2025-2-第一期

    function withResolvers() {
        let resolve, reject;
        const promise = new Promise((res, rej) => {
            resolve = res;
            reject = rej;
        });
        return { promise, resolve, reject };
    }

    const buildCancelableTask = (asyncFn) => {
        let rejected = false;
        const { promise, resolve, reject } = withResolvers();
        return {
            run: () => {
                if (!rejected) {
                    asyncFn().then(resolve, reject);
                }
                // 这里需要将withResolvers返回的Promise返回
                return promise;
            },

            cancel: () => {
                rejected = true;
                reject(new Error('CanceledError'));
            },
        };
    };
    // 创建一个task
    const task = buildCancelableTask(() => new Promise((res) => setTimeout(() => res('Task completed'), 3000)));
    task.run().then(console.log).catch(console.error);
    // 取消任务
    setTimeout(() => {
        task.cancel();
    }, 1000);

    const buildCancelableTask = (signal, asyncFunc) => {
        return new Promise((resolve, reject) => {
            asyncFunc().then(resolve).catch(reject);
            signal.addEventListener("abort", () => { reject("Task was canceled"); });
        });
    }
    const ac = new AbortController();
    const signal = ac.signal;
    const task = buildCancelableTask(signal, async () => {
    await new Promise((resolve) => setTimeout(resolve, 1000));
        console.log("Task completed");
    });
    ac.abort();