v1.0 with SW PWA enabled

frontend/node_modules/date-fns/lastDayOfDecade.js

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+"use strict";
+exports.lastDayOfDecade = lastDayOfDecade;
+var _index = require("./toDate.js");
+
+/**
+ * @name lastDayOfDecade
+ * @category Decade Helpers
+ * @summary Return the last day of a decade for the given date.
+ *
+ * @description
+ * Return the last day of a decade for the given 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 date - The original date
+ *
+ * @returns The last day of a decade
+ *
+ * @example
+ * // The last day of a decade for 21 December 2012 21:12:00:
+ * const result = lastDayOfDecade(new Date(2012, 11, 21, 21, 12, 00))
+ * //=> Wed Dec 31 2019 00:00:00
+ */
+function lastDayOfDecade(date) {
+  // TODO: Switch to more technical definition in of decades that start with 1
+  // end with 0. I.e. 2001-2010 instead of current 2000-2009. It's a breaking
+  // change, so it can only be done in 4.0.
+  const _date = (0, _index.toDate)(date);
+  const year = _date.getFullYear();
+  const decade = 9 + Math.floor(year / 10) * 10;
+  _date.setFullYear(decade + 1, 0, 0);
+  _date.setHours(0, 0, 0, 0);
+  return _date;
+}