bluebird的promiseall浅析

Promise.all

hexo中load方法使用了Promise.all,来看代码：

Hexo.prototype.load = function(callback){
  var self = this;

  return loadDatabase(this).then(function(){
    return Promise.all([
      self.source.process(),
      self.theme.process()
    ]);
  }).then(function(){
    return self._generate({cache: true});
    //只有当上面两个方法都执行成功后才会调用_
  }).nodeify(callback);
};

var Promise = require('bluebird');

var call = function(name, args, callback){
  if (!callback && typeof args === 'function'){
    callback = args;
    args = {};
  }

  return Promise.all([
      (function(){
         console.log('1');//这里会打印
         //var i = '5';
      })(),
      (function(){
         //console.log('2');//这里不会打印

         throw '2';
      })(),
      (function(){
         console.log('6');//这里不会打印
      })()
    ]).then(function(){//数组里的都通过才会打印3
    console.log('3');
  }).nodeify(callback);
};

 call('new', '2',function(e){
  console.log('nodeify');
 	console.log(e);
 	console.log('callback'); //进入reject会调用callback

  //throw ;
 }).then(function() {
      	console.log('then');
    }).catch(function(err) {
      console.log('end');
      console.log(err);//进入reject会调用
 });