mocha: beforeEach calls itself recursively (infinite loop) with karma

Prerequisites

• Checked that your issue hasn’t already been filed by cross-referencing issues with the faq label
• Checked next-gen ES issues and syntax problems by using the same environment and/or transpiler configuration without Mocha to ensure it isn’t just a feature that actually isn’t supported in the environment in question or a bug in your code.
• ‘Smoke tested’ the code to be tested by running it outside the real test suite to get a better sense of whether the problem is in the code under test, your usage of Mocha, or Mocha itself
• Ensured that there is no discrepancy between the locally and globally installed versions of Mocha. You can find them with: node node_modules/.bin/mocha --version(Local) and mocha --version(Global). We recommend that you not install Mocha globally.

Description

I am running mocha with karma for a while now without any issues. Upgrading to v9.0.0 (broken since 8.4) causes a stack overflow error whenever I run the suite. This happens in mocha.js in the global beforeEach function:

	  exports.beforeEach = function () {
	    for (var _len3 = arguments.length, args = new Array(_len3), _key3 = 0; _key3 < _len3; _key3++) {
	      args[_key3] = arguments[_key3];
	    }
	    return (currentContext.beforeEach || currentContext.setup).apply(this, args);
	  };

Where currentContext.beforeEach is set to:

function () {
        return mochaOriginal.beforeEach.apply(this, wrapTestInZone(arguments));
    }

Steps to Reproduce

• Open the repro
• npm i
• ng test

Expected behavior: Expects the tests to execute

Actual behavior: Stack overflow error

 ng test
⠋ Generating browser application bundles (phase: setup)...
START:
⠙ Generating browser application bundles (phase: building)...18 06 2021 10:39:57.276:INFO [karma-server]: Karma v6.3.4 server started at http://localhost:9876/
18 06 2021 10:39:57.279:INFO [launcher]: Launching browsers Chrome with concurrency unlimited
18 06 2021 10:39:57.289:INFO [launcher]: Starting browser Chrome
✔ Browser application bundle generation complete.
18 06 2021 10:40:01.513:INFO [Chrome 91.0.4472.106 (Windows 10)]: Connected on socket k1faU-y_JWVT_iH8AAAB with id 44573546
18 06 2021 10:40:03.165:WARN [web-server]: 404: /_karma_webpack_/base/node_modules/mocha/mocha.js.map
Chrome 91.0.4472.106 (Windows 10) ERROR
  Uncaught RangeError: Maximum call stack size exceeded
  at http://localhost:9876/_karma_webpack_/vendor.js:79921:27

  RangeError: Maximum call stack size exceeded
      at wrapTestInZone (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/fesm2015/zone-testing.js:1024:1)
      at global.beforeEach.global.setup.Mocha.beforeEach (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/fesm2015/zone-testing.js:1077:1)
      at exports.beforeEach (node_modules/mocha/mocha.js:28621:65)
      at global.beforeEach.global.setup.Mocha.beforeEach (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/fesm2015/zone-testing.js:1077:1)
      at exports.beforeEach (node_modules/mocha/mocha.js:28621:65)
      at global.beforeEach.global.setup.Mocha.beforeEach (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/fesm2015/zone-testing.js:1077:1)
      at exports.beforeEach (node_modules/mocha/mocha.js:28621:65)
      at global.beforeEach.global.setup.Mocha.beforeEach (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/fesm2015/zone-testing.js:1077:1)
      at exports.beforeEach (node_modules/mocha/mocha.js:28621:65)
      at global.beforeEach.global.setup.Mocha.beforeEach (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/fesm2015/zone-testing.js:1077:1)

Finished in 1.665 secs / 0 secs @ 10:40:03 GMT+1000 (Australian Eastern Standard Time)

SUMMARY:
√ 0 tests completed

Reproduces how often: 100%

Versions

• The output of mocha --version and node node_modules/.bin/mocha --version:
  • n/a
  • 9.0.0
• The output of node --version:
  • v14.15.5
• Your operating system
  • name and version: Windows 10
  • architecture (32 or 64-bit): 64
• Your shell (e.g., bash, zsh, PowerShell, cmd): bash
• Your browser and version (if running browser tests):
  • chrome 91.0.4472.106
• Any third-party Mocha-related modules (and their versions):
  • “karma”: “~6.3.3”,
  • “karma-chrome-launcher”: “~3.1.0”,
  • “karma-mocha”: “^2.0.1”,
  • “karma-mocha-reporter”: “^2.2.5”,
• Any code transpiler (e.g., TypeScript, CoffeeScript, Babel) being used (and its version):
  • Typescript 4.2.3

Additional Information

Downgrading to mocha 8.2 fixes the issue. (Also broken in 8.4). See attached for a minimal reproduction… reproduction.zip