Guard against updating notifications preferences without permissions

Author: hyphenized

background/services/preferences/index.ts

@@ -1,3 +1,4 @@
+import browser from "webextension-polyfill"
 import { FiatCurrency } from "../../assets"
 import { AddressOnNetwork, NameOnNetwork } from "../../accounts"
 import { ServiceLifecycleEvents, ServiceCreatorFunction } from "../types"
@@ -281,11 +282,21 @@ export default class PreferenceService extends BaseService<Events> {
     return (await this.db.getPreferences()).shouldShowNotifications
   }
 
+  /**
+   * This guards against invalid state by checking if permissions have
+   * been granted by the browser
+   */
   async setShouldShowNotifications(shouldShowNotifications: boolean) {
-    await this.db.setShouldShowNotifications(shouldShowNotifications)
-    this.emitter.emit("setNotificationsPermission", shouldShowNotifications)
+    const hasBrowserPermissions = await browser.permissions.contains({
+      permissions: ["notifications"],
+    })
+
+    const updatedValue = hasBrowserPermissions && shouldShowNotifications
+
+    await this.db.setShouldShowNotifications(updatedValue)
+    this.emitter.emit("setNotificationsPermission", updatedValue)
 
-    return shouldShowNotifications
+    return updatedValue
   }
 
   async getAccountSignerSettings(): Promise<AccountSignerSettings[]> {

background/services/redux/index.ts

@@ -1709,10 +1709,12 @@ export default class ReduxService extends BaseService<never> {
     uiSliceEmitter.on(
       "shouldShowNotifications",
       async (shouldShowNotifications: boolean) => {
-        await this.preferenceService.setShouldShowNotifications(
-          shouldShowNotifications,
-        )
-        this.store.dispatch(toggleNotifications(shouldShowNotifications))
+        const notificationsEnabled =
+          await this.preferenceService.setShouldShowNotifications(
+            shouldShowNotifications,
+          )
+
+        this.store.dispatch(toggleNotifications(notificationsEnabled))
       },
     )