v1.0 with SW PWA enabled

frontend/node_modules/date-fns/closestIndexTo.js

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+"use strict";
+exports.closestIndexTo = closestIndexTo;
+var _index = require("./toDate.js");
+
+/**
+ * @name closestIndexTo
+ * @category Common Helpers
+ * @summary Return an index of the closest date from the array comparing to the given date.
+ *
+ * @description
+ * Return an index of the closest date from the array comparing to 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 dateToCompare - The date to compare with
+ * @param dates - The array to search
+ *
+ * @returns An index of the date closest to the given date or undefined if no valid value is given
+ *
+ * @example
+ * // Which date is closer to 6 September 2015?
+ * const dateToCompare = new Date(2015, 8, 6)
+ * const datesArray = [
+ *   new Date(2015, 0, 1),
+ *   new Date(2016, 0, 1),
+ *   new Date(2017, 0, 1)
+ * ]
+ * const result = closestIndexTo(dateToCompare, datesArray)
+ * //=> 1
+ */
+function closestIndexTo(dateToCompare, dates) {
+  const date = (0, _index.toDate)(dateToCompare);
+
+  if (isNaN(Number(date))) return NaN;
+
+  const timeToCompare = date.getTime();
+
+  let result;
+  let minDistance;
+  dates.forEach(function (dirtyDate, index) {
+    const currentDate = (0, _index.toDate)(dirtyDate);
+
+    if (isNaN(Number(currentDate))) {
+      result = NaN;
+      minDistance = NaN;
+      return;
+    }
+
+    const distance = Math.abs(timeToCompare - currentDate.getTime());
+    if (result == null || distance < minDistance) {
+      result = index;
+      minDistance = distance;
+    }
+  });
+
+  return result;
+}