mirror of
https://github.com/neocities/neocities.git
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843 lines
27 KiB
JavaScript
843 lines
27 KiB
JavaScript
/*---------------------------------------------------------------------------------------------
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* Copyright (c) Microsoft Corporation. All rights reserved.
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* Licensed under the MIT License. See License.txt in the project root for license information.
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*--------------------------------------------------------------------------------------------*/
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import { CancellationTokenSource } from './cancellation.js';
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import { BugIndicatingError, CancellationError } from './errors.js';
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import { Emitter, Event } from './event.js';
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import { toDisposable } from './lifecycle.js';
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import { setTimeout0 } from './platform.js';
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import { MicrotaskDelay } from './symbols.js';
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export function isThenable(obj) {
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return !!obj && typeof obj.then === 'function';
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}
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export function createCancelablePromise(callback) {
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const source = new CancellationTokenSource();
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const thenable = callback(source.token);
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const promise = new Promise((resolve, reject) => {
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const subscription = source.token.onCancellationRequested(() => {
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subscription.dispose();
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reject(new CancellationError());
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});
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Promise.resolve(thenable).then(value => {
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subscription.dispose();
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source.dispose();
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resolve(value);
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}, err => {
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subscription.dispose();
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source.dispose();
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reject(err);
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});
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});
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return new class {
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cancel() {
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source.cancel();
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source.dispose();
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}
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then(resolve, reject) {
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return promise.then(resolve, reject);
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}
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catch(reject) {
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return this.then(undefined, reject);
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}
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finally(onfinally) {
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return promise.finally(onfinally);
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}
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};
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}
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export function raceCancellation(promise, token, defaultValue) {
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return new Promise((resolve, reject) => {
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const ref = token.onCancellationRequested(() => {
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ref.dispose();
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resolve(defaultValue);
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});
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promise.then(resolve, reject).finally(() => ref.dispose());
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});
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}
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/**
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* A helper to prevent accumulation of sequential async tasks.
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*
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* Imagine a mail man with the sole task of delivering letters. As soon as
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* a letter submitted for delivery, he drives to the destination, delivers it
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* and returns to his base. Imagine that during the trip, N more letters were submitted.
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* When the mail man returns, he picks those N letters and delivers them all in a
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* single trip. Even though N+1 submissions occurred, only 2 deliveries were made.
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*
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* The throttler implements this via the queue() method, by providing it a task
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* factory. Following the example:
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*
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* const throttler = new Throttler();
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* const letters = [];
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*
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* function deliver() {
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* const lettersToDeliver = letters;
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* letters = [];
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* return makeTheTrip(lettersToDeliver);
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* }
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*
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* function onLetterReceived(l) {
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* letters.push(l);
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* throttler.queue(deliver);
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* }
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*/
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export class Throttler {
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constructor() {
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this.isDisposed = false;
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this.activePromise = null;
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this.queuedPromise = null;
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this.queuedPromiseFactory = null;
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}
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queue(promiseFactory) {
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if (this.isDisposed) {
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return Promise.reject(new Error('Throttler is disposed'));
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}
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if (this.activePromise) {
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this.queuedPromiseFactory = promiseFactory;
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if (!this.queuedPromise) {
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const onComplete = () => {
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this.queuedPromise = null;
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if (this.isDisposed) {
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return;
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}
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const result = this.queue(this.queuedPromiseFactory);
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this.queuedPromiseFactory = null;
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return result;
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};
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this.queuedPromise = new Promise(resolve => {
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this.activePromise.then(onComplete, onComplete).then(resolve);
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});
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}
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return new Promise((resolve, reject) => {
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this.queuedPromise.then(resolve, reject);
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});
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}
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this.activePromise = promiseFactory();
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return new Promise((resolve, reject) => {
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this.activePromise.then((result) => {
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this.activePromise = null;
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resolve(result);
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}, (err) => {
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this.activePromise = null;
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reject(err);
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});
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});
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}
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dispose() {
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this.isDisposed = true;
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}
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}
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const timeoutDeferred = (timeout, fn) => {
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let scheduled = true;
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const handle = setTimeout(() => {
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scheduled = false;
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fn();
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}, timeout);
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return {
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isTriggered: () => scheduled,
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dispose: () => {
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clearTimeout(handle);
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scheduled = false;
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},
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};
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};
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const microtaskDeferred = (fn) => {
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let scheduled = true;
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queueMicrotask(() => {
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if (scheduled) {
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scheduled = false;
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fn();
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}
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});
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return {
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isTriggered: () => scheduled,
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dispose: () => { scheduled = false; },
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};
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};
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/**
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* A helper to delay (debounce) execution of a task that is being requested often.
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*
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* Following the throttler, now imagine the mail man wants to optimize the number of
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* trips proactively. The trip itself can be long, so he decides not to make the trip
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* as soon as a letter is submitted. Instead he waits a while, in case more
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* letters are submitted. After said waiting period, if no letters were submitted, he
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* decides to make the trip. Imagine that N more letters were submitted after the first
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* one, all within a short period of time between each other. Even though N+1
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* submissions occurred, only 1 delivery was made.
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*
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* The delayer offers this behavior via the trigger() method, into which both the task
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* to be executed and the waiting period (delay) must be passed in as arguments. Following
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* the example:
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*
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* const delayer = new Delayer(WAITING_PERIOD);
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* const letters = [];
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*
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* function letterReceived(l) {
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* letters.push(l);
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* delayer.trigger(() => { return makeTheTrip(); });
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* }
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*/
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export class Delayer {
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constructor(defaultDelay) {
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this.defaultDelay = defaultDelay;
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this.deferred = null;
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this.completionPromise = null;
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this.doResolve = null;
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this.doReject = null;
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this.task = null;
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}
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trigger(task, delay = this.defaultDelay) {
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this.task = task;
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this.cancelTimeout();
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if (!this.completionPromise) {
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this.completionPromise = new Promise((resolve, reject) => {
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this.doResolve = resolve;
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this.doReject = reject;
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}).then(() => {
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this.completionPromise = null;
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this.doResolve = null;
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if (this.task) {
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const task = this.task;
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this.task = null;
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return task();
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}
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return undefined;
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});
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}
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const fn = () => {
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this.deferred = null;
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this.doResolve?.(null);
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};
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this.deferred = delay === MicrotaskDelay ? microtaskDeferred(fn) : timeoutDeferred(delay, fn);
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return this.completionPromise;
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}
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isTriggered() {
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return !!this.deferred?.isTriggered();
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}
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cancel() {
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this.cancelTimeout();
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if (this.completionPromise) {
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this.doReject?.(new CancellationError());
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this.completionPromise = null;
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}
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}
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cancelTimeout() {
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this.deferred?.dispose();
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this.deferred = null;
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}
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dispose() {
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this.cancel();
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}
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}
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/**
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* A helper to delay execution of a task that is being requested often, while
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* preventing accumulation of consecutive executions, while the task runs.
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*
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* The mail man is clever and waits for a certain amount of time, before going
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* out to deliver letters. While the mail man is going out, more letters arrive
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* and can only be delivered once he is back. Once he is back the mail man will
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* do one more trip to deliver the letters that have accumulated while he was out.
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*/
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export class ThrottledDelayer {
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constructor(defaultDelay) {
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this.delayer = new Delayer(defaultDelay);
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this.throttler = new Throttler();
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}
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trigger(promiseFactory, delay) {
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return this.delayer.trigger(() => this.throttler.queue(promiseFactory), delay);
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}
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cancel() {
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this.delayer.cancel();
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}
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dispose() {
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this.delayer.dispose();
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this.throttler.dispose();
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}
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}
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export function timeout(millis, token) {
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if (!token) {
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return createCancelablePromise(token => timeout(millis, token));
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}
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return new Promise((resolve, reject) => {
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const handle = setTimeout(() => {
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disposable.dispose();
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resolve();
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}, millis);
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const disposable = token.onCancellationRequested(() => {
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clearTimeout(handle);
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disposable.dispose();
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reject(new CancellationError());
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});
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});
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}
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/**
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* Creates a timeout that can be disposed using its returned value.
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* @param handler The timeout handler.
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* @param timeout An optional timeout in milliseconds.
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* @param store An optional {@link DisposableStore} that will have the timeout disposable managed automatically.
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*
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* @example
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* const store = new DisposableStore;
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* // Call the timeout after 1000ms at which point it will be automatically
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* // evicted from the store.
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* const timeoutDisposable = disposableTimeout(() => {}, 1000, store);
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*
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* if (foo) {
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* // Cancel the timeout and evict it from store.
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* timeoutDisposable.dispose();
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* }
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*/
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export function disposableTimeout(handler, timeout = 0, store) {
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const timer = setTimeout(() => {
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handler();
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if (store) {
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disposable.dispose();
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}
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}, timeout);
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const disposable = toDisposable(() => {
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clearTimeout(timer);
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store?.deleteAndLeak(disposable);
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});
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store?.add(disposable);
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return disposable;
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}
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export function first(promiseFactories, shouldStop = t => !!t, defaultValue = null) {
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let index = 0;
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const len = promiseFactories.length;
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const loop = () => {
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if (index >= len) {
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return Promise.resolve(defaultValue);
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}
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const factory = promiseFactories[index++];
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const promise = Promise.resolve(factory());
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return promise.then(result => {
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if (shouldStop(result)) {
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return Promise.resolve(result);
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}
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return loop();
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});
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};
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return loop();
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}
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export class TimeoutTimer {
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constructor(runner, timeout) {
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this._isDisposed = false;
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this._token = -1;
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if (typeof runner === 'function' && typeof timeout === 'number') {
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this.setIfNotSet(runner, timeout);
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}
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}
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dispose() {
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this.cancel();
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this._isDisposed = true;
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}
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cancel() {
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if (this._token !== -1) {
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clearTimeout(this._token);
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this._token = -1;
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}
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}
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cancelAndSet(runner, timeout) {
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if (this._isDisposed) {
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throw new BugIndicatingError(`Calling 'cancelAndSet' on a disposed TimeoutTimer`);
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}
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this.cancel();
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this._token = setTimeout(() => {
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this._token = -1;
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runner();
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}, timeout);
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}
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setIfNotSet(runner, timeout) {
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if (this._isDisposed) {
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throw new BugIndicatingError(`Calling 'setIfNotSet' on a disposed TimeoutTimer`);
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}
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if (this._token !== -1) {
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// timer is already set
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return;
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}
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this._token = setTimeout(() => {
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this._token = -1;
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runner();
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}, timeout);
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}
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}
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export class IntervalTimer {
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constructor() {
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this.disposable = undefined;
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this.isDisposed = false;
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}
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cancel() {
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this.disposable?.dispose();
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this.disposable = undefined;
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}
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cancelAndSet(runner, interval, context = globalThis) {
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if (this.isDisposed) {
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throw new BugIndicatingError(`Calling 'cancelAndSet' on a disposed IntervalTimer`);
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}
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this.cancel();
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const handle = context.setInterval(() => {
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runner();
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}, interval);
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this.disposable = toDisposable(() => {
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context.clearInterval(handle);
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this.disposable = undefined;
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});
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}
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dispose() {
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this.cancel();
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this.isDisposed = true;
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}
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}
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export class RunOnceScheduler {
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constructor(runner, delay) {
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this.timeoutToken = -1;
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this.runner = runner;
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this.timeout = delay;
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this.timeoutHandler = this.onTimeout.bind(this);
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}
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/**
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* Dispose RunOnceScheduler
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*/
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dispose() {
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this.cancel();
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this.runner = null;
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}
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/**
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* Cancel current scheduled runner (if any).
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*/
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cancel() {
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if (this.isScheduled()) {
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clearTimeout(this.timeoutToken);
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this.timeoutToken = -1;
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}
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}
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/**
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* Cancel previous runner (if any) & schedule a new runner.
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*/
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schedule(delay = this.timeout) {
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this.cancel();
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this.timeoutToken = setTimeout(this.timeoutHandler, delay);
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}
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get delay() {
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return this.timeout;
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}
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set delay(value) {
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this.timeout = value;
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}
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/**
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* Returns true if scheduled.
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*/
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isScheduled() {
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return this.timeoutToken !== -1;
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}
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onTimeout() {
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this.timeoutToken = -1;
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if (this.runner) {
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this.doRun();
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}
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}
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doRun() {
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this.runner?.();
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}
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}
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/**
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* Execute the callback the next time the browser is idle, returning an
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* {@link IDisposable} that will cancel the callback when disposed. This wraps
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* [requestIdleCallback] so it will fallback to [setTimeout] if the environment
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* doesn't support it.
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*
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* @param callback The callback to run when idle, this includes an
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* [IdleDeadline] that provides the time alloted for the idle callback by the
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* browser. Not respecting this deadline will result in a degraded user
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* experience.
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* @param timeout A timeout at which point to queue no longer wait for an idle
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* callback but queue it on the regular event loop (like setTimeout). Typically
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* this should not be used.
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*
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* [IdleDeadline]: https://developer.mozilla.org/en-US/docs/Web/API/IdleDeadline
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* [requestIdleCallback]: https://developer.mozilla.org/en-US/docs/Web/API/Window/requestIdleCallback
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* [setTimeout]: https://developer.mozilla.org/en-US/docs/Web/API/Window/setTimeout
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*
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* **Note** that there is `dom.ts#runWhenWindowIdle` which is better suited when running inside a browser
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* context
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*/
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export let runWhenGlobalIdle;
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export let _runWhenIdle;
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(function () {
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if (typeof globalThis.requestIdleCallback !== 'function' || typeof globalThis.cancelIdleCallback !== 'function') {
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_runWhenIdle = (_targetWindow, runner) => {
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setTimeout0(() => {
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if (disposed) {
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return;
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}
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const end = Date.now() + 15; // one frame at 64fps
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const deadline = {
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didTimeout: true,
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timeRemaining() {
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return Math.max(0, end - Date.now());
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}
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};
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runner(Object.freeze(deadline));
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});
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let disposed = false;
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return {
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dispose() {
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if (disposed) {
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return;
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}
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disposed = true;
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}
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};
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};
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}
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else {
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_runWhenIdle = (targetWindow, runner, timeout) => {
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const handle = targetWindow.requestIdleCallback(runner, typeof timeout === 'number' ? { timeout } : undefined);
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let disposed = false;
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return {
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dispose() {
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if (disposed) {
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return;
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}
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disposed = true;
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targetWindow.cancelIdleCallback(handle);
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}
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};
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};
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}
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runWhenGlobalIdle = (runner) => _runWhenIdle(globalThis, runner);
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})();
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export class AbstractIdleValue {
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constructor(targetWindow, executor) {
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this._didRun = false;
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this._executor = () => {
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try {
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this._value = executor();
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}
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catch (err) {
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this._error = err;
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}
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finally {
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this._didRun = true;
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}
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};
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this._handle = _runWhenIdle(targetWindow, () => this._executor());
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}
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dispose() {
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this._handle.dispose();
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}
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get value() {
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if (!this._didRun) {
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this._handle.dispose();
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this._executor();
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}
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if (this._error) {
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throw this._error;
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}
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return this._value;
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}
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get isInitialized() {
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return this._didRun;
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}
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}
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/**
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* An `IdleValue` that always uses the current window (which might be throttled or inactive)
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*
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* **Note** that there is `dom.ts#WindowIdleValue` which is better suited when running inside a browser
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* context
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*/
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export class GlobalIdleValue extends AbstractIdleValue {
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constructor(executor) {
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super(globalThis, executor);
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}
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}
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/**
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* Creates a promise whose resolution or rejection can be controlled imperatively.
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*/
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export class DeferredPromise {
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get isRejected() {
|
|
return this.outcome?.outcome === 1 /* DeferredOutcome.Rejected */;
|
|
}
|
|
get isSettled() {
|
|
return !!this.outcome;
|
|
}
|
|
constructor() {
|
|
this.p = new Promise((c, e) => {
|
|
this.completeCallback = c;
|
|
this.errorCallback = e;
|
|
});
|
|
}
|
|
complete(value) {
|
|
return new Promise(resolve => {
|
|
this.completeCallback(value);
|
|
this.outcome = { outcome: 0 /* DeferredOutcome.Resolved */, value };
|
|
resolve();
|
|
});
|
|
}
|
|
error(err) {
|
|
return new Promise(resolve => {
|
|
this.errorCallback(err);
|
|
this.outcome = { outcome: 1 /* DeferredOutcome.Rejected */, value: err };
|
|
resolve();
|
|
});
|
|
}
|
|
cancel() {
|
|
return this.error(new CancellationError());
|
|
}
|
|
}
|
|
//#endregion
|
|
//#region Promises
|
|
export var Promises;
|
|
(function (Promises) {
|
|
/**
|
|
* A drop-in replacement for `Promise.all` with the only difference
|
|
* that the method awaits every promise to either fulfill or reject.
|
|
*
|
|
* Similar to `Promise.all`, only the first error will be returned
|
|
* if any.
|
|
*/
|
|
async function settled(promises) {
|
|
let firstError = undefined;
|
|
const result = await Promise.all(promises.map(promise => promise.then(value => value, error => {
|
|
if (!firstError) {
|
|
firstError = error;
|
|
}
|
|
return undefined; // do not rethrow so that other promises can settle
|
|
})));
|
|
if (typeof firstError !== 'undefined') {
|
|
throw firstError;
|
|
}
|
|
return result; // cast is needed and protected by the `throw` above
|
|
}
|
|
Promises.settled = settled;
|
|
/**
|
|
* A helper to create a new `Promise<T>` with a body that is a promise
|
|
* itself. By default, an error that raises from the async body will
|
|
* end up as a unhandled rejection, so this utility properly awaits the
|
|
* body and rejects the promise as a normal promise does without async
|
|
* body.
|
|
*
|
|
* This method should only be used in rare cases where otherwise `async`
|
|
* cannot be used (e.g. when callbacks are involved that require this).
|
|
*/
|
|
function withAsyncBody(bodyFn) {
|
|
// eslint-disable-next-line no-async-promise-executor
|
|
return new Promise(async (resolve, reject) => {
|
|
try {
|
|
await bodyFn(resolve, reject);
|
|
}
|
|
catch (error) {
|
|
reject(error);
|
|
}
|
|
});
|
|
}
|
|
Promises.withAsyncBody = withAsyncBody;
|
|
})(Promises || (Promises = {}));
|
|
/**
|
|
* A rich implementation for an `AsyncIterable<T>`.
|
|
*/
|
|
export class AsyncIterableObject {
|
|
static fromArray(items) {
|
|
return new AsyncIterableObject((writer) => {
|
|
writer.emitMany(items);
|
|
});
|
|
}
|
|
static fromPromise(promise) {
|
|
return new AsyncIterableObject(async (emitter) => {
|
|
emitter.emitMany(await promise);
|
|
});
|
|
}
|
|
static fromPromises(promises) {
|
|
return new AsyncIterableObject(async (emitter) => {
|
|
await Promise.all(promises.map(async (p) => emitter.emitOne(await p)));
|
|
});
|
|
}
|
|
static merge(iterables) {
|
|
return new AsyncIterableObject(async (emitter) => {
|
|
await Promise.all(iterables.map(async (iterable) => {
|
|
for await (const item of iterable) {
|
|
emitter.emitOne(item);
|
|
}
|
|
}));
|
|
});
|
|
}
|
|
static { this.EMPTY = AsyncIterableObject.fromArray([]); }
|
|
constructor(executor, onReturn) {
|
|
this._state = 0 /* AsyncIterableSourceState.Initial */;
|
|
this._results = [];
|
|
this._error = null;
|
|
this._onReturn = onReturn;
|
|
this._onStateChanged = new Emitter();
|
|
queueMicrotask(async () => {
|
|
const writer = {
|
|
emitOne: (item) => this.emitOne(item),
|
|
emitMany: (items) => this.emitMany(items),
|
|
reject: (error) => this.reject(error)
|
|
};
|
|
try {
|
|
await Promise.resolve(executor(writer));
|
|
this.resolve();
|
|
}
|
|
catch (err) {
|
|
this.reject(err);
|
|
}
|
|
finally {
|
|
writer.emitOne = undefined;
|
|
writer.emitMany = undefined;
|
|
writer.reject = undefined;
|
|
}
|
|
});
|
|
}
|
|
[Symbol.asyncIterator]() {
|
|
let i = 0;
|
|
return {
|
|
next: async () => {
|
|
do {
|
|
if (this._state === 2 /* AsyncIterableSourceState.DoneError */) {
|
|
throw this._error;
|
|
}
|
|
if (i < this._results.length) {
|
|
return { done: false, value: this._results[i++] };
|
|
}
|
|
if (this._state === 1 /* AsyncIterableSourceState.DoneOK */) {
|
|
return { done: true, value: undefined };
|
|
}
|
|
await Event.toPromise(this._onStateChanged.event);
|
|
} while (true);
|
|
},
|
|
return: async () => {
|
|
this._onReturn?.();
|
|
return { done: true, value: undefined };
|
|
}
|
|
};
|
|
}
|
|
static map(iterable, mapFn) {
|
|
return new AsyncIterableObject(async (emitter) => {
|
|
for await (const item of iterable) {
|
|
emitter.emitOne(mapFn(item));
|
|
}
|
|
});
|
|
}
|
|
map(mapFn) {
|
|
return AsyncIterableObject.map(this, mapFn);
|
|
}
|
|
static filter(iterable, filterFn) {
|
|
return new AsyncIterableObject(async (emitter) => {
|
|
for await (const item of iterable) {
|
|
if (filterFn(item)) {
|
|
emitter.emitOne(item);
|
|
}
|
|
}
|
|
});
|
|
}
|
|
filter(filterFn) {
|
|
return AsyncIterableObject.filter(this, filterFn);
|
|
}
|
|
static coalesce(iterable) {
|
|
return AsyncIterableObject.filter(iterable, item => !!item);
|
|
}
|
|
coalesce() {
|
|
return AsyncIterableObject.coalesce(this);
|
|
}
|
|
static async toPromise(iterable) {
|
|
const result = [];
|
|
for await (const item of iterable) {
|
|
result.push(item);
|
|
}
|
|
return result;
|
|
}
|
|
toPromise() {
|
|
return AsyncIterableObject.toPromise(this);
|
|
}
|
|
/**
|
|
* The value will be appended at the end.
|
|
*
|
|
* **NOTE** If `resolve()` or `reject()` have already been called, this method has no effect.
|
|
*/
|
|
emitOne(value) {
|
|
if (this._state !== 0 /* AsyncIterableSourceState.Initial */) {
|
|
return;
|
|
}
|
|
// it is important to add new values at the end,
|
|
// as we may have iterators already running on the array
|
|
this._results.push(value);
|
|
this._onStateChanged.fire();
|
|
}
|
|
/**
|
|
* The values will be appended at the end.
|
|
*
|
|
* **NOTE** If `resolve()` or `reject()` have already been called, this method has no effect.
|
|
*/
|
|
emitMany(values) {
|
|
if (this._state !== 0 /* AsyncIterableSourceState.Initial */) {
|
|
return;
|
|
}
|
|
// it is important to add new values at the end,
|
|
// as we may have iterators already running on the array
|
|
this._results = this._results.concat(values);
|
|
this._onStateChanged.fire();
|
|
}
|
|
/**
|
|
* Calling `resolve()` will mark the result array as complete.
|
|
*
|
|
* **NOTE** `resolve()` must be called, otherwise all consumers of this iterable will hang indefinitely, similar to a non-resolved promise.
|
|
* **NOTE** If `resolve()` or `reject()` have already been called, this method has no effect.
|
|
*/
|
|
resolve() {
|
|
if (this._state !== 0 /* AsyncIterableSourceState.Initial */) {
|
|
return;
|
|
}
|
|
this._state = 1 /* AsyncIterableSourceState.DoneOK */;
|
|
this._onStateChanged.fire();
|
|
}
|
|
/**
|
|
* Writing an error will permanently invalidate this iterable.
|
|
* The current users will receive an error thrown, as will all future users.
|
|
*
|
|
* **NOTE** If `resolve()` or `reject()` have already been called, this method has no effect.
|
|
*/
|
|
reject(error) {
|
|
if (this._state !== 0 /* AsyncIterableSourceState.Initial */) {
|
|
return;
|
|
}
|
|
this._state = 2 /* AsyncIterableSourceState.DoneError */;
|
|
this._error = error;
|
|
this._onStateChanged.fire();
|
|
}
|
|
}
|
|
export class CancelableAsyncIterableObject extends AsyncIterableObject {
|
|
constructor(_source, executor) {
|
|
super(executor);
|
|
this._source = _source;
|
|
}
|
|
cancel() {
|
|
this._source.cancel();
|
|
}
|
|
}
|
|
export function createCancelableAsyncIterable(callback) {
|
|
const source = new CancellationTokenSource();
|
|
const innerIterable = callback(source.token);
|
|
return new CancelableAsyncIterableObject(source, async (emitter) => {
|
|
const subscription = source.token.onCancellationRequested(() => {
|
|
subscription.dispose();
|
|
source.dispose();
|
|
emitter.reject(new CancellationError());
|
|
});
|
|
try {
|
|
for await (const item of innerIterable) {
|
|
if (source.token.isCancellationRequested) {
|
|
// canceled in the meantime
|
|
return;
|
|
}
|
|
emitter.emitOne(item);
|
|
}
|
|
subscription.dispose();
|
|
source.dispose();
|
|
}
|
|
catch (err) {
|
|
subscription.dispose();
|
|
source.dispose();
|
|
emitter.reject(err);
|
|
}
|
|
});
|
|
}
|
|
//#endregion
|