From 985e72e847b6cb4a6944dec2881d93ddf5daf725 Mon Sep 17 00:00:00 2001
From: Anthony Fu <anthonyfu117@hotmail.com>
Date: Sun, 24 Jul 2022 18:04:57 +0800
Subject: [PATCH] chore: update

---
 packages/core/useStorage/index.md      |  2 +-
 packages/core/useStorage/index.test.ts | 15 ++++++++++-----
 packages/core/useStorage/index.ts      | 10 +++++-----
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/packages/core/useStorage/index.md b/packages/core/useStorage/index.md
index 95b3a0aacd6..ff6fa241d94 100644
--- a/packages/core/useStorage/index.md
+++ b/packages/core/useStorage/index.md
@@ -60,7 +60,7 @@ console.log(state.hello) // 'nihao', from storage
 console.log(state.greeting) // 'hello', from merged default value
 ```
 
-When setting it to true, it will perform a **shallow merge** for objects/arrays. You can pass a custom merge function or deep merge, for example:
+When setting it to true, it will perform a **shallow merge** for objects. You can pass a function to perform custom merge (e.g. deep merge), for example:
 
 ```ts
 const state = useStorage(
diff --git a/packages/core/useStorage/index.test.ts b/packages/core/useStorage/index.test.ts
index e726efce839..51b2e563c3d 100644
--- a/packages/core/useStorage/index.test.ts
+++ b/packages/core/useStorage/index.test.ts
@@ -336,21 +336,26 @@ describe('useStorage', () => {
     // basic
     storage.setItem(KEY, '0')
     const basicRef = useStorage(KEY, 1, storage, { mergeDefaults: true })
-    expect(basicRef.value).toBe(1)
+    expect(basicRef.value).toBe(0)
 
     // object
     storage.setItem(KEY, JSON.stringify({ a: 1 }))
     const objectRef = useStorage(KEY, { a: 2, b: 3 }, storage, { mergeDefaults: true })
-    expect(JSON.stringify(objectRef.value)).toBe(JSON.stringify({ a: 2, b: 3 }))
+    expect(objectRef.value).toEqual({ a: 1, b: 3 })
 
     // array
     storage.setItem(KEY, JSON.stringify([1]))
     const arrayRef = useStorage(KEY, [2], storage, { mergeDefaults: true })
-    expect(JSON.stringify(arrayRef.value)).toBe(JSON.stringify([1, 2]))
+    expect(arrayRef.value).toEqual([1])
 
     // custom function
     storage.setItem(KEY, JSON.stringify([{ a: 1 }]))
-    const customRef = useStorage(KEY, [{ a: 3 }], storage, { mergeDefaults: (value, initial) => ([...initial, ...value]) })
-    expect(JSON.stringify(customRef.value)).toBe(JSON.stringify([{ a: 3 }, { a: 1 }]))
+    const customRef = useStorage(KEY, [{ a: 3 }], storage, { mergeDefaults: (value, initial) => [...initial, ...value] })
+    expect(customRef.value).toEqual([{ a: 3 }, { a: 1 }])
+
+    // custom function 2
+    storage.setItem(KEY, '1')
+    const customRef2 = useStorage(KEY, 2, storage, { mergeDefaults: (value, initial) => value + initial })
+    expect(customRef2.value).toEqual(3)
   })
 })
diff --git a/packages/core/useStorage/index.ts b/packages/core/useStorage/index.ts
index 8f1abcbc06f..f2ca68b9e52 100644
--- a/packages/core/useStorage/index.ts
+++ b/packages/core/useStorage/index.ts
@@ -78,8 +78,8 @@ export interface UseStorageOptions<T> extends ConfigurableEventFilter, Configura
   /**
    * Merge the default value with the value read from the storage.
    *
-   * When setting to true, it will perform a shallow merge for objects/arrays.
-   * You can pass a custom merge function or deep merge.
+   * When setting it to true, it will perform a **shallow merge** for objects.
+   * You can pass a function to perform custom merge (e.g. deep merge), for example:
    *
    * @default false
    */
@@ -198,9 +198,9 @@ export function useStorage<T extends(string | number | boolean | object | null)>
         const value = serializer.read(rawValue)
         if (isFunction(mergeDefaults))
           return mergeDefaults(value, rawInit)
-        else if (type === 'object')
-          return Array.isArray(value) ? [...rawInit as any, ...value] : { ...rawInit as any, ...value }
-        return rawInit
+        else if (type === 'object' && !Array.isArray(value))
+          return { ...rawInit as any, ...value }
+        return value
       }
       else if (typeof rawValue !== 'string') {
         return rawValue