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考虑以下代码在 Windows 上的 NodeJS 14.4 下运行：


const async_hooks = require('async_hooks');
const fs = require('fs');
const util = require('util');

let asyncLocalStorage = new async_hooks.AsyncLocalStorage();
asyncLocalStorage.enterWith({blah: 7});

function log(...args) {
  fs.writeSync(1, `${util.format(...args)}\n`);
}

function getCurrentId() {
  return async_hooks.executionAsyncId();
}

new Promise((res, rej) => {
    log(`first promise: ${getCurrentId()}`);
    res();
    log(`first promise done`);
}).then(() => {
    log(`second promise: ${getCurrentId()}`);
    asyncLocalStorage.enterWith({id: 7});
    log(`id in second promise=${asyncLocalStorage.getStore().id}`);
    log(`second promise done`);
}).then(() => {
    log(`third promise: ${getCurrentId()}`);
    log(`id in third promise=${asyncLocalStorage.getStore().id}`);
});

我预计第二个承诺的本地存储会传播到第三个承诺。但是，此代码的输出如下：

first promise: 1
first promise done
second promise: 3
id in second promise=7
second promise done
third promise: 4
id in third promise=undefined

如果我通过async-local-storage打开调试，则会显示以下输出：

2(PROMISE) init by 1
first promise: 1
first promise done
3(PROMISE) init by 2    <-- when first promise is done, context for the second promise is init'd
4(PROMISE) init by 3    <-- but context for third promise is also initiated, before the second promise even ran!
second promise: 3
id in second promise=7  <-- so the async store is set only after the context for the third promise is init'd
second promise done
third promise: 4
id in third promise=undefined  <-- which means AsyncLocalStorage did not copy the store to the third promise

我是否错过了期望商店也传播到第三个承诺的东西？

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