fix: Revert breaking changes for detectOpenHandles

CHANGELOG.md

@@ -10,6 +10,7 @@
 - `[@jest/core]` [**BREAKING**] Group together open handles with the same stack trace ([#13417](https://github.com/jestjs/jest/pull/13417), & [#14543](https://github.com/jestjs/jest/pull/14543))
 - `[@jest/core]` Add `perfStats` to surface test setup overhead ([#14622](https://github.com/jestjs/jest/pull/14622))
 - `[@jest/core]` [**BREAKING**] Changed `--filter` to accept an object with shape `{ filtered: Array<string> }` to match [documentation](https://jestjs.io/docs/cli#--filterfile) ([#13319](https://github.com/jestjs/jest/pull/13319))
+- `[@jest/core]` [**BREAKING**] Revert breaking changes for `detectOpenHandles`. ([#14789](https://github.com/jestjs/jest/pull/14789))
 - `[@jest/core, @jest/test-sequencer]` [**BREAKING**] Exposes `globalConfig` & `contexts` to `TestSequencer` ([#14535](https://github.com/jestjs/jest/pull/14535), & [#14543](https://github.com/jestjs/jest/pull/14543))
 - `[jest-environment-jsdom]` [**BREAKING**] Upgrade JSDOM to v22 ([#13825](https://github.com/jestjs/jest/pull/13825))
 - `[@jest/environment-jsdom-abstract]` Introduce new package which abstracts over the `jsdom` environment, allowing usage of custom versions of JSDOM ([#14717](https://github.com/jestjs/jest/pull/14717))

e2e/__tests__/__snapshots__/detectOpenHandles.ts.snap

@@ -19,7 +19,7 @@ exports[`prints message about flag on slow tests with a custom timeout 1`] = `
 exports[`prints out info about open handlers 1`] = `
 "Jest has detected the following 1 open handle potentially keeping Jest from exiting:
 
-  ●  DNSCHANNEL,TCPSERVERWRAP
+  ●  TCPSERVERWRAP
 
       12 | const app = new Server();
       13 |

packages/jest-core/src/__tests__/collectHandles.test.js

@@ -32,10 +32,8 @@ describe('collectHandles', () => {
   it('should not collect the PerformanceObserver open handle', async () => {
     const handleCollector = collectHandles();
 
-    let obs = new PerformanceObserver((list, observer) => {});
+    const obs = new PerformanceObserver((list, observer) => {});
     obs.observe({entryTypes: ['mark']});
-    obs.disconnect();
-    obs = null;
 
     const openHandles = await handleCollector();
 
@@ -47,12 +45,9 @@ describe('collectHandles', () => {
   it('should not collect the DNSCHANNEL open handle', async () => {
     const handleCollector = collectHandles();
 
-    let resolver = new dns.Resolver();
+    const resolver = new dns.Resolver();
     resolver.getServers();
 
-    // We must drop references to it
-    resolver = null;
-
     const openHandles = await handleCollector();
 
     expect(openHandles).not.toContainEqual(
@@ -141,11 +136,10 @@ describe('collectHandles', () => {
     );
   });
 
-  it('should not be false positives for some special objects such as `TLSWRAP`', async () => {
+  it('should not collect the `TLSWRAP` open handle', async () => {
     const handleCollector = collectHandles();
 
     const socket = new TLSSocket();
-    socket.destroy();
 
     const openHandles = await handleCollector();
 

packages/jest-core/src/collectHandles.ts

@@ -9,8 +9,7 @@
 
 import * as asyncHooks from 'async_hooks';
 import {promisify} from 'util';
-import * as v8 from 'v8';
-import * as vm from 'vm';
+import {getHeapSnapshot} from 'v8';
 import stripAnsi = require('strip-ansi');
 import type {Config} from '@jest/types';
 import {formatExecError} from 'jest-message-util';
@@ -46,20 +45,9 @@ const hasWeakRef = typeof WeakRef === 'function';
 
 const asyncSleep = promisify(setTimeout);
 
-let gcFunc: (() => void) | undefined = (globalThis as any).gc;
 function runGC() {
-  if (!gcFunc) {
-    v8.setFlagsFromString('--expose-gc');
-    gcFunc = vm.runInNewContext('gc');
-    v8.setFlagsFromString('--no-expose-gc');
-    if (!gcFunc) {
-      throw new Error(
-        'Cannot find `global.gc` function. Please run node with `--expose-gc` and report this issue in jest repo.',
-      );
-    }
-  }
-
-  gcFunc();
+  // It is more aggressive than `gc()`.
+  getHeapSnapshot();
 }
 
 // Inspired by https://github.com/mafintosh/why-is-node-running/blob/master/index.js
@@ -82,7 +70,20 @@ export default function collectHandles(): HandleCollectionResult {
       // Skip resources that should not generally prevent the process from
       // exiting, not last a meaningfully long time, or otherwise shouldn't be
       // tracked.
-      if (type === 'PROMISE') {
+      if (
+        [
+          'PROMISE',
+          'TIMERWRAP',
+          'ELDHISTOGRAM',
+          'PerformanceObserver',
+          'RANDOMBYTESREQUEST',
+          'DNSCHANNEL',
+          'ZLIB',
+          'SIGNREQUEST',
+          'TLSWRAP',
+          'TCPWRAP',
+        ].includes(type)
+      ) {
         return;
       }
       const error = new ErrorWithStack(type, initHook, 100);
@@ -136,8 +137,6 @@ export default function collectHandles(): HandleCollectionResult {
       await asyncSleep(30);
 
       if (activeHandles.size > 0) {
-        // For some special objects such as `TLSWRAP`.
-        // Ref: https://github.com/jestjs/jest/issues/11665
         runGC();
 
         await asyncSleep(0);