some refs...

Author: mydea

packages/browser/src/integrations/browserapierrors.ts

@@ -172,18 +172,16 @@ function _wrapEventTarget(target: string): void {
   }
 
   fill(proto, 'addEventListener', function (original: VoidFunction,): (
-    eventName: string,
-    fn: EventListenerObject,
-    options?: boolean | AddEventListenerOptions,
+    ...args: Parameters<typeof WINDOW.addEventListener>
   ) => void {
     return function (
       this: unknown,
-      eventName: string,
-      fn: EventListenerObject,
-      options?: boolean | AddEventListenerOptions,
+      eventName,
+      fn,
+      options,
     ): (eventName: string, fn: EventListenerObject, capture?: boolean, secure?: boolean) => void {
       try {
-        if (typeof fn.handleEvent === 'function') {
+        if (isEventListenerObject(fn)) {
           // ESlint disable explanation:
           //  First, it is generally safe to call `wrap` with an unbound function. Furthermore, using `.bind()` would
           //  introduce a bug here, because bind returns a new function that doesn't have our
@@ -202,7 +200,7 @@ function _wrapEventTarget(target: string): void {
             },
           });
         }
-      } catch (err) {
+      } catch {
         // can sometimes get 'Permission denied to access property "handle Event'
       }
 
@@ -226,16 +224,9 @@ function _wrapEventTarget(target: string): void {
 
   fill(proto, 'removeEventListener', function (originalRemoveEventListener: () => void,): (
     this: unknown,
-    eventName: string,
-    fn: EventListenerObject,
-    options?: boolean | EventListenerOptions,
+    ...args: Parameters<typeof WINDOW.removeEventListener>
   ) => () => void {
-    return function (
-      this: unknown,
-      eventName: string,
-      fn: EventListenerObject,
-      options?: boolean | EventListenerOptions,
-    ): () => void {
+    return function (this: unknown, eventName, fn, options): () => void {
       /**
        * There are 2 possible scenarios here:
        *
@@ -253,16 +244,19 @@ function _wrapEventTarget(target: string): void {
        * then we have to detach both of them. Otherwise, if we'd detach only wrapped one, it'd be impossible
        * to get rid of the initial handler and it'd stick there forever.
        */
-      const wrappedEventHandler = fn as unknown as WrappedFunction;
       try {
-        const originalEventHandler = wrappedEventHandler && wrappedEventHandler.__sentry_wrapped__;
+        const originalEventHandler = (fn as WrappedFunction).__sentry_wrapped__;
         if (originalEventHandler) {
           originalRemoveEventListener.call(this, eventName, originalEventHandler, options);
         }
       } catch (e) {
         // ignore, accessing __sentry_wrapped__ will throw in some Selenium environments
       }
-      return originalRemoveEventListener.call(this, eventName, wrappedEventHandler, options);
+      return originalRemoveEventListener.call(this, eventName, fn, options);
     };
   });
 }
+
+function isEventListenerObject(obj: unknown): obj is EventListenerObject {
+  return typeof (obj as EventListenerObject).handleEvent === 'function';
+}