FIN INIT

node_modules/date-fns/lastDayOfISOWeekYear.js

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+import { constructFrom } from "./constructFrom.js";
+import { getISOWeekYear } from "./getISOWeekYear.js";
+import { startOfISOWeek } from "./startOfISOWeek.js";
+
+/**
+ * The {@link lastDayOfISOWeekYear} function options.
+ */
+
+/**
+ * @name lastDayOfISOWeekYear
+ * @category ISO Week-Numbering Year Helpers
+ * @summary Return the last day of an ISO week-numbering year for the given date.
+ *
+ * @description
+ * Return the last day 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
+ *
+ * @typeParam DateType - The `Date` type, the function operates on. Gets inferred from passed arguments. Allows to use extensions like [`UTCDate`](https://github.com/date-fns/utc).
+ * @typeParam ResultDate - The result `Date` type, it is the type returned from the context function if it is passed, or inferred from the arguments.
+ *
+ * @param date - The original date
+ * @param options - An object with options
+ *
+ * @returns The end of an ISO week-numbering year
+ *
+ * @example
+ * // The last day of an ISO week-numbering year for 2 July 2005:
+ * const result = lastDayOfISOWeekYear(new Date(2005, 6, 2))
+ * //=> Sun Jan 01 2006 00:00:00
+ */
+export function lastDayOfISOWeekYear(date, options) {
+  const year = getISOWeekYear(date, options);
+  const fourthOfJanuary = constructFrom(options?.in || date, 0);
+  fourthOfJanuary.setFullYear(year + 1, 0, 4);
+  fourthOfJanuary.setHours(0, 0, 0, 0);
+
+  const date_ = startOfISOWeek(fourthOfJanuary, options);
+  date_.setDate(date_.getDate() - 1);
+  return date_;
+}
+
+// Fallback for modularized imports:
+export default lastDayOfISOWeekYear;