index.js 1.0 KB

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  1. import toDate from "../toDate/index.js";
  2. import requiredArgs from "../_lib/requiredArgs/index.js";
  3. /**
  4. * @name startOfYear
  5. * @category Year Helpers
  6. * @summary Return the start of a year for the given date.
  7. *
  8. * @description
  9. * Return the start of a year for the given date.
  10. * The result will be in the local timezone.
  11. *
  12. * ### v2.0.0 breaking changes:
  13. *
  14. * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes).
  15. *
  16. * @param {Date|Number} date - the original date
  17. * @returns {Date} the start of a year
  18. * @throws {TypeError} 1 argument required
  19. *
  20. * @example
  21. * // The start of a year for 2 September 2014 11:55:00:
  22. * const result = startOfYear(new Date(2014, 8, 2, 11, 55, 00))
  23. * //=> Wed Jan 01 2014 00:00:00
  24. */
  25. export default function startOfYear(dirtyDate) {
  26. requiredArgs(1, arguments);
  27. var cleanDate = toDate(dirtyDate);
  28. var date = new Date(0);
  29. date.setFullYear(cleanDate.getFullYear(), 0, 1);
  30. date.setHours(0, 0, 0, 0);
  31. return date;
  32. }