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backend/node_modules/date-fns/differenceInWeeks/index.js

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+"use strict";
+
+var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault").default;
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = differenceInWeeks;
+var _index = _interopRequireDefault(require("../differenceInDays/index.js"));
+var _index2 = _interopRequireDefault(require("../_lib/requiredArgs/index.js"));
+var _index3 = require("../_lib/roundingMethods/index.js");
+/**
+ * @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.floor(differenceInHours(dateLeft, dateRight)/(7*24))|0`.
+ *
+ *
+ * @param {Date|Number} dateLeft - the later date
+ * @param {Date|Number} dateRight - the earlier date
+ * @param {Object} [options] - an object with options.
+ * @param {String} [options.roundingMethod='trunc'] - a rounding method (`ceil`, `floor`, `round` or `trunc`)
+ * @returns {Number} the number of full weeks
+ * @throws {TypeError} 2 arguments required
+ *
+ * @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
+ *
+ * // 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
+ */
+function differenceInWeeks(dateLeft, dateRight, options) {
+  (0, _index2.default)(2, arguments);
+  var diff = (0, _index.default)(dateLeft, dateRight) / 7;
+  return (0, _index3.getRoundingMethod)(options === null || options === void 0 ? void 0 : options.roundingMethod)(diff);
+}
+module.exports = exports.default;