From 09fd6c303685b2a7c83b49df74e444b9fbd2844a Mon Sep 17 00:00:00 2001
From: Jordan Harband <ljharb@gmail.com>
Date: Wed, 22 Jan 2025 22:08:55 -0800
Subject: [PATCH] [Refactor] use `async-function` for the eval parts

Hopefully fixes #31.
---
 getAsyncFunc.d.ts |  5 -----
 getAsyncFunc.js   | 10 ----------
 index.d.ts        |  6 ++++--
 index.js          | 13 +++----------
 package.json      |  1 +
 5 files changed, 8 insertions(+), 27 deletions(-)
 delete mode 100644 getAsyncFunc.d.ts
 delete mode 100644 getAsyncFunc.js

diff --git a/getAsyncFunc.d.ts b/getAsyncFunc.d.ts
deleted file mode 100644
index 4095333..0000000
--- a/getAsyncFunc.d.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-import type { AsyncFunction } from '.';
-
-declare function getAsyncFunc(): AsyncFunction | false;
-
-export = getAsyncFunc;
\ No newline at end of file
diff --git a/getAsyncFunc.js b/getAsyncFunc.js
deleted file mode 100644
index f1a79c8..0000000
--- a/getAsyncFunc.js
+++ /dev/null
@@ -1,10 +0,0 @@
-'use strict';
-
-/** @type {import('./getAsyncFunc')} */
-module.exports = function () {
-	try {
-		return Function('return async function () {}')();
-	} catch (e) {
-		return false;
-	}
-};
diff --git a/index.d.ts b/index.d.ts
index 74949b0..515f3cb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,7 +1,9 @@
+import type { AsyncFunction } from 'async-function';
+
 declare namespace isAsyncFunction {
-    type AsyncFunction = (...args: any[]) => Promise<any>
+    export type { AsyncFunction };
 }
 
-declare function isAsyncFunction(fn: unknown): fn is isAsyncFunction.AsyncFunction;
+declare function isAsyncFunction(fn: unknown): fn is AsyncFunction;
 
 export = isAsyncFunction;
\ No newline at end of file
diff --git a/index.js b/index.js
index cb39b9f..cb39da5 100644
--- a/index.js
+++ b/index.js
@@ -10,10 +10,7 @@ var isFnRegex = safeRegexTest(/^\s*async(?:\s+function(?:\s+|\()|\s*\()/);
 var hasToStringTag = require('has-tostringtag/shams')();
 var getProto = require('get-proto');
 
-var getAsyncFunc = require('./getAsyncFunc');
-
-/** @type {import('.').AsyncFunction | false} */
-var AsyncFunction;
+var getAsyncFunc = require('async-function');
 
 /** @type {import('.')} */
 module.exports = function isAsyncFunction(fn) {
@@ -30,10 +27,6 @@ module.exports = function isAsyncFunction(fn) {
 	if (!getProto) {
 		return false;
 	}
-	if (typeof AsyncFunction === 'undefined') {
-		var asyncFunc = getAsyncFunc();
-		// eslint-disable-next-line no-extra-parens
-		AsyncFunction = asyncFunc ? /** @type {import('.').AsyncFunction} */ (getProto(asyncFunc)) : false;
-	}
-	return AsyncFunction && getProto(fn) === AsyncFunction;
+	var asyncFunc = getAsyncFunc();
+	return asyncFunc && asyncFunc.prototype === getProto(fn);
 };
diff --git a/package.json b/package.json
index ca547eb..401e7e0 100644
--- a/package.json
+++ b/package.json
@@ -45,6 +45,7 @@
 		"url": "https://github.com/inspect-js/is-async-function/issues"
 	},
 	"dependencies": {
+		"async-function": "^1.0.0",
 		"call-bound": "^1.0.3",
 		"get-proto": "^1.0.1",
 		"has-tostringtag": "^1.0.2",