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diff --git a/date-fns/src/getWeekYear/index.ts b/date-fns/src/getWeekYear/index.ts
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+import startOfWeek from '../startOfWeek/index'
+import toDate from '../toDate/index'
+import toInteger from '../_lib/toInteger/index'
+import requiredArgs from '../_lib/requiredArgs/index'
+import {
+  WeekStartOptions,
+  LocaleOptions,
+  FirstWeekContainsDateOptions,
+} from '../types'
+
+/**
+ * @name getWeekYear
+ * @category Week-Numbering Year Helpers
+ * @summary Get the local week-numbering year of the given date.
+ *
+ * @description
+ * Get the local week-numbering year of the given date.
+ * The exact calculation depends on the values of
+ * `options.weekStartsOn` (which is the index of the first day of the week)
+ * and `options.firstWeekContainsDate` (which is the day of January, which is always in
+ * the first week of the week-numbering year)
+ *
+ * Week numbering: https://en.wikipedia.org/wiki/Week#Week_numbering
+ *
+ * ### 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)
+ * @param {1|2|3|4|5|6|7} [options.firstWeekContainsDate=1] - the day of January, which is always in the first week of the year
+ * @returns {Number} the local week-numbering year
+ * @throws {TypeError} 1 argument required
+ * @throws {RangeError} `options.weekStartsOn` must be between 0 and 6
+ * @throws {RangeError} `options.firstWeekContainsDate` must be between 1 and 7
+ *
+ * @example
+ * // Which week numbering year is 26 December 2004 with the default settings?
+ * const result = getWeekYear(new Date(2004, 11, 26))
+ * //=> 2005
+ *
+ * @example
+ * // Which week numbering year is 26 December 2004 if week starts on Saturday?
+ * const result = getWeekYear(new Date(2004, 11, 26), { weekStartsOn: 6 })
+ * //=> 2004
+ *
+ * @example
+ * // Which week numbering year is 26 December 2004 if the first week contains 4 January?
+ * const result = getWeekYear(new Date(2004, 11, 26), { firstWeekContainsDate: 4 })
+ * //=> 2004
+ */
+export default function getWeekYear(
+  dirtyDate: Date | number,
+  options?: LocaleOptions & WeekStartOptions & FirstWeekContainsDateOptions
+): number {
+  requiredArgs(1, arguments)
+
+  const date = toDate(dirtyDate)
+  const year = date.getFullYear()
+
+  const localeFirstWeekContainsDate =
+    options?.locale?.options?.firstWeekContainsDate
+  const defaultFirstWeekContainsDate =
+    localeFirstWeekContainsDate == null
+      ? 1
+      : toInteger(localeFirstWeekContainsDate)
+  const firstWeekContainsDate =
+    options?.firstWeekContainsDate == null
+      ? defaultFirstWeekContainsDate
+      : toInteger(options.firstWeekContainsDate)
+
+  // Test if weekStartsOn is between 1 and 7 _and_ is not NaN
+  if (!(firstWeekContainsDate >= 1 && firstWeekContainsDate <= 7)) {
+    throw new RangeError(
+      'firstWeekContainsDate must be between 1 and 7 inclusively'
+    )
+  }
+
+  const firstWeekOfNextYear = new Date(0)
+  firstWeekOfNextYear.setFullYear(year + 1, 0, firstWeekContainsDate)
+  firstWeekOfNextYear.setHours(0, 0, 0, 0)
+  const startOfNextYear = startOfWeek(firstWeekOfNextYear, options)
+
+  const firstWeekOfThisYear = new Date(0)
+  firstWeekOfThisYear.setFullYear(year, 0, firstWeekContainsDate)
+  firstWeekOfThisYear.setHours(0, 0, 0, 0)
+  const startOfThisYear = startOfWeek(firstWeekOfThisYear, options)
+
+  if (date.getTime() >= startOfNextYear.getTime()) {
+    return year + 1
+  } else if (date.getTime() >= startOfThisYear.getTime()) {
+    return year
+  } else {
+    return year - 1
+  }
+}