From aa6e3084647d57a0103ec2b8fe5525ec980d0002 Mon Sep 17 00:00:00 2001
From: George Fu <kuhe@users.noreply.github.com>
Date: Mon, 17 Jun 2024 15:45:05 +0000
Subject: [PATCH] fix(fetch-http-handler): move keepalive check to constructor
 (one-time)

---
 packages/fetch-http-handler/src/fetch-http-handler.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/packages/fetch-http-handler/src/fetch-http-handler.ts b/packages/fetch-http-handler/src/fetch-http-handler.ts
index 3d44b42ab4b..120976557fa 100644
--- a/packages/fetch-http-handler/src/fetch-http-handler.ts
+++ b/packages/fetch-http-handler/src/fetch-http-handler.ts
@@ -16,7 +16,7 @@ type FetchHttpHandlerConfig = FetchHttpHandlerOptions;
  * Detection of keepalive support. Can be overridden for testing.
  */
 export const keepAliveSupport = {
-  supported: Boolean(typeof Request !== "undefined" && "keepalive" in new Request("https://[::1]")),
+  supported: undefined,
 };
 
 /**
@@ -60,6 +60,11 @@ export class FetchHttpHandler implements HttpHandler<FetchHttpHandlerConfig> {
       this.config = options ?? {};
       this.configProvider = Promise.resolve(this.config);
     }
+    if (keepAliveSupport.supported === undefined) {
+      keepAliveSupport.supported = Boolean(
+        typeof Request !== "undefined" && "keepalive" in new Request("https://[::1]")
+      );
+    }
   }
 
   destroy(): void {