feat(ui-workspace): fold sidebar sessions with a monotonic watermark

Each Workspace shows a contiguous prefix of its Sessions up to a watermark. The watermark rises to cover running, waiting, unread-completion, and current Sessions within the first 50 rows, and to a search reveal target at any row. It never falls on its own; Show more raises it past 50, and Show less or folding (including an ancestor) resets it.
2026-10-12 20:36:18 +08:00
1 parent 3a7e896206
commit 7df3c41ec9
@@ -15,8 +15,8 @@
  en: d152484eb41ac6b4
  zh: 09388d293f9be9cb
 /deepseek-ai-dsh-client-ui-workspace/use-this-package:
-  en: b164014ee565be16
-  zh: 6a741647932b93e6
+  en: d51507f87484f818
+  zh: e2600daa21e35f36
 /deepseek-ai-dsh-client-ui-workspace/use-this-package/reordering-and-view-options:
  en: 8673afc1d72ad077
  zh: 9fbb83a4029c5d10
@@ -27,7 +27,7 @@ This package lets users browse grouped or flat Session lists, choose a Workspace
 <a id="use-this-package"></a>
 ## Use this package

-Use the sidebar to browse Workspaces and their Sessions, reorder them, and start new ones; use the picker in the Session Intent hero to choose a Workspace for a new session. An open Workspace shows five idle, non-blank Sessions by default. Running Sessions, including parents with running children, remain visible in their ordered positions without using that quota; the selected blank **New Session** is also an extra row until its first prompt. Each **Show more** click reveals up to five more idle Sessions; after the final batch, **Show less** restores the initial rows while keeping running Sessions visible. Closing and reopening the Workspace also restores this folded projection.
+Use the sidebar to browse Workspaces and their Sessions, reorder them, and start new ones; use the picker in the Session Intent hero to choose a Workspace for a new session. An open Workspace shows its first non-blank Sessions in list order up to a per-Workspace watermark, initially five. The watermark rises to cover the last Session within the first 50 that is running, has a running child, awaits the user, has an unread completion, or is open in the main view; a Session opened from search raises it to that Session at any position. The watermark never falls on its own, so a Session stays visible after its run or notification ends. Each **Show more** click raises it by five, without the 50-row limit, and reveals the rest when five or fewer remain; after the final batch, **Show less** resets it. Folding a Workspace resets its watermark and those of its nested Workspaces; a reset watermark still covers the qualifying Sessions. The selected blank **New Session** is an extra row outside the watermark until its first prompt. Watermarks are not persisted; they reset when the grouped tree unmounts, including reloads, flat grouping, and search results.

 History rows without a stored title use the localized unnamed label (未命名 / Untitled), rather than a directory name. The current blank row remains New Session; other blank rows remain hidden. Rename drafts use the stored title, or start empty when unnamed; unnamed rows do not offer title copying.

@@ -27,7 +27,7 @@ kind: "package-reference"
 <a id="use-this-package"></a>
 ## 使用本包

-用侧边栏浏览 Workspace 及其 Session、重排它们并新建会话；在 Session Intent 主视觉区用选择器为新会话选择 Workspace。打开的 Workspace 默认显示五条空闲的非空白 Session。正在运行的 Session（包括有子会话正在运行的父会话）始终按原顺序显示，不占用这五条配额；当前选中的空白**新会话**在首条提示词落地前也作为额外行。每次点击**展开其余**最多再显示五条空闲 Session；全部显示后，**收起**恢复初始行数，但仍显示正在运行的 Session。关闭再打开 Workspace 也会恢复该折叠投影。
+用侧边栏浏览 Workspace 及其 Session、重排它们并新建会话；在 Session Intent 主视觉区用选择器为新会话选择 Workspace。打开的 Workspace 按列表顺序显示前面的非空白 Session，直到该 Workspace 自己的水位线，水位线初始为五。水位线会升高，以覆盖前 50 条中最后一条正在运行、有子会话正在运行、等待用户、有未读完成提醒或在主视图中打开的 Session；从搜索打开的 Session 会把水位线升高到该 Session，无论其位置。水位线不会自行回落，因此 Session 在运行或通知结束后仍保持可见。每次点击**展开其余**将水位线升高五条，不受 50 行限制；剩余五条或更少时显示全部；最后一批显示后，**收起**重置水位线。折叠 Workspace 会重置其水位线及其嵌套 Workspace 的水位线；重置后的水位线仍覆盖符合条件的 Session。当前选中的空白**新会话**在首条提示词落地前是水位线之外的额外行。水位线不持久化；分组树卸载时会重置，包括重新加载、切换到平铺分组和显示搜索结果时。

 未保存标题的历史会话显示本地化名称「未命名 / Untitled」，不使用目录名兜底。当前空会话仍显示「新会话」，其他空会话仍隐藏。重命名草稿使用已保存标题，无标题时留空；无标题行不提供标题复制。

@@ -51,24 +51,60 @@ const EXPAND_SLIDE_MS = 300
 const SEARCH_DEBOUNCE_MS = 250
 /** `session.search` wire bound, measured in JavaScript UTF-16 code units. */
 const SEARCH_QUERY_MAX_CODE_UNITS = 500
-/** Idle Session rows visible per Workspace before the local overflow control. */
-const COLLAPSED_SESSION_LIMIT = 5
+/** Non-blank Session rows visible per Workspace while no Session raises its watermark. */
+const SESSION_WATERMARK_BASE = 5
+/** Highest watermark that attention-bearing Sessions raise automatically; Show more and search reveals may exceed it. */
+const SESSION_WATERMARK_AUTO_MAX = 50

-/** Keep provisional and running rows outside the idle-session quota, including parents with running children. */
-function collapsedSessionRows(sessions: readonly SessionNode[], limit = COLLAPSED_SESSION_LIMIT): {
+/** Show the blank row plus the first `watermark` non-blank rows, in list order. */
+function watermarkRows(sessions: readonly SessionNode[], watermark: number): {
  rows: readonly SessionNode[]
  hiddenCount: number
 } {
-  let idleCount = 0
+  let count = 0
  const rows = sessions.filter((session) => {
-    if (session.blank || session.running || session.runningSubagentCount > 0) return true
-    if (idleCount >= limit) return false
-    idleCount += 1
-    return true
+    if (session.blank) return true
+    count += 1
+    return count <= watermark
  })
  return { rows, hiddenCount: sessions.length - rows.length }
 }

+/**
+ * Smallest watermark that covers every non-blank row within the automatic maximum that is running, has a running
+ * child, awaits the user, carries an unread completion, or is current, and the reveal target at any position.
+ */
+function requiredWatermark(
+  sessions: readonly SessionNode[],
+  current: SessionId | undefined,
+  revealSessionId: SessionId | undefined,
+): number {
+  let index = 0
+  let required = 0
+  for (const session of sessions) {
+    if (session.blank) continue
+    index += 1
+    const attention = index <= SESSION_WATERMARK_AUTO_MAX && (
+      session.running || session.runningSubagentCount > 0 || session.pendingInteraction !== undefined
+      || session.completed || session.id === current
+    )
+    if (attention || session.id === revealSessionId) required = index
+  }
+  return required
+}
+
+/** Raise each listed group's watermark to its requirement; returns `marks` itself when nothing rises. */
+function raiseWatermarks(
+  marks: Readonly<Record<string, number>>,
+  required: ReadonlyMap<string, number>,
+): Readonly<Record<string, number>> {
+  let raised = marks
+  for (const [key, watermark] of required) {
+    if (watermark > (raised[key] ?? SESSION_WATERMARK_BASE)) raised = { ...raised, [key]: watermark }
+  }
+  return raised
+}
+
 /** Keep controlled input and RPC payload inside the session.search wire contract. */
 function sanitizeSearchQuery(value: string): string {
  const withoutNul = value.replaceAll('\0', '')
@@ -277,7 +313,7 @@ function EmptySessions({ rowState, onLeaveArchivedOnly, t }: Pick<SessionTreePro
  )
 }

-/** The scrolling session tree; unmounting drops the sessions subscription and local row limits. */
+/** The scrolling session tree; unmounting drops the sessions subscription and the session watermarks. */
 function SessionTree({
  list, useSessionStatus, startSession, open, workspaces, ungroupedSessionIds,
  rowState, onLeaveArchivedOnly,
@@ -297,7 +333,10 @@ function SessionTree({
  const revealGroup = revealSessionId === undefined || !workspaceReady
    ? undefined
    : owningGroupKey(workspaces, revealSessionId)
-  const [sessionLimits, setSessionLimits] = useState<Readonly<Record<string, number>>>({})
+  // Per-group raised watermarks; an absent key means the base watermark.
+  const [storedWatermarks, setStoredWatermarks] = useState<Readonly<Record<string, number>>>({})
+  // Advances on user-driven watermark changes so AnimatedRows settles them; automatic raises animate.
+  const [watermarkMotionKey, setWatermarkMotionKey] = useState(0)
  // Transient drag marker state; the selected mode owns the resulting order.
  const [drag, setDrag] = useState<DragState | null>(null)
  const sessionDropCommitted = useRef(false)
@@ -347,13 +386,35 @@ function SessionTree({
      }
    }
  }, [groupExpansion, parents, revealGroup, setGroupExpanded])
-  useEffect(() => {
-    if (revealSessionId === undefined || revealGroup === undefined) return
-    const group = groups.find(candidate => candidate.key === revealGroup)
-    if (group === undefined || !group.expanded || !group.sessions.some(row => row.id === revealSessionId)) return
-    if (collapsedSessionRows(group.sessions).rows.some(row => row.id === revealSessionId)) return
-    setSessionLimits(limits => limits[revealGroup] === Infinity ? limits : { ...limits, [revealGroup]: Infinity })
-  }, [groups, revealGroup, revealSessionId])
+  const baselineWatermark = (group: GroupNode): number => Math.max(SESSION_WATERMARK_BASE, requiredWatermark(
+    group.sessions,
+    current,
+    group.key === revealGroup ? revealSessionId : undefined,
+  ))
+  const foldedKeys = new Set(groups.filter(group => !group.expanded).map(group => group.key))
+  const underFoldedAncestor = (key: string): boolean => {
+    for (let owner = parents.get(key); owner !== undefined; owner = parents.get(owner)) {
+      if (foldedKeys.has(owner)) return true
+    }
+    return false
+  }
+  // A group hidden by a folded ancestor keeps its own expansion and rows but must not raise its watermark.
+  const requiredWatermarks = new Map(groups
+    .filter(group => !underFoldedAncestor(group.key))
+    .map(group => [group.key, baselineWatermark(group)]))
+  const sessionWatermarks = raiseWatermarks(storedWatermarks, requiredWatermarks)
+  // Raising during render keeps the watermark monotonic without committing a lower frame first.
+  if (sessionWatermarks !== storedWatermarks) setStoredWatermarks(marks => raiseWatermarks(marks, requiredWatermarks))
+  const dropWatermarks = (drop: (key: string) => boolean): void => {
+    setStoredWatermarks(marks => Object.fromEntries(Object.entries(marks).filter(([key]) => !drop(key))))
+    setWatermarkMotionKey(key => key + 1)
+  }
+  const withinGroup = (key: string, root: string): boolean => {
+    for (let owner: string | undefined = key; owner !== undefined; owner = parents.get(owner)) {
+      if (owner === root) return true
+    }
+    return false
+  }
  const now = Date.now()
  const commitSessionDrag = (activeDrag: DragState, over: NonNullable<DragState['over']>): void => {
    if (sessionDropCommitted.current) return
@@ -366,7 +427,7 @@ function SessionTree({
      ? ungroupedSessionIds
      : workspaces.find(workspace => workspace.workspaceId === activeDrag.accountKey)?.sessionIds
    if (accountSessionIds === undefined) return
-    const renderedSessions = collapsedSessionRows(group.sessions, sessionLimits[group.key]).rows
+    const renderedSessions = watermarkRows(group.sessions, sessionWatermarks[group.key] ?? SESSION_WATERMARK_BASE).rows
    const nextOrder = sessionDragOrder(accountSessionIds, renderedSessions, activeDrag, over)
    if (nextOrder !== undefined) setSessionOrder(activeDrag.accountKey, nextOrder)
  }
@@ -416,8 +477,9 @@ function SessionTree({
    const workspaceId = group.workspaceId
    const children = childrenByParent.get(group.key) ?? []
    const compatibleDrag = workspaceDrag !== null && parents.get(workspaceDrag.workspaceId) === parents.get(group.key)
-    const collapsed = collapsedSessionRows(group.sessions)
-    const visible = collapsedSessionRows(group.sessions, sessionLimits[group.key])
+    const watermark = sessionWatermarks[group.key] ?? SESSION_WATERMARK_BASE
+    const collapsed = watermarkRows(group.sessions, baselineWatermark(group))
+    const visible = watermarkRows(group.sessions, watermark)
    const sessionsExpanded = visible.hiddenCount === 0
    rowKeys.push(`workspace:${group.key}`)
    const childRows = group.expanded ? children.map(child => renderGroup(child, depth + 1)) : []
@@ -500,9 +562,7 @@ function SessionTree({
          home={home}
          t={t}
          onToggle={() => {
-            if (group.expanded) {
-              setSessionLimits(limits => ({ ...limits, [group.key]: COLLAPSED_SESSION_LIMIT }))
-            }
+            if (group.expanded) dropWatermarks(key => withinGroup(key, group.key))
            setGroupExpanded(group.key, !group.expanded)
          }}
          onCreate={() => {
@@ -585,14 +645,15 @@ function SessionTree({
            data-row-key={`overflow:${group.key}`}
            aria-expanded={sessionsExpanded}
            onClick={() => {
-              setSessionLimits(limits => ({
-                ...limits,
-                [group.key]: sessionsExpanded
-                  ? COLLAPSED_SESSION_LIMIT
-                  : visible.hiddenCount <= COLLAPSED_SESSION_LIMIT
-                    ? Infinity
-                    : (limits[group.key] ?? COLLAPSED_SESSION_LIMIT) + COLLAPSED_SESSION_LIMIT,
+              if (sessionsExpanded) {
+                dropWatermarks(key => key === group.key)
+                return
+              }
+              setStoredWatermarks(marks => ({
+                ...marks,
+                [group.key]: visible.hiddenCount <= SESSION_WATERMARK_BASE ? Infinity : watermark + SESSION_WATERMARK_BASE,
              }))
+              setWatermarkMotionKey(key => key + 1)
            }}
          >
            {sessionsExpanded
@@ -613,7 +674,7 @@ function SessionTree({
        label={t('section.sessions')}
        rowKeys={rowKeys}
        ready={list.phase === 'ready' && workspaceReady && !nativeDragActive}
-        resetKey={JSON.stringify([animationResetKey, sessionLimits])}
+        resetKey={JSON.stringify([animationResetKey, watermarkMotionKey])}
      >
        {groups.length === 0 && (
          <EmptySessions rowState={rowState} onLeaveArchivedOnly={onLeaveArchivedOnly} t={t} />
@@ -7,7 +7,9 @@ import type { SessionListState, SessionSummary } from '@deepseek-ai/dsh-api-sess
 import type {
  WorkspaceId, WorkspaceSnapshot, WorkspaceView,
 } from '@deepseek-ai/dsh-api-workspace-controller/client'
-import type { SessionStatusSnapshot } from '@deepseek-ai/dsh-client-ui-session/client'
+import type {
+  SessionPendingInteraction, SessionStatus, SessionStatusSnapshot,
+} from '@deepseek-ai/dsh-client-ui-session/client'
 import type { SessionId } from '@deepseek-ai/dsh-session/types'
 import type { MainPanelId } from '@deepseek-ai/dsh-client-ui-layout/client'
 import { zh as commonZh } from '@deepseek-ai/dsh-client-locale/src/locales/zh.ts'
@@ -770,63 +772,80 @@ describe('WorkspaceBrowser', () => {
    expect(screen.getByRole('button', { name: '展开其余 2 个会话' })).toBeTruthy()
  })

-  it('keeps running sessions outside every batch quota and preserves their order after collapse', () => {
-    const idle = Array.from({ length: 12 }, (_, index) => summary(`idle-${index + 1}`, 12 - index))
-    const first = summary('running-first', 14, { running: true })
-    const last = summary('running-last', 0, { running: true })
-    const blank = summary('blank', 15, { blank: true })
-    const items = [blank, first, ...idle, last]
-    mount({
-      useSessions: hook(sessionState(items, { main: blank.id })),
-      useWorkspaces: hook(workspaceState([workspace('alpha', items.map(item => item.id))])),
-    })
-    const expectRows = (count: number) => {
-      expect(screen.getAllByRole('treeitem').map(row =>
-        within(row).getByText(/^(alpha|新会话|running-(first|last)|idle-\d+)$/u).textContent)).toEqual([
-        'alpha', '新会话', 'running-first', ...idle.slice(0, count).map(item => item.displayTitle), 'running-last',
-      ])
-    }
-    expectRows(5)
-    fireEvent.click(screen.getByRole('button', { name: '展开其余 7 个会话' }))
-    expectRows(10)
-    fireEvent.click(screen.getByRole('button', { name: '展开其余 2 个会话' }))
-    expectRows(12)
-    fireEvent.click(screen.getByRole('button', { name: '收起' }))
-    expectRows(5)
-    fireEvent.click(screen.getByText('alpha'))
-    fireEvent.click(screen.getByText('alpha'))
-    expectRows(5)
-  })
-
-  it('reveals a hidden session when live running status starts and folds it when the run ends', () => {
+  it('raises the watermark to the last attention row and keeps it after the attention ends', () => {
    const items = Array.from({ length: 12 }, (_, index) => summary(`session-${index + 1}`, 12 - index))
    const b = mount({
      useSessions: hook(sessionState(items)),
      useWorkspaces: hook(workspaceState([workspace('alpha', items.map(item => item.id))])),
    })
+    const status = (id: string, value: Partial<SessionStatus>) =>
+      hook<SessionStatusSnapshot>(new Map([[sid(id), {
+        running: false, pendingInteraction: undefined, completionUnread: false, ...value,
+      }]]))
+    const expectVisible = (count: number) => {
+      expect(screen.getAllByRole('treeitem').map(row => within(row).getByText(/^(alpha|session-\d+)$/u).textContent))
+        .toEqual(['alpha', ...items.slice(0, count).map(item => item.displayTitle)])
+    }
    fireEvent.click(screen.getByText('alpha'))
-    expect(screen.queryByText('session-12')).toBeNull()
-    rerender(b, {
-      useSessionStatus: hook<SessionStatusSnapshot>(new Map([[sid('session-12'), {
-        running: true, pendingInteraction: undefined, completionUnread: false,
-      }]])),
-    })
-    expect(screen.getByText('session-12')).toBeTruthy()
-    expect(screen.queryByText('session-6')).toBeNull()
-    expect(screen.getByRole('button', { name: '展开其余 6 个会话' })).toBeTruthy()
-    rerender(b, {
-      useSessionStatus: hook<SessionStatusSnapshot>(new Map([[sid('session-12'), {
-        running: false, pendingInteraction: undefined, completionUnread: true,
-      }]])),
-    })
-    expect(screen.queryByText('session-12')).toBeNull()
-    expect(screen.getByRole('button', { name: '展开其余 7 个会话' })).toBeTruthy()
+    expectVisible(5)
+    rerender(b, { useSessionStatus: status('session-9', { running: true }) })
+    expectVisible(9)
+    expect(screen.getByRole('button', { name: '展开其余 3 个会话' })).toBeTruthy()
+    rerender(b, { useSessionStatus: status('session-9', {}) })
+    expectVisible(9)
+
+    fireEvent.click(screen.getByText('alpha'))
+    fireEvent.click(screen.getByText('alpha'))
+    expectVisible(5)
+    rerender(b, { useSessionStatus: status('session-7', {
+      pendingInteraction: { key: 'question:1', kind: 'plan-review', sessionId: sid('session-7') } as SessionPendingInteraction,
+    }) })
+    expectVisible(7)
+    rerender(b, { useSessionStatus: status('session-8', { completionUnread: true }) })
+    expectVisible(8)
+    fireEvent.click(screen.getByRole('button', { name: '展开其余 4 个会话' }))
+    expectVisible(12)
+    fireEvent.click(screen.getByRole('button', { name: '收起' }))
+    expectVisible(8)
  })

-  it('keeps a parent with a running child visible outside the idle-session quota', () => {
-    const items = Array.from({ length: 7 }, (_, index) => summary(`session-${index + 1}`, 7 - index))
+  it('stops automatic raises at 50 rows while Show more continues past them', () => {
+    const items = Array.from({ length: 60 }, (_, index) => summary(`session-${index + 1}`, 60 - index))
+    const b = mount({
+      useSessions: hook(sessionState(items)),
+      useWorkspaces: hook(workspaceState([workspace('alpha', items.map(item => item.id))])),
+    })
+    fireEvent.click(screen.getByText('alpha'))
+    const running = (...ids: string[]) => hook<SessionStatusSnapshot>(new Map(ids.map(id => [sid(id), {
+      running: true, pendingInteraction: undefined, completionUnread: false,
+    }])))
+    rerender(b, {
+      useSessions: hook(sessionState(items, { main: sid('session-53') })),
+      useSessionStatus: hook<SessionStatusSnapshot>(new Map([
+        [sid('session-55'), { running: true, pendingInteraction: undefined, completionUnread: false }],
+        [sid('session-56'), { running: false, pendingInteraction: undefined, completionUnread: true }],
+        [sid('session-57'), {
+          running: false, completionUnread: false,
+          pendingInteraction: { key: 'question:1', kind: 'question', sessionId: sid('session-57') } as SessionPendingInteraction,
+        }],
+      ])),
+    })
+    expect(screen.queryByText('session-6')).toBeNull()
+    for (const id of ['session-53', 'session-55', 'session-56', 'session-57']) expect(screen.queryByText(id)).toBeNull()
+    rerender(b, { useSessionStatus: running('session-50', 'session-55') })
+    expect(screen.getByText('session-50')).toBeTruthy()
+    expect(screen.queryByText('session-51')).toBeNull()
+    fireEvent.click(screen.getByRole('button', { name: '展开其余 10 个会话' }))
+    expect(screen.getByText('session-55')).toBeTruthy()
+    expect(screen.queryByText('session-56')).toBeNull()
+    fireEvent.click(screen.getByRole('button', { name: '展开其余 5 个会话' }))
+    expect(screen.getByText('session-60')).toBeTruthy()
+  })
+
+  it('covers the current session and a parent with a running child', () => {
+    const items = Array.from({ length: 9 }, (_, index) => summary(`session-${index + 1}`, 9 - index))
    const child = summary('child', 0, { origin: 'subagent', running: true })
-    mount({
+    const b = mount({
      useSessions: hook(sessionState([...items, child], {
        projectionsBySession: {
          [sid('session-7')]: {
@@ -839,8 +858,11 @@ describe('WorkspaceBrowser', () => {
    })
    fireEvent.click(screen.getByText('alpha'))
    expect(screen.getByText('session-7')).toBeTruthy()
-    expect(screen.queryByText('session-6')).toBeNull()
+    expect(screen.queryByText('session-8')).toBeNull()
    expect(screen.queryByText('child')).toBeNull()
+    rerender(b, { useSessions: hook(sessionState(items, { main: sid('session-8') })) })
+    expect(screen.getByText('session-8')).toBeTruthy()
+    expect(screen.queryByText('session-9')).toBeNull()
    expect(screen.getByRole('button', { name: '展开其余 1 个会话' })).toBeTruthy()
  })

@@ -1548,7 +1570,7 @@ describe('WorkspaceBrowser', () => {
    expect(b.store.getSnapshot().groupExpansion).not.toHaveProperty('stale')
  })

-  it('reveals every session when a search result is beyond the initial five-row quota', () => {
+  it('raises the watermark to a search result beyond the initial five rows', () => {
    const items = Array.from({ length: 17 }, (_, index) => summary(`session-${index + 1}`, 17 - index))
    const b = mount({
      useSessions: hook(sessionState(items)),
@@ -1560,16 +1582,28 @@ describe('WorkspaceBrowser', () => {

    expect(b.props.open).toHaveBeenCalledWith(sid('session-11'))
    expect(input.value).toBe('')
-    for (const item of items) expect(screen.getByText(item.displayTitle)).toBeTruthy()
-    expect(screen.queryByRole('button', { name: /展开其余/ })).toBeNull()
+    expect(screen.getByText('session-11')).toBeTruthy()
+    expect(screen.queryByText('session-12')).toBeNull()
    expect(scrollIntoView.mock.instances.at(-1)).toBe(screen.getByText('session-11').closest('[role="treeitem"]'))
-    fireEvent.click(screen.getByRole('button', { name: '收起' }))
+    fireEvent.click(screen.getByRole('button', { name: '展开其余 6 个会话' }))
+    expect(screen.getByText('session-16')).toBeTruthy()
+    fireEvent.click(screen.getByText('alpha'))
+    fireEvent.click(screen.getByText('alpha'))
    expect(screen.queryByText('session-6')).toBeNull()
-    expect(screen.queryByText('session-11')).toBeNull()
-    fireEvent.click(screen.getByRole('button', { name: '展开其余 12 个会话' }))
-    expect(screen.getByText('session-10')).toBeTruthy()
-    expect(screen.queryByText('session-11')).toBeNull()
-    expect(screen.getByRole('button', { name: '展开其余 7 个会话' })).toBeTruthy()
+    expect(screen.getByRole('button', { name: '展开其余 12 个会话' })).toBeTruthy()
+  })
+
+  it('reveals a search result beyond the automatic 50-row limit', () => {
+    const items = Array.from({ length: 60 }, (_, index) => summary(`session-${index + 1}`, 60 - index))
+    mount({
+      useSessions: hook(sessionState(items)),
+      useWorkspaces: hook(workspaceState([workspace('alpha', items.map(item => item.id))])),
+    })
+    fireEvent.change(screen.getByPlaceholderText('搜索会话名称'), { target: { value: 'session-58' } })
+    fireEvent.click(screen.getByRole('treeitem'))
+    expect(screen.getByText('session-58')).toBeTruthy()
+    expect(screen.queryByText('session-59')).toBeNull()
+    expect(screen.getByRole('button', { name: '展开其余 2 个会话' })).toBeTruthy()
  })

  it('keeps the bounded group projection when the revealed result is already within it', () => {
@@ -2418,6 +2452,55 @@ describe('Workspace tree grouping', () => {
    expect(within(section('Projects')).getByText('Child')).toBeTruthy()
  })

+  it('folding a parent Workspace resets descendant watermarks', () => {
+    const rootItems = Array.from({ length: 7 }, (_, index) => summary(`root-${index + 1}`, 30 - index))
+    const childItems = Array.from({ length: 7 }, (_, index) => summary(`child-${index + 1}`, 20 - index))
+    mount({
+      useSessions: hook(sessionState([...rootItems, ...childItems])),
+      useWorkspaces: hook(workspaceState([
+        { ...root, sessionIds: rootItems.map(item => item.id) },
+        { ...child, sessionIds: childItems.map(item => item.id) },
+      ])),
+    })
+    fireEvent.click(screen.getByText('Child'))
+    fireEvent.click(within(section('Child')).getByRole('button', { name: '展开其余 2 个会话' }))
+    fireEvent.click(within(section('Projects')).getAllByRole('button', { name: '展开其余 2 个会话' })[0]!)
+    expect(screen.getByText('child-7')).toBeTruthy()
+    expect(screen.getByText('root-7')).toBeTruthy()
+    fireEvent.click(screen.getByText('Child'))
+    fireEvent.click(screen.getByText('Child'))
+    expect(screen.queryByText('child-6')).toBeNull()
+    expect(screen.getByText('root-7')).toBeTruthy()
+    fireEvent.click(within(section('Child')).getByRole('button', { name: '展开其余 2 个会话' }))
+    fireEvent.click(screen.getByText('Projects'))
+    fireEvent.click(screen.getByText('Projects'))
+    expect(screen.queryByText('root-6')).toBeNull()
+    expect(screen.queryByText('child-6')).toBeNull()
+  })
+
+  it('does not raise a nested watermark while a folded ancestor hides it', () => {
+    const rootItems = [summary('root-1', 30)]
+    const childItems = Array.from({ length: 8 }, (_, index) => summary(`child-${index + 1}`, 20 - index))
+    const b = mount({
+      useSessions: hook(sessionState([...rootItems, ...childItems])),
+      useWorkspaces: hook(workspaceState([
+        { ...root, sessionIds: rootItems.map(item => item.id) },
+        { ...child, sessionIds: childItems.map(item => item.id) },
+      ])),
+    })
+    fireEvent.click(screen.getByText('Child'))
+    fireEvent.click(screen.getByText('Projects'))
+    const status = (running: boolean) => hook<SessionStatusSnapshot>(new Map([[sid('child-8'), {
+      running, pendingInteraction: undefined, completionUnread: false,
+    }]]))
+    rerender(b, { useSessionStatus: status(true) })
+    rerender(b, { useSessionStatus: status(false) })
+    fireEvent.click(screen.getByText('Projects'))
+    expect(screen.getByText('child-5')).toBeTruthy()
+    expect(screen.queryByText('child-6')).toBeNull()
+    expect(screen.queryByText('child-8')).toBeNull()
+  })
+
  it('nests newly registered ancestors and children while retaining each Workspace session', () => {
    const b = mount({
      useSessions: hook(sessionState([summary('root-session', 1), summary('team-session', 2), summary('child-session', 3)])),