added more comments

Author: jcguarinpenaranda

src/ParseOffline.ts

@@ -51,12 +51,13 @@ export class ParseOffline {
   }): CachedResults {
     const { className, localStorageKey } = params;
 
+    // Get the previous items in the localStorage
     const previousItems = window.localStorage.getItem(
       localStorageKey || // from an arbitrary key
       ParseOffline.getLocalStorageKeyForClassName(className), // for an autogenerated key
     );
 
-    // return if there were no previous items
+    // return an empty set if there were no previous items
     if (!previousItems) return new CachedResults([]);
 
     // parse the previous results
@@ -119,6 +120,7 @@ export class ParseOffline {
 
       if (maxAge && !ParseOffline.areCachedResultsValid(cachedResults, maxAge)) {
         throw new Error('Cached results are not valid anymore');
+        // return [];
       }
 
       return cachedResults.toParseObjs(query.className);