minutes = parseInt(token[2], 10);
    var seconds = parseFloat(token[3].replace(',', '.'));
    return (hours % 24) * MILLISECONDS_IN_HOUR +
      minutes * MILLISECONDS_IN_MINUTE$1 +
      seconds * 1000
  }

  // Invalid ISO-formatted time
  return null
}

function parseTimezone (timezoneString) {
  var token;
  var absoluteOffset;

  // Z
  token = parseTokenTimezoneZ.exec(timezoneString);
  if (token) {
    return 0
  }

  // ±hh
  token = parseTokenTimezoneHH.exec(timezoneString);
  if (token) {
    absoluteOffset = parseInt(token[2], 10) * 60;
    return (token[1] === '+') ? -absoluteOffset : absoluteOffset
  }

  // ±hh:mm or ±hhmm
  token = parseTokenTimezoneHHMM.exec(timezoneString);
  if (token) {
    absoluteOffset = parseInt(token[2], 10) * 60 + parseInt(token[3], 10);
    return (token[1] === '+') ? -absoluteOffset : absoluteOffset
  }

  return 0
}

function dayOfISOYear (isoYear, week, day) {
  week = week || 0;
  day = day || 0;
  var date = new Date(0);
  date.setUTCFullYear(isoYear, 0, 4);
  var fourthOfJanuaryDay = date.getUTCDay() || 7;
  var diff = week * 7 + day + 1 - fourthOfJanuaryDay;
  date.setUTCDate(date.getUTCDate() + diff);
  return date
}

var parse_1 = parse;

/**
 * @category Day Helpers
 * @summary Add the specified number of days to the given date.
 *
 * @description
 * Add the specified number of days to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of days to be added
 * @returns {Date} the new date with the days added
 *
 * @example
 * // Add 10 days to 1 September 2014:
 * var result = addDays(new Date(2014, 8, 1), 10)
 * //=> Thu Sep 11 2014 00:00:00
 */
function addDays (dirtyDate, dirtyAmount) {
  var date = parse_1(dirtyDate);
  var amount = Number(dirtyAmount);
  date.setDate(date.getDate() + amount);
  return date
}

var add_days = addDays;

/**
 * @category Millisecond Helpers
 * @summary Add the specified number of milliseconds to the given date.
 *
 * @description
 * Add the specified number of milliseconds to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of milliseconds to be added
 * @returns {Date} the new date with the milliseconds added
 *
 * @example
 * // Add 750 milliseconds to 10 July 2014 12:45:30.000:
 * var result = addMilliseconds(new Date(2014, 6, 10, 12, 45, 30, 0), 750)
 * //=> Thu Jul 10 2014 12:45:30.750
 */
function addMilliseconds (dirtyDate, dirtyAmount) {
  var timestamp = parse_1(dirtyDate).getTime();
  var amount = Number(dirtyAmount);
  return new Date(timestamp + amount)
}

var add_milliseconds = addMilliseconds;

var MILLISECONDS_IN_HOUR$1 = 3600000;

/**
 * @category Hour Helpers
 * @summary Add the specified number of hours to the given date.
 *
 * @description
 * Add the specified number of hours to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of hours to be added
 * @returns {Date} the new date with the hours added
 *
 * @example
 * // Add 2 hours to 10 July 2014 23:00:00:
 * var result = addHours(new Date(2014, 6, 10, 23, 0), 2)
 * //=> Fri Jul 11 2014 01:00:00
 */
function addHours (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  return add_milliseconds(dirtyDate, amount * MILLISECONDS_IN_HOUR$1)
}

var add_hours = addHours;

/**
 * @category Week Helpers
 * @summary Return the start of a week for the given date.
 *
 * @description
 * Return the start of a week for the given date.
 * The result will be in the local timezone.
 *
 * @param {Date|String|Number} date - the original date
 * @param {Object} [options] - the object with options
 * @param {Number} [options.weekStartsOn=0] - the index of the first day of the week (0 - Sunday)
 * @returns {Date} the start of a week
 *
 * @example
 * // The start of a week for 2 September 2014 11:55:00:
 * var result = startOfWeek(new Date(2014, 8, 2, 11, 55, 0))
 * //=> Sun Aug 31 2014 00:00:00
 *
 * @example
 * // If the week starts on Monday, the start of the week for 2 September 2014 11:55:00:
 * var result = startOfWeek(new Date(2014, 8, 2, 11, 55, 0), {weekStartsOn: 1})
 * //=> Mon Sep 01 2014 00:00:00
 */
function startOfWeek (dirtyDate, dirtyOptions) {
  var weekStartsOn = dirtyOptions ? (Number(dirtyOptions.weekStartsOn) || 0) : 0;

  var date = parse_1(dirtyDate);
  var day = date.getDay();
  var diff = (day < weekStartsOn ? 7 : 0) + day - weekStartsOn;

  date.setDate(date.getDate() - diff);
  date.setHours(0, 0, 0, 0);
  return date
}

var start_of_week = startOfWeek;

/**
 * @category ISO Week Helpers
 * @summary Return the start of an ISO week for the given date.
 *
 * @description
 * Return the start of an ISO week for the given date.
 * The result will be in the local timezone.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} date - the original date
 * @returns {Date} the start of an ISO week
 *
 * @example
 * // The start of an ISO week for 2 September 2014 11:55:00:
 * var result = startOfISOWeek(new Date(2014, 8, 2, 11, 55, 0))
 * //=> Mon Sep 01 2014 00:00:00
 */
function startOfISOWeek (dirtyDate) {
  return start_of_week(dirtyDate, {weekStartsOn: 1})
}

var start_of_iso_week = startOfISOWeek;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Get the ISO week-numbering year of the given date.
 *
 * @description
 * Get the ISO week-numbering year of the given date,
 * which always starts 3 days before the year's first Thursday.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} date - the given date
 * @returns {Number} the ISO week-numbering year
 *
 * @example
 * // Which ISO-week numbering year is 2 January 2005?
 * var result = getISOYear(new Date(2005, 0, 2))
 * //=> 2004
 */
function getISOYear (dirtyDate) {
  var date = parse_1(dirtyDate);
  var year = date.getFullYear();

  var fourthOfJanuaryOfNextYear = new Date(0);
  fourthOfJanuaryOfNextYear.setFullYear(year + 1, 0, 4);
  fourthOfJanuaryOfNextYear.setHours(0, 0, 0, 0);
  var startOfNextYear = start_of_iso_week(fourthOfJanuaryOfNextYear);

  var fourthOfJanuaryOfThisYear = new Date(0);
  fourthOfJanuaryOfThisYear.setFullYear(year, 0, 4);
  fourthOfJanuaryOfThisYear.setHours(0, 0, 0, 0);
  var startOfThisYear = start_of_iso_week(fourthOfJanuaryOfThisYear);

  if (date.getTime() >= startOfNextYear.getTime()) {
    return year + 1
  } else if (date.getTime() >= startOfThisYear.getTime()) {
    return year
  } else {
    return year - 1
  }
}

var get_iso_year = getISOYear;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Return the start of an ISO week-numbering year for the given date.
 *
 * @description
 * Return the start of an ISO week-numbering year,
 * which always starts 3 days before the year's first Thursday.
 * The result will be in the local timezone.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} date - the original date
 * @returns {Date} the start of an ISO year
 *
 * @example
 * // The start of an ISO week-numbering year for 2 July 2005:
 * var result = startOfISOYear(new Date(2005, 6, 2))
 * //=> Mon Jan 03 2005 00:00:00
 */
function startOfISOYear (dirtyDate) {
  var year = get_iso_year(dirtyDate);
  var fourthOfJanuary = new Date(0);
  fourthOfJanuary.setFullYear(year, 0, 4);
  fourthOfJanuary.setHours(0, 0, 0, 0);
  var date = start_of_iso_week(fourthOfJanuary);
  return date
}

var start_of_iso_year = startOfISOYear;

/**
 * @category Day Helpers
 * @summary Return the start of a day for the given date.
 *
 * @description
 * Return the start of a day for the given date.
 * The result will be in the local timezone.
 *
 * @param {Date|String|Number} date - the original date
 * @returns {Date} the start of a day
 *
 * @example
 * // The start of a day for 2 September 2014 11:55:00:
 * var result = startOfDay(new Date(2014, 8, 2, 11, 55, 0))
 * //=> Tue Sep 02 2014 00:00:00
 */
function startOfDay (dirtyDate) {
  var date = parse_1(dirtyDate);
  date.setHours(0, 0, 0, 0);
  return date
}

var start_of_day = startOfDay;

var MILLISECONDS_IN_MINUTE$2 = 60000;
var MILLISECONDS_IN_DAY = 86400000;

/**
 * @category Day Helpers
 * @summary Get the number of calendar days between the given dates.
 *
 * @description
 * Get the number of calendar days between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of calendar days
 *
 * @example
 * // How many calendar days are between
 * // 2 July 2011 23:00:00 and 2 July 2012 00:00:00?
 * var result = differenceInCalendarDays(
 *   new Date(2012, 6, 2, 0, 0),
 *   new Date(2011, 6, 2, 23, 0)
 * )
 * //=> 366
 */
function differenceInCalendarDays (dirtyDateLeft, dirtyDateRight) {
  var startOfDayLeft = start_of_day(dirtyDateLeft);
  var startOfDayRight = start_of_day(dirtyDateRight);

  var timestampLeft = startOfDayLeft.getTime() -
    startOfDayLeft.getTimezoneOffset() * MILLISECONDS_IN_MINUTE$2;
  var timestampRight = startOfDayRight.getTime() -
    startOfDayRight.getTimezoneOffset() * MILLISECONDS_IN_MINUTE$2;

  // Round the number of days to the nearest integer
  // because the number of milliseconds in a day is not constant
  // (e.g. it's different in the day of the daylight saving time clock shift)
  return Math.round((timestampLeft - timestampRight) / MILLISECONDS_IN_DAY)
}

var difference_in_calendar_days = differenceInCalendarDays;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Set the ISO week-numbering year to the given date.
 *
 * @description
 * Set the ISO week-numbering year to the given date,
 * saving the week number and the weekday number.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} isoYear - the ISO week-numbering year of the new date
 * @returns {Date} the new date with the ISO week-numbering year setted
 *
 * @example
 * // Set ISO week-numbering year 2007 to 29 December 2008:
 * var result = setISOYear(new Date(2008, 11, 29), 2007)
 * //=> Mon Jan 01 2007 00:00:00
 */
function setISOYear (dirtyDate, dirtyISOYear) {
  var date = parse_1(dirtyDate);
  var isoYear = Number(dirtyISOYear);
  var diff = difference_in_calendar_days(date, start_of_iso_year(date));
  var fourthOfJanuary = new Date(0);
  fourthOfJanuary.setFullYear(isoYear, 0, 4);
  fourthOfJanuary.setHours(0, 0, 0, 0);
  date = start_of_iso_year(fourthOfJanuary);
  date.setDate(date.getDate() + diff);
  return date
}

var set_iso_year = setISOYear;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Add the specified number of ISO week-numbering years to the given date.
 *
 * @description
 * Add the specified number of ISO week-numbering years to the given date.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of ISO week-numbering years to be added
 * @returns {Date} the new date with the ISO week-numbering years added
 *
 * @example
 * // Add 5 ISO week-numbering years to 2 July 2010:
 * var result = addISOYears(new Date(2010, 6, 2), 5)
 * //=> Fri Jun 26 2015 00:00:00
 */
function addISOYears (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  return set_iso_year(dirtyDate, get_iso_year(dirtyDate) + amount)
}

var add_iso_years = addISOYears;

var MILLISECONDS_IN_MINUTE$3 = 60000;

/**
 * @category Minute Helpers
 * @summary Add the specified number of minutes to the given date.
 *
 * @description
 * Add the specified number of minutes to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of minutes to be added
 * @returns {Date} the new date with the minutes added
 *
 * @example
 * // Add 30 minutes to 10 July 2014 12:00:00:
 * var result = addMinutes(new Date(2014, 6, 10, 12, 0), 30)
 * //=> Thu Jul 10 2014 12:30:00
 */
function addMinutes (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  return add_milliseconds(dirtyDate, amount * MILLISECONDS_IN_MINUTE$3)
}

var add_minutes = addMinutes;

/**
 * @category Month Helpers
 * @summary Get the number of days in a month of the given date.
 *
 * @description
 * Get the number of days in a month of the given date.
 *
 * @param {Date|String|Number} date - the given date
 * @returns {Number} the number of days in a month
 *
 * @example
 * // How many days are in February 2000?
 * var result = getDaysInMonth(new Date(2000, 1))
 * //=> 29
 */
function getDaysInMonth (dirtyDate) {
  var date = parse_1(dirtyDate);
  var year = date.getFullYear();
  var monthIndex = date.getMonth();
  var lastDayOfMonth = new Date(0);
  lastDayOfMonth.setFullYear(year, monthIndex + 1, 0);
  lastDayOfMonth.setHours(0, 0, 0, 0);
  return lastDayOfMonth.getDate()
}

var get_days_in_month = getDaysInMonth;

/**
 * @category Month Helpers
 * @summary Add the specified number of months to the given date.
 *
 * @description
 * Add the specified number of months to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of months to be added
 * @returns {Date} the new date with the months added
 *
 * @example
 * // Add 5 months to 1 September 2014:
 * var result = addMonths(new Date(2014, 8, 1), 5)
 * //=> Sun Feb 01 2015 00:00:00
 */
function addMonths (dirtyDate, dirtyAmount) {
  var date = parse_1(dirtyDate);
  var amount = Number(dirtyAmount);
  var desiredMonth = date.getMonth() + amount;
  var dateWithDesiredMonth = new Date(0);
  dateWithDesiredMonth.setFullYear(date.getFullYear(), desiredMonth, 1);
  dateWithDesiredMonth.setHours(0, 0, 0, 0);
  var daysInMonth = get_days_in_month(dateWithDesiredMonth);
  // Set the last day of the new month
  // if the original date was the last day of the longer month
  date.setMonth(desiredMonth, Math.min(daysInMonth, date.getDate()));
  return date
}

var add_months = addMonths;

/**
 * @category Quarter Helpers
 * @summary Add the specified number of year quarters to the given date.
 *
 * @description
 * Add the specified number of year quarters to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of quarters to be added
 * @returns {Date} the new date with the quarters added
 *
 * @example
 * // Add 1 quarter to 1 September 2014:
 * var result = addQuarters(new Date(2014, 8, 1), 1)
 * //=> Mon Dec 01 2014 00:00:00
 */
function addQuarters (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  var months = amount * 3;
  return add_months(dirtyDate, months)
}

var add_quarters = addQuarters;

/**
 * @category Second Helpers
 * @summary Add the specified number of seconds to the given date.
 *
 * @description
 * Add the specified number of seconds to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of seconds to be added
 * @returns {Date} the new date with the seconds added
 *
 * @example
 * // Add 30 seconds to 10 July 2014 12:45:00:
 * var result = addSeconds(new Date(2014, 6, 10, 12, 45, 0), 30)
 * //=> Thu Jul 10 2014 12:45:30
 */
function addSeconds (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  return add_milliseconds(dirtyDate, amount * 1000)
}

var add_seconds = addSeconds;

/**
 * @category Week Helpers
 * @summary Add the specified number of weeks to the given date.
 *
 * @description
 * Add the specified number of week to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of weeks to be added
 * @returns {Date} the new date with the weeks added
 *
 * @example
 * // Add 4 weeks to 1 September 2014:
 * var result = addWeeks(new Date(2014, 8, 1), 4)
 * //=> Mon Sep 29 2014 00:00:00
 */
function addWeeks (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  var days = amount * 7;
  return add_days(dirtyDate, days)
}

var add_weeks = addWeeks;

/**
 * @category Year Helpers
 * @summary Add the specified number of years to the given date.
 *
 * @description
 * Add the specified number of years to the given date.
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of years to be added
 * @returns {Date} the new date with the years added
 *
 * @example
 * // Add 5 years to 1 September 2014:
 * var result = addYears(new Date(2014, 8, 1), 5)
 * //=> Sun Sep 01 2019 00:00:00
 */
function addYears (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  return add_months(dirtyDate, amount * 12)
}

var add_years = addYears;

/**
 * @category Range Helpers
 * @summary Is the given date range overlapping with another date range?
 *
 * @description
 * Is the given date range overlapping with another date range?
 *
 * @param {Date|String|Number} initialRangeStartDate - the start of the initial range
 * @param {Date|String|Number} initialRangeEndDate - the end of the initial range
 * @param {Date|String|Number} comparedRangeStartDate - the start of the range to compare it with
 * @param {Date|String|Number} comparedRangeEndDate - the end of the range to compare it with
 * @returns {Boolean} whether the date ranges are overlapping
 * @throws {Error} startDate of a date range cannot be after its endDate
 *
 * @example
 * // For overlapping date ranges:
 * areRangesOverlapping(
 *   new Date(2014, 0, 10), new Date(2014, 0, 20), new Date(2014, 0, 17), new Date(2014, 0, 21)
 * )
 * //=> true
 *
 * @example
 * // For non-overlapping date ranges:
 * areRangesOverlapping(
 *   new Date(2014, 0, 10), new Date(2014, 0, 20), new Date(2014, 0, 21), new Date(2014, 0, 22)
 * )
 * //=> false
 */
function areRangesOverlapping (dirtyInitialRangeStartDate, dirtyInitialRangeEndDate, dirtyComparedRangeStartDate, dirtyComparedRangeEndDate) {
  var initialStartTime = parse_1(dirtyInitialRangeStartDate).getTime();
  var initialEndTime = parse_1(dirtyInitialRangeEndDate).getTime();
  var comparedStartTime = parse_1(dirtyComparedRangeStartDate).getTime();
  var comparedEndTime = parse_1(dirtyComparedRangeEndDate).getTime();

  if (initialStartTime > initialEndTime || comparedStartTime > comparedEndTime) {
    throw new Error('The start of the range cannot be after the end of the range')
  }

  return initialStartTime < comparedEndTime && comparedStartTime < initialEndTime
}

var are_ranges_overlapping = areRangesOverlapping;

/**
 * @category Common Helpers
 * @summary Return an index of the closest date from the array comparing to the given date.
 *
 * @description
 * Return an index of the closest date from the array comparing to the given date.
 *
 * @param {Date|String|Number} dateToCompare - the date to compare with
 * @param {Date[]|String[]|Number[]} datesArray - the array to search
 * @returns {Number} an index of the date closest to the given date
 * @throws {TypeError} the second argument must be an instance of Array
 *
 * @example
 * // Which date is closer to 6 September 2015?
 * var dateToCompare = new Date(2015, 8, 6)
 * var datesArray = [
 *   new Date(2015, 0, 1),
 *   new Date(2016, 0, 1),
 *   new Date(2017, 0, 1)
 * ]
 * var result = closestIndexTo(dateToCompare, datesArray)
 * //=> 1
 */
function closestIndexTo (dirtyDateToCompare, dirtyDatesArray) {
  if (!(dirtyDatesArray instanceof Array)) {
    throw new TypeError(toString.call(dirtyDatesArray) + ' is not an instance of Array')
  }

  var dateToCompare = parse_1(dirtyDateToCompare);
  var timeToCompare = dateToCompare.getTime();

  var result;
  var minDistance;

  dirtyDatesArray.forEach(function (dirtyDate, index) {
    var currentDate = parse_1(dirtyDate);
    var distance = Math.abs(timeToCompare - currentDate.getTime());
    if (result === undefined || distance < minDistance) {
      result = index;
      minDistance = distance;
    }
  });

  return result
}

var closest_index_to = closestIndexTo;

/**
 * @category Common Helpers
 * @summary Return a date from the array closest to the given date.
 *
 * @description
 * Return a date from the array closest to the given date.
 *
 * @param {Date|String|Number} dateToCompare - the date to compare with
 * @param {Date[]|String[]|Number[]} datesArray - the array to search
 * @returns {Date} the date from the array closest to the given date
 * @throws {TypeError} the second argument must be an instance of Array
 *
 * @example
 * // Which date is closer to 6 September 2015: 1 January 2000 or 1 January 2030?
 * var dateToCompare = new Date(2015, 8, 6)
 * var result = closestTo(dateToCompare, [
 *   new Date(2000, 0, 1),
 *   new Date(2030, 0, 1)
 * ])
 * //=> Tue Jan 01 2030 00:00:00
 */
function closestTo (dirtyDateToCompare, dirtyDatesArray) {
  if (!(dirtyDatesArray instanceof Array)) {
    throw new TypeError(toString.call(dirtyDatesArray) + ' is not an instance of Array')
  }

  var dateToCompare = parse_1(dirtyDateToCompare);
  var timeToCompare = dateToCompare.getTime();

  var result;
  var minDistance;

  dirtyDatesArray.forEach(function (dirtyDate) {
    var currentDate = parse_1(dirtyDate);
    var distance = Math.abs(timeToCompare - currentDate.getTime());
    if (result === undefined || distance < minDistance) {
      result = currentDate;
      minDistance = distance;
    }
  });

  return result
}

var closest_to = closestTo;

/**
 * @category Common Helpers
 * @summary Compare the two dates and return -1, 0 or 1.
 *
 * @description
 * Compare the two dates and return 1 if the first date is after the second,
 * -1 if the first date is before the second or 0 if dates are equal.
 *
 * @param {Date|String|Number} dateLeft - the first date to compare
 * @param {Date|String|Number} dateRight - the second date to compare
 * @returns {Number} the result of the comparison
 *
 * @example
 * // Compare 11 February 1987 and 10 July 1989:
 * var result = compareAsc(
 *   new Date(1987, 1, 11),
 *   new Date(1989, 6, 10)
 * )
 * //=> -1
 *
 * @example
 * // Sort the array of dates:
 * var result = [
 *   new Date(1995, 6, 2),
 *   new Date(1987, 1, 11),
 *   new Date(1989, 6, 10)
 * ].sort(compareAsc)
 * //=> [
 * //   Wed Feb 11 1987 00:00:00,
 * //   Mon Jul 10 1989 00:00:00,
 * //   Sun Jul 02 1995 00:00:00
 * // ]
 */
function compareAsc (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var timeLeft = dateLeft.getTime();
  var dateRight = parse_1(dirtyDateRight);
  var timeRight = dateRight.getTime();

  if (timeLeft < timeRight) {
    return -1
  } else if (timeLeft > timeRight) {
    return 1
  } else {
    return 0
  }
}

var compare_asc = compareAsc;

/**
 * @category Common Helpers
 * @summary Compare the two dates reverse chronologically and return -1, 0 or 1.
 *
 * @description
 * Compare the two dates and return -1 if the first date is after the second,
 * 1 if the first date is before the second or 0 if dates are equal.
 *
 * @param {Date|String|Number} dateLeft - the first date to compare
 * @param {Date|String|Number} dateRight - the second date to compare
 * @returns {Number} the result of the comparison
 *
 * @example
 * // Compare 11 February 1987 and 10 July 1989 reverse chronologically:
 * var result = compareDesc(
 *   new Date(1987, 1, 11),
 *   new Date(1989, 6, 10)
 * )
 * //=> 1
 *
 * @example
 * // Sort the array of dates in reverse chronological order:
 * var result = [
 *   new Date(1995, 6, 2),
 *   new Date(1987, 1, 11),
 *   new Date(1989, 6, 10)
 * ].sort(compareDesc)
 * //=> [
 * //   Sun Jul 02 1995 00:00:00,
 * //   Mon Jul 10 1989 00:00:00,
 * //   Wed Feb 11 1987 00:00:00
 * // ]
 */
function compareDesc (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var timeLeft = dateLeft.getTime();
  var dateRight = parse_1(dirtyDateRight);
  var timeRight = dateRight.getTime();

  if (timeLeft > timeRight) {
    return -1
  } else if (timeLeft < timeRight) {
    return 1
  } else {
    return 0
  }
}

var compare_desc = compareDesc;

var MILLISECONDS_IN_MINUTE$4 = 60000;
var MILLISECONDS_IN_WEEK = 604800000;

/**
 * @category ISO Week Helpers
 * @summary Get the number of calendar ISO weeks between the given dates.
 *
 * @description
 * Get the number of calendar ISO weeks between the given dates.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of calendar ISO weeks
 *
 * @example
 * // How many calendar ISO weeks are between 6 July 2014 and 21 July 2014?
 * var result = differenceInCalendarISOWeeks(
 *   new Date(2014, 6, 21),
 *   new Date(2014, 6, 6)
 * )
 * //=> 3
 */
function differenceInCalendarISOWeeks (dirtyDateLeft, dirtyDateRight) {
  var startOfISOWeekLeft = start_of_iso_week(dirtyDateLeft);
  var startOfISOWeekRight = start_of_iso_week(dirtyDateRight);

  var timestampLeft = startOfISOWeekLeft.getTime() -
    startOfISOWeekLeft.getTimezoneOffset() * MILLISECONDS_IN_MINUTE$4;
  var timestampRight = startOfISOWeekRight.getTime() -
    startOfISOWeekRight.getTimezoneOffset() * MILLISECONDS_IN_MINUTE$4;

  // Round the number of days to the nearest integer
  // because the number of milliseconds in a week is not constant
  // (e.g. it's different in the week of the daylight saving time clock shift)
  return Math.round((timestampLeft - timestampRight) / MILLISECONDS_IN_WEEK)
}

var difference_in_calendar_iso_weeks = differenceInCalendarISOWeeks;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Get the number of calendar ISO week-numbering years between the given dates.
 *
 * @description
 * Get the number of calendar ISO week-numbering years between the given dates.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of calendar ISO week-numbering years
 *
 * @example
 * // How many calendar ISO week-numbering years are 1 January 2010 and 1 January 2012?
 * var result = differenceInCalendarISOYears(
 *   new Date(2012, 0, 1),
 *   new Date(2010, 0, 1)
 * )
 * //=> 2
 */
function differenceInCalendarISOYears (dirtyDateLeft, dirtyDateRight) {
  return get_iso_year(dirtyDateLeft) - get_iso_year(dirtyDateRight)
}

var difference_in_calendar_iso_years = differenceInCalendarISOYears;

/**
 * @category Month Helpers
 * @summary Get the number of calendar months between the given dates.
 *
 * @description
 * Get the number of calendar months between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of calendar months
 *
 * @example
 * // How many calendar months are between 31 January 2014 and 1 September 2014?
 * var result = differenceInCalendarMonths(
 *   new Date(2014, 8, 1),
 *   new Date(2014, 0, 31)
 * )
 * //=> 8
 */
function differenceInCalendarMonths (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var dateRight = parse_1(dirtyDateRight);

  var yearDiff = dateLeft.getFullYear() - dateRight.getFullYear();
  var monthDiff = dateLeft.getMonth() - dateRight.getMonth();

  return yearDiff * 12 + monthDiff
}

var difference_in_calendar_months = differenceInCalendarMonths;

/**
 * @category Quarter Helpers
 * @summary Get the year quarter of the given date.
 *
 * @description
 * Get the year quarter of the given date.
 *
 * @param {Date|String|Number} date - the given date
 * @returns {Number} the quarter
 *
 * @example
 * // Which quarter is 2 July 2014?
 * var result = getQuarter(new Date(2014, 6, 2))
 * //=> 3
 */
function getQuarter (dirtyDate) {
  var date = parse_1(dirtyDate);
  var quarter = Math.floor(date.getMonth() / 3) + 1;
  return quarter
}

var get_quarter = getQuarter;

/**
 * @category Quarter Helpers
 * @summary Get the number of calendar quarters between the given dates.
 *
 * @description
 * Get the number of calendar quarters between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of calendar quarters
 *
 * @example
 * // How many calendar quarters are between 31 December 2013 and 2 July 2014?
 * var result = differenceInCalendarQuarters(
 *   new Date(2014, 6, 2),
 *   new Date(2013, 11, 31)
 * )
 * //=> 3
 */
function differenceInCalendarQuarters (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var dateRight = parse_1(dirtyDateRight);

  var yearDiff = dateLeft.getFullYear() - dateRight.getFullYear();
  var quarterDiff = get_quarter(dateLeft) - get_quarter(dateRight);

  return yearDiff * 4 + quarterDiff
}

var difference_in_calendar_quarters = differenceInCalendarQuarters;

var MILLISECONDS_IN_MINUTE$5 = 60000;
var MILLISECONDS_IN_WEEK$1 = 604800000;

/**
 * @category Week Helpers
 * @summary Get the number of calendar weeks between the given dates.
 *
 * @description
 * Get the number of calendar weeks between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @param {Object} [options] - the object with options
 * @param {Number} [options.weekStartsOn=0] - the index of the first day of the week (0 - Sunday)
 * @returns {Number} the number of calendar weeks
 *
 * @example
 * // How many calendar weeks are between 5 July 2014 and 20 July 2014?
 * var result = differenceInCalendarWeeks(
 *   new Date(2014, 6, 20),
 *   new Date(2014, 6, 5)
 * )
 * //=> 3
 *
 * @example
 * // If the week starts on Monday,
 * // how many calendar weeks are between 5 July 2014 and 20 July 2014?
 * var result = differenceInCalendarWeeks(
 *   new Date(2014, 6, 20),
 *   new Date(2014, 6, 5),
 *   {weekStartsOn: 1}
 * )
 * //=> 2
 */
function differenceInCalendarWeeks (dirtyDateLeft, dirtyDateRight, dirtyOptions) {
  var startOfWeekLeft = start_of_week(dirtyDateLeft, dirtyOptions);
  var startOfWeekRight = start_of_week(dirtyDateRight, dirtyOptions);

  var timestampLeft = startOfWeekLeft.getTime() -
    startOfWeekLeft.getTimezoneOffset() * MILLISECONDS_IN_MINUTE$5;
  var timestampRight = startOfWeekRight.getTime() -
    startOfWeekRight.getTimezoneOffset() * MILLISECONDS_IN_MINUTE$5;

  // Round the number of days to the nearest integer
  // because the number of milliseconds in a week is not constant
  // (e.g. it's different in the week of the daylight saving time clock shift)
  return Math.round((timestampLeft - timestampRight) / MILLISECONDS_IN_WEEK$1)
}

var difference_in_calendar_weeks = differenceInCalendarWeeks;

/**
 * @category Year Helpers
 * @summary Get the number of calendar years between the given dates.
 *
 * @description
 * Get the number of calendar years between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of calendar years
 *
 * @example
 * // How many calendar years are between 31 December 2013 and 11 February 2015?
 * var result = differenceInCalendarYears(
 *   new Date(2015, 1, 11),
 *   new Date(2013, 11, 31)
 * )
 * //=> 2
 */
function differenceInCalendarYears (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var dateRight = parse_1(dirtyDateRight);

  return dateLeft.getFullYear() - dateRight.getFullYear()
}

var difference_in_calendar_years = differenceInCalendarYears;

/**
 * @category Day Helpers
 * @summary Get the number of full days between the given dates.
 *
 * @description
 * Get the number of full days between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of full days
 *
 * @example
 * // How many full days are between
 * // 2 July 2011 23:00:00 and 2 July 2012 00:00:00?
 * var result = differenceInDays(
 *   new Date(2012, 6, 2, 0, 0),
 *   new Date(2011, 6, 2, 23, 0)
 * )
 * //=> 365
 */
function differenceInDays (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var dateRight = parse_1(dirtyDateRight);

  var sign = compare_asc(dateLeft, dateRight);
  var difference = Math.abs(difference_in_calendar_days(dateLeft, dateRight));
  dateLeft.setDate(dateLeft.getDate() - sign * difference);

  // Math.abs(diff in full days - diff in calendar days) === 1 if last calendar day is not full
  // If so, result must be decreased by 1 in absolute value
  var isLastDayNotFull = compare_asc(dateLeft, dateRight) === -sign;
  return sign * (difference - isLastDayNotFull)
}

var difference_in_days = differenceInDays;

/**
 * @category Millisecond Helpers
 * @summary Get the number of milliseconds between the given dates.
 *
 * @description
 * Get the number of milliseconds between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of milliseconds
 *
 * @example
 * // How many milliseconds are between
 * // 2 July 2014 12:30:20.600 and 2 July 2014 12:30:21.700?
 * var result = differenceInMilliseconds(
 *   new Date(2014, 6, 2, 12, 30, 21, 700),
 *   new Date(2014, 6, 2, 12, 30, 20, 600)
 * )
 * //=> 1100
 */
function differenceInMilliseconds (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var dateRight = parse_1(dirtyDateRight);
  return dateLeft.getTime() - dateRight.getTime()
}

var difference_in_milliseconds = differenceInMilliseconds;

var MILLISECONDS_IN_HOUR$2 = 3600000;

/**
 * @category Hour Helpers
 * @summary Get the number of hours between the given dates.
 *
 * @description
 * Get the number of hours between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of hours
 *
 * @example
 * // How many hours are between 2 July 2014 06:50:00 and 2 July 2014 19:00:00?
 * var result = differenceInHours(
 *   new Date(2014, 6, 2, 19, 0),
 *   new Date(2014, 6, 2, 6, 50)
 * )
 * //=> 12
 */
function differenceInHours (dirtyDateLeft, dirtyDateRight) {
  var diff = difference_in_milliseconds(dirtyDateLeft, dirtyDateRight) / MILLISECONDS_IN_HOUR$2;
  return diff > 0 ? Math.floor(diff) : Math.ceil(diff)
}

var difference_in_hours = differenceInHours;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Subtract the specified number of ISO week-numbering years from the given date.
 *
 * @description
 * Subtract the specified number of ISO week-numbering years from the given date.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} date - the date to be changed
 * @param {Number} amount - the amount of ISO week-numbering years to be subtracted
 * @returns {Date} the new date with the ISO week-numbering years subtracted
 *
 * @example
 * // Subtract 5 ISO week-numbering years from 1 September 2014:
 * var result = subISOYears(new Date(2014, 8, 1), 5)
 * //=> Mon Aug 31 2009 00:00:00
 */
function subISOYears (dirtyDate, dirtyAmount) {
  var amount = Number(dirtyAmount);
  return add_iso_years(dirtyDate, -amount)
}

var sub_iso_years = subISOYears;

/**
 * @category ISO Week-Numbering Year Helpers
 * @summary Get the number of full ISO week-numbering years between the given dates.
 *
 * @description
 * Get the number of full ISO week-numbering years between the given dates.
 *
 * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of full ISO week-numbering years
 *
 * @example
 * // How many full ISO week-numbering years are between 1 January 2010 and 1 January 2012?
 * var result = differenceInISOYears(
 *   new Date(2012, 0, 1),
 *   new Date(2010, 0, 1)
 * )
 * //=> 1
 */
function differenceInISOYears (dirtyDateLeft, dirtyDateRight) {
  var dateLeft = parse_1(dirtyDateLeft);
  var dateRight = parse_1(dirtyDateRight);

  var sign = compare_asc(dateLeft, dateRight);
  var difference = Math.abs(difference_in_calendar_iso_years(dateLeft, dateRight));
  dateLeft = sub_iso_years(dateLeft, sign * difference);

  // Math.abs(diff in full ISO years - diff in calendar ISO years) === 1
  // if last calendar ISO year is not full
  // If so, result must be decreased by 1 in absolute value
  var isLastISOYearNotFull = compare_asc(dateLeft, dateRight) === -sign;
  return sign * (difference - isLastISOYearNotFull)
}

var difference_in_iso_years = differenceInISOYears;

var MILLISECONDS_IN_MINUTE$6 = 60000;

/**
 * @category Minute Helpers
 * @summary Get the number of minutes between the given dates.
 *
 * @description
 * Get the number of minutes between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of minutes
 *
 * @example
 * // How many minutes are between 2 July 2014 12:07:59 and 2 July 2014 12:20:00?
 * var result = differenceInMinutes(
 *   new Date(2014, 6, 2, 12, 20, 0),
 *   new Date(2014, 6, 2, 12, 7, 59)
 * )
 * //=> 12
 */
function differenceInMinutes (dirtyDateLeft, dirtyDateRight) {
  var diff = difference_in_milliseconds(dirtyDateLeft, dirtyDateRight) / MILLISECONDS_IN_MINUTE$6;
  return diff > 0 ? Math.floor(diff) : Math.ceil(diff)
}

var difference_in_minutes = differenceInMinutes;

/**
 * @category Month Helpers
 * @summary Get the number of full months between the given dates.
 *
 * @description
 * Get the number of full months between the given dates.
 *
 * @param {Date|String|Number} dateLeft - the later date
 * @param {Date|String|Number} dateRight - the earlier date
 * @returns {Number} the number of ful