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/*
==================================================================================================
Core - JavaScript Foundation
Copyright 2013-2014 Sebastian Fastner
==================================================================================================
*/
/**
* Promises implementation of A+ specification passing Promises/A+ test suite.
* http://promises-aplus.github.com/promises-spec/
*
* Based upon Native Promise Only
* v0.7.8-a (c) Kyle Simpson
* MIT License: http://getify.mit-license.org
*/
(function() {
/*jshint validthis:true */
"use strict";
var builtInProp, cycle, scheduling_queue,
ToString = Object.prototype.toString,
timer = (typeof setImmediate != "undefined") ?
function timer(fn) { return setImmediate(fn); } :
setTimeout
;
// dammit, IE8.
try {
Object.defineProperty({},"x",{});
builtInProp = function builtInProp(obj,name,val,config) {
return Object.defineProperty(obj,name,{
value: val,
writable: true,
configurable: config !== false
});
};
}
catch (err) {
builtInProp = function builtInProp(obj,name,val) {
obj[name] = val;
return obj;
};
}
// Note: using a queue instead of array for efficiency
scheduling_queue = (function Queue() {
var first, last, item;
function Item(fn,self) {
this.fn = fn;
this.self = self;
this.next = void 0;
}
return {
add: function add(fn,self) {
item = new Item(fn,self);
if (last) {
last.next = item;
}
else {
first = item;
}
last = item;
item = void 0;
},
drain: function drain() {
var f = first;
first = last = cycle = void 0;
while (f) {
f.fn.call(f.self);
f = f.next;
}
}
};
})();
function schedule(fn,self) {
scheduling_queue.add(fn,self);
if (!cycle) {
cycle = timer(scheduling_queue.drain);
}
}
// promise duck typing
function isThenable(o) {
var _then, o_type = typeof o;
if (o != null &&
(
o_type == "object" || o_type == "function"
)
) {
_then = o.then;
}
return typeof _then == "function" ? _then : false;
}
function notify() {
for (var i=0; i<this.chain.length; i++) {
notifyIsolated(
this,
(this.state === 1) ? this.chain[i].success : this.chain[i].failure,
this.chain[i]
);
}
this.chain.length = 0;
}
// NOTE: This is a separate function to isolate
// the `try..catch` so that other code can be
// optimized better
function notifyIsolated(self,cb,chain) {
var ret, _then;
try {
if (cb === false) {
chain.reject(self.msg);
}
else {
if (cb === true) {
ret = self.msg;
}
else {
ret = cb.call(void 0,self.msg);
}
if (ret === chain.promise) {
chain.reject(TypeError("Promise-chain cycle"));
}
else if (_then = isThenable(ret)) {
_then.call(ret,chain.resolve,chain.reject);
}
else {
chain.resolve(ret);
}
}
}
catch (err) {
chain.reject(err);
}
}
function resolve(msg) {
var _then, def_wrapper, self = this;
// already triggered?
if (self.triggered) { return; }
self.triggered = true;
// unwrap
if (self.def) {
self = self.def;
}
try {
if (_then = isThenable(msg)) {
def_wrapper = new MakeDefWrapper(self);
_then.call(msg,
function $resolve$(){ resolve.apply(def_wrapper,arguments); },
function $reject$(){ reject.apply(def_wrapper,arguments); }
);
}
else {
self.msg = msg;
self.state = 1;
if (self.chain.length > 0) {
schedule(notify,self);
}
}
}
catch (err) {
reject.call(def_wrapper || (new MakeDefWrapper(self)),err);
}
}
function reject(msg) {
var self = this;
// already triggered?
if (self.triggered) { return; }
self.triggered = true;
// unwrap
if (self.def) {
self = self.def;
}
self.msg = msg;
self.state = 2;
if (self.chain.length > 0) {
schedule(notify,self);
}
}
function iteratePromises(Constructor,arr,resolver,rejecter) {
for (var idx=0; idx<arr.length; idx++) {
(function IIFE(idx){
Constructor.resolve(arr[idx])
.then(
function $resolver$(msg){
resolver(idx,msg);
},
rejecter
);
})(idx);
}
}
function MakeDefWrapper(self) {
this.def = self;
this.triggered = false;
}
function MakeDef(self) {
this.promise = self;
this.state = 0;
this.triggered = false;
this.chain = [];
this.msg = void 0;
}
function Promise(executor, context) {
if (typeof executor != "function") {
throw TypeError("Not a function");
}
if (this.__NPO__ !== 0) {
throw TypeError("Not a promise");
}
// instance shadowing the inherited "brand"
// to signal an already "initialized" promise
this.__NPO__ = 1;
var def = new MakeDef(this);
this["then"] = function then(success,failure,context) {
if (context) {
if (typeof(success) == "function") {
success = success.bind(context);
}
if (typeof(failure) == "function") {
failure = failure.bind(context);
}
}
var o = {
success: typeof success == "function" ? success : true,
failure: typeof failure == "function" ? failure : false
};
// Note: `then(..)` itself can be borrowed to be used against
// a different promise constructor for making the chained promise,
// by substituting a different `this` binding.
o.promise = new this.constructor(function extractChain(resolve,reject) {
if (typeof resolve != "function" || typeof reject != "function") {
throw TypeError("Not a function");
}
o.resolve = resolve;
o.reject = reject;
});
def.chain.push(o);
if (def.state !== 0) {
schedule(notify,def);
}
return o.promise;
};
this["catch"] = function $catch$(failure) {
return this.then(void 0,failure);
};
this["done"] = function done(){
return this.then(void 0, function(reason) {
if (jasy.Env.isSet("debug"))
{
console.error("Promise rejected: ", reason);
}
throw reason;
});
};
try {
if (context === undefined) {
context = void 0;
}
executor.call(
context,
function publicResolve(msg){
resolve.call(def,msg);
},
function publicReject(msg) {
reject.call(def,msg);
}
);
}
catch (err) {
reject.call(def,err);
}
}
var PromisePrototype = builtInProp({},"constructor",Promise,
/*configurable=*/false
);
// Note: Android 4 cannot use `Object.defineProperty(..)` here
Promise.prototype = PromisePrototype;
// built-in "brand" to signal an "uninitialized" promise
builtInProp(PromisePrototype,"__NPO__",0,
/*configurable=*/false
);
builtInProp(Promise,"resolve",function Promise$resolve(msg) {
var Constructor = this;
// spec mandated checks
// note: best "isPromise" check that's practical for now
if (msg && typeof msg == "object" && msg.__NPO__ === 1) {
return msg;
}
return new Constructor(function executor(resolve,reject){
if (typeof resolve != "function" || typeof reject != "function") {
throw TypeError("Not a function");
}
resolve(msg);
});
});
builtInProp(Promise,"reject",function Promise$reject(msg) {
return new this(function executor(resolve,reject){
if (typeof resolve != "function" || typeof reject != "function") {
throw TypeError("Not a function");
}
reject(msg);
});
});
builtInProp(Promise,"all",function Promise$all(arr) {
var Constructor = this;
// spec mandated checks
if (ToString.call(arr) != "[object Array]") {
return Constructor.reject(TypeError("Not an array"));
}
if (arr.length === 0) {
return Constructor.resolve([]);
}
return new Constructor(function executor(resolve,reject){
if (typeof resolve != "function" || typeof reject != "function") {
throw TypeError("Not a function");
}
var len = arr.length, msgs = Array(len), count = 0;
iteratePromises(Constructor,arr,function resolver(idx,msg) {
msgs[idx] = msg;
if (++count === len) {
resolve(msgs);
}
},reject);
});
});
builtInProp(Promise,"race",function Promise$race(arr) {
var Constructor = this;
// spec mandated checks
if (ToString.call(arr) != "[object Array]") {
return Constructor.reject(TypeError("Not an array"));
}
return new Constructor(function executor(resolve,reject){
if (typeof resolve != "function" || typeof reject != "function") {
throw TypeError("Not a function");
}
iteratePromises(Constructor,arr,function resolver(idx,msg){
resolve(msg);
},reject);
});
});
core.Main.declareNamespace("core.event.Promise", Promise);
})();