📝 Commit Details:

backend/node_modules/date-fns/differenceInWeeks.js

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+import { getRoundingMethod } from "./_lib/getRoundingMethod.js";
+import { differenceInDays } from "./differenceInDays.js";
+
+/**
+ * The {@link differenceInWeeks} function options.
+ */
+
+/**
+ * @name differenceInWeeks
+ * @category Week Helpers
+ * @summary Get the number of full weeks between the given dates.
+ *
+ * @description
+ * Get the number of full weeks between two dates. Fractional weeks are
+ * truncated towards zero by default.
+ *
+ * One "full week" is the distance between a local time in one day to the same
+ * local time 7 days earlier or later. A full week can sometimes be less than
+ * or more than 7*24 hours if a daylight savings change happens between two dates.
+ *
+ * To ignore DST and only measure exact 7*24-hour periods, use this instead:
+ * `Math.trunc(differenceInHours(dateLeft, dateRight)/(7*24))|0`.
+ *
+ * @param laterDate - The later date
+ * @param earlierDate - The earlier date
+ * @param options - An object with options
+ *
+ * @returns The number of full weeks
+ *
+ * @example
+ * // How many full weeks are between 5 July 2014 and 20 July 2014?
+ * const result = differenceInWeeks(new Date(2014, 6, 20), new Date(2014, 6, 5))
+ * //=> 2
+ *
+ * @example
+ * // How many full weeks are between
+ * // 1 March 2020 0:00 and 6 June 2020 0:00 ?
+ * // Note: because local time is used, the
+ * // result will always be 8 weeks (54 days),
+ * // even if DST starts and the period has
+ * // only 54*24-1 hours.
+ * const result = differenceInWeeks(
+ *   new Date(2020, 5, 1),
+ *   new Date(2020, 2, 6)
+ * )
+ * //=> 8
+ */
+export function differenceInWeeks(laterDate, earlierDate, options) {
+  const diff = differenceInDays(laterDate, earlierDate, options) / 7;
+  return getRoundingMethod(options?.roundingMethod)(diff);
+}
+
+// Fallback for modularized imports:
+export default differenceInWeeks;