From c1e2acf98ab7943de1e58464a9623a48d84a7cbc Mon Sep 17 00:00:00 2001
From: Noel De Martin <noel@moodle.com>
Date: Mon, 7 Jun 2021 17:20:29 +0200
Subject: [PATCH] MOBILE-3320 user: Make preferences fail-safe

---
 src/addons/calendar/services/calendar.ts |  6 +++---
 src/core/features/user/services/user.ts  | 15 +++++----------
 2 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/src/addons/calendar/services/calendar.ts b/src/addons/calendar/services/calendar.ts
index 4dfb9fffd..0d3c84412 100644
--- a/src/addons/calendar/services/calendar.ts
+++ b/src/addons/calendar/services/calendar.ts
@@ -566,14 +566,14 @@ export class AddonCalendarProvider {
      */
     async getCalendarLookAhead(siteId?: string): Promise<number> {
         const site = await CoreSites.getSite(siteId);
-        let value: string | undefined;
+        let value: string | undefined | null;
         try {
             value = await CoreUser.getUserPreference('calendar_lookahead');
         } catch {
             // Ignore errors.
         }
 
-        if (typeof value == 'undefined') {
+        if (typeof value == 'undefined' || value === null) {
             value = site.getStoredConfig('calendar_lookahead');
         }
 
@@ -588,7 +588,7 @@ export class AddonCalendarProvider {
      */
     async getCalendarTimeFormat(siteId?: string): Promise<string> {
         const site = await CoreSites.getSite(siteId);
-        let format: string | undefined;
+        let format: string | undefined | null;
 
         try {
             format = await CoreUser.getUserPreference('calendar_timeformat');
diff --git a/src/core/features/user/services/user.ts b/src/core/features/user/services/user.ts
index 6033f8efd..6dfc08bfa 100644
--- a/src/core/features/user/services/user.ts
+++ b/src/core/features/user/services/user.ts
@@ -391,7 +391,7 @@ export class CoreUserProvider {
      * @param siteId Site Id. If not defined, use current site.
      * @return Preference value or null if preference not set.
      */
-    async getUserPreference(name: string, siteId?: string): Promise<string> {
+    async getUserPreference(name: string, siteId?: string): Promise<string | null> {
         siteId = siteId || CoreSites.getCurrentSiteId();
 
         const preference = await CoreUtils.ignoreErrors(CoreUserOffline.getPreference(name, siteId));
@@ -403,20 +403,15 @@ export class CoreUserProvider {
 
         const wsValue = await this.getUserPreferenceOnline(name, siteId);
 
-        if (!wsValue) {
-            if (preference) {
-                // Return the local value.
-                return preference.value;
-            }
-
-            throw new CoreError('Preference not found');
-        }
-
         if (preference && preference.value != preference.onlinevalue && preference.onlinevalue == wsValue) {
             // Sync is pending for this preference, return stored value.
             return preference.value;
         }
 
+        if (!wsValue) {
+            return null;
+        }
+
         await CoreUserOffline.setPreference(name, wsValue, wsValue);
 
         return wsValue;