From 3e26b590588dc7e514062f350a012fade2d5fb71 Mon Sep 17 00:00:00 2001
From: Zack Sheppard <zack@zacksheppard.com>
Date: Fri, 27 Oct 2023 20:26:15 +0100
Subject: [PATCH 1/2] fix(@nestjs/event-emitter): Circumvent crash in
 reflect-metadata

This fixes #1008 by circumventing the situation where reflect-metadata
would be given a value that was neither a function nor an object because
the event-emitter was somehow tricked into traversing it as if it were.
E.G. by being given a Proxy wrapping and removing some keys of a class.
---
 lib/events-metadata.accessor.ts | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/lib/events-metadata.accessor.ts b/lib/events-metadata.accessor.ts
index 8275e59b..66269bb3 100644
--- a/lib/events-metadata.accessor.ts
+++ b/lib/events-metadata.accessor.ts
@@ -10,6 +10,15 @@ export class EventsMetadataAccessor {
   getEventHandlerMetadata(
     target: Type<unknown>,
   ): OnEventMetadata[] | undefined {
+    // Circumvent a crash that comes from reflect-metadata if it is
+    // given a non-object non-function target to reflect upon.
+    if (
+      target === undefined ||
+      (typeof target !== 'function' && typeof target !== 'object')
+    ) {
+      return undefined;
+    }
+
     const metadata = this.reflector.get(EVENT_LISTENER_METADATA, target);
     if (!metadata) {
       return undefined;

From 36d68f1663dcf43243dd28e0f865302b1bca69b1 Mon Sep 17 00:00:00 2001
From: Zack Sheppard <zack@zacksheppard.com>
Date: Fri, 27 Oct 2023 22:35:36 +0100
Subject: [PATCH 2/2] fix(@nestjs/event-emitter): Also capture the case where
 target is null

---
 lib/events-metadata.accessor.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/events-metadata.accessor.ts b/lib/events-metadata.accessor.ts
index 66269bb3..3d1b3f4b 100644
--- a/lib/events-metadata.accessor.ts
+++ b/lib/events-metadata.accessor.ts
@@ -13,7 +13,7 @@ export class EventsMetadataAccessor {
     // Circumvent a crash that comes from reflect-metadata if it is
     // given a non-object non-function target to reflect upon.
     if (
-      target === undefined ||
+      !target ||
       (typeof target !== 'function' && typeof target !== 'object')
     ) {
       return undefined;