fix: incorrect flag for diff algorithm

Author: Saviio

src/utils/diff.ts

@@ -174,7 +174,7 @@ export function diff<T>(oldList: T[], newList: T[], pk = '_id'): Ops {
     }
   }
 
-  const arrayIsSame = reused === curr.length && prev.length === curr.length
+  const arrayIsSame = reused === curr.length && prev.length === curr.length && reused !== 0
   return {
     type: arrayIsSame ? OpsType.SuccessAndSkip : OpsType.Success,
     ops: ret,

test/specs/utils/diff.spec.ts

@@ -328,6 +328,13 @@ export default describe('Diff Testcase: ', () => {
       const result = diff([{ id: 1, a: 1 }], [{ id: 1, a: 1 }], 'id')
       expect(result.type).to.equal(2)
     })
+
+    it('should be able to use old list except reused number is 0: 27', () => {
+      // when old list is empty & new list is empty
+      // should not return skip flag
+      const result = diff([], [], 'id')
+      expect(result.type).to.equal(1)
+    })
   })
 
   describe('Function: getPatchResult', () => {