function getWeekOfMonth(date, dirtyOptions) {
  __WEBPACK_IMPORTED_MODULE_4__lib_requiredArgs_index_js__["a" /* default */](1, arguments);
  var options = dirtyOptions || {};
  var locale = options.locale;
  var localeWeekStartsOn = locale && locale.options && locale.options.weekStartsOn;
  var defaultWeekStartsOn = localeWeekStartsOn == null ? 0 : __WEBPACK_IMPORTED_MODULE_3__lib_toInteger_index_js__["a" /* default */](localeWeekStartsOn);
  var weekStartsOn = options.weekStartsOn == null ? defaultWeekStartsOn : __WEBPACK_IMPORTED_MODULE_3__lib_toInteger_index_js__["a" /* default */](options.weekStartsOn); // Test if weekStartsOn is between 0 and 6 _and_ is not NaN

  if (!(weekStartsOn >= 0 && weekStartsOn <= 6)) {
    throw new RangeError('weekStartsOn must be between 0 and 6 inclusively');
  }

  var currentDayOfMonth = __WEBPACK_IMPORTED_MODULE_0__getDate_index_js__["a" /* default */](date);

  if (isNaN(currentDayOfMonth)) {
    return currentDayOfMonth;
  }

  var startWeekDay = __WEBPACK_IMPORTED_MODULE_1__getDay_index_js__["a" /* default */](__WEBPACK_IMPORTED_MODULE_2__startOfMonth_index_js__["a" /* default */](date));
  var lastDayOfFirstWeek = 0;

  if (startWeekDay >= weekStartsOn) {
    lastDayOfFirstWeek = weekStartsOn + 7 - startWeekDay;
  } else {
    lastDayOfFirstWeek = weekStartsOn - startWeekDay;
  }

  var weekNumber = 1;

  if (currentDayOfMonth > lastDayOfFirstWeek) {
    var remainingDaysAfterFirstWeek = currentDayOfMonth - lastDayOfFirstWeek;
    weekNumber = weekNumber + Math.ceil(remainingDaysAfterFirstWeek / 7);
  }

  return weekNumber;
}
@name getWeeksInMonth
@category Week Helpers
@summary Get the number of calendar weeks a month spans.

@description
Get the number of calendar weeks the month in the given date spans.

### v2.0.0 breaking changes:

- [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes).

@param {Date|Number} date - the given date
@param {Object} [options] - an object with options.
@param {Locale} [options.locale=defaultLocale] - the locale object. See [Locale]{@link https://date-fns.org/docs/Locale}
@param {0|1|2|3|4|5|6} [options.weekStartsOn=0] - the index of the first day of the week (0 - Sunday)
@returns {Number} the number of calendar weeks
@throws {TypeError} 2 arguments required
@throws {RangeError} `options.weekStartsOn` must be between 0 and 6

@example
// How many calendar weeks does February 2015 span?
var result = getWeeksInMonth(new Date(2015, 1, 8))
//=> 4

@example
// If the week starts on Monday,
// how many calendar weeks does July 2017 span?
var result = getWeeksInMonth(new Date(2017, 6, 5), { weekStartsOn: 1 })
//=> 6