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bmeck@Bradleys-MacBook-Pro promise-diagnostics-hook % sh ./cover.sh node ./test.mts
Unused Promise 64 (allocated 1 times):
  node:internal/deps/undici/undici:6402:24
  node:internal/deps/undici/undici:6:50
  node:internal/deps/undici/undici:8095:21
  node:internal/deps/undici/undici:6:50
  node:internal/deps/undici/undici:8548:18
  node:internal/deps/undici/undici:6:50
  node:internal/deps/undici/undici:8649:16
  node:internal/deps/undici/undici:6:50

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// LICENSE: MIT License
import {
  triggerAsyncId,
  createHook,
  executionAsyncId,
} from "node:async_hooks"
import fs from 'node:fs'
import { debug as createDebug } from "node:util"

let log_raw = new Set()

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import { createHook } from 'node:async_hooks';

let ticks = 0
const asyncHook = createHook({
  before() {
    ticks++
  },
});
asyncHook.enable();
let normal = Promise.resolve('cloud_secret');

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alert('GOOD')

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If you have ever had to deal with Promise heavy code, and in particular deep data structures you will likely be familiar with code like the following:

const body = await (await fetch(url)).json()

This has a LHS RHS interchange that causes non-linear edits while writing code (especially with autocomplete):

fetch(url) // LTR

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/// <reference types="node" />
// See NOTES below

import flatstr from 'flatstr'
import v8 from 'v8'

// @ts-check
class ArrayOfObjects {
  store = []
  constructor(count) {

bmeck

// node [--trace-gc] local-storage-exmaple.cjs
// creates a server
// will drop /favicon.ico connections poorly without properly closing them
//   `cleanupContext` AsyncLocalStorage + `cleanup` FinalizationRegistry will clean up
// will track the http request URL for errors in httpContext
//   will show up in error generated for bad permissions
// will grant permissions in permissionsContext based upon query params / search params
//   need ?fs=true to make / respond with a 200
//
// goto /?fs=true in browser to see it work

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// node [--trace-gc] local-storage-exmaple.cjs
// creates a server
// will drop /favicon.ico connections poorly without properly closing them
//   `cleanupContext` AsyncLocalStorage + `cleanup` FinalizationRegistry will clean up
// will track the http request URL for errors in httpContext
//   will show up in error generated for bad permissions
// will grant permissions in permissionsContext based upon query params / search params
//   need ?fs=true to make / respond with a 200
//
// goto /?fs=true in browser to see it work

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import util from 'util';
const promiseDebugging = util.debuglog('promises').enabled;
const danglingPromise = new FinalizationRegistry((stack) => {
  danglingStacks.delete(stack);
  console.log(stack);
});
const danglingStacks = new Set();
const stackCache = new WeakMap();
/**
 * @template T

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import * as ns from './index.js';
import {promisify} from 'util';
import {createReadStream, createWriteStream} from 'fs';
import {Session} from 'inspector';
import {PassThrough} from 'stream';
import {createHash} from 'crypto';

const session = new Session();
const stream = new PassThrough();