fix(web): persist general preferences in host settings

packages/client/locale/tests/apply.spec.ts

@@ -4,7 +4,9 @@
 import { Context } from 'cordis'
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { SlotsService } from '@deepseek-ai/dsh-client-runtime/client'
-import { apply, inject, SETTINGS_NS } from '@deepseek-ai/dsh-client-locale/client'
+import {
+  apply, inject, LOCALE_SETTINGS_NAMESPACE, SETTINGS_NS,
+} from '@deepseek-ai/dsh-client-locale/client'
 import type { LanguageRowInjected, LocaleService } from '@deepseek-ai/dsh-client-locale/client'
 import { LanguageRow } from '../src/client/LanguageRow.tsx'
 import type { createLanguageRowStore } from '../src/client/settings-store.ts'
@@ -14,7 +16,36 @@ const SLOT = 'settings.general.item'
 async function bench() {
   const ctx = new Context()
   await ctx.plugin(SlotsService).await()
-  return { ctx, slots: ctx.get('slots') as SlotsService }
+  let preference: string | undefined
+  let revision = 0
+  const namespace = () => ({
+    ns: LOCALE_SETTINGS_NAMESPACE,
+    schema: {},
+    value: preference === undefined ? {} : { preference },
+    applies: 'live' as const,
+    secrets: [],
+    revision,
+  })
+  const describe = vi.fn(async () => ({
+    rpcId: 'locale-describe' as never,
+    result: {
+      ok: true as const,
+      value: { writable: true, hasDocument: true, namespaces: [namespace()] },
+    },
+  }))
+  const mutate = vi.fn(async (request: { ops: { value: string }[] }) => {
+    preference = request.ops[0]!.value
+    revision += 1
+    return {
+      rpcId: 'locale-mutate' as never,
+      result: { ok: true as const, value: namespace() },
+    }
+  })
+  ctx.provide('connection', { api: { settings: { describe, mutate } }, isLoopback: true } as never)
+  return {
+    ctx, slots: ctx.get('slots') as SlotsService, describe, mutate,
+    setHostPreference: (next: string | undefined) => { preference = next; revision += 1 },
+  }
 }
 
 /** Stand in for the settings shell: declare the General item slot from root. */
@@ -47,7 +78,7 @@ describe('locale apply', () => {
   })
 
   it('declares the slot service', () => {
-    expect(inject).toEqual(['slots'])
+    expect(inject).toEqual(['slots', 'connection'])
   })
 
   it('provides the service with base + settings dictionaries and registers the row (declaration before or after apply)', async () => {
@@ -91,6 +122,23 @@ describe('locale apply', () => {
     expect(locale.getLocale().active).toBe('zh')
     expect(instance.getSnapshot().active).toBe('zh')
     expect(locale.bind(SETTINGS_NS)('language.title')).toBe('语言')
+    await vi.waitFor(() => { expect(b.mutate).toHaveBeenCalledTimes(2) })
+  })
+
+  it('loads and refreshes the explicit Host preference after nonblocking activation', async () => {
+    const b = await bench()
+    b.setHostPreference('en')
+    declareItems(b.slots)
+    await b.ctx.plugin({ inject: [...inject], apply }).await()
+    const locale = b.ctx.get('locale') as LocaleService
+    await vi.waitFor(() => { expect(locale.getLocale().active).toBe('en') })
+    b.setHostPreference(undefined)
+    b.ctx.emit('settings/changed', LOCALE_SETTINGS_NAMESPACE)
+    await vi.waitFor(() => { expect(locale.getLocale().active).toBe('zh') })
+    b.setHostPreference('en')
+    b.ctx.emit('settings/changed', LOCALE_SETTINGS_NAMESPACE)
+    await vi.waitFor(() => { expect(locale.getLocale().active).toBe('en') })
+    expect(b.describe).toHaveBeenCalledTimes(3)
   })
 
   it('recovers after an HMR collapse of the declaring entry (stale disposer must not block)', async () => {

packages/client/locale/tests/host.spec.ts

@@ -0,0 +1,30 @@
+import { Context } from 'cordis'
+import { describe, expect, it } from 'vitest'
+import { Settings, settingsNamespace, type SettingsNamespace } from '@deepseek-ai/dsh-settings'
+import {
+  LOCALE_SETTINGS_NAMESPACE, apply,
+} from '@deepseek-ai/dsh-client-locale'
+
+class MemorySettings extends Settings {
+  readonly writable = true
+  protected load(): Promise<Record<string, unknown>> { return Promise.resolve({}) }
+  protected persist(_ns: SettingsNamespace, _section: Record<string, unknown>): Promise<void> {
+    return Promise.resolve()
+  }
+}
+
+describe('locale host', () => {
+  it('registers an optional explicit locale preference with the Host settings lifecycle', async () => {
+    const ctx = new Context()
+    await ctx.plugin(MemorySettings).await()
+    const fiber = ctx.plugin({ apply })
+    await fiber.await()
+    const ns = settingsNamespace(LOCALE_SETTINGS_NAMESPACE)
+    expect(ctx.settings.get(ns)).toEqual({})
+    await ctx.settings.update(ns, { preference: 'en' })
+    expect(ctx.settings.get(ns)).toEqual({ preference: 'en' })
+    await expect(ctx.settings.update(ns, { preference: 'fr' })).rejects.toThrow()
+    await fiber.dispose()
+    expect(ctx.settings.describe().map(row => row.ns)).not.toContain(ns)
+  })
+})

packages/client/locale/tests/invariant.spec.ts

@@ -14,16 +14,16 @@ describe('invariant companion', () => {
     await expect(ctx.plugin(LocaleInvariant).await()).resolves.toBeDefined()
   })
 
-  it('node-half apply is a no-op host placeholder', () => {
-    nodeApply()
-    expect(true).toBe(true) // reaching here without throw is the contract
+  it('node-half apply tolerates a Host without settings', () => {
+    nodeApply(new Context())
   })
 
   it('client apply provides ctx.locale seeded with the zh/en common namespace', async () => {
     // The feature registers its own Language settings row, hence the slots edge.
-    expect(inject).toEqual(['slots'])
+    expect(inject).toEqual(['slots', 'connection'])
     const ctx = new Context()
     new SlotsService(ctx)
+    ctx.provide('connection', { api: { settings: {} }, isLoopback: false } as never)
     await ctx.plugin({ inject, apply: clientApply }).await()
     const locale = ctx.get('locale')
     expect(locale).toBeInstanceOf(LocaleService)

packages/client/locale/tests/locale.spec.ts

@@ -2,7 +2,7 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { Context } from 'cordis'
 import type { LocaleSnapshot } from '@deepseek-ai/dsh-client-locale/client'
-import { LocaleService, STORAGE_KEY } from '@deepseek-ai/dsh-client-locale/client'
+import { LocaleService } from '@deepseek-ai/dsh-client-locale/client'
 
 const make = (): { ctx: Context; svc: LocaleService; events: LocaleSnapshot[] } => {
   const ctx = new Context()
@@ -24,7 +24,6 @@ const stubLanguages = (...tags: string[]): void => {
 
 describe('LocaleService', () => {
   beforeEach(() => {
-    localStorage.clear()
     // A Chinese browser is the baseline these specs assert their zh state on.
     stubLanguages('zh-CN')
   })
@@ -132,16 +131,19 @@ describe('LocaleService', () => {
     expect(svc.getSnapshot().revision).toBe(before + 1)
   })
 
-  it('setLocale persists, republishes an immutable snapshot, and no-ops on same value', () => {
+  it('setLocale requests persistence, republishes an immutable snapshot, and no-ops on same value', () => {
     const { svc, events } = make()
+    const persist = vi.fn()
+    svc.bindPersistence(persist)
     svc.setLocale('en')
     expect(svc.getLocale().active).toBe('en')
-    expect(localStorage.getItem(STORAGE_KEY)).toBe('en')
+    expect(persist).toHaveBeenCalledWith('en')
     expect(events).toHaveLength(1)
     expect(events[0]).toBe(svc.getLocale())
     expect(events[0]!.revision).toBe(1)
     svc.setLocale('en')
     expect(events).toHaveLength(1)
+    expect(persist).toHaveBeenCalledOnce()
   })
 
   it('throws on unknown locale ids', () => {
@@ -149,14 +151,19 @@ describe('LocaleService', () => {
     expect(() => { svc.setLocale('fr') }).toThrow('not registered')
   })
 
-  it('restores a persisted locale over the browser language, and garbage reads as no preference', () => {
-    localStorage.setItem(STORAGE_KEY, 'en')
-    expect(make().svc.getLocale().active).toBe('en')
-    localStorage.setItem(STORAGE_KEY, 'fr')
-    expect(make().svc.getLocale().active).toBe('zh')
+  it('syncs a Host preference over the browser language without writing it back', () => {
+    const { svc, events } = make()
+    const persist = vi.fn()
+    svc.bindPersistence(persist)
+    svc.syncPreference('en')
+    expect(svc.getLocale().active).toBe('en')
+    expect(events).toHaveLength(1)
+    expect(persist).not.toHaveBeenCalled()
+    svc.syncPreference('en')
+    expect(events).toHaveLength(1)
   })
 
-  it('opens in the browser language when nothing is persisted, matching regional variants on their primary subtag', () => {
+  it('opens provisionally in the browser language, matching regional variants on their primary subtag', () => {
     stubLanguages('en-GB', 'zh-CN')
     expect(make().svc.getLocale().active).toBe('en')
     stubLanguages('zh-Hant-TW')
@@ -176,8 +183,7 @@ describe('LocaleService', () => {
     expect(make().svc.getLocale().active).toBe('zh')
   })
 
-  it('runs outside a browser (node boots): the fallback decides, the machine language does not, writes no-op', () => {
-    vi.stubGlobal('localStorage', undefined)
+  it('runs outside a browser (node boots): the fallback decides and the machine language does not', () => {
     vi.stubGlobal('window', undefined)
     // Node exposes its own global navigator; without a window it must not
     // reach the resolution at all.
@@ -188,12 +194,11 @@ describe('LocaleService', () => {
     expect(svc.getLocale().active).toBe('en')
   })
 
-  it('keeps the browser language out of the way once a preference exists', () => {
+  it('lets an explicit in-process preference replace the browser-derived value', () => {
     stubLanguages('en-US')
     const { svc } = make()
     svc.setLocale('zh')
-    expect(localStorage.getItem(STORAGE_KEY)).toBe('zh')
-    expect(make().svc.getLocale().active).toBe('zh')
+    expect(svc.getLocale().active).toBe('zh')
   })
 
   it('exposes the two shipped locales with self-described labels', () => {