📝 Commit Details:

backend/node_modules/date-fns/getISOWeeksInYear.js

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+import { addWeeks } from "./addWeeks.js";
+import { millisecondsInWeek } from "./constants.js";
+import { startOfISOWeekYear } from "./startOfISOWeekYear.js";
+
+/**
+ * The {@link getISOWeeksInYear} function options.
+ */
+
+/**
+ * @name getISOWeeksInYear
+ * @category ISO Week-Numbering Year Helpers
+ * @summary Get the number of weeks in an ISO week-numbering year of the given date.
+ *
+ * @description
+ * Get the number of weeks in an ISO week-numbering year of the given date.
+ *
+ * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
+ *
+ * @param date - The given date
+ * @param options - An object with options
+ *
+ * @returns The number of ISO weeks in a year
+ *
+ * @example
+ * // How many weeks are in ISO week-numbering year 2015?
+ * const result = getISOWeeksInYear(new Date(2015, 1, 11))
+ * //=> 53
+ */
+export function getISOWeeksInYear(date, options) {
+  const thisYear = startOfISOWeekYear(date, options);
+  const nextYear = startOfISOWeekYear(addWeeks(thisYear, 60));
+  const diff = +nextYear - +thisYear;
+
+  // Round the number of weeks 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(diff / millisecondsInWeek);
+}
+
+// Fallback for modularized imports:
+export default getISOWeeksInYear;