DMleadgen
46d973904b
Next.js website for Rocky Mountain Vending company featuring: - Product catalog with Stripe integration - Service areas and parts pages - Admin dashboard with Clerk authentication - SEO optimized pages with JSON-LD structured data Co-authored-by: Cursor <cursoragent@cursor.com>
63 lines
2.1 KiB
Text
63 lines
2.1 KiB
Text
import { normalizeDates } from "./_lib/normalizeDates.js";
|
|
import { compareAsc } from "./compareAsc.js";
|
|
import { differenceInCalendarYears } from "./differenceInCalendarYears.js";
|
|
|
|
/**
|
|
* The {@link differenceInYears} function options.
|
|
*/
|
|
|
|
/**
|
|
* @name differenceInYears
|
|
* @category Year Helpers
|
|
* @summary Get the number of full years between the given dates.
|
|
*
|
|
* @description
|
|
* Get the number of full years between the given dates.
|
|
*
|
|
* @param laterDate - The later date
|
|
* @param earlierDate - The earlier date
|
|
* @param options - An object with options
|
|
*
|
|
* @returns The number of full years
|
|
*
|
|
* @example
|
|
* // How many full years are between 31 December 2013 and 11 February 2015?
|
|
* const result = differenceInYears(new Date(2015, 1, 11), new Date(2013, 11, 31))
|
|
* //=> 1
|
|
*/
|
|
export function differenceInYears(laterDate, earlierDate, options) {
|
|
const [laterDate_, earlierDate_] = normalizeDates(
|
|
options?.in,
|
|
laterDate,
|
|
earlierDate,
|
|
);
|
|
|
|
// -1 if the left date is earlier than the right date
|
|
// 2023-12-31 - 2024-01-01 = -1
|
|
const sign = compareAsc(laterDate_, earlierDate_);
|
|
|
|
// First calculate the difference in calendar years
|
|
// 2024-01-01 - 2023-12-31 = 1 year
|
|
const diff = Math.abs(differenceInCalendarYears(laterDate_, earlierDate_));
|
|
|
|
// Now we need to calculate if the difference is full. To do that we set
|
|
// both dates to the same year and check if the both date's month and day
|
|
// form a full year.
|
|
laterDate_.setFullYear(1584);
|
|
earlierDate_.setFullYear(1584);
|
|
|
|
// For it to be true, when the later date is indeed later than the earlier date
|
|
// (2026-02-01 - 2023-12-10 = 3 years), the difference is full if
|
|
// the normalized later date is also later than the normalized earlier date.
|
|
// In our example, 1584-02-01 is earlier than 1584-12-10, so the difference
|
|
// is partial, hence we need to subtract 1 from the difference 3 - 1 = 2.
|
|
const partial = compareAsc(laterDate_, earlierDate_) === -sign;
|
|
|
|
const result = sign * (diff - +partial);
|
|
|
|
// Prevent negative zero
|
|
return result === 0 ? 0 : result;
|
|
}
|
|
|
|
// Fallback for modularized imports:
|
|
export default differenceInYears;
|