fix: coalesce concurrent notification count reads

src/modules/notifications/notifications.test.mjs

@@ -36,7 +36,7 @@ test('keeps customer message actions first and covers the requested local states
   assert.match(source, /notification-state--error/)
   assert.match(source, /暂无消息/)
   assert.doesNotMatch(source, /清空已读|删除消息/)
-  assert.match(source, /Promise\.all\(\[load\(\), notifications\.refreshUnreadCount\(\)\]\)/)
+  assert.match(source, /Promise\.all\(\[load\(\), notifications\.refreshUnreadCount\(true\)\]\)/)
   assert.match(source, /auth\.hasPermission\('merchant:notification:read'\)/)
   assert.match(source, /auth\.hasPermission\('merchant:notification:read-all'\)/)
   assert.match(source, /v-if="canMarkAllRead"/)

src/modules/notifications/store/notifications.test.mjs

@@ -0,0 +1,49 @@
+import test from 'node:test'
+import assert from 'node:assert/strict'
+import { readFileSync } from 'node:fs'
+import ts from 'typescript'
+import { computed, ref } from 'vue'
+
+function setup() {
+  const requests = []
+  const source = readFileSync(new URL('./notifications.ts', import.meta.url), 'utf8').replace(/^import [^\r\n]*\r?\n/gm, '').replace('export const', 'const')
+  const code = ts.transpileModule(source, { compilerOptions: { target: ts.ScriptTarget.ES2022 } }).outputText
+  const store = new Function('computed', 'ref', 'defineStore', 'getMyUnreadNotificationCount', code + '\nreturn useNotificationsStore()')(computed, ref, (_id, factory) => factory, () => new Promise((resolve, reject) => requests.push({ resolve, reject })))
+  return { store, requests }
+}
+
+test('shell and page concurrent reads share one pending request', async () => {
+  const { store, requests } = setup()
+  const a = store.refreshUnreadCount(), b = store.refreshUnreadCount()
+  assert.equal(requests.length, 1)
+  requests[0].resolve(5)
+  await Promise.all([a, b])
+  assert.equal(store.unreadCount.value, 5)
+  assert.equal(store.loading.value, false)
+})
+
+test('post-mutation refresh reads again after a pending pre-mutation read', async () => {
+  const { store, requests } = setup()
+  const a = store.refreshUnreadCount(), b = store.refreshUnreadCount(true)
+  assert.equal(requests.length, 1)
+  requests[0].resolve(5)
+  await a
+  await Promise.resolve()
+  assert.equal(requests.length, 2)
+  requests[1].resolve(0)
+  await b
+  assert.equal(store.unreadCount.value, 0)
+})
+
+test('failed request releases the pending guard for retry', async () => {
+  const { store, requests } = setup()
+  const a = store.refreshUnreadCount()
+  requests[0].reject(new Error('network'))
+  await a
+  const b = store.refreshUnreadCount()
+  assert.equal(requests.length, 2)
+  requests[1].resolve(2)
+  await b
+  assert.equal(store.unreadCount.value, 2)
+  assert.equal(store.errorMessage.value, '')
+})

src/modules/notifications/store/notifications.ts

@@ -9,7 +9,19 @@ export const useNotificationsStore = defineStore('client-notifications', () => {
 
   const hasUnread = computed(() => (unreadCount.value ?? 0) > 0)
 
-  async function refreshUnreadCount() {
+  let pending: Promise<void> | null = null
+
+  async function refreshUnreadCount(afterMutation = false): Promise<void> {
+    if (pending) {
+      if (!afterMutation) return pending
+      await pending
+      return refreshUnreadCount()
+    }
+    pending = loadUnreadCount().finally(() => { pending = null })
+    return pending
+  }
+
+  async function loadUnreadCount() {
     loading.value = true
     errorMessage.value = ''
     try {

src/modules/notifications/views/NotificationDetailView.vue

@@ -10,7 +10,7 @@ import type { NotificationDetail } from '../contracts'
 import { notificationCategoryLabel, notificationSentAt } from '../presentation'
 const route = useRoute(); const router = useRouter(); const auth = useAuthStore(); const notifications = useNotificationsStore(); const detail = ref<NotificationDetail | null>(null); const loading = ref(false); const errorMessage = ref(''); const readErrorMessage = ref('')
 const canMarkRead = computed(() => auth.hasPermission('merchant:notification:read'))
-async function markReadIfAllowed(){if(!detail.value||detail.value.status!=='UNREAD'||!canMarkRead.value)return;try{await markMyNotificationRead(detail.value.id);detail.value={...detail.value,status:'READ'};await notifications.refreshUnreadCount()}catch(error){readErrorMessage.value=error instanceof ApiError?error.message:'消息已加载，但自动标记已读失败'}}
+async function markReadIfAllowed(){if(!detail.value||detail.value.status!=='UNREAD'||!canMarkRead.value)return;try{await markMyNotificationRead(detail.value.id);detail.value={...detail.value,status:'READ'};await notifications.refreshUnreadCount(true)}catch(error){readErrorMessage.value=error instanceof ApiError?error.message:'消息已加载，但自动标记已读失败'}}
 async function load(){loading.value=true;errorMessage.value='';readErrorMessage.value='';try{detail.value=await getMyNotification(String(route.params.notificationId));await markReadIfAllowed()}catch(error){detail.value=null;errorMessage.value=error instanceof ApiError?error.message:'消息加载失败，请稍后重试'}finally{loading.value=false}}
 onMounted(()=>{void load()})
 </script>

src/modules/notifications/views/NotificationsView.vue

@@ -78,7 +78,7 @@ async function markRead(row: NotificationSummary) {
   if (!canMarkRead.value) return
   try {
     await markMyNotificationRead(row.id)
-    await Promise.all([load(), notifications.refreshUnreadCount()])
+    await Promise.all([load(), notifications.refreshUnreadCount(true)])
   } catch (error) {
     errorMessage.value = messageOf(error)
   }
@@ -89,7 +89,7 @@ async function markAllRead() {
   markingAll.value = true
   try {
     await markAllMyNotificationsRead()
-    await Promise.all([load(), notifications.refreshUnreadCount()])
+    await Promise.all([load(), notifications.refreshUnreadCount(true)])
   } catch (error) {
     errorMessage.value = messageOf(error)
   } finally {