From 33f612e85b20a16bd87106d07bd63fadcb79ab95 Mon Sep 17 00:00:00 2001
From: Jay Meistrich <jmeistrich@gmail.com>
Date: Sat, 2 Nov 2024 11:25:02 +0000
Subject: [PATCH] fix: as "value" returning no results was setting to undefined
 rather than null from a recent commit

---
 src/sync-plugins/crud.ts | 12 +++++++-----
 tests/crud.test.ts       | 21 +++++++++++++++++++++
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/src/sync-plugins/crud.ts b/src/sync-plugins/crud.ts
index 015b8d07..2de4b6eb 100644
--- a/src/sync-plugins/crud.ts
+++ b/src/sync-plugins/crud.ts
@@ -241,11 +241,13 @@ export function syncedCrud<TRemote extends object, TLocal = TRemote, TAsOption e
                           // as Promise only if listFn returned a promise
                           const toOut = (transformed: TLocal[]) => {
                               if (asType === 'value') {
-                                  return transformed.length > 0
-                                      ? transformed[0]
-                                      : getFn
-                                        ? ((((isLastSyncMode && lastSync) || fieldDeleted) && value) ?? null)
-                                        : undefined;
+                                  if (transformed.length > 0) {
+                                      // Return first value
+                                      return transformed[0];
+                                  } else {
+                                      // Return null if no cached value, otherwise undefined to not overwrite it
+                                      return value ? undefined : null;
+                                  }
                               } else {
                                   return resultsToOutType(transformed);
                               }
diff --git a/tests/crud.test.ts b/tests/crud.test.ts
index 99ab2dde..004cf476 100644
--- a/tests/crud.test.ts
+++ b/tests/crud.test.ts
@@ -420,6 +420,27 @@ describe('Crud as value list', () => {
         await promiseTimeout(1);
 
         expect(obs$.get()).toEqual({ id: 'id', test: 'hi', updatedAt: 1 });
+        expect(syncState(obs$).isLoaded.get()).toEqual(true);
+    });
+    test('Set to null if returns []', async () => {
+        const persistName = getPersistName();
+        const obs$ = observable(
+            syncedCrud({
+                list: () => promiseTimeout(0, []),
+                as: 'value',
+                persist: {
+                    name: persistName,
+                    plugin: ObservablePersistLocalStorage,
+                },
+            }),
+        );
+
+        expect(obs$.get()).toEqual(undefined);
+
+        await promiseTimeout(1);
+
+        expect(obs$.get()).toEqual(null);
+        expect(syncState(obs$).isLoaded.get()).toEqual(true);
     });
     test('sets if returns new value', async () => {
         const persistName = getPersistName();