fix: address Copilot review round 3 (code-point truncation, a11y live status, disabled-tab wait mirroring, test unmount, concurrent-wait test)

src/client/TerminalWaitBanner.tsx

@@ -12,16 +12,27 @@ import css from './sidebar.module.css'
 /** Cap the needle shown inline; the full text rides the title tooltip. */
 const NEEDLE_DISPLAY_CAP = 80
 
-/** Truncate one needle for inline display (title attr carries the full text). */
+/** Truncate one needle for inline display (title attr carries the full text).
+ *  Cut by Unicode code points, not UTF-16 code units — a naive slice can split
+ *  a surrogate pair at the cutoff and render a dangling replacement char. */
 export function truncateNeedle(needle: string): string {
-  return needle.length > NEEDLE_DISPLAY_CAP ? `${needle.slice(0, NEEDLE_DISPLAY_CAP - 1)}…` : needle
+  const points = Array.from(needle)
+  return points.length > NEEDLE_DISPLAY_CAP
+    ? `${points.slice(0, NEEDLE_DISPLAY_CAP - 1).join('')}…`
+    : needle
 }
 
 export function TerminalWaitBanner(props: { needle: string; onSkip: () => void }) {
   const { needle, onSkip } = props
   return (
     <div className={css.terminalWaitBanner}>
-      <span className={css.terminalWaitNeedle} title={needle}>
+      <span
+        className={css.terminalWaitNeedle}
+        title={needle}
+        role="status"
+        aria-live="polite"
+        aria-label={t('terminalWaitBanner', { needle })}
+      >
         {t('terminalWaitBanner', { needle: truncateNeedle(needle) })}
       </span>
       <button type="button" className={css.terminalRetry} onClick={onSkip}>

src/client/sidebar/use-host-feeds.ts

@@ -7,7 +7,7 @@
  */
 import { useEffect, useRef } from 'react'
 import type { Context, SidebarSessionList } from '../../context-types.ts'
-import { reconcileAgentTerminals, type SidebarStore } from '../state.ts'
+import { mirrorAgentWaits, reconcileAgentTerminals, type SidebarStore } from '../state.ts'
 import { detectNewDirectSubagent } from '../subagent-detect.ts'
 import { detectNewJob } from '../subagent-jobs.ts'
 import { t } from '../locales.ts'
@@ -65,7 +65,12 @@ export function useHostFeeds(feeds: {
           const list = JSON.parse(event.data) as Array<{ uuid: string; title: string; command: string; exited: boolean; waiting?: { needle: string; since: number } | null }>
           if (!Array.isArray(list)) return
           store.reduce(s => ctx.get('betterSidebar')?.isTabEnabled('terminal') === false
-            ? s
+            // Terminal tabs are disabled: skip tab add/remove reconciliation,
+            // but STILL mirror the authoritative wait map — a wait resolving
+            // during the disabled window must clear its banner state, or a
+            // re-enabled terminal keeps a stale banner until the next
+            // unrelated push.
+            ? mirrorAgentWaits(s, list)
             : reconcileAgentTerminals(s, list))
         } catch {
           // Malformed push: ignore (the next push will reconcile).

src/client/state.ts

@@ -687,6 +687,19 @@ function sameAgentWaits(
   return true
 }
 
+/** Fold the pushed terminal snapshots into the authoritative wait map. */
+function serverWaitsOf(
+  agentTerminals: ReadonlyArray<{ uuid: string; title: string; waiting?: { needle: string; since: number } | null }>,
+): Record<string, { needle: string; since: number }> {
+  const serverWaits: Record<string, { needle: string; since: number }> = {}
+  for (const terminal of agentTerminals) {
+    if (terminal.waiting !== undefined && terminal.waiting !== null) {
+      serverWaits[terminal.uuid] = { needle: terminal.waiting.needle, since: terminal.waiting.since }
+    }
+  }
+  return serverWaits
+}
+
 /**
  * Reconcile the sidebar's agent-terminal tabs with the host's live list.
  * The host pushes the current list of agent terminals (created by the model
@@ -719,12 +732,7 @@ export function reconcileAgentTerminals(
   // waiting field simply drops the entry). A waits-only change must still
   // produce a new state — the tab add/remove no-change check alone would
   // swallow banner updates.
-  const serverWaits: Record<string, { needle: string; since: number }> = {}
-  for (const terminal of agentTerminals) {
-    if (terminal.waiting !== undefined && terminal.waiting !== null) {
-      serverWaits[terminal.uuid] = { needle: terminal.waiting.needle, since: terminal.waiting.since }
-    }
-  }
+  const serverWaits = serverWaitsOf(agentTerminals)
   if (toAdd.length === 0 && toRemove.length === 0 && sameAgentWaits(state.agentWaits, serverWaits)) return state
   // Remove tabs whose uuids vanished from the server list (the agent closed
   // them, or the pty exited and was reaped). Reuse closeTab's leaf cleanup.
@@ -750,6 +758,23 @@ export function reconcileAgentTerminals(
   return { ...next, agentWaits: serverWaits }
 }
 
+/**
+ * Mirror ONLY the authoritative agent-wait map from a push — no tab
+ * add/remove reconciliation. Used while the `terminal` tab type is disabled:
+ * the tab surface is frozen, but a wait that resolves during that window
+ * must still clear its banner state, or a re-enabled terminal keeps a stale
+ * banner/⏳ until some unrelated host event fires the next full reconcile.
+ * Idempotent: a no-op when the map already matches.
+ */
+export function mirrorAgentWaits(
+  state: SidebarState,
+  agentTerminals: ReadonlyArray<{ uuid: string; title: string; waiting?: { needle: string; since: number } | null }>,
+): SidebarState {
+  const serverWaits = serverWaitsOf(agentTerminals)
+  if (sameAgentWaits(state.agentWaits, serverWaits)) return state
+  return { ...state, agentWaits: serverWaits }
+}
+
 // ── The per-session store ──────────────────────────────────────────────────
 
 const STORAGE_PREFIX = 'dsh-sidebar:v1'