fetch: fix leak

Fixes: #1823

lib/fetch/request.js

@@ -34,6 +34,7 @@ const { setMaxListeners, getEventListeners, defaultMaxListeners } = require('eve
 let TransformStream = globalThis.TransformStream
 
 const kInit = Symbol('init')
+const kAbortController = Symbol('abortController')
 
 const requestFinalizer = new FinalizationRegistry(({ signal, abort }) => {
   signal.removeEventListener('abort', abort)
@@ -354,8 +355,14 @@ class Request {
       if (signal.aborted) {
         ac.abort(signal.reason)
       } else {
+        // Keep a strong ref to ac while request object
+        // is alive. This is needed to prevent AbortController
+        // from being prematurely garbage collected.
+        this[kAbortController] = ac
+
+        const weakAc = new WeakRef(ac)
         const abort = function () {
-          ac.abort(this.reason)
+          weakAc.deref()?.abort(this.reason)
         }
 
         // Third-party AbortControllers may not work with these.
@@ -367,7 +374,7 @@ class Request {
         } catch {}
 
         signal.addEventListener('abort', abort, { once: true })
-        requestFinalizer.register(this, { signal, abort })
+        requestFinalizer.register(ac, { signal, abort })
       }
     }