From 0ef2a4d02c9350aff163df9cb61aece89c4dac0f Mon Sep 17 00:00:00 2001
From: Josh Field <joshfield999@gmail.com>
Date: Sun, 17 Oct 2021 08:58:55 +1100
Subject: [PATCH] fix: fix server attachment (#4127)

The check excluded an HTTPS server from being properly attached.

Related: https://github.com/socketio/socket.io/issues/4124
---
 lib/index.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/lib/index.ts b/lib/index.ts
index 5f9427c3c2..72c87ef677 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -156,9 +156,7 @@ export class Server<
     this.adapter(opts.adapter || Adapter);
     this.sockets = this.of("/");
     this.opts = opts;
-    if (srv instanceof http.Server || typeof srv === "number") {
-      this.attach(srv);
-    }
+    if (srv || typeof srv == "number") this.attach(srv as http.Server | number);
   }
 
   /**