使差值`w-v`为正的`v`的最小日期

function findMinDate(w, v) {
  const oneDay = 24 * 60 * 60 * 1000; // 一天的毫秒数
  let currentDate = new Date(v); // 将字符串日期转换为Date对象
  const targetDate = new Date(w); // 将字符串日期转换为Date对象
  let minDate = null;

  while (currentDate <= targetDate) {
    const diff = targetDate.getTime() - currentDate.getTime();
    if (diff > 0) {
      minDate = currentDate;
      break;
    }
    currentDate = new Date(currentDate.getTime() + oneDay); // 增加一天
  }

  return minDate ? minDate.toISOString().split('T')[0] : null; // 返回最小日期的字符串表示形式
}

const w = '2022-01-01';
const v = '2021-12-30';
const minDate = findMinDate(w, v);
console.log(minDate); // 输出：2021-12-30