1. bluebird
如果第三方的那些函数库是符合错误优化的规则的话,可以直接用 bluebird 批量转换
1.1. 注意
As a notable exception in fs, fs.existsAsync doesn't work as expected, because Node's fs.exists doesn't call back with error as first argument. More at #418. One possible workaround is using fs.statAsync.
翻译
必须回调函数第一个参数是 error