1(function (global) { 2 3 // 4 // Check for native Promise and it has correct interface 5 // 6 7 var NativePromise = global['Promise']; 8 var nativePromiseSupported = 9 NativePromise && 10 // Some of these methods are missing from 11 // Firefox/Chrome experimental implementations 12 'resolve' in NativePromise && 13 'reject' in NativePromise && 14 'all' in NativePromise && 15 'race' in NativePromise && 16 // Older version of the spec had a resolver object 17 // as the arg rather than a function 18 (function () { 19 var resolve; 20 new NativePromise(function (r) { resolve = r; }); 21 return typeof resolve === 'function'; 22 })(); 23 24 25 // 26 // export if necessary 27 // 28 29 if (typeof exports !== 'undefined' && exports) { 30 // node.js 31 exports.Promise = nativePromiseSupported ? NativePromise : Promise; 32 exports.Polyfill = Promise; 33 } 34 else { 35 // AMD 36 if (typeof define == 'function' && define.amd) { 37 define(function () { 38 return nativePromiseSupported ? NativePromise : Promise; 39 }); 40 } 41 else { 42 // in browser add to global 43 if (!nativePromiseSupported) 44 global['Promise'] = Promise; 45 } 46 } 47 48 49 // 50 // Polyfill 51 // 52 53 var PENDING = 'pending'; 54 var SEALED = 'sealed'; 55 var FULFILLED = 'fulfilled'; 56 var REJECTED = 'rejected'; 57 var NOOP = function () { }; 58 59 function isArray(value) { 60 return Object.prototype.toString.call(value) === '[object Array]'; 61 } 62 63 // async calls 64 var asyncSetTimer = typeof setImmediate !== 'undefined' ? setImmediate : setTimeout; 65 var asyncQueue = []; 66 var asyncTimer; 67 68 function asyncFlush() { 69 // run promise callbacks 70 for (var i = 0; i < asyncQueue.length; i++) 71 asyncQueue[i][0](asyncQueue[i][1]); 72 73 // reset async asyncQueue 74 asyncQueue = []; 75 asyncTimer = false; 76 // print("asyncFlush"); 77 } 78 79 function asyncCall(callback, arg) { 80 asyncQueue.push([callback, arg]); 81 82 if (!asyncTimer) { 83 asyncTimer = true; 84 asyncSetTimer(asyncFlush, 1); 85 } 86 } 87 88 89 function invokeResolver(resolver, promise) { 90 function resolvePromise(value) { 91 resolve(promise, value); 92 } 93 94 function rejectPromise(reason) { 95 reject(promise, reason); 96 } 97 98 try { 99 resolver(resolvePromise, rejectPromise); 100 } catch (e) { 101 rejectPromise(e); 102 } 103 } 104 105 function invokeCallback(subscriber) { 106 var owner = subscriber.owner; 107 var settled = owner.state_; 108 var value = owner.data_; 109 var callback = subscriber[settled]; 110 var promise = subscriber.then; 111 112 if (typeof callback === 'function') { 113 settled = FULFILLED; 114 try { 115 value = callback(value); 116 } catch (e) { 117 reject(promise, e); 118 } 119 } 120 121 if (!handleThenable(promise, value)) { 122 if (settled === FULFILLED) 123 resolve(promise, value); 124 125 if (settled === REJECTED) 126 reject(promise, value); 127 } 128 } 129 130 function handleThenable(promise, value) { 131 var resolved; 132 133 try { 134 if (promise === value) 135 throw new TypeError('A promises callback cannot return that same promise.'); 136 137 if (value && (typeof value === 'function' || typeof value === 'object')) { 138 var then = value.then; // then should be retrived only once 139 140 if (typeof then === 'function') { 141 then.call(value, function (val) { 142 if (!resolved) { 143 resolved = true; 144 145 if (value !== val) 146 resolve(promise, val); 147 else 148 fulfill(promise, val); 149 } 150 }, function (reason) { 151 if (!resolved) { 152 resolved = true; 153 154 reject(promise, reason); 155 } 156 }); 157 158 return true; 159 } 160 } 161 } catch (e) { 162 if (!resolved) 163 reject(promise, e); 164 165 return true; 166 } 167 168 return false; 169 } 170 171 function resolve(promise, value) { 172 if (promise === value || !handleThenable(promise, value)) 173 fulfill(promise, value); 174 } 175 176 function fulfill(promise, value) { 177 if (promise.state_ === PENDING) { 178 promise.state_ = SEALED; 179 promise.data_ = value; 180 181 asyncCall(publishFulfillment, promise); 182 } 183 } 184 185 function reject(promise, reason) { 186 if (promise.state_ === PENDING) { 187 promise.state_ = SEALED; 188 promise.data_ = reason; 189 190 asyncCall(publishRejection, promise); 191 } 192 } 193 194 function publish(promise) { 195 var callbacks = promise.then_; 196 promise.then_ = undefined; 197 198 for (var i = 0; i < callbacks.length; i++) { 199 invokeCallback(callbacks[i]); 200 } 201 } 202 203 function publishFulfillment(promise) { 204 promise.state_ = FULFILLED; 205 publish(promise); 206 } 207 208 function publishRejection(promise) { 209 promise.state_ = REJECTED; 210 publish(promise); 211 } 212 213 /** 214 * @class 215 */ 216 function Promise(resolver) { 217 if (typeof resolver !== 'function') 218 throw new TypeError('Promise constructor takes a function argument'); 219 220 if (this instanceof Promise === false) 221 throw new TypeError('Failed to construct \'Promise\': Please use the \'new\' operator, this object constructor cannot be called as a function.'); 222 223 this.then_ = []; 224 225 invokeResolver(resolver, this); 226 } 227 228 Promise.prototype = { 229 constructor: Promise, 230 231 state_: PENDING, 232 then_: null, 233 data_: undefined, 234 235 then: function (onFulfillment, onRejection) { 236 var subscriber = { 237 owner: this, 238 then: new this.constructor(NOOP), 239 fulfilled: onFulfillment, 240 rejected: onRejection 241 }; 242 243 if (this.state_ === FULFILLED || this.state_ === REJECTED) { 244 // already resolved, call callback async 245 asyncCall(invokeCallback, subscriber); 246 } 247 else { 248 // subscribe 249 this.then_.push(subscriber); 250 } 251 252 return subscriber.then; 253 }, 254 255 'catch': function (onRejection) { 256 return this.then(null, onRejection); 257 } 258 }; 259 260 Promise.all = function (promises) { 261 var Class = this; 262 263 if (!isArray(promises)) 264 throw new TypeError('You must pass an array to Promise.all().'); 265 266 return new Class(function (resolve, reject) { 267 var results = []; 268 var remaining = 0; 269 270 function resolver(index) { 271 remaining++; 272 return function (value) { 273 results[index] = value; 274 if (!--remaining) 275 resolve(results); 276 }; 277 } 278 279 for (var i = 0, promise; i < promises.length; i++) { 280 promise = promises[i]; 281 282 if (promise && typeof promise.then === 'function') 283 promise.then(resolver(i), reject); 284 else 285 results[i] = promise; 286 } 287 288 if (!remaining) 289 resolve(results); 290 }); 291 }; 292 293 Promise.race = function (promises) { 294 var Class = this; 295 296 if (!isArray(promises)) 297 throw new TypeError('You must pass an array to Promise.race().'); 298 299 return new Class(function (resolve, reject) { 300 for (var i = 0, promise; i < promises.length; i++) { 301 promise = promises[i]; 302 303 if (promise && typeof promise.then === 'function') 304 promise.then(resolve, reject); 305 else 306 resolve(promise); 307 } 308 }); 309 }; 310 311 Promise.resolve = function (value) { 312 var Class = this; 313 314 if (value && typeof value === 'object' && value.constructor === Class) 315 return value; 316 317 return new Class(function (resolve) { 318 resolve(value); 319 }); 320 }; 321 322 Promise.reject = function (reason) { 323 var Class = this; 324 325 return new Class(function (resolve, reject) { 326 reject(reason); 327 }); 328 }; 329 330})(typeof window != 'undefined' ? window : typeof global != 'undefined' ? global : typeof self != 'undefined' ? self : this);