Node.js:Jest + redis.quit()但是打开句柄警告仍然存在

Question

我正在尝试使用redis和jest运行集成测试.

它始终抛出"Jest检测到以下1个打开的句柄可能使Jest退出:"与--detectOpenHandles一起运行时出错.

它没有挂起,因此套接字正在关闭,但是如何编写它以便它不会抛出该警告？

我的代码

import redis from 'redis';
let red: redis.RedisClient;

beforeAll(() => {
    red = redis.createClient();
});

afterAll((done) => {
    red.quit(() => {
        done();
    });
});

test('redis', (done) => {
    red.set('a', 'b', (err, data) => {
        console.log(err);
        red.get('a', (err, data) => {
            console.log(data);
            done();
        });
    });

});

警告

Jest has detected the following 1 open handle potentially keeping Jest from exiting:

?  TCPWRAP

    3 |
    4 | beforeAll(() => {
    > 5 |     red = redis.createClient();
        |                 ^
    6 | });
    7 |
    8 | afterAll((done) => {

    at RedisClient.Object.<anonymous>.RedisClient.create_stream (node_modules/redis/index.js:251:31)
    at new RedisClient (node_modules/redis/index.js:159:10)
    at Object.<anonymous>.exports.createClient (node_modules/redis/index.js:1089:12)
    at Object.<anonymous>.beforeAll (src/sockets/redis.integration.test.ts:5:17)

使用常规jest运行已编译的代码会引发相同的警告.编译后的代码几乎完全相同.

Answer 1

发帖后想通了。我忘了在这里发布答案。

它与如何redis.quit()处理其回调有关。

它创建了一个新线程，因此我们需要等待整个 eventloop 堆栈再次循环。请参阅下面的解决方法。

async function shutdown() {
    await new Promise((resolve) => {
        redis.quit(() => {
            resolve();
        });
    });
    // redis.quit() creates a thread to close the connection.
    // We wait until all threads have been run once to ensure the connection closes.
    await new Promise(resolve => setImmediate(resolve));
}