滚动时间设置为0无效

源码中有这么一段
$.scrollTo = function(scrollTop, duration, callback) {
duration = duration || 1000;
var scroll = function(duration) {
if (duration <= 0) {
window.scrollTo(0, scrollTop);
callback && callback();
return;
}
var distaince = scrollTop - window.scrollY;
setTimeout(function() {
window.scrollTo(0, window.scrollY + distaince / duration * 10);
scroll(duration - 10);
}, 16.7);
};
scroll(duration);
};
但是 0||1000 只能是1000不会是0 所以设置为0毫无效果