dojo/promise/all.js

Dojo core is a powerful, lightweight library that makes common tasks quicker and easier. Animate elements, manipulate the DOM, and query with easy CSS syntax, all without sacrificing performance.

define([
	"../_base/array",
	"../_base/lang",
	"../Deferred",
	"../when"
], function(array, lang, Deferred, when){
	"use strict";

	// module:
	//		dojo/promise/all

	var some = array.some;

	return function all(objectOrArray){
		// summary:
		//		Takes multiple promises and returns a new promise that is fulfilled
		//		when all promises have been resolved or one has been rejected.
		// description:
		//		Takes multiple promises and returns a new promise that is fulfilled
		//		when all promises have been resolved or one has been rejected. If one of
		//		the promises is rejected, the returned promise is also rejected. Canceling
		//		the returned promise will *not* cancel any passed promises.
		// objectOrArray: Object|Array?
		//		The promise will be fulfilled with a list of results if invoked with an
		//		array, or an object of results when passed an object (using the same
		//		keys). If passed neither an object or array it is resolved with an
		//		undefined value.
		// returns: dojo/promise/Promise

		var object, array;
		if(lang.isArray(objectOrArray)){
			array = objectOrArray;
		}else if(objectOrArray && typeof objectOrArray === "object"){
			object = objectOrArray;
		}

		var results;
		var keyLookup = [];
		if(object){
			array = [];
			for(var key in object){
				if(Object.hasOwnProperty.call(object, key)){
					keyLookup.push(key);
					array.push(object[key]);
				}
			}
			results = {};
		}else if(array){
			results = [];
		}

		if(!array || !array.length){
			return new Deferred().resolve(results);
		}

		var deferred = new Deferred();
		deferred.promise.always(function(){
			results = keyLookup = null;
		});
		var waiting = array.length;
		some(array, function(valueOrPromise, index){
			if(!object){
				keyLookup.push(index);
			}
			when(valueOrPromise, function(value){
				if(!deferred.isFulfilled()){
					results[keyLookup[index]] = value;
					if(--waiting === 0){
						deferred.resolve(results);
					}
				}
			}, deferred.reject);
			return deferred.isFulfilled();
		});
		return deferred.promise;	// dojo/promise/Promise
	};
});