/**
 * @name startOfYesterday
 * @category Day Helpers
 * @summary Return the start of yesterday.
 * @pure false
 *
 * @description
 * Return the start of yesterday.
 *
 * > ⚠️ Please note that this function is not present in the FP submodule as
 * > it uses `new Date()` internally hence impure and can't be safely curried.
 *
 * @returns {Date} the start of yesterday
 *
 * @example
 * // If today is 6 October 2014:
 * const result = startOfYesterday()
 * //=> Sun Oct 5 2014 00:00:00
 */
export default function startOfYesterday(): Date {
  const now = new Date()
  const year = now.getFullYear()
  const month = now.getMonth()
  const day = now.getDate()

  const date = new Date(0)
  date.setFullYear(year, month, day - 1)
  date.setHours(0, 0, 0, 0)
  return date
}