v1.0 with SW PWA enabled

frontend/node_modules/date-fns/differenceInCalendarISOWeeks.js

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+"use strict";
+exports.differenceInCalendarISOWeeks = differenceInCalendarISOWeeks;
+var _index = require("./constants.js");
+var _index2 = require("./startOfISOWeek.js");
+var _index3 = require("./_lib/getTimezoneOffsetInMilliseconds.js");
+
+/**
+ * @name differenceInCalendarISOWeeks
+ * @category ISO Week Helpers
+ * @summary Get the number of calendar ISO weeks between the given dates.
+ *
+ * @description
+ * Get the number of calendar ISO weeks between the given dates.
+ *
+ * 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).
+ *
+ * @param dateLeft - The later date
+ * @param dateRight - The earlier date
+ *
+ * @returns The number of calendar ISO weeks
+ *
+ * @example
+ * // How many calendar ISO weeks are between 6 July 2014 and 21 July 2014?
+ * const result = differenceInCalendarISOWeeks(
+ *   new Date(2014, 6, 21),
+ *   new Date(2014, 6, 6)
+ * )
+ * //=> 3
+ */
+function differenceInCalendarISOWeeks(dateLeft, dateRight) {
+  const startOfISOWeekLeft = (0, _index2.startOfISOWeek)(dateLeft);
+  const startOfISOWeekRight = (0, _index2.startOfISOWeek)(dateRight);
+
+  const timestampLeft =
+    +startOfISOWeekLeft -
+    (0, _index3.getTimezoneOffsetInMilliseconds)(startOfISOWeekLeft);
+  const timestampRight =
+    +startOfISOWeekRight -
+    (0, _index3.getTimezoneOffsetInMilliseconds)(startOfISOWeekRight);
+
+  // 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(
+    (timestampLeft - timestampRight) / _index.millisecondsInWeek,
+  );
+}