parallel-universe/AbortablePromise.js

The set of async flow control structures and promise utils.

'use strict';

/**
 * The promise that can be aborted.
 *
 * @template T The value that the promise is resolved with.
 */
class AbortablePromise extends Promise {
    static get [Symbol.species]() {
        return Promise;
    }
    /**
     * Creates a new abortable promise.
     *
     * @param executor A callback that initializes the promise.
     * @template T The value that the promise is resolved with.
     */
    constructor(executor) {
        const abortController = new AbortController();
        super((resolve, reject) => {
            abortController.signal.addEventListener('abort', () => {
                reject(abortController.signal.reason);
            });
            executor(resolve, reject, abortController.signal);
        });
        this._abortController = abortController;
    }
    /**
     * Aborts the signal passed to the executor and instantly rejects the promise with the reason.
     *
     * @param reason The abort reason. If not explicitly provided, it defaults to an
     * {@link https://developer.mozilla.org/en-US/docs/Web/API/DOMException#aborterror AbortError}.
     */
    abort(reason) {
        this._abortController.abort(reason);
    }
    /**
     * Subscribes this promise to be aborted when the signal is aborted.
     *
     * @param signal The signal that aborts this promise.
     * @returns This promise.
     */
    withSignal(signal) {
        if (signal.aborted) {
            this.abort(signal.reason);
        }
        else {
            signal.addEventListener('abort', () => {
                this.abort(signal.reason);
            });
        }
        return this;
    }
}

exports.AbortablePromise = AbortablePromise;