feat(hub-ui): reopen a group's last-opened member ahead of defaultChildId

docs/content/1.guide/16.hub.md

@@ -214,7 +214,7 @@ ctx.docks.register({
 })
 ```
 
-Group and members stay independent top-level entries in `devframe:docks`; `defaultChildId` opens on activation. Grouping affects the dock rail, not iframes — to share **one** soft-navigated iframe, give docks a shared `frameId` and mark the anchor with `subTabs` ([Shared-iframe soft navigation](/guide/client-context#shared-iframe-soft-navigation)).
+Group and members stay independent top-level entries in `devframe:docks`. Activating the group reopens the member last opened in it (remembered per tab), and `defaultChildId` before any member has been opened. Grouping affects the dock rail, not iframes — to share **one** soft-navigated iframe, give docks a shared `frameId` and mark the anchor with `subTabs` ([Shared-iframe soft navigation](/guide/client-context#shared-iframe-soft-navigation)).
 
 ### The dual role of `category`
 

packages/hub-ui/src/client/components/dock/DockGroupButton.stories.ts

@@ -20,7 +20,7 @@ const meta = {
   parameters: {
     docs: {
       description: {
-        component: 'The dock-bar button representing a group. Click behaviour depends on the group: a group with `defaultChildId` opens that member directly, otherwise it reveals a popover of members. `FloatingElements` is mounted alongside so the popover renders.',
+        component: 'The dock-bar button representing a group. Clicking opens the member last opened in the group (remembered per tab), then the group\'s `defaultChildId`; with neither it reveals a popover of members. `FloatingElements` is mounted alongside so the popover renders.',
       },
     },
   },
@@ -30,8 +30,9 @@ export default meta
 type Story = StoryObj
 
 /**
- * A popover-only group (no `defaultChildId`): clicking reveals the member
- * popover.
+ * A popover-only group (no `defaultChildId`): the first click reveals the
+ * member popover. Picking a member records it as the group's last-opened
+ * child, so later clicks reopen it directly.
  */
 export const PopoverOnly: Story = {
   render: () => ({
@@ -53,7 +54,8 @@ export const PopoverOnly: Story = {
 
 /**
  * A group with a `defaultChildId`: clicking opens that member straight away
- * instead of showing the popover.
+ * instead of showing the popover — until another member becomes the group's
+ * last-opened child, which then takes precedence.
  */
 export const WithDefaultChild: Story = {
   render: () => ({

packages/hub-ui/src/client/components/dock/DockGroupButton.vue

@@ -3,7 +3,7 @@ import type { DevframeDockEntry, DevframeViewGroup } from '@devframes/hub'
 import type { DocksContext } from '@devframes/hub/client'
 import { watchDebounced } from '@vueuse/core'
 import { computed, h, ref, useTemplateRef } from 'vue'
-import { getGroupMembers, getGroupMembersGrouped, resolveGroupDefaultChild } from '../../state/dock-settings'
+import { getGroupMembers, getGroupMembersGrouped, resolveGroupPreferredChild } from '../../state/dock-settings'
 import { setDocksGroupPanel, useDocksGroupPanel } from '../../state/floating-tooltip'
 import { useSettings } from '../../state/settings-defaults'
 import { accentVarStyle } from '../../utils/accent-color'
@@ -101,13 +101,14 @@ function onClick() {
     emit('select', undefined!)
     return
   }
-  // `defaultChildId` opens its member directly; otherwise reveal the popover.
-  // Resolved regardless of the target's render-only `visibility` (a hidden
-  // button must still fire), but honoring its `when` clause.
-  const fallback = resolveGroupDefaultChild(
+  // The member last opened in this group this tab — then the author's
+  // `defaultChildId` — opens directly; otherwise reveal the popover. Resolved
+  // regardless of the target's render-only `visibility` (a hidden button must
+  // still fire), but honoring its `when` clause.
+  const fallback = resolveGroupPreferredChild(
     props.context.docks.entries,
-    props.group.id,
-    props.group.defaultChildId,
+    props.group,
+    props.context.panel.session.groupLastChildIds?.[props.group.id],
     props.context.when.context,
   )
   if (fallback) {

packages/hub-ui/src/client/state/context.test.ts

@@ -131,6 +131,43 @@ describe('createDocksContext', () => {
     expect(session.value.open).toBe(true)
   })
 
+  it('reopens a group\'s last-opened member ahead of defaultChildId', async () => {
+    expect.assertions(4)
+
+    const { rpc, sharedStates, trust } = createStubRpc()
+    // No `groupLastChildIds` seed — mirrors a session store persisted before
+    // the field existed.
+    const session = ref<DockSessionStorage>({
+      open: false,
+      selectedDockId: null,
+      selectedDockRoute: null,
+    })
+    const context = await createDocksContext('embedded', rpc, undefined, session)
+
+    trust()
+    sharedStates.get('devframe:docks')!.push([
+      { id: 'nuxt', type: 'group', title: 'Nuxt', icon: 'ph:cube-duotone', defaultChildId: 'nuxt:overview' },
+      { id: 'nuxt:overview', type: 'iframe', url: '/', title: 'Overview', icon: 'ph:cube-duotone', groupId: 'nuxt' },
+      { id: 'nuxt:modules', type: 'iframe', url: '/', title: 'Modules', icon: 'ph:cube-duotone', groupId: 'nuxt' },
+    ] satisfies DevframeDockEntry[])
+    sharedStates.get('devframe:dock-renderers')!.push({})
+    await flushRestore()
+
+    // Without memory the group activation resolves to `defaultChildId`.
+    await context.docks.switchEntry('nuxt')
+    expect(context.docks.selected?.id).toBe('nuxt:overview')
+
+    // Opening another member records it as the group's last-opened child.
+    await context.docks.switchEntry('nuxt:modules')
+    expect(session.value.groupLastChildIds).toEqual({ nuxt: 'nuxt:modules' })
+
+    // Closing and re-activating the group reopens the remembered member.
+    await context.docks.switchEntry(null)
+    expect(context.docks.selected).toBeNull()
+    await context.docks.switchEntry('nuxt')
+    expect(context.docks.selected?.id).toBe('nuxt:modules')
+  })
+
   it('keeps a dock closed when the user closes it before initialization finishes', async () => {
     expect.assertions(2)
 

packages/hub-ui/src/client/state/context.ts

@@ -11,7 +11,7 @@ import { computed, markRaw, reactive, ref, toRefs, watch, watchEffect } from 'vu
 import { BUILTIN_ENTRIES, BUILTIN_ENTRY_SETTINGS, DEFAULT_CATEGORIES_ORDER, HUB_UI_HIDE_EVENT } from '../constants'
 import { useBranding } from './branding'
 import { createCommandsContext } from './commands'
-import { docksGroupByCategories, getCategoryLabel, getGroupMembers, getGroupMembersGrouped, getRegisteredGroupIds, resolveCommandIcon, resolveGroupDefaultChild } from './dock-settings'
+import { docksGroupByCategories, getCategoryLabel, getGroupMembers, getGroupMembersGrouped, getRegisteredGroupIds, resolveCommandIcon, resolveGroupPreferredChild } from './dock-settings'
 import { createDockEntryState, DEFAULT_DOCK_PANEL_STORE, DEFAULT_DOCK_SESSION_STORE, sharedStateToRef, useDocksEntries, waitForInitialSharedStateSync } from './docks'
 import { createClientMessagesClient } from './messages-client'
 import { registerMainFrameDockActionHandler, triggerMainFrameDockAction, useIsDockPopupOpen } from './popup'
@@ -233,13 +233,14 @@ export async function createDocksContext(
       return false
 
     // A group has no view of its own — resolve to the member it represents.
-    // Prefer the author's `defaultChildId` (honoring its `when` clause but
-    // ignoring its render-only `visibility` — see `resolveGroupDefaultChild`),
-    // otherwise the first member. With neither, the group is popover-only and
-    // selecting it is a no-op here (the dock-bar group button opens the
-    // member popover instead).
+    // Prefer the member last opened in this group this tab, then the author's
+    // `defaultChildId` (each honoring its `when` clause but ignoring its
+    // render-only `visibility` — see `resolveGroupPreferredChild`), otherwise
+    // the first member. With none, the group is popover-only and selecting it
+    // is a no-op here (the dock-bar group button opens the member popover
+    // instead).
     if (entry.type === 'group') {
-      const target = resolveGroupDefaultChild(entries.value, entry.id, entry.defaultChildId, getWhenContext())?.id
+      const target = resolveGroupPreferredChild(entries.value, entry, sessionStore.value.groupLastChildIds?.[entry.id], getWhenContext())?.id
         ?? getGroupMembers(entries.value, entry.id)[0]?.id
       if (!target)
         return false
@@ -291,6 +292,13 @@ export async function createDocksContext(
     if (entry.type === 'iframe' && entry.frameId && !entry.subTabs)
       frameNavCurrentMember.set(entry.frameId, entry.id)
 
+    // Remember a grouped member as its group's last-opened child so the next
+    // activation of the group reopens it directly, ahead of `defaultChildId`
+    // (see `resolveGroupPreferredChild`). Guarded assignment: a session store
+    // persisted before this field existed has no map yet.
+    if (entry.groupId)
+      (sessionStore.value.groupLastChildIds ??= {})[entry.groupId] = entry.id
+
     initialRestorePending.value = false
     selectedDockId.value = entry.id
     sessionStore.value.open = true

packages/hub-ui/src/client/state/dock-settings.test.ts

@@ -1,6 +1,7 @@
 import type { DevframeDockEntriesGrouped, DevframeDockEntry, DevframeViewGroup } from '@devframes/hub'
+import type { WhenContext } from 'devframe/utils/when'
 import { describe, expect, it } from 'vitest'
-import { docksSplitGroupsWithCapacity, resolveNextRecentDockId, resolveRecentDockEntry } from './dock-settings'
+import { docksSplitGroupsWithCapacity, resolveGroupPreferredChild, resolveNextRecentDockId, resolveRecentDockEntry } from './dock-settings'
 
 function iframe(id: string, extra: Partial<DevframeDockEntry> = {}): DevframeDockEntry {
   return { id, type: 'iframe', url: '/', title: id.toUpperCase(), icon: 'ph:cube-duotone', ...extra } as DevframeDockEntry
@@ -104,6 +105,36 @@ describe('resolveNextRecentDockId', () => {
   })
 })
 
+describe('resolveGroupPreferredChild', () => {
+  const g = group('g', { defaultChildId: 'g:default' }) as DevframeViewGroup
+  const defaultMember = iframe('g:default', { groupId: 'g' })
+  const otherMember = iframe('g:other', { groupId: 'g' })
+  const entries = [a, g, defaultMember, otherMember]
+
+  it('prefers the last-opened member over defaultChildId', () => {
+    expect(resolveGroupPreferredChild(entries, g, 'g:other')).toBe(otherMember)
+  })
+
+  it('falls back to defaultChildId before any member has been opened', () => {
+    expect(resolveGroupPreferredChild(entries, g, undefined)).toBe(defaultMember)
+  })
+
+  it('falls back to defaultChildId when the remembered member is gone', () => {
+    expect(resolveGroupPreferredChild([a, g, defaultMember], g, 'g:other')).toBe(defaultMember)
+  })
+
+  it('falls back to defaultChildId when the remembered member fails its when clause', () => {
+    const whenContext: WhenContext = { clientType: 'standalone', dockOpen: false, paletteOpen: false, dockSelectedId: '' }
+    const gated = iframe('g:gated', { groupId: 'g', when: 'clientType == embedded' })
+    expect(resolveGroupPreferredChild([g, defaultMember, gated], g, 'g:gated', whenContext)).toBe(defaultMember)
+  })
+
+  it('resolves nothing for a popover-only group without memory', () => {
+    const bare = group('bare') as DevframeViewGroup
+    expect(resolveGroupPreferredChild([bare, iframe('bare:x', { groupId: 'bare' })], bare, undefined)).toBeUndefined()
+  })
+})
+
 describe('resolveRecentDockEntry', () => {
   const g = group('g')
   const member = iframe('g:member', { groupId: 'g' })

packages/hub-ui/src/client/state/dock-settings.ts

@@ -219,6 +219,28 @@ export function resolveGroupDefaultChild(
   return member
 }
 
+/**
+ * Resolve the member a group activation opens, layering the per-tab "last
+ * opened member" memory (`DockSessionStorage.groupLastChildIds`) over the
+ * author's `defaultChildId`. The remembered member wins while it still
+ * resolves — it exists in the group and its `when` clause holds — so reopening
+ * a group lands back on the member the developer last used; otherwise the
+ * `defaultChildId` target is tried under the same rules (both via
+ * {@link resolveGroupDefaultChild}, so the render-only `visibility` clause is
+ * ignored for either candidate). Returns `undefined` when neither resolves —
+ * the caller falls back to its own behavior (the dock-bar group button opens
+ * the member popover; `switchEntry` picks the first member).
+ */
+export function resolveGroupPreferredChild(
+  entries: DevframeDockEntry[],
+  group: DevframeViewGroup,
+  lastChildId: string | undefined,
+  whenContext?: WhenContext,
+): DevframeDockEntry | undefined {
+  return resolveGroupDefaultChild(entries, group.id, lastChildId, whenContext)
+    ?? resolveGroupDefaultChild(entries, group.id, group.defaultChildId, whenContext)
+}
+
 /**
  * Group and sort dock entries based on user settings.
  * Filters out hidden entries and categories, then sorts by custom order and

packages/hub-ui/src/client/state/docks.ts

@@ -30,6 +30,7 @@ export function DEFAULT_DOCK_SESSION_STORE(): DockSessionStorage {
     selectedDockId: null,
     selectedDockRoute: null,
     recentDockId: null,
+    groupLastChildIds: {},
   }
 }
 

packages/hub/src/client/docks.ts

@@ -50,6 +50,17 @@ export interface DockSessionStorage {
    * field existed) when no entry has been raised.
    */
   recentDockId?: string | null
+  /**
+   * The member most recently opened in each dock group, keyed by group id.
+   * Recorded whenever a grouped member is selected (from the group popover,
+   * the group sidebar, the command palette, or an RPC activation), and read
+   * back when the group is activated again: the remembered member reopens
+   * directly, taking precedence over the group's own
+   * {@link import('../types/docks').DevframeViewGroup.defaultChildId defaultChildId}.
+   * A group is only listed once one of its members has been opened this tab
+   * (absent for stores persisted before this field existed).
+   */
+  groupLastChildIds?: Record<string, string>
 }
 
 export type DockClientType = 'embedded' | 'standalone'

tests/__snapshots__/tsnapi/@devframes/hub/client.snapshot.d.ts

@@ -111,6 +111,7 @@ export interface DockSessionStorage {
   selectedDockId: string | null;
   selectedDockRoute: string | null;
   recentDockId?: string | null;
+  groupLastChildIds?: Record<string, string>;
 }
 export interface DocksPanelContext {
   store: DockPanelStorage;