vremel/src/datetime/endOfDay.ts

JavaScript date utility library for Temporal API

import { isZonedDateTime } from "../type-utils.js";
import type { Temporal } from "../types.js";
import { endOfTimeForZonedDateTime } from "./_endOfTimeForZonedDateTime.js";

/**
 * Returns the end of a day for the given datetime
 * @param dt datetime object which includes date and time info
 * @returns Temporal object which represents the end of the day
 */
export function endOfDay<
	DateTime extends Temporal.PlainDateTime | Temporal.ZonedDateTime,
>(dt: DateTime): DateTime {
	const withArg = {
		hour: 23,
		minute: 59,
		second: 59,
		millisecond: 999,
		microsecond: 999,
		nanosecond: 999,
	};
	if (!isZonedDateTime(dt)) {
		return dt.with(withArg) as DateTime;
	}
	return endOfTimeForZonedDateTime(dt, withArg) as DateTime;
}