36 lines
1.2 KiB
JavaScript
36 lines
1.2 KiB
JavaScript
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import { toDate } from "./toDate.mjs";
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/**
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* @name lastDayOfDecade
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* @category Decade Helpers
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* @summary Return the last day of a decade for the given date.
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*
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* @description
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* Return the last day of a decade for the given date.
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*
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* @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).
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*
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* @param date - The original date
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*
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* @returns The last day of a decade
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*
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* @example
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* // The last day of a decade for 21 December 2012 21:12:00:
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* const result = lastDayOfDecade(new Date(2012, 11, 21, 21, 12, 00))
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* //=> Wed Dec 31 2019 00:00:00
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*/
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export function lastDayOfDecade(date) {
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// TODO: Switch to more technical definition in of decades that start with 1
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// end with 0. I.e. 2001-2010 instead of current 2000-2009. It's a breaking
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// change, so it can only be done in 4.0.
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const _date = toDate(date);
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const year = _date.getFullYear();
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const decade = 9 + Math.floor(year / 10) * 10;
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_date.setFullYear(decade + 1, 0, 0);
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_date.setHours(0, 0, 0, 0);
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return _date;
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}
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// Fallback for modularized imports:
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export default lastDayOfDecade;
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