Discriminator in username

ts/util/sleep.ts

@@ -1,8 +1,16 @@
 // Copyright 2020 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
-export function sleep(ms: number): Promise<void> {
-  return new Promise(resolve => {
-    setTimeout(resolve, ms);
+export function sleep(ms: number, abortSignal?: AbortSignal): Promise<void> {
+  return new Promise((resolve, reject) => {
+    let timeout: NodeJS.Timeout | undefined = setTimeout(resolve, ms);
+
+    abortSignal?.addEventListener('abort', () => {
+      if (timeout !== undefined) {
+        clearTimeout(timeout);
+        timeout = undefined;
+      }
+      reject(new Error('Aborted'));
+    });
   });
 }