📝 Commit Details:

backend/node_modules/date-fns/addBusinessDays.js

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+import { constructFrom } from "./constructFrom.js";
+import { isSaturday } from "./isSaturday.js";
+import { isSunday } from "./isSunday.js";
+import { isWeekend } from "./isWeekend.js";
+import { toDate } from "./toDate.js";
+
+/**
+ * The {@link addBusinessDays} function options.
+ */
+
+/**
+ * @name addBusinessDays
+ * @category Day Helpers
+ * @summary Add the specified number of business days (mon - fri) to the given date.
+ *
+ * @description
+ * Add the specified number of business days (mon - fri) to the given date, ignoring weekends.
+ *
+ * @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).
+ * @typeParam ResultDate - The result `Date` type, it is the type returned from the context function if it is passed, or inferred from the arguments.
+ *
+ * @param date - The date to be changed
+ * @param amount - The amount of business days to be added.
+ * @param options - An object with options
+ *
+ * @returns The new date with the business days added
+ *
+ * @example
+ * // Add 10 business days to 1 September 2014:
+ * const result = addBusinessDays(new Date(2014, 8, 1), 10)
+ * //=> Mon Sep 15 2014 00:00:00 (skipped weekend days)
+ */
+export function addBusinessDays(date, amount, options) {
+  const _date = toDate(date, options?.in);
+  const startedOnWeekend = isWeekend(_date, options);
+
+  if (isNaN(amount)) return constructFrom(options?.in, NaN);
+
+  const hours = _date.getHours();
+  const sign = amount < 0 ? -1 : 1;
+  const fullWeeks = Math.trunc(amount / 5);
+
+  _date.setDate(_date.getDate() + fullWeeks * 7);
+
+  // Get remaining days not part of a full week
+  let restDays = Math.abs(amount % 5);
+
+  // Loops over remaining days
+  while (restDays > 0) {
+    _date.setDate(_date.getDate() + sign);
+    if (!isWeekend(_date, options)) restDays -= 1;
+  }
+
+  // If the date is a weekend day and we reduce a dividable of
+  // 5 from it, we land on a weekend date.
+  // To counter this, we add days accordingly to land on the next business day
+  if (startedOnWeekend && isWeekend(_date, options) && amount !== 0) {
+    // If we're reducing days, we want to add days until we land on a weekday
+    // If we're adding days we want to reduce days until we land on a weekday
+    if (isSaturday(_date, options))
+      _date.setDate(_date.getDate() + (sign < 0 ? 2 : -1));
+    if (isSunday(_date, options))
+      _date.setDate(_date.getDate() + (sign < 0 ? 1 : -2));
+  }
+
+  // Restore hours to avoid DST lag
+  _date.setHours(hours);
+
+  return _date;
+}
+
+// Fallback for modularized imports:
+export default addBusinessDays;