From: Jérôme Benoit <jerome.benoit@piment-noir.org>
Date: Wed, 16 Oct 2024 15:50:36 +0000 (+0200)
Subject: perf: speed up isAsyncFunction() helper
X-Git-Tag: v4.4.0~21
X-Git-Url: https://git.piment-noir.org/?a=commitdiff_plain;h=e155dc6f44e131201196c5537bff363d9d0b79bb;p=poolifier.git

perf: speed up isAsyncFunction() helper

Signed-off-by: Jérôme Benoit <jerome.benoit@piment-noir.org>
---

diff --git a/src/utils.ts b/src/utils.ts
index 0e1266a1..3e22b8c1 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -141,6 +141,8 @@ export const isKillBehavior = <KB extends KillBehavior>(
   return value === killBehavior
 }
 
+type AsyncFunctionType<A extends unknown[], R> = (...args: A) => PromiseLike<R>
+
 /**
  * Detects whether the given value is an asynchronous function or not.
  * @param fn - Unknown value.
@@ -149,8 +151,9 @@ export const isKillBehavior = <KB extends KillBehavior>(
  */
 export const isAsyncFunction = (
   fn: unknown
-): fn is (...args: unknown[]) => Promise<unknown> => {
-  return typeof fn === 'function' && fn.constructor.name === 'AsyncFunction'
+): fn is AsyncFunctionType<unknown[], unknown> => {
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  return fn?.constructor === (async () => {}).constructor
 }
 
 /**