Fix rewards page local storage loader (uplift to 1.38.x)

components/brave_rewards/resources/android_page/storage.ts

@@ -85,19 +85,29 @@ export const defaultState: Rewards.State = {
 
 export const load = (): Rewards.State => {
   const data = window.localStorage.getItem(keyName)
-  let state: Rewards.State = defaultState
-  if (data) {
-    try {
-      state = JSON.parse(data)
-      if (!state || state.version !== defaultState.version) {
-        throw new Error('State versions do not match')
-      }
-      state.initializing = true
-    } catch (e) {
-      console.error('Could not parse local storage data: ', e)
-    }
+  if (!data) {
+    return defaultState
+  }
+
+  let parsedData: any
+  try {
+    parsedData = JSON.parse(data)
+  } catch {
+    parsedData = null
+  }
+
+  if (!parsedData || typeof parsedData !== 'object') {
+    console.error('Local storage data is not an object')
+    return defaultState
+  }
+
+  if (parsedData.version !== defaultState.version) {
+    console.error('Local storage state version does not match')
+    return defaultState
   }
-  return state
+
+  parsedData.initializing = true
+  return parsedData as Rewards.State
 }
 
 export const debouncedSave = debounce((data: Rewards.State) => {

components/brave_rewards/resources/page/storage.test.ts

@@ -0,0 +1,39 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { load, defaultState } from './storage'
+
+describe('local storage', () => {
+  describe('loading', () => {
+    it('returns default state if local storage data is not present', () => {
+      expect(load()).toEqual(defaultState)
+    })
+
+    it('returns default state if local storage is not JSON', () => {
+      localStorage['rewards-data'] = 'abc'
+      expect(load()).toEqual(defaultState)
+    })
+
+    it('returns default state if local storage is not JSON object', () => {
+      localStorage['rewards-data'] = '[]'
+      expect(load()).toEqual(defaultState)
+    })
+
+    it('returns default state if local storage is empty JSON object', () => {
+      localStorage['rewards-data'] = '{}'
+      expect(load()).toEqual(defaultState)
+    })
+
+    it('returns default state if local storage version does not match', () => {
+      localStorage['rewards-data'] = '{ "version": 0 }'
+      expect(load()).toEqual(defaultState)
+    })
+
+    it('returns loaded state with initializing flag set', () => {
+      const mockData = { version: defaultState.version }
+      localStorage['rewards-data'] = JSON.stringify(mockData)
+      expect(load()).toEqual({ ...mockData, initializing: true })
+    })
+  })
+})

components/brave_rewards/resources/page/storage.ts

@@ -85,19 +85,29 @@ export const defaultState: Rewards.State = {
 
 export const load = (): Rewards.State => {
   const data = window.localStorage.getItem(keyName)
-  let state: Rewards.State = defaultState
-  if (data) {
-    try {
-      state = JSON.parse(data)
-      if (!state || state.version !== defaultState.version) {
-        throw new Error('State versions do not match')
-      }
-      state.initializing = true
-    } catch (e) {
-      console.error('Could not parse local storage data: ', e)
-    }
+  if (!data) {
+    return defaultState
+  }
+
+  let parsedData: any
+  try {
+    parsedData = JSON.parse(data)
+  } catch {
+    parsedData = null
+  }
+
+  if (!parsedData || typeof parsedData !== 'object') {
+    console.error('Local storage data is not an object')
+    return defaultState
+  }
+
+  if (parsedData.version !== defaultState.version) {
+    console.error('Local storage state version does not match')
+    return defaultState
   }
-  return state
+
+  parsedData.initializing = true
+  return parsedData as Rewards.State
 }
 
 export const debouncedSave = debounce((data: Rewards.State) => {