📝 Commit Details:

backend/node_modules/date-fns/differenceInCalendarDays.js

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+import { getTimezoneOffsetInMilliseconds } from "./_lib/getTimezoneOffsetInMilliseconds.js";
+import { normalizeDates } from "./_lib/normalizeDates.js";
+import { millisecondsInDay } from "./constants.js";
+import { startOfDay } from "./startOfDay.js";
+
+/**
+ * The {@link differenceInCalendarDays} function options.
+ */
+
+/**
+ * @name differenceInCalendarDays
+ * @category Day Helpers
+ * @summary Get the number of calendar days between the given dates.
+ *
+ * @description
+ * Get the number of calendar days between the given dates. This means that the times are removed
+ * from the dates and then the difference in days is calculated.
+ *
+ * @param laterDate - The later date
+ * @param earlierDate - The earlier date
+ * @param options - The options object
+ *
+ * @returns The number of calendar days
+ *
+ * @example
+ * // How many calendar days are between
+ * // 2 July 2011 23:00:00 and 2 July 2012 00:00:00?
+ * const result = differenceInCalendarDays(
+ *   new Date(2012, 6, 2, 0, 0),
+ *   new Date(2011, 6, 2, 23, 0)
+ * )
+ * //=> 366
+ * // How many calendar days are between
+ * // 2 July 2011 23:59:00 and 3 July 2011 00:01:00?
+ * const result = differenceInCalendarDays(
+ *   new Date(2011, 6, 3, 0, 1),
+ *   new Date(2011, 6, 2, 23, 59)
+ * )
+ * //=> 1
+ */
+export function differenceInCalendarDays(laterDate, earlierDate, options) {
+  const [laterDate_, earlierDate_] = normalizeDates(
+    options?.in,
+    laterDate,
+    earlierDate,
+  );
+
+  const laterStartOfDay = startOfDay(laterDate_);
+  const earlierStartOfDay = startOfDay(earlierDate_);
+
+  const laterTimestamp =
+    +laterStartOfDay - getTimezoneOffsetInMilliseconds(laterStartOfDay);
+  const earlierTimestamp =
+    +earlierStartOfDay - getTimezoneOffsetInMilliseconds(earlierStartOfDay);
+
+  // Round the number of days to the nearest integer because the number of
+  // milliseconds in a day is not constant (e.g. it's different in the week of
+  // the daylight saving time clock shift).
+  return Math.round((laterTimestamp - earlierTimestamp) / millisecondsInDay);
+}
+
+// Fallback for modularized imports:
+export default differenceInCalendarDays;