test(watch): sync with vue

vuejs/core#13434

Author: yangmingshan

packages/core/__tests__/watch.spec.ts

@@ -994,6 +994,57 @@ describe('watch', () => {
     expect(cb).toHaveBeenCalledTimes(4)
   })
 
+  test('watching the same object at different depths', async () => {
+    const arr1: any[] = reactive([[[{ foo: {} }]]])
+    const arr2 = arr1[0]
+    const arr3 = arr2[0]
+    const obj = arr3[0]
+    arr1.push(arr3)
+
+    const cb1 = vi.fn()
+    const cb2 = vi.fn()
+    const cb3 = vi.fn()
+    const cb4 = vi.fn()
+    watch(arr1, cb1, { deep: 1 })
+    watch(arr1, cb2, { deep: 2 })
+    watch(arr1, cb3, { deep: 3 })
+    watch(arr1, cb4, { deep: 4 })
+
+    await nextTick()
+    expect(cb1).toHaveBeenCalledTimes(0)
+    expect(cb2).toHaveBeenCalledTimes(0)
+    expect(cb3).toHaveBeenCalledTimes(0)
+    expect(cb4).toHaveBeenCalledTimes(0)
+
+    obj.foo = {}
+    await nextTick()
+    expect(cb1).toHaveBeenCalledTimes(0)
+    expect(cb2).toHaveBeenCalledTimes(0)
+    expect(cb3).toHaveBeenCalledTimes(1)
+    expect(cb4).toHaveBeenCalledTimes(1)
+
+    obj.foo.bar = 1
+    await nextTick()
+    expect(cb1).toHaveBeenCalledTimes(0)
+    expect(cb2).toHaveBeenCalledTimes(0)
+    expect(cb3).toHaveBeenCalledTimes(1)
+    expect(cb4).toHaveBeenCalledTimes(2)
+
+    arr3.push(obj.foo)
+    await nextTick()
+    expect(cb1).toHaveBeenCalledTimes(0)
+    expect(cb2).toHaveBeenCalledTimes(1)
+    expect(cb3).toHaveBeenCalledTimes(2)
+    expect(cb4).toHaveBeenCalledTimes(3)
+
+    obj.foo.bar = 2
+    await nextTick()
+    expect(cb1).toHaveBeenCalledTimes(0)
+    expect(cb2).toHaveBeenCalledTimes(1)
+    expect(cb3).toHaveBeenCalledTimes(3)
+    expect(cb4).toHaveBeenCalledTimes(4)
+  })
+
   test('pause / resume', async () => {
     const count = ref(0)
     const cb = vi.fn()