perf(renderer): index unread completion tabs (#17246)

src/renderer/src/components/tab-bar/terminal-tab-activity-status.test.ts

@@ -3,6 +3,7 @@ import type { AgentStatusEntry } from '../../../../shared/agent-status-types'
 import type { TerminalTab } from '../../../../shared/terminal-tab-types'
 import {
   hasUnreadAgentCompletionForTerminalTab,
+  resetUnreadAgentCompletionTabIdsCacheForTest,
   resetTerminalTabActivityFlagsCacheForTest,
   resolveTerminalTabActivityStatus,
   resolveTerminalTabAttentionBadge,
@@ -41,6 +42,7 @@ const LIVE_PTY = { [TAB_ID]: ['pty-1'] }
 
 beforeEach(() => {
   resetTerminalTabActivityFlagsCacheForTest()
+  resetUnreadAgentCompletionTabIdsCacheForTest()
   vi.useFakeTimers()
   vi.setSystemTime(NOW)
 })
@@ -48,6 +50,7 @@ beforeEach(() => {
 afterEach(() => {
   vi.useRealTimers()
   resetTerminalTabActivityFlagsCacheForTest()
+  resetUnreadAgentCompletionTabIdsCacheForTest()
 })
 
 describe('resolveTerminalTabActivityStatus', () => {
@@ -267,6 +270,7 @@ describe('hasUnreadAgentCompletionForTerminalTab', () => {
     expect(
       hasUnreadAgentCompletionForTerminalTab({ [`tab-2:${SECOND_LEAF_ID}`]: true }, TAB_ID)
     ).toBe(false)
+    expect(hasUnreadAgentCompletionForTerminalTab(undefined, TAB_ID)).toBe(false)
   })
 
   // Why: the param accepts boolean maps, so a cleared-to-`false` marker must not read as unread.
@@ -275,6 +279,57 @@ describe('hasUnreadAgentCompletionForTerminalTab', () => {
       hasUnreadAgentCompletionForTerminalTab({ [`${TAB_ID}:${FIRST_LEAF_ID}`]: false }, TAB_ID)
     ).toBe(false)
   })
+
+  it('preserves first-colon ownership for legacy and malformed pane keys', () => {
+    expect(hasUnreadAgentCompletionForTerminalTab({ [TAB_ID]: true }, TAB_ID)).toBe(true)
+    expect(hasUnreadAgentCompletionForTerminalTab({ [`${TAB_ID}:3`]: true }, TAB_ID)).toBe(true)
+    expect(
+      hasUnreadAgentCompletionForTerminalTab(
+        { [`${TAB_ID}:${FIRST_LEAF_ID}:suffix`]: true },
+        TAB_ID
+      )
+    ).toBe(true)
+    expect(
+      hasUnreadAgentCompletionForTerminalTab({ [`${TAB_ID}0:${SECOND_LEAF_ID}`]: true }, TAB_ID)
+    ).toBe(false)
+  })
+
+  it('changes only the owning tab when immutable marker snapshots add and clear unread', () => {
+    const before = { [`tab-2:${SECOND_LEAF_ID}`]: true }
+    const added = { ...before, [`${TAB_ID}:${FIRST_LEAF_ID}`]: true }
+    const cleared = { ...added, [`${TAB_ID}:${FIRST_LEAF_ID}`]: false }
+
+    expect(hasUnreadAgentCompletionForTerminalTab(before, TAB_ID)).toBe(false)
+    expect(hasUnreadAgentCompletionForTerminalTab(added, TAB_ID)).toBe(true)
+    expect(hasUnreadAgentCompletionForTerminalTab(cleared, TAB_ID)).toBe(false)
+    expect(hasUnreadAgentCompletionForTerminalTab(before, 'tab-2')).toBe(true)
+    expect(hasUnreadAgentCompletionForTerminalTab(added, 'tab-2')).toBe(true)
+    expect(hasUnreadAgentCompletionForTerminalTab(cleared, 'tab-2')).toBe(true)
+  })
+
+  it('indexes one immutable marker snapshot once across all mounted tab lookups', () => {
+    const ownKeys = vi.fn(Reflect.ownKeys)
+    let valueReads = 0
+    const markers: Record<string, true> = Object.fromEntries(
+      Array.from({ length: 1_000 }, (_, index) => [`owner-${index}:leaf`, true] as const)
+    )
+    const unread = new Proxy<Record<string, true>>(markers, {
+      ownKeys,
+      get: (target, property, receiver) => {
+        valueReads += 1
+        return Reflect.get(target, property, receiver)
+      }
+    })
+
+    for (let publication = 0; publication < 5; publication += 1) {
+      for (let tab = 0; tab < 500; tab += 1) {
+        expect(hasUnreadAgentCompletionForTerminalTab(unread, `absent-${tab}`)).toBe(false)
+      }
+    }
+
+    expect(ownKeys).toHaveBeenCalledTimes(1)
+    expect(valueReads).toBe(1_000)
+  })
 })
 
 describe('resolveTerminalTabAttentionBadge', () => {

src/renderer/src/components/tab-bar/terminal-tab-activity-status.ts

@@ -256,29 +256,49 @@ export function terminalTabHasUnreadActivity({
   )
 }
 
+// Why: production writes replace this map; WeakMap supports retained snapshots without pinning them.
+let unreadAgentCompletionTabIdsBySnapshot = new WeakMap<
+  Record<string, boolean | undefined>,
+  ReadonlySet<string>
+>()
+
+function getUnreadAgentCompletionTabIds(
+  unreadAgentCompletionPanes: Record<string, boolean | undefined>
+): ReadonlySet<string> {
+  const cached = unreadAgentCompletionTabIdsBySnapshot.get(unreadAgentCompletionPanes)
+  if (cached) {
+    return cached
+  }
+
+  // Why: every mounted tab runs this selector per store write; index each immutable marker snapshot once.
+  const tabIds = new Set<string>()
+  for (const paneKey of Object.keys(unreadAgentCompletionPanes)) {
+    if (!unreadAgentCompletionPanes[paneKey]) {
+      continue
+    }
+    const separatorIndex = paneKey.indexOf(':')
+    tabIds.add(separatorIndex === -1 ? paneKey : paneKey.slice(0, separatorIndex))
+  }
+  unreadAgentCompletionTabIdsBySnapshot.set(unreadAgentCompletionPanes, tabIds)
+  return tabIds
+}
+
 /** Match pane-level unread completion markers to their owning terminal tab. */
 export function hasUnreadAgentCompletionForTerminalTab(
   unreadAgentCompletionPanes: Record<string, boolean | undefined> | undefined,
   tabId: string
 ): boolean {
-  for (const [paneKey, unread] of Object.entries(unreadAgentCompletionPanes ?? {})) {
-    // Why entries, not keys: the widened value type lets a cleared marker linger as `false`.
-    if (!unread) {
-      continue
-    }
-    // paneKey is `${tabId}:${leafId}` and tab ids never contain ":", so the
-    // prefix up to the first ":" is the owning tab id (see
-    // selectFloatingWorkspaceHasUnread). Prefix-match to keep legacy keys.
-    const separatorIndex = paneKey.indexOf(':')
-    const owningTabId = separatorIndex === -1 ? paneKey : paneKey.slice(0, separatorIndex)
-    if (owningTabId === tabId) {
-      return true
-    }
-  }
-  return false
+  return unreadAgentCompletionPanes
+    ? getUnreadAgentCompletionTabIds(unreadAgentCompletionPanes).has(tabId)
+    : false
 }
 
 /** Test-only: clear the memoized per-tab flag cache between cases. */
 export function resetTerminalTabActivityFlagsCacheForTest(): void {
   flagsCache = null
 }
+
+/** Test-only: clear the unread marker snapshot index between cases. */
+export function resetUnreadAgentCompletionTabIdsCacheForTest(): void {
+  unreadAgentCompletionTabIdsBySnapshot = new WeakMap()
+}