From 602fcd23b4b39b3dba0d75af5ecb688a46b8c7a5 Mon Sep 17 00:00:00 2001
From: Michael Lumish <mlumish@google.com>
Date: Fri, 12 Mar 2021 09:39:50 -0800
Subject: [PATCH] grpc-js: Throw in watchConnectivityState if channel is closed

---
 packages/grpc-js/src/channel.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/packages/grpc-js/src/channel.ts b/packages/grpc-js/src/channel.ts
index 0f055d1e9..416aaa081 100644
--- a/packages/grpc-js/src/channel.ts
+++ b/packages/grpc-js/src/channel.ts
@@ -480,6 +480,9 @@ export class ChannelImplementation implements Channel {
     deadline: Date | number,
     callback: (error?: Error) => void
   ): void {
+    if (this.connectivityState === ConnectivityState.SHUTDOWN) {
+      throw new Error('Channel has been shut down');
+    }
     let timer = null;
     if(deadline !== Infinity) {
       const deadlineDate: Date =