ncase.me-trust/js/lib/q.js

2077 lines
62 KiB
JavaScript
Raw Normal View History

2017-06-20 11:10:41 +00:00
// vim:ts=4:sts=4:sw=4:
/*!
*
* Copyright 2009-2017 Kris Kowal under the terms of the MIT
* license found at https://github.com/kriskowal/q/blob/v1/LICENSE
*
* With parts by Tyler Close
* Copyright 2007-2009 Tyler Close under the terms of the MIT X license found
* at http://www.opensource.org/licenses/mit-license.html
* Forked at ref_send.js version: 2009-05-11
*
* With parts by Mark Miller
* Copyright (C) 2011 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
(function (definition) {
"use strict";
// This file will function properly as a <script> tag, or a module
// using CommonJS and NodeJS or RequireJS module formats. In
// Common/Node/RequireJS, the module exports the Q API and when
// executed as a simple <script>, it creates a Q global instead.
// Montage Require
if (typeof bootstrap === "function") {
bootstrap("promise", definition);
// CommonJS
} else if (typeof exports === "object" && typeof module === "object") {
module.exports = definition();
// RequireJS
} else if (typeof define === "function" && define.amd) {
define(definition);
// SES (Secure EcmaScript)
} else if (typeof ses !== "undefined") {
if (!ses.ok()) {
return;
} else {
ses.makeQ = definition;
}
// <script>
} else if (typeof window !== "undefined" || typeof self !== "undefined") {
// Prefer window over self for add-on scripts. Use self for
// non-windowed contexts.
var global = typeof window !== "undefined" ? window : self;
// Get the `window` object, save the previous Q global
// and initialize Q as a global.
var previousQ = global.Q;
global.Q = definition();
// Add a noConflict function so Q can be removed from the
// global namespace.
global.Q.noConflict = function () {
global.Q = previousQ;
return this;
};
} else {
throw new Error("This environment was not anticipated by Q. Please file a bug.");
}
})(function () {
"use strict";
var hasStacks = false;
try {
throw new Error();
} catch (e) {
hasStacks = !!e.stack;
}
// All code after this point will be filtered from stack traces reported
// by Q.
var qStartingLine = captureLine();
var qFileName;
// shims
// used for fallback in "allResolved"
var noop = function () {};
// Use the fastest possible means to execute a task in a future turn
// of the event loop.
var nextTick =(function () {
// linked list of tasks (single, with head node)
var head = {task: void 0, next: null};
var tail = head;
var flushing = false;
var requestTick = void 0;
var isNodeJS = false;
// queue for late tasks, used by unhandled rejection tracking
var laterQueue = [];
function flush() {
/* jshint loopfunc: true */
var task, domain;
while (head.next) {
head = head.next;
task = head.task;
head.task = void 0;
domain = head.domain;
if (domain) {
head.domain = void 0;
domain.enter();
}
runSingle(task, domain);
}
while (laterQueue.length) {
task = laterQueue.pop();
runSingle(task);
}
flushing = false;
}
// runs a single function in the async queue
function runSingle(task, domain) {
try {
task();
} catch (e) {
if (isNodeJS) {
// In node, uncaught exceptions are considered fatal errors.
// Re-throw them synchronously to interrupt flushing!
// Ensure continuation if the uncaught exception is suppressed
// listening "uncaughtException" events (as domains does).
// Continue in next event to avoid tick recursion.
if (domain) {
domain.exit();
}
setTimeout(flush, 0);
if (domain) {
domain.enter();
}
throw e;
} else {
// In browsers, uncaught exceptions are not fatal.
// Re-throw them asynchronously to avoid slow-downs.
setTimeout(function () {
throw e;
}, 0);
}
}
if (domain) {
domain.exit();
}
}
nextTick = function (task) {
tail = tail.next = {
task: task,
domain: isNodeJS && process.domain,
next: null
};
if (!flushing) {
flushing = true;
requestTick();
}
};
if (typeof process === "object" &&
process.toString() === "[object process]" && process.nextTick) {
// Ensure Q is in a real Node environment, with a `process.nextTick`.
// To see through fake Node environments:
// * Mocha test runner - exposes a `process` global without a `nextTick`
// * Browserify - exposes a `process.nexTick` function that uses
// `setTimeout`. In this case `setImmediate` is preferred because
// it is faster. Browserify's `process.toString()` yields
// "[object Object]", while in a real Node environment
// `process.toString()` yields "[object process]".
isNodeJS = true;
requestTick = function () {
process.nextTick(flush);
};
} else if (typeof setImmediate === "function") {
// In IE10, Node.js 0.9+, or https://github.com/NobleJS/setImmediate
if (typeof window !== "undefined") {
requestTick = setImmediate.bind(window, flush);
} else {
requestTick = function () {
setImmediate(flush);
};
}
} else if (typeof MessageChannel !== "undefined") {
// modern browsers
// http://www.nonblocking.io/2011/06/windownexttick.html
var channel = new MessageChannel();
// At least Safari Version 6.0.5 (8536.30.1) intermittently cannot create
// working message ports the first time a page loads.
channel.port1.onmessage = function () {
requestTick = requestPortTick;
channel.port1.onmessage = flush;
flush();
};
var requestPortTick = function () {
// Opera requires us to provide a message payload, regardless of
// whether we use it.
channel.port2.postMessage(0);
};
requestTick = function () {
setTimeout(flush, 0);
requestPortTick();
};
} else {
// old browsers
requestTick = function () {
setTimeout(flush, 0);
};
}
// runs a task after all other tasks have been run
// this is useful for unhandled rejection tracking that needs to happen
// after all `then`d tasks have been run.
nextTick.runAfter = function (task) {
laterQueue.push(task);
if (!flushing) {
flushing = true;
requestTick();
}
};
return nextTick;
})();
// Attempt to make generics safe in the face of downstream
// modifications.
// There is no situation where this is necessary.
// If you need a security guarantee, these primordials need to be
// deeply frozen anyway, and if you dont need a security guarantee,
// this is just plain paranoid.
// However, this **might** have the nice side-effect of reducing the size of
// the minified code by reducing x.call() to merely x()
// See Mark Millers explanation of what this does.
// http://wiki.ecmascript.org/doku.php?id=conventions:safe_meta_programming
var call = Function.call;
function uncurryThis(f) {
return function () {
return call.apply(f, arguments);
};
}
// This is equivalent, but slower:
// uncurryThis = Function_bind.bind(Function_bind.call);
// http://jsperf.com/uncurrythis
var array_slice = uncurryThis(Array.prototype.slice);
var array_reduce = uncurryThis(
Array.prototype.reduce || function (callback, basis) {
var index = 0,
length = this.length;
// concerning the initial value, if one is not provided
if (arguments.length === 1) {
// seek to the first value in the array, accounting
// for the possibility that is is a sparse array
do {
if (index in this) {
basis = this[index++];
break;
}
if (++index >= length) {
throw new TypeError();
}
} while (1);
}
// reduce
for (; index < length; index++) {
// account for the possibility that the array is sparse
if (index in this) {
basis = callback(basis, this[index], index);
}
}
return basis;
}
);
var array_indexOf = uncurryThis(
Array.prototype.indexOf || function (value) {
// not a very good shim, but good enough for our one use of it
for (var i = 0; i < this.length; i++) {
if (this[i] === value) {
return i;
}
}
return -1;
}
);
var array_map = uncurryThis(
Array.prototype.map || function (callback, thisp) {
var self = this;
var collect = [];
array_reduce(self, function (undefined, value, index) {
collect.push(callback.call(thisp, value, index, self));
}, void 0);
return collect;
}
);
var object_create = Object.create || function (prototype) {
function Type() { }
Type.prototype = prototype;
return new Type();
};
var object_defineProperty = Object.defineProperty || function (obj, prop, descriptor) {
obj[prop] = descriptor.value;
return obj;
};
var object_hasOwnProperty = uncurryThis(Object.prototype.hasOwnProperty);
var object_keys = Object.keys || function (object) {
var keys = [];
for (var key in object) {
if (object_hasOwnProperty(object, key)) {
keys.push(key);
}
}
return keys;
};
var object_toString = uncurryThis(Object.prototype.toString);
function isObject(value) {
return value === Object(value);
}
// generator related shims
// FIXME: Remove this function once ES6 generators are in SpiderMonkey.
function isStopIteration(exception) {
return (
object_toString(exception) === "[object StopIteration]" ||
exception instanceof QReturnValue
);
}
// FIXME: Remove this helper and Q.return once ES6 generators are in
// SpiderMonkey.
var QReturnValue;
if (typeof ReturnValue !== "undefined") {
QReturnValue = ReturnValue;
} else {
QReturnValue = function (value) {
this.value = value;
};
}
// long stack traces
var STACK_JUMP_SEPARATOR = "From previous event:";
function makeStackTraceLong(error, promise) {
// If possible, transform the error stack trace by removing Node and Q
// cruft, then concatenating with the stack trace of `promise`. See #57.
if (hasStacks &&
promise.stack &&
typeof error === "object" &&
error !== null &&
error.stack
) {
var stacks = [];
for (var p = promise; !!p; p = p.source) {
if (p.stack && (!error.__minimumStackCounter__ || error.__minimumStackCounter__ > p.stackCounter)) {
object_defineProperty(error, "__minimumStackCounter__", {value: p.stackCounter, configurable: true});
stacks.unshift(p.stack);
}
}
stacks.unshift(error.stack);
var concatedStacks = stacks.join("\n" + STACK_JUMP_SEPARATOR + "\n");
var stack = filterStackString(concatedStacks);
object_defineProperty(error, "stack", {value: stack, configurable: true});
}
}
function filterStackString(stackString) {
var lines = stackString.split("\n");
var desiredLines = [];
for (var i = 0; i < lines.length; ++i) {
var line = lines[i];
if (!isInternalFrame(line) && !isNodeFrame(line) && line) {
desiredLines.push(line);
}
}
return desiredLines.join("\n");
}
function isNodeFrame(stackLine) {
return stackLine.indexOf("(module.js:") !== -1 ||
stackLine.indexOf("(node.js:") !== -1;
}
function getFileNameAndLineNumber(stackLine) {
// Named functions: "at functionName (filename:lineNumber:columnNumber)"
// In IE10 function name can have spaces ("Anonymous function") O_o
var attempt1 = /at .+ \((.+):(\d+):(?:\d+)\)$/.exec(stackLine);
if (attempt1) {
return [attempt1[1], Number(attempt1[2])];
}
// Anonymous functions: "at filename:lineNumber:columnNumber"
var attempt2 = /at ([^ ]+):(\d+):(?:\d+)$/.exec(stackLine);
if (attempt2) {
return [attempt2[1], Number(attempt2[2])];
}
// Firefox style: "function@filename:lineNumber or @filename:lineNumber"
var attempt3 = /.*@(.+):(\d+)$/.exec(stackLine);
if (attempt3) {
return [attempt3[1], Number(attempt3[2])];
}
}
function isInternalFrame(stackLine) {
var fileNameAndLineNumber = getFileNameAndLineNumber(stackLine);
if (!fileNameAndLineNumber) {
return false;
}
var fileName = fileNameAndLineNumber[0];
var lineNumber = fileNameAndLineNumber[1];
return fileName === qFileName &&
lineNumber >= qStartingLine &&
lineNumber <= qEndingLine;
}
// discover own file name and line number range for filtering stack
// traces
function captureLine() {
if (!hasStacks) {
return;
}
try {
throw new Error();
} catch (e) {
var lines = e.stack.split("\n");
var firstLine = lines[0].indexOf("@") > 0 ? lines[1] : lines[2];
var fileNameAndLineNumber = getFileNameAndLineNumber(firstLine);
if (!fileNameAndLineNumber) {
return;
}
qFileName = fileNameAndLineNumber[0];
return fileNameAndLineNumber[1];
}
}
function deprecate(callback, name, alternative) {
return function () {
if (typeof console !== "undefined" &&
typeof console.warn === "function") {
console.warn(name + " is deprecated, use " + alternative +
" instead.", new Error("").stack);
}
return callback.apply(callback, arguments);
};
}
// end of shims
// beginning of real work
/**
* Constructs a promise for an immediate reference, passes promises through, or
* coerces promises from different systems.
* @param value immediate reference or promise
*/
function Q(value) {
// If the object is already a Promise, return it directly. This enables
// the resolve function to both be used to created references from objects,
// but to tolerably coerce non-promises to promises.
if (value instanceof Promise) {
return value;
}
// assimilate thenables
if (isPromiseAlike(value)) {
return coerce(value);
} else {
return fulfill(value);
}
}
Q.resolve = Q;
/**
* Performs a task in a future turn of the event loop.
* @param {Function} task
*/
Q.nextTick = nextTick;
/**
* Controls whether or not long stack traces will be on
*/
Q.longStackSupport = false;
/**
* The counter is used to determine the stopping point for building
* long stack traces. In makeStackTraceLong we walk backwards through
* the linked list of promises, only stacks which were created before
* the rejection are concatenated.
*/
var longStackCounter = 1;
// enable long stacks if Q_DEBUG is set
if (typeof process === "object" && process && process.env && process.env.Q_DEBUG) {
Q.longStackSupport = true;
}
/**
* Constructs a {promise, resolve, reject} object.
*
* `resolve` is a callback to invoke with a more resolved value for the
* promise. To fulfill the promise, invoke `resolve` with any value that is
* not a thenable. To reject the promise, invoke `resolve` with a rejected
* thenable, or invoke `reject` with the reason directly. To resolve the
* promise to another thenable, thus putting it in the same state, invoke
* `resolve` with that other thenable.
*/
Q.defer = defer;
function defer() {
// if "messages" is an "Array", that indicates that the promise has not yet
// been resolved. If it is "undefined", it has been resolved. Each
// element of the messages array is itself an array of complete arguments to
// forward to the resolved promise. We coerce the resolution value to a
// promise using the `resolve` function because it handles both fully
// non-thenable values and other thenables gracefully.
var messages = [], progressListeners = [], resolvedPromise;
var deferred = object_create(defer.prototype);
var promise = object_create(Promise.prototype);
promise.promiseDispatch = function (resolve, op, operands) {
var args = array_slice(arguments);
if (messages) {
messages.push(args);
if (op === "when" && operands[1]) { // progress operand
progressListeners.push(operands[1]);
}
} else {
Q.nextTick(function () {
resolvedPromise.promiseDispatch.apply(resolvedPromise, args);
});
}
};
// XXX deprecated
promise.valueOf = function () {
if (messages) {
return promise;
}
var nearerValue = nearer(resolvedPromise);
if (isPromise(nearerValue)) {
resolvedPromise = nearerValue; // shorten chain
}
return nearerValue;
};
promise.inspect = function () {
if (!resolvedPromise) {
return { state: "pending" };
}
return resolvedPromise.inspect();
};
if (Q.longStackSupport && hasStacks) {
try {
throw new Error();
} catch (e) {
// NOTE: don't try to use `Error.captureStackTrace` or transfer the
// accessor around; that causes memory leaks as per GH-111. Just
// reify the stack trace as a string ASAP.
//
// At the same time, cut off the first line; it's always just
// "[object Promise]\n", as per the `toString`.
promise.stack = e.stack.substring(e.stack.indexOf("\n") + 1);
promise.stackCounter = longStackCounter++;
}
}
// NOTE: we do the checks for `resolvedPromise` in each method, instead of
// consolidating them into `become`, since otherwise we'd create new
// promises with the lines `become(whatever(value))`. See e.g. GH-252.
function become(newPromise) {
resolvedPromise = newPromise;
if (Q.longStackSupport && hasStacks) {
// Only hold a reference to the new promise if long stacks
// are enabled to reduce memory usage
promise.source = newPromise;
}
array_reduce(messages, function (undefined, message) {
Q.nextTick(function () {
newPromise.promiseDispatch.apply(newPromise, message);
});
}, void 0);
messages = void 0;
progressListeners = void 0;
}
deferred.promise = promise;
deferred.resolve = function (value) {
if (resolvedPromise) {
return;
}
become(Q(value));
};
deferred.fulfill = function (value) {
if (resolvedPromise) {
return;
}
become(fulfill(value));
};
deferred.reject = function (reason) {
if (resolvedPromise) {
return;
}
become(reject(reason));
};
deferred.notify = function (progress) {
if (resolvedPromise) {
return;
}
array_reduce(progressListeners, function (undefined, progressListener) {
Q.nextTick(function () {
progressListener(progress);
});
}, void 0);
};
return deferred;
}
/**
* Creates a Node-style callback that will resolve or reject the deferred
* promise.
* @returns a nodeback
*/
defer.prototype.makeNodeResolver = function () {
var self = this;
return function (error, value) {
if (error) {
self.reject(error);
} else if (arguments.length > 2) {
self.resolve(array_slice(arguments, 1));
} else {
self.resolve(value);
}
};
};
/**
* @param resolver {Function} a function that returns nothing and accepts
* the resolve, reject, and notify functions for a deferred.
* @returns a promise that may be resolved with the given resolve and reject
* functions, or rejected by a thrown exception in resolver
*/
Q.Promise = promise; // ES6
Q.promise = promise;
function promise(resolver) {
if (typeof resolver !== "function") {
throw new TypeError("resolver must be a function.");
}
var deferred = defer();
try {
resolver(deferred.resolve, deferred.reject, deferred.notify);
} catch (reason) {
deferred.reject(reason);
}
return deferred.promise;
}
promise.race = race; // ES6
promise.all = all; // ES6
promise.reject = reject; // ES6
promise.resolve = Q; // ES6
// XXX experimental. This method is a way to denote that a local value is
// serializable and should be immediately dispatched to a remote upon request,
// instead of passing a reference.
Q.passByCopy = function (object) {
//freeze(object);
//passByCopies.set(object, true);
return object;
};
Promise.prototype.passByCopy = function () {
//freeze(object);
//passByCopies.set(object, true);
return this;
};
/**
* If two promises eventually fulfill to the same value, promises that value,
* but otherwise rejects.
* @param x {Any*}
* @param y {Any*}
* @returns {Any*} a promise for x and y if they are the same, but a rejection
* otherwise.
*
*/
Q.join = function (x, y) {
return Q(x).join(y);
};
Promise.prototype.join = function (that) {
return Q([this, that]).spread(function (x, y) {
if (x === y) {
// TODO: "===" should be Object.is or equiv
return x;
} else {
throw new Error("Q can't join: not the same: " + x + " " + y);
}
});
};
/**
* Returns a promise for the first of an array of promises to become settled.
* @param answers {Array[Any*]} promises to race
* @returns {Any*} the first promise to be settled
*/
Q.race = race;
function race(answerPs) {
return promise(function (resolve, reject) {
// Switch to this once we can assume at least ES5
// answerPs.forEach(function (answerP) {
// Q(answerP).then(resolve, reject);
// });
// Use this in the meantime
for (var i = 0, len = answerPs.length; i < len; i++) {
Q(answerPs[i]).then(resolve, reject);
}
});
}
Promise.prototype.race = function () {
return this.then(Q.race);
};
/**
* Constructs a Promise with a promise descriptor object and optional fallback
* function. The descriptor contains methods like when(rejected), get(name),
* set(name, value), post(name, args), and delete(name), which all
* return either a value, a promise for a value, or a rejection. The fallback
* accepts the operation name, a resolver, and any further arguments that would
* have been forwarded to the appropriate method above had a method been
* provided with the proper name. The API makes no guarantees about the nature
* of the returned object, apart from that it is usable whereever promises are
* bought and sold.
*/
Q.makePromise = Promise;
function Promise(descriptor, fallback, inspect) {
if (fallback === void 0) {
fallback = function (op) {
return reject(new Error(
"Promise does not support operation: " + op
));
};
}
if (inspect === void 0) {
inspect = function () {
return {state: "unknown"};
};
}
var promise = object_create(Promise.prototype);
promise.promiseDispatch = function (resolve, op, args) {
var result;
try {
if (descriptor[op]) {
result = descriptor[op].apply(promise, args);
} else {
result = fallback.call(promise, op, args);
}
} catch (exception) {
result = reject(exception);
}
if (resolve) {
resolve(result);
}
};
promise.inspect = inspect;
// XXX deprecated `valueOf` and `exception` support
if (inspect) {
var inspected = inspect();
if (inspected.state === "rejected") {
promise.exception = inspected.reason;
}
promise.valueOf = function () {
var inspected = inspect();
if (inspected.state === "pending" ||
inspected.state === "rejected") {
return promise;
}
return inspected.value;
};
}
return promise;
}
Promise.prototype.toString = function () {
return "[object Promise]";
};
Promise.prototype.then = function (fulfilled, rejected, progressed) {
var self = this;
var deferred = defer();
var done = false; // ensure the untrusted promise makes at most a
// single call to one of the callbacks
function _fulfilled(value) {
try {
return typeof fulfilled === "function" ? fulfilled(value) : value;
} catch (exception) {
return reject(exception);
}
}
function _rejected(exception) {
if (typeof rejected === "function") {
makeStackTraceLong(exception, self);
try {
return rejected(exception);
} catch (newException) {
return reject(newException);
}
}
return reject(exception);
}
function _progressed(value) {
return typeof progressed === "function" ? progressed(value) : value;
}
Q.nextTick(function () {
self.promiseDispatch(function (value) {
if (done) {
return;
}
done = true;
deferred.resolve(_fulfilled(value));
}, "when", [function (exception) {
if (done) {
return;
}
done = true;
deferred.resolve(_rejected(exception));
}]);
});
// Progress propagator need to be attached in the current tick.
self.promiseDispatch(void 0, "when", [void 0, function (value) {
var newValue;
var threw = false;
try {
newValue = _progressed(value);
} catch (e) {
threw = true;
if (Q.onerror) {
Q.onerror(e);
} else {
throw e;
}
}
if (!threw) {
deferred.notify(newValue);
}
}]);
return deferred.promise;
};
Q.tap = function (promise, callback) {
return Q(promise).tap(callback);
};
/**
* Works almost like "finally", but not called for rejections.
* Original resolution value is passed through callback unaffected.
* Callback may return a promise that will be awaited for.
* @param {Function} callback
* @returns {Q.Promise}
* @example
* doSomething()
* .then(...)
* .tap(console.log)
* .then(...);
*/
Promise.prototype.tap = function (callback) {
callback = Q(callback);
return this.then(function (value) {
return callback.fcall(value).thenResolve(value);
});
};
/**
* Registers an observer on a promise.
*
* Guarantees:
*
* 1. that fulfilled and rejected will be called only once.
* 2. that either the fulfilled callback or the rejected callback will be
* called, but not both.
* 3. that fulfilled and rejected will not be called in this turn.
*
* @param value promise or immediate reference to observe
* @param fulfilled function to be called with the fulfilled value
* @param rejected function to be called with the rejection exception
* @param progressed function to be called on any progress notifications
* @return promise for the return value from the invoked callback
*/
Q.when = when;
function when(value, fulfilled, rejected, progressed) {
return Q(value).then(fulfilled, rejected, progressed);
}
Promise.prototype.thenResolve = function (value) {
return this.then(function () { return value; });
};
Q.thenResolve = function (promise, value) {
return Q(promise).thenResolve(value);
};
Promise.prototype.thenReject = function (reason) {
return this.then(function () { throw reason; });
};
Q.thenReject = function (promise, reason) {
return Q(promise).thenReject(reason);
};
/**
* If an object is not a promise, it is as "near" as possible.
* If a promise is rejected, it is as "near" as possible too.
* If its a fulfilled promise, the fulfillment value is nearer.
* If its a deferred promise and the deferred has been resolved, the
* resolution is "nearer".
* @param object
* @returns most resolved (nearest) form of the object
*/
// XXX should we re-do this?
Q.nearer = nearer;
function nearer(value) {
if (isPromise(value)) {
var inspected = value.inspect();
if (inspected.state === "fulfilled") {
return inspected.value;
}
}
return value;
}
/**
* @returns whether the given object is a promise.
* Otherwise it is a fulfilled value.
*/
Q.isPromise = isPromise;
function isPromise(object) {
return object instanceof Promise;
}
Q.isPromiseAlike = isPromiseAlike;
function isPromiseAlike(object) {
return isObject(object) && typeof object.then === "function";
}
/**
* @returns whether the given object is a pending promise, meaning not
* fulfilled or rejected.
*/
Q.isPending = isPending;
function isPending(object) {
return isPromise(object) && object.inspect().state === "pending";
}
Promise.prototype.isPending = function () {
return this.inspect().state === "pending";
};
/**
* @returns whether the given object is a value or fulfilled
* promise.
*/
Q.isFulfilled = isFulfilled;
function isFulfilled(object) {
return !isPromise(object) || object.inspect().state === "fulfilled";
}
Promise.prototype.isFulfilled = function () {
return this.inspect().state === "fulfilled";
};
/**
* @returns whether the given object is a rejected promise.
*/
Q.isRejected = isRejected;
function isRejected(object) {
return isPromise(object) && object.inspect().state === "rejected";
}
Promise.prototype.isRejected = function () {
return this.inspect().state === "rejected";
};
//// BEGIN UNHANDLED REJECTION TRACKING
// This promise library consumes exceptions thrown in handlers so they can be
// handled by a subsequent promise. The exceptions get added to this array when
// they are created, and removed when they are handled. Note that in ES6 or
// shimmed environments, this would naturally be a `Set`.
var unhandledReasons = [];
var unhandledRejections = [];
var reportedUnhandledRejections = [];
var trackUnhandledRejections = true;
function resetUnhandledRejections() {
unhandledReasons.length = 0;
unhandledRejections.length = 0;
if (!trackUnhandledRejections) {
trackUnhandledRejections = true;
}
}
function trackRejection(promise, reason) {
if (!trackUnhandledRejections) {
return;
}
if (typeof process === "object" && typeof process.emit === "function") {
Q.nextTick.runAfter(function () {
if (array_indexOf(unhandledRejections, promise) !== -1) {
process.emit("unhandledRejection", reason, promise);
reportedUnhandledRejections.push(promise);
}
});
}
unhandledRejections.push(promise);
if (reason && typeof reason.stack !== "undefined") {
unhandledReasons.push(reason.stack);
} else {
unhandledReasons.push("(no stack) " + reason);
}
}
function untrackRejection(promise) {
if (!trackUnhandledRejections) {
return;
}
var at = array_indexOf(unhandledRejections, promise);
if (at !== -1) {
if (typeof process === "object" && typeof process.emit === "function") {
Q.nextTick.runAfter(function () {
var atReport = array_indexOf(reportedUnhandledRejections, promise);
if (atReport !== -1) {
process.emit("rejectionHandled", unhandledReasons[at], promise);
reportedUnhandledRejections.splice(atReport, 1);
}
});
}
unhandledRejections.splice(at, 1);
unhandledReasons.splice(at, 1);
}
}
Q.resetUnhandledRejections = resetUnhandledRejections;
Q.getUnhandledReasons = function () {
// Make a copy so that consumers can't interfere with our internal state.
return unhandledReasons.slice();
};
Q.stopUnhandledRejectionTracking = function () {
resetUnhandledRejections();
trackUnhandledRejections = false;
};
resetUnhandledRejections();
//// END UNHANDLED REJECTION TRACKING
/**
* Constructs a rejected promise.
* @param reason value describing the failure
*/
Q.reject = reject;
function reject(reason) {
var rejection = Promise({
"when": function (rejected) {
// note that the error has been handled
if (rejected) {
untrackRejection(this);
}
return rejected ? rejected(reason) : this;
}
}, function fallback() {
return this;
}, function inspect() {
return { state: "rejected", reason: reason };
});
// Note that the reason has not been handled.
trackRejection(rejection, reason);
return rejection;
}
/**
* Constructs a fulfilled promise for an immediate reference.
* @param value immediate reference
*/
Q.fulfill = fulfill;
function fulfill(value) {
return Promise({
"when": function () {
return value;
},
"get": function (name) {
return value[name];
},
"set": function (name, rhs) {
value[name] = rhs;
},
"delete": function (name) {
delete value[name];
},
"post": function (name, args) {
// Mark Miller proposes that post with no name should apply a
// promised function.
if (name === null || name === void 0) {
return value.apply(void 0, args);
} else {
return value[name].apply(value, args);
}
},
"apply": function (thisp, args) {
return value.apply(thisp, args);
},
"keys": function () {
return object_keys(value);
}
}, void 0, function inspect() {
return { state: "fulfilled", value: value };
});
}
/**
* Converts thenables to Q promises.
* @param promise thenable promise
* @returns a Q promise
*/
function coerce(promise) {
var deferred = defer();
Q.nextTick(function () {
try {
promise.then(deferred.resolve, deferred.reject, deferred.notify);
} catch (exception) {
deferred.reject(exception);
}
});
return deferred.promise;
}
/**
* Annotates an object such that it will never be
* transferred away from this process over any promise
* communication channel.
* @param object
* @returns promise a wrapping of that object that
* additionally responds to the "isDef" message
* without a rejection.
*/
Q.master = master;
function master(object) {
return Promise({
"isDef": function () {}
}, function fallback(op, args) {
return dispatch(object, op, args);
}, function () {
return Q(object).inspect();
});
}
/**
* Spreads the values of a promised array of arguments into the
* fulfillment callback.
* @param fulfilled callback that receives variadic arguments from the
* promised array
* @param rejected callback that receives the exception if the promise
* is rejected.
* @returns a promise for the return value or thrown exception of
* either callback.
*/
Q.spread = spread;
function spread(value, fulfilled, rejected) {
return Q(value).spread(fulfilled, rejected);
}
Promise.prototype.spread = function (fulfilled, rejected) {
return this.all().then(function (array) {
return fulfilled.apply(void 0, array);
}, rejected);
};
/**
* The async function is a decorator for generator functions, turning
* them into asynchronous generators. Although generators are only part
* of the newest ECMAScript 6 drafts, this code does not cause syntax
* errors in older engines. This code should continue to work and will
* in fact improve over time as the language improves.
*
* ES6 generators are currently part of V8 version 3.19 with the
* --harmony-generators runtime flag enabled. SpiderMonkey has had them
* for longer, but under an older Python-inspired form. This function
* works on both kinds of generators.
*
* Decorates a generator function such that:
* - it may yield promises
* - execution will continue when that promise is fulfilled
* - the value of the yield expression will be the fulfilled value
* - it returns a promise for the return value (when the generator
* stops iterating)
* - the decorated function returns a promise for the return value
* of the generator or the first rejected promise among those
* yielded.
* - if an error is thrown in the generator, it propagates through
* every following yield until it is caught, or until it escapes
* the generator function altogether, and is translated into a
* rejection for the promise returned by the decorated generator.
*/
Q.async = async;
function async(makeGenerator) {
return function () {
// when verb is "send", arg is a value
// when verb is "throw", arg is an exception
function continuer(verb, arg) {
var result;
// Until V8 3.19 / Chromium 29 is released, SpiderMonkey is the only
// engine that has a deployed base of browsers that support generators.
// However, SM's generators use the Python-inspired semantics of
// outdated ES6 drafts. We would like to support ES6, but we'd also
// like to make it possible to use generators in deployed browsers, so
// we also support Python-style generators. At some point we can remove
// this block.
if (typeof StopIteration === "undefined") {
// ES6 Generators
try {
result = generator[verb](arg);
} catch (exception) {
return reject(exception);
}
if (result.done) {
return Q(result.value);
} else {
return when(result.value, callback, errback);
}
} else {
// SpiderMonkey Generators
// FIXME: Remove this case when SM does ES6 generators.
try {
result = generator[verb](arg);
} catch (exception) {
if (isStopIteration(exception)) {
return Q(exception.value);
} else {
return reject(exception);
}
}
return when(result, callback, errback);
}
}
var generator = makeGenerator.apply(this, arguments);
var callback = continuer.bind(continuer, "next");
var errback = continuer.bind(continuer, "throw");
return callback();
};
}
/**
* The spawn function is a small wrapper around async that immediately
* calls the generator and also ends the promise chain, so that any
* unhandled errors are thrown instead of forwarded to the error
* handler. This is useful because it's extremely common to run
* generators at the top-level to work with libraries.
*/
Q.spawn = spawn;
function spawn(makeGenerator) {
Q.done(Q.async(makeGenerator)());
}
// FIXME: Remove this interface once ES6 generators are in SpiderMonkey.
/**
* Throws a ReturnValue exception to stop an asynchronous generator.
*
* This interface is a stop-gap measure to support generator return
* values in older Firefox/SpiderMonkey. In browsers that support ES6
* generators like Chromium 29, just use "return" in your generator
* functions.
*
* @param value the return value for the surrounding generator
* @throws ReturnValue exception with the value.
* @example
* // ES6 style
* Q.async(function* () {
* var foo = yield getFooPromise();
* var bar = yield getBarPromise();
* return foo + bar;
* })
* // Older SpiderMonkey style
* Q.async(function () {
* var foo = yield getFooPromise();
* var bar = yield getBarPromise();
* Q.return(foo + bar);
* })
*/
Q["return"] = _return;
function _return(value) {
throw new QReturnValue(value);
}
/**
* The promised function decorator ensures that any promise arguments
* are settled and passed as values (`this` is also settled and passed
* as a value). It will also ensure that the result of a function is
* always a promise.
*
* @example
* var add = Q.promised(function (a, b) {
* return a + b;
* });
* add(Q(a), Q(B));
*
* @param {function} callback The function to decorate
* @returns {function} a function that has been decorated.
*/
Q.promised = promised;
function promised(callback) {
return function () {
return spread([this, all(arguments)], function (self, args) {
return callback.apply(self, args);
});
};
}
/**
* sends a message to a value in a future turn
* @param object* the recipient
* @param op the name of the message operation, e.g., "when",
* @param args further arguments to be forwarded to the operation
* @returns result {Promise} a promise for the result of the operation
*/
Q.dispatch = dispatch;
function dispatch(object, op, args) {
return Q(object).dispatch(op, args);
}
Promise.prototype.dispatch = function (op, args) {
var self = this;
var deferred = defer();
Q.nextTick(function () {
self.promiseDispatch(deferred.resolve, op, args);
});
return deferred.promise;
};
/**
* Gets the value of a property in a future turn.
* @param object promise or immediate reference for target object
* @param name name of property to get
* @return promise for the property value
*/
Q.get = function (object, key) {
return Q(object).dispatch("get", [key]);
};
Promise.prototype.get = function (key) {
return this.dispatch("get", [key]);
};
/**
* Sets the value of a property in a future turn.
* @param object promise or immediate reference for object object
* @param name name of property to set
* @param value new value of property
* @return promise for the return value
*/
Q.set = function (object, key, value) {
return Q(object).dispatch("set", [key, value]);
};
Promise.prototype.set = function (key, value) {
return this.dispatch("set", [key, value]);
};
/**
* Deletes a property in a future turn.
* @param object promise or immediate reference for target object
* @param name name of property to delete
* @return promise for the return value
*/
Q.del = // XXX legacy
Q["delete"] = function (object, key) {
return Q(object).dispatch("delete", [key]);
};
Promise.prototype.del = // XXX legacy
Promise.prototype["delete"] = function (key) {
return this.dispatch("delete", [key]);
};
/**
* Invokes a method in a future turn.
* @param object promise or immediate reference for target object
* @param name name of method to invoke
* @param value a value to post, typically an array of
* invocation arguments for promises that
* are ultimately backed with `resolve` values,
* as opposed to those backed with URLs
* wherein the posted value can be any
* JSON serializable object.
* @return promise for the return value
*/
// bound locally because it is used by other methods
Q.mapply = // XXX As proposed by "Redsandro"
Q.post = function (object, name, args) {
return Q(object).dispatch("post", [name, args]);
};
Promise.prototype.mapply = // XXX As proposed by "Redsandro"
Promise.prototype.post = function (name, args) {
return this.dispatch("post", [name, args]);
};
/**
* Invokes a method in a future turn.
* @param object promise or immediate reference for target object
* @param name name of method to invoke
* @param ...args array of invocation arguments
* @return promise for the return value
*/
Q.send = // XXX Mark Miller's proposed parlance
Q.mcall = // XXX As proposed by "Redsandro"
Q.invoke = function (object, name /*...args*/) {
return Q(object).dispatch("post", [name, array_slice(arguments, 2)]);
};
Promise.prototype.send = // XXX Mark Miller's proposed parlance
Promise.prototype.mcall = // XXX As proposed by "Redsandro"
Promise.prototype.invoke = function (name /*...args*/) {
return this.dispatch("post", [name, array_slice(arguments, 1)]);
};
/**
* Applies the promised function in a future turn.
* @param object promise or immediate reference for target function
* @param args array of application arguments
*/
Q.fapply = function (object, args) {
return Q(object).dispatch("apply", [void 0, args]);
};
Promise.prototype.fapply = function (args) {
return this.dispatch("apply", [void 0, args]);
};
/**
* Calls the promised function in a future turn.
* @param object promise or immediate reference for target function
* @param ...args array of application arguments
*/
Q["try"] =
Q.fcall = function (object /* ...args*/) {
return Q(object).dispatch("apply", [void 0, array_slice(arguments, 1)]);
};
Promise.prototype.fcall = function (/*...args*/) {
return this.dispatch("apply", [void 0, array_slice(arguments)]);
};
/**
* Binds the promised function, transforming return values into a fulfilled
* promise and thrown errors into a rejected one.
* @param object promise or immediate reference for target function
* @param ...args array of application arguments
*/
Q.fbind = function (object /*...args*/) {
var promise = Q(object);
var args = array_slice(arguments, 1);
return function fbound() {
return promise.dispatch("apply", [
this,
args.concat(array_slice(arguments))
]);
};
};
Promise.prototype.fbind = function (/*...args*/) {
var promise = this;
var args = array_slice(arguments);
return function fbound() {
return promise.dispatch("apply", [
this,
args.concat(array_slice(arguments))
]);
};
};
/**
* Requests the names of the owned properties of a promised
* object in a future turn.
* @param object promise or immediate reference for target object
* @return promise for the keys of the eventually settled object
*/
Q.keys = function (object) {
return Q(object).dispatch("keys", []);
};
Promise.prototype.keys = function () {
return this.dispatch("keys", []);
};
/**
* Turns an array of promises into a promise for an array. If any of
* the promises gets rejected, the whole array is rejected immediately.
* @param {Array*} an array (or promise for an array) of values (or
* promises for values)
* @returns a promise for an array of the corresponding values
*/
// By Mark Miller
// http://wiki.ecmascript.org/doku.php?id=strawman:concurrency&rev=1308776521#allfulfilled
Q.all = all;
function all(promises) {
return when(promises, function (promises) {
var pendingCount = 0;
var deferred = defer();
array_reduce(promises, function (undefined, promise, index) {
var snapshot;
if (
isPromise(promise) &&
(snapshot = promise.inspect()).state === "fulfilled"
) {
promises[index] = snapshot.value;
} else {
++pendingCount;
when(
promise,
function (value) {
promises[index] = value;
if (--pendingCount === 0) {
deferred.resolve(promises);
}
},
deferred.reject,
function (progress) {
deferred.notify({ index: index, value: progress });
}
);
}
}, void 0);
if (pendingCount === 0) {
deferred.resolve(promises);
}
return deferred.promise;
});
}
Promise.prototype.all = function () {
return all(this);
};
/**
* Returns the first resolved promise of an array. Prior rejected promises are
* ignored. Rejects only if all promises are rejected.
* @param {Array*} an array containing values or promises for values
* @returns a promise fulfilled with the value of the first resolved promise,
* or a rejected promise if all promises are rejected.
*/
Q.any = any;
function any(promises) {
if (promises.length === 0) {
return Q.resolve();
}
var deferred = Q.defer();
var pendingCount = 0;
array_reduce(promises, function (prev, current, index) {
var promise = promises[index];
pendingCount++;
when(promise, onFulfilled, onRejected, onProgress);
function onFulfilled(result) {
deferred.resolve(result);
}
function onRejected(err) {
pendingCount--;
if (pendingCount === 0) {
var rejection = err || new Error("" + err);
rejection.message = ("Q can't get fulfillment value from any promise, all " +
"promises were rejected. Last error message: " + rejection.message);
deferred.reject(rejection);
}
}
function onProgress(progress) {
deferred.notify({
index: index,
value: progress
});
}
}, undefined);
return deferred.promise;
}
Promise.prototype.any = function () {
return any(this);
};
/**
* Waits for all promises to be settled, either fulfilled or
* rejected. This is distinct from `all` since that would stop
* waiting at the first rejection. The promise returned by
* `allResolved` will never be rejected.
* @param promises a promise for an array (or an array) of promises
* (or values)
* @return a promise for an array of promises
*/
Q.allResolved = deprecate(allResolved, "allResolved", "allSettled");
function allResolved(promises) {
return when(promises, function (promises) {
promises = array_map(promises, Q);
return when(all(array_map(promises, function (promise) {
return when(promise, noop, noop);
})), function () {
return promises;
});
});
}
Promise.prototype.allResolved = function () {
return allResolved(this);
};
/**
* @see Promise#allSettled
*/
Q.allSettled = allSettled;
function allSettled(promises) {
return Q(promises).allSettled();
}
/**
* Turns an array of promises into a promise for an array of their states (as
* returned by `inspect`) when they have all settled.
* @param {Array[Any*]} values an array (or promise for an array) of values (or
* promises for values)
* @returns {Array[State]} an array of states for the respective values.
*/
Promise.prototype.allSettled = function () {
return this.then(function (promises) {
return all(array_map(promises, function (promise) {
promise = Q(promise);
function regardless() {
return promise.inspect();
}
return promise.then(regardless, regardless);
}));
});
};
/**
* Captures the failure of a promise, giving an oportunity to recover
* with a callback. If the given promise is fulfilled, the returned
* promise is fulfilled.
* @param {Any*} promise for something
* @param {Function} callback to fulfill the returned promise if the
* given promise is rejected
* @returns a promise for the return value of the callback
*/
Q.fail = // XXX legacy
Q["catch"] = function (object, rejected) {
return Q(object).then(void 0, rejected);
};
Promise.prototype.fail = // XXX legacy
Promise.prototype["catch"] = function (rejected) {
return this.then(void 0, rejected);
};
/**
* Attaches a listener that can respond to progress notifications from a
* promise's originating deferred. This listener receives the exact arguments
* passed to ``deferred.notify``.
* @param {Any*} promise for something
* @param {Function} callback to receive any progress notifications
* @returns the given promise, unchanged
*/
Q.progress = progress;
function progress(object, progressed) {
return Q(object).then(void 0, void 0, progressed);
}
Promise.prototype.progress = function (progressed) {
return this.then(void 0, void 0, progressed);
};
/**
* Provides an opportunity to observe the settling of a promise,
* regardless of whether the promise is fulfilled or rejected. Forwards
* the resolution to the returned promise when the callback is done.
* The callback can return a promise to defer completion.
* @param {Any*} promise
* @param {Function} callback to observe the resolution of the given
* promise, takes no arguments.
* @returns a promise for the resolution of the given promise when
* ``fin`` is done.
*/
Q.fin = // XXX legacy
Q["finally"] = function (object, callback) {
return Q(object)["finally"](callback);
};
Promise.prototype.fin = // XXX legacy
Promise.prototype["finally"] = function (callback) {
if (!callback || typeof callback.apply !== "function") {
throw new Error("Q can't apply finally callback");
}
callback = Q(callback);
return this.then(function (value) {
return callback.fcall().then(function () {
return value;
});
}, function (reason) {
// TODO attempt to recycle the rejection with "this".
return callback.fcall().then(function () {
throw reason;
});
});
};
/**
* Terminates a chain of promises, forcing rejections to be
* thrown as exceptions.
* @param {Any*} promise at the end of a chain of promises
* @returns nothing
*/
Q.done = function (object, fulfilled, rejected, progress) {
return Q(object).done(fulfilled, rejected, progress);
};
Promise.prototype.done = function (fulfilled, rejected, progress) {
var onUnhandledError = function (error) {
// forward to a future turn so that ``when``
// does not catch it and turn it into a rejection.
Q.nextTick(function () {
makeStackTraceLong(error, promise);
if (Q.onerror) {
Q.onerror(error);
} else {
throw error;
}
});
};
// Avoid unnecessary `nextTick`ing via an unnecessary `when`.
var promise = fulfilled || rejected || progress ?
this.then(fulfilled, rejected, progress) :
this;
if (typeof process === "object" && process && process.domain) {
onUnhandledError = process.domain.bind(onUnhandledError);
}
promise.then(void 0, onUnhandledError);
};
/**
* Causes a promise to be rejected if it does not get fulfilled before
* some milliseconds time out.
* @param {Any*} promise
* @param {Number} milliseconds timeout
* @param {Any*} custom error message or Error object (optional)
* @returns a promise for the resolution of the given promise if it is
* fulfilled before the timeout, otherwise rejected.
*/
Q.timeout = function (object, ms, error) {
return Q(object).timeout(ms, error);
};
Promise.prototype.timeout = function (ms, error) {
var deferred = defer();
var timeoutId = setTimeout(function () {
if (!error || "string" === typeof error) {
error = new Error(error || "Timed out after " + ms + " ms");
error.code = "ETIMEDOUT";
}
deferred.reject(error);
}, ms);
this.then(function (value) {
clearTimeout(timeoutId);
deferred.resolve(value);
}, function (exception) {
clearTimeout(timeoutId);
deferred.reject(exception);
}, deferred.notify);
return deferred.promise;
};
/**
* Returns a promise for the given value (or promised value), some
* milliseconds after it resolved. Passes rejections immediately.
* @param {Any*} promise
* @param {Number} milliseconds
* @returns a promise for the resolution of the given promise after milliseconds
* time has elapsed since the resolution of the given promise.
* If the given promise rejects, that is passed immediately.
*/
Q.delay = function (object, timeout) {
if (timeout === void 0) {
timeout = object;
object = void 0;
}
return Q(object).delay(timeout);
};
Promise.prototype.delay = function (timeout) {
return this.then(function (value) {
var deferred = defer();
setTimeout(function () {
deferred.resolve(value);
}, timeout);
return deferred.promise;
});
};
/**
* Passes a continuation to a Node function, which is called with the given
* arguments provided as an array, and returns a promise.
*
* Q.nfapply(FS.readFile, [__filename])
* .then(function (content) {
* })
*
*/
Q.nfapply = function (callback, args) {
return Q(callback).nfapply(args);
};
Promise.prototype.nfapply = function (args) {
var deferred = defer();
var nodeArgs = array_slice(args);
nodeArgs.push(deferred.makeNodeResolver());
this.fapply(nodeArgs).fail(deferred.reject);
return deferred.promise;
};
/**
* Passes a continuation to a Node function, which is called with the given
* arguments provided individually, and returns a promise.
* @example
* Q.nfcall(FS.readFile, __filename)
* .then(function (content) {
* })
*
*/
Q.nfcall = function (callback /*...args*/) {
var args = array_slice(arguments, 1);
return Q(callback).nfapply(args);
};
Promise.prototype.nfcall = function (/*...args*/) {
var nodeArgs = array_slice(arguments);
var deferred = defer();
nodeArgs.push(deferred.makeNodeResolver());
this.fapply(nodeArgs).fail(deferred.reject);
return deferred.promise;
};
/**
* Wraps a NodeJS continuation passing function and returns an equivalent
* version that returns a promise.
* @example
* Q.nfbind(FS.readFile, __filename)("utf-8")
* .then(console.log)
* .done()
*/
Q.nfbind =
Q.denodeify = function (callback /*...args*/) {
if (callback === undefined) {
throw new Error("Q can't wrap an undefined function");
}
var baseArgs = array_slice(arguments, 1);
return function () {
var nodeArgs = baseArgs.concat(array_slice(arguments));
var deferred = defer();
nodeArgs.push(deferred.makeNodeResolver());
Q(callback).fapply(nodeArgs).fail(deferred.reject);
return deferred.promise;
};
};
Promise.prototype.nfbind =
Promise.prototype.denodeify = function (/*...args*/) {
var args = array_slice(arguments);
args.unshift(this);
return Q.denodeify.apply(void 0, args);
};
Q.nbind = function (callback, thisp /*...args*/) {
var baseArgs = array_slice(arguments, 2);
return function () {
var nodeArgs = baseArgs.concat(array_slice(arguments));
var deferred = defer();
nodeArgs.push(deferred.makeNodeResolver());
function bound() {
return callback.apply(thisp, arguments);
}
Q(bound).fapply(nodeArgs).fail(deferred.reject);
return deferred.promise;
};
};
Promise.prototype.nbind = function (/*thisp, ...args*/) {
var args = array_slice(arguments, 0);
args.unshift(this);
return Q.nbind.apply(void 0, args);
};
/**
* Calls a method of a Node-style object that accepts a Node-style
* callback with a given array of arguments, plus a provided callback.
* @param object an object that has the named method
* @param {String} name name of the method of object
* @param {Array} args arguments to pass to the method; the callback
* will be provided by Q and appended to these arguments.
* @returns a promise for the value or error
*/
Q.nmapply = // XXX As proposed by "Redsandro"
Q.npost = function (object, name, args) {
return Q(object).npost(name, args);
};
Promise.prototype.nmapply = // XXX As proposed by "Redsandro"
Promise.prototype.npost = function (name, args) {
var nodeArgs = array_slice(args || []);
var deferred = defer();
nodeArgs.push(deferred.makeNodeResolver());
this.dispatch("post", [name, nodeArgs]).fail(deferred.reject);
return deferred.promise;
};
/**
* Calls a method of a Node-style object that accepts a Node-style
* callback, forwarding the given variadic arguments, plus a provided
* callback argument.
* @param object an object that has the named method
* @param {String} name name of the method of object
* @param ...args arguments to pass to the method; the callback will
* be provided by Q and appended to these arguments.
* @returns a promise for the value or error
*/
Q.nsend = // XXX Based on Mark Miller's proposed "send"
Q.nmcall = // XXX Based on "Redsandro's" proposal
Q.ninvoke = function (object, name /*...args*/) {
var nodeArgs = array_slice(arguments, 2);
var deferred = defer();
nodeArgs.push(deferred.makeNodeResolver());
Q(object).dispatch("post", [name, nodeArgs]).fail(deferred.reject);
return deferred.promise;
};
Promise.prototype.nsend = // XXX Based on Mark Miller's proposed "send"
Promise.prototype.nmcall = // XXX Based on "Redsandro's" proposal
Promise.prototype.ninvoke = function (name /*...args*/) {
var nodeArgs = array_slice(arguments, 1);
var deferred = defer();
nodeArgs.push(deferred.makeNodeResolver());
this.dispatch("post", [name, nodeArgs]).fail(deferred.reject);
return deferred.promise;
};
/**
* If a function would like to support both Node continuation-passing-style and
* promise-returning-style, it can end its internal promise chain with
* `nodeify(nodeback)`, forwarding the optional nodeback argument. If the user
* elects to use a nodeback, the result will be sent there. If they do not
* pass a nodeback, they will receive the result promise.
* @param object a result (or a promise for a result)
* @param {Function} nodeback a Node.js-style callback
* @returns either the promise or nothing
*/
Q.nodeify = nodeify;
function nodeify(object, nodeback) {
return Q(object).nodeify(nodeback);
}
Promise.prototype.nodeify = function (nodeback) {
if (nodeback) {
this.then(function (value) {
Q.nextTick(function () {
nodeback(null, value);
});
}, function (error) {
Q.nextTick(function () {
nodeback(error);
});
});
} else {
return this;
}
};
Q.noConflict = function() {
throw new Error("Q.noConflict only works when Q is used as a global");
};
// All code before this point will be filtered from stack traces.
var qEndingLine = captureLine();
return Q;
});