test: check what happens with cache when async storage rejects

Expensify · May 27, 2021 · 61c0c82 · 61c0c82
1 parent ceb4acf
commit 61c0c82
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Showing 2 changed files with 17 additions and 3 deletions.
diff --git a/lib/Onyx.js b/lib/Onyx.js
@@ -40,8 +40,8 @@ function get(key) {
             const parsed = JSON.parse(val);
             cache.update(key, parsed);
             return parsed;
-        })
-        .catch(err => logInfo(`Unable to get item from persistent storage. Key: ${key} Error: ${err}`)));
+        }))
+        .catch(err => logInfo(`Unable to get item from persistent storage. Key: ${key} Error: ${err}`));
 }
 
 /**

diff --git a/tests/unit/onyxCacheTest.js b/tests/unit/onyxCacheTest.js
@@ -103,7 +103,7 @@ describe('Onyx', () => {
                 // WHEN a value is retrieved
                 const result = await cache.getValue('mockKey', mockFallback);
 
-                // THEN it should be undefined
+                // THEN the fallback should be used to retrieve the value
                 expect(result).toEqual('myResult');
                 expect(mockFallback).toHaveBeenCalledTimes(1);
             });
@@ -146,6 +146,20 @@ describe('Onyx', () => {
                 expect(results[3]).toEqual('Result for mockKey1');
                 expect(results[4]).toEqual('Result for mockKey2');
             });
+
+            it('Should not store cache if the fallback method failed', async () => {
+                // GIVEN empty cache and a fallback function that rejects
+                const mockFallback = jest.fn().mockRejectedValue(
+                    new Error('Unable to get item from persistent storage')
+                );
+
+                // WHEN a value is retrieved
+                return cache.getValue('mockKey', mockFallback)
+                    .catch(() => {
+                        // THEN no value should be in cache
+                        expect(cache.hasCacheForKey('mockKey')).toBe(false);
+                    });
+            });
         });
 
         describe('hasCacheForKey', () => {