fix #2044 - handle "isolated clients" errors (#2059)

Author: leibale

packages/client/lib/client/index.spec.ts

@@ -477,8 +477,11 @@ describe('Client', () => {
         assert.ok(id !== isolatedId);
     }, GLOBAL.SERVERS.OPEN);
 
-    async function killClient<M extends RedisModules, S extends RedisScripts>(client: RedisClientType<M, S>): Promise<void> {
-        const onceErrorPromise = once(client, 'error');
+    async function killClient<M extends RedisModules, S extends RedisScripts>(
+        client: RedisClientType<M, S>,
+        errorClient: RedisClientType<M, S> = client
+    ): Promise<void> {
+        const onceErrorPromise = once(errorClient, 'error');
         await client.sendCommand(['QUIT']);
         await Promise.all([
             onceErrorPromise,
@@ -503,6 +506,10 @@ describe('Client', () => {
         minimumDockerVersion: [6, 2] // CLIENT INFO
     });
 
+    testUtils.testWithClient('should propagated errors from "isolated" clients', client => {
+        return client.executeIsolated(isolated => killClient(isolated, client));
+    }, GLOBAL.SERVERS.OPEN);
+
     testUtils.testWithClient('scanIterator', async client => {
         const promises = [],
             keys = new Set();

packages/client/lib/client/index.ts

@@ -189,7 +189,7 @@ export default class RedisClient<M extends RedisModules, S extends RedisScripts>
             create: async () => {
                 const duplicate = this.duplicate({
                     isolationPoolOptions: undefined
-                });
+                }).on('error', err => this.emit('error', err));
                 await duplicate.connect();
                 return duplicate;
             },