From 0a2e8edf9720fa877648eed5cd2be73668897dc5 Mon Sep 17 00:00:00 2001
From: Hyunwoo Jung <chaosphch@gmail.com>
Date: Mon, 15 Jun 2026 14:12:19 +0900
Subject: [PATCH] fix(app): keep the unread session indicator stable during
 polling
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`buildSessionListViewData` bakes each row's `hasUnread` flag into a snapshot,
reading it from an *optional* `unreadSessionIds` set. `applySessions` passes
the set, but several other reducers rebuild the snapshot without it — most
importantly `applyMachines`, which fires on every machine heartbeat /
`fetchMachines` poll. On each such rebuild `hasUnread` falls back to
`undefined?.has(id) ?? false`, so every row loses its unread state until the
next `applySessions` restores it. The result is a distracting flicker of the
unread indicator (bold title on the bold-title builds, the status dot/text on
main) on the polling cadence, with no user action involved.

Make `unreadSessionIds` a required parameter on `buildSessionRowData` /
`buildSessionListViewData` so any reducer that forgets it is a compile error,
and thread `state.unreadSessionIds` through the call sites that dropped it
(`updateSessionDraft`, `applyMachines`, `deleteMachine`, `deleteSession`).

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>
---
 packages/happy-app/sources/sync/storage.ts | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/packages/happy-app/sources/sync/storage.ts b/packages/happy-app/sources/sync/storage.ts
index 42d554b6b1..be735d0056 100644
--- a/packages/happy-app/sources/sync/storage.ts
+++ b/packages/happy-app/sources/sync/storage.ts
@@ -95,7 +95,7 @@ export interface SessionRowData {
     hasUnread: boolean;
 }
 
-function buildSessionRowData(session: Session, unreadSessionIds?: Set<string>): SessionRowData {
+function buildSessionRowData(session: Session, unreadSessionIds: Set<string>): SessionRowData {
     const isOnline = session.presence === "online";
     const hasPermissions = !!(session.agentState?.requests && Object.keys(session.agentState.requests).length > 0);
 
@@ -125,7 +125,7 @@ function buildSessionRowData(session: Session, unreadSessionIds?: Set<string>):
         homeDir: session.metadata?.homeDir ?? null,
         completedTodosCount: session.todos?.filter(todo => todo.status === 'completed').length ?? 0,
         totalTodosCount: session.todos?.length ?? 0,
-        hasUnread: unreadSessionIds?.has(session.id) ?? false,
+        hasUnread: unreadSessionIds.has(session.id),
     };
 }
 
@@ -233,7 +233,7 @@ interface StorageState {
 // Helper function to build unified list view data from sessions and machines
 function buildSessionListViewData(
     sessions: Record<string, Session>,
-    unreadSessionIds?: Set<string>,
+    unreadSessionIds: Set<string>,
 ): SessionListViewItem[] {
     // Separate active and inactive sessions
     const activeSessions: Session[] = [];
@@ -1007,7 +1007,7 @@ export const storage = create<StorageState>()((set, get) => {
             return {
                 ...state,
                 sessions: updatedSessions,
-                sessionListViewData: buildSessionListViewData(updatedSessions)
+                sessionListViewData: buildSessionListViewData(updatedSessions, state.unreadSessionIds)
             };
         }),
         updateSessionPermissionMode: (sessionId: string, mode: string | null) => set((state) => {
@@ -1150,7 +1150,8 @@ export const storage = create<StorageState>()((set, get) => {
 
             // Rebuild sessionListViewData to reflect machine changes
             const sessionListViewData = buildSessionListViewData(
-                state.sessions
+                state.sessions,
+                state.unreadSessionIds,
             );
 
             return {
@@ -1167,7 +1168,7 @@ export const storage = create<StorageState>()((set, get) => {
             return {
                 ...state,
                 machines: remaining,
-                sessionListViewData: buildSessionListViewData(state.sessions)
+                sessionListViewData: buildSessionListViewData(state.sessions, state.unreadSessionIds)
             };
         }),
         // Artifact methods
@@ -1241,7 +1242,7 @@ export const storage = create<StorageState>()((set, get) => {
             saveSessionEffortLevels(effortLevels);
             
             // Rebuild sessionListViewData without the deleted session
-            const sessionListViewData = buildSessionListViewData(remainingSessions);
+            const sessionListViewData = buildSessionListViewData(remainingSessions, state.unreadSessionIds);
             
             return {
                 ...state,