From f96e1af33ef9e60434e07dc0fba5161f20b8eba6 Mon Sep 17 00:00:00 2001
From: Oliver Lazoroski <oliver.lazoroski@gmail.com>
Date: Thu, 5 Oct 2023 15:17:03 +0200
Subject: [PATCH] fix: ensure stable sort (#1130)

Ensure Stable Sorting by mutating the source participant array.
---
 packages/client/src/store/CallState.ts                | 5 +++--
 packages/client/src/store/__tests__/CallState.test.ts | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/packages/client/src/store/CallState.ts b/packages/client/src/store/CallState.ts
index e02f20919e..19d788488d 100644
--- a/packages/client/src/store/CallState.ts
+++ b/packages/client/src/store/CallState.ts
@@ -330,8 +330,9 @@ export class CallState {
   constructor() {
     this.logger = getLogger(['CallState']);
     this.participants$ = this.participantsSubject.asObservable().pipe(
-      // TODO: replace with Array.toSorted once available
-      map((ps) => [...ps].sort(this.sortParticipantsBy)),
+      // maintain stable-sort by mutating the participants stored
+      // in the original subject
+      map((ps) => ps.sort(this.sortParticipantsBy)),
       shareReplay({ bufferSize: 1, refCount: true }),
     );
 
diff --git a/packages/client/src/store/__tests__/CallState.test.ts b/packages/client/src/store/__tests__/CallState.test.ts
index 48e34c470a..59617990a4 100644
--- a/packages/client/src/store/__tests__/CallState.test.ts
+++ b/packages/client/src/store/__tests__/CallState.test.ts
@@ -69,7 +69,7 @@ describe('CallState', () => {
 
       const ps2 = state.participants;
       // should resolve in initial - non-mutated state as set at the beginning
-      expect(ps2.map((p) => p.name)).toEqual(['A', 'B', 'C', 'D', 'E', 'F']);
+      expect(ps2.map((p) => p.name)).toEqual(['F', 'B', 'E', 'A', 'C', 'D']);
     });
 
     it('should support custom sorting', () => {