bind.js

"use strict";
module.exports = function(Promise, INTERNAL, tryConvertToPromise) {
var rejectThis = function(_, e) {
    this._reject(e);
};

var targetRejected = function(e, context) {
    context.promiseRejectionQueued = true;
    context.bindingPromise._then(rejectThis, rejectThis, null, this, e);
};

var bindingResolved = function(thisArg, context) {
    this._setBoundTo(thisArg);
    if (this._isPending()) {
        this._resolveCallback(context.target);
    }
};

var bindingRejected = function(e, context) {
    if (!context.promiseRejectionQueued) this._reject(e);
};

Promise.prototype.bind = function (thisArg) {
    var maybePromise = tryConvertToPromise(thisArg);
    var ret = new Promise(INTERNAL);
    ret._propagateFrom(this, 1);
    var target = this._target();
    if (maybePromise instanceof Promise) {
        var context = {
            promiseRejectionQueued: false,
            promise: ret,
            target: target,
            bindingPromise: maybePromise
        };
        target._then(INTERNAL, targetRejected, ret._progress, ret, context);
        maybePromise._then(
            bindingResolved, bindingRejected, ret._progress, ret, context);
    } else {
        ret._setBoundTo(thisArg);
        ret._resolveCallback(target);
    }
    return ret;
};

Promise.prototype._setBoundTo = function (obj) {
    if (obj !== undefined) {
        this._bitField = this._bitField | 131072;
        this._boundTo = obj;
    } else {
        this._bitField = this._bitField & (~131072);
    }
};

Promise.prototype._isBound = function () {
    return (this._bitField & 131072) === 131072;
};

Promise.bind = function (thisArg, value) {
    var maybePromise = tryConvertToPromise(thisArg);
    var ret = new Promise(INTERNAL);

    if (maybePromise instanceof Promise) {
        maybePromise._then(function(thisArg) {
            ret._setBoundTo(thisArg);
            ret._resolveCallback(value);
        }, ret._reject, ret._progress, ret, null);
    } else {
        ret._setBoundTo(thisArg);
        ret._resolveCallback(value);
    }
    return ret;
};
};