fix: Unable to switch off the stats collecting

src/entrypoints/background/persistent/settings.test.ts

@@ -1,4 +1,5 @@
 import { describe, expect, test } from 'vitest'
+import type { SettingsState } from '../../../shared/types/settings'
 import Settings from './settings'
 import StorageArea from './storage-area'
 
@@ -12,7 +13,7 @@ describe('settings', () => {
     }
 
     async set<T>(v: T): Promise<void> {
-      this.state = v as Record<string, unknown>
+      this.state = JSON.parse(JSON.stringify(v)) as Record<string, unknown>
     }
 
     async get<T>(): Promise<T | undefined> {
@@ -52,6 +53,40 @@ describe('settings', () => {
     expect((await settings.get()).renew.intervalMillis).toEqual(30000)
   })
 
+  test('partial from storage', async () => {
+    const area: StorageArea<SettingsState> = new StorageAreaMock('some-key', 'local')
+    const settings = new Settings(area)
+
+    await settings.update({ enabled: false, remoteUseragentList: { uri: 'foo' } }) // force to save
+
+    // read the current state and remove some key
+    {
+      const current = await area.get()
+      if (!current) {
+        throw new Error('current is undefined')
+      }
+
+      // @ts-expect-error - emulate partial data
+      delete current.stats
+
+      await area.set(current)
+    }
+
+    let executed = false
+
+    settings.onChange((s) => {
+      expect(s.stats).not.toBeUndefined()
+      expect(s.remoteUseragentList.uri).toEqual('foo')
+      expect(s.enabled).toBeTruthy()
+
+      executed = true
+    })
+
+    await settings.update({ enabled: true }) // force to save
+
+    expect(executed).toBeTruthy()
+  })
+
   test('onChange listener', async () => {
     const settings = new Settings(new StorageAreaMock('some-key', 'local'))
     let execCount = 0

src/entrypoints/background/persistent/settings.ts

@@ -106,8 +106,8 @@ export default class {
       delete updated.blacklist.custom
     }
 
-    const current = await this.storage.get()
-    const [merged, changes] = this.merge(structuredClone(current ?? this.defaults), updated)
+    const [current] = this.merge(this.defaults, (await this.storage.get()) ?? this.defaults)
+    const [merged, changes] = this.merge(structuredClone(current), updated)
 
     if (changes > 0) {
       // to clean in the storage