From 785b987bd61e182fe659f7eefa1cc41ea5635d1b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 Oct 2022 12:33:53 -0400
Subject: [PATCH] fix: correct browser build and improve isAsyncFunction check
 for browser

Re: #12576
---
 lib/helpers/isAsyncFunction.js | 27 +++++++--------------------
 package.json                   |  3 ++-
 2 files changed, 9 insertions(+), 21 deletions(-)

diff --git a/lib/helpers/isAsyncFunction.js b/lib/helpers/isAsyncFunction.js
index 998705304a9..8210c0d1cfe 100644
--- a/lib/helpers/isAsyncFunction.js
+++ b/lib/helpers/isAsyncFunction.js
@@ -1,22 +1,9 @@
 'use strict';
 
-let asyncFunctionPrototype = null;
-// try/catch for Babel compatibility, because Babel preset-env requires
-// regenerator-runtime for async/await and we don't want to include that
-// for a simple check.
-try {
-  asyncFunctionPrototype = Object.getPrototypeOf(async function() {});
-} catch (err) {}
-
-if (asyncFunctionPrototype == null) {
-  module.exports = function isAsyncFunction() {
-    return false;
-  };
-} else {
-  module.exports = function isAsyncFunction(v) {
-    return (
-      typeof v === 'function' &&
-      Object.getPrototypeOf(v) === asyncFunctionPrototype
-    );
-  };
-}
+module.exports = function isAsyncFunction(v) {
+  return (
+    typeof v === 'function' &&
+    v.constructor &&
+    v.constructor.name === 'AsyncFunction'
+  );
+};
\ No newline at end of file
diff --git a/package.json b/package.json
index be779b793aa..7a37a154456 100644
--- a/package.json
+++ b/package.json
@@ -29,6 +29,7 @@
   },
   "devDependencies": {
     "@babel/core": "7.19.3",
+    "@babel/preset-env": "7.19.3",
     "@typescript-eslint/eslint-plugin": "5.38.1",
     "@typescript-eslint/parser": "5.38.1",
     "acquit": "1.2.1",
@@ -88,7 +89,7 @@
     "lint": "eslint .",
     "lint-js": "eslint . --ext .js",
     "lint-ts": "eslint . --ext .ts",
-    "build-browser": "node ./scripts/build-browser.js",
+    "build-browser": "(rm ./dist/* || true) && node ./scripts/build-browser.js",
     "prepublishOnly": "npm run build-browser",
     "release": "git pull && git push origin master --tags && npm publish",
     "release-legacy": "git pull origin 5.x && git push origin 5.x --tags && npm publish --tag legacy",