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- "use strict";
- module.exports = function (Promise, apiRejection, tryConvertToPromise,
- createContext, INTERNAL, debug) {
- var util = require("./util");
- var TypeError = require("./errors").TypeError;
- var inherits = require("./util").inherits;
- var errorObj = util.errorObj;
- var tryCatch = util.tryCatch;
- var NULL = {};
-
- function thrower(e) {
- setTimeout(function(){throw e;}, 0);
- }
-
- function castPreservingDisposable(thenable) {
- var maybePromise = tryConvertToPromise(thenable);
- if (maybePromise !== thenable &&
- typeof thenable._isDisposable === "function" &&
- typeof thenable._getDisposer === "function" &&
- thenable._isDisposable()) {
- maybePromise._setDisposable(thenable._getDisposer());
- }
- return maybePromise;
- }
- function dispose(resources, inspection) {
- var i = 0;
- var len = resources.length;
- var ret = new Promise(INTERNAL);
- function iterator() {
- if (i >= len) return ret._fulfill();
- var maybePromise = castPreservingDisposable(resources[i++]);
- if (maybePromise instanceof Promise &&
- maybePromise._isDisposable()) {
- try {
- maybePromise = tryConvertToPromise(
- maybePromise._getDisposer().tryDispose(inspection),
- resources.promise);
- } catch (e) {
- return thrower(e);
- }
- if (maybePromise instanceof Promise) {
- return maybePromise._then(iterator, thrower,
- null, null, null);
- }
- }
- iterator();
- }
- iterator();
- return ret;
- }
-
- function Disposer(data, promise, context) {
- this._data = data;
- this._promise = promise;
- this._context = context;
- }
-
- Disposer.prototype.data = function () {
- return this._data;
- };
-
- Disposer.prototype.promise = function () {
- return this._promise;
- };
-
- Disposer.prototype.resource = function () {
- if (this.promise().isFulfilled()) {
- return this.promise().value();
- }
- return NULL;
- };
-
- Disposer.prototype.tryDispose = function(inspection) {
- var resource = this.resource();
- var context = this._context;
- if (context !== undefined) context._pushContext();
- var ret = resource !== NULL
- ? this.doDispose(resource, inspection) : null;
- if (context !== undefined) context._popContext();
- this._promise._unsetDisposable();
- this._data = null;
- return ret;
- };
-
- Disposer.isDisposer = function (d) {
- return (d != null &&
- typeof d.resource === "function" &&
- typeof d.tryDispose === "function");
- };
-
- function FunctionDisposer(fn, promise, context) {
- this.constructor$(fn, promise, context);
- }
- inherits(FunctionDisposer, Disposer);
-
- FunctionDisposer.prototype.doDispose = function (resource, inspection) {
- var fn = this.data();
- return fn.call(resource, resource, inspection);
- };
-
- function maybeUnwrapDisposer(value) {
- if (Disposer.isDisposer(value)) {
- this.resources[this.index]._setDisposable(value);
- return value.promise();
- }
- return value;
- }
-
- function ResourceList(length) {
- this.length = length;
- this.promise = null;
- this[length-1] = null;
- }
-
- ResourceList.prototype._resultCancelled = function() {
- var len = this.length;
- for (var i = 0; i < len; ++i) {
- var item = this[i];
- if (item instanceof Promise) {
- item.cancel();
- }
- }
- };
-
- Promise.using = function () {
- var len = arguments.length;
- if (len < 2) return apiRejection(
- "you must pass at least 2 arguments to Promise.using");
- var fn = arguments[len - 1];
- if (typeof fn !== "function") {
- return apiRejection("expecting a function but got " + util.classString(fn));
- }
- var input;
- var spreadArgs = true;
- if (len === 2 && Array.isArray(arguments[0])) {
- input = arguments[0];
- len = input.length;
- spreadArgs = false;
- } else {
- input = arguments;
- len--;
- }
- var resources = new ResourceList(len);
- for (var i = 0; i < len; ++i) {
- var resource = input[i];
- if (Disposer.isDisposer(resource)) {
- var disposer = resource;
- resource = resource.promise();
- resource._setDisposable(disposer);
- } else {
- var maybePromise = tryConvertToPromise(resource);
- if (maybePromise instanceof Promise) {
- resource =
- maybePromise._then(maybeUnwrapDisposer, null, null, {
- resources: resources,
- index: i
- }, undefined);
- }
- }
- resources[i] = resource;
- }
-
- var reflectedResources = new Array(resources.length);
- for (var i = 0; i < reflectedResources.length; ++i) {
- reflectedResources[i] = Promise.resolve(resources[i]).reflect();
- }
-
- var resultPromise = Promise.all(reflectedResources)
- .then(function(inspections) {
- for (var i = 0; i < inspections.length; ++i) {
- var inspection = inspections[i];
- if (inspection.isRejected()) {
- errorObj.e = inspection.error();
- return errorObj;
- } else if (!inspection.isFulfilled()) {
- resultPromise.cancel();
- return;
- }
- inspections[i] = inspection.value();
- }
- promise._pushContext();
-
- fn = tryCatch(fn);
- var ret = spreadArgs
- ? fn.apply(undefined, inspections) : fn(inspections);
- var promiseCreated = promise._popContext();
- debug.checkForgottenReturns(
- ret, promiseCreated, "Promise.using", promise);
- return ret;
- });
-
- var promise = resultPromise.lastly(function() {
- var inspection = new Promise.PromiseInspection(resultPromise);
- return dispose(resources, inspection);
- });
- resources.promise = promise;
- promise._setOnCancel(resources);
- return promise;
- };
-
- Promise.prototype._setDisposable = function (disposer) {
- this._bitField = this._bitField | 131072;
- this._disposer = disposer;
- };
-
- Promise.prototype._isDisposable = function () {
- return (this._bitField & 131072) > 0;
- };
-
- Promise.prototype._getDisposer = function () {
- return this._disposer;
- };
-
- Promise.prototype._unsetDisposable = function () {
- this._bitField = this._bitField & (~131072);
- this._disposer = undefined;
- };
-
- Promise.prototype.disposer = function (fn) {
- if (typeof fn === "function") {
- return new FunctionDisposer(fn, this, createContext());
- }
- throw new TypeError();
- };
-
- };
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