fix(toRefs): keep class prototype, close #1530 (#1599)

Co-authored-by: nikitamihailov <mikhaylovnv.dev@gmail.com>

packages/core/useVModel/index.test.ts

@@ -155,4 +155,26 @@ describe('useVModel', () => {
     expect(dataD.value).toBe(null)
     expect(dataE.value).toBe('default-data')
   })
+
+  it('Should work with classes', async () => {
+    const emitMock = vitest.fn()
+
+    class SomeClass {
+      num1 = 1
+
+      someMethod() {}
+    }
+
+    const props = { cl: new SomeClass() }
+
+    const ref = useVModel(props, 'cl', emitMock, { passive: true, deep: true })
+
+    ref.value.num1 = 10
+
+    await nextTick()
+
+    const emitValue = (emitMock as any).calls[0][1]
+
+    expect(emitValue instanceof SomeClass).toBeTruthy()
+  })
 })

packages/shared/toRefs/index.test.ts

@@ -96,4 +96,22 @@ describe('toRefs', () => {
     refs[1].value = 1
     expect(spy).toHaveBeenLastCalledWith(['a', 1])
   })
+
+  it('should save instance of class', () => {
+    class SomeClass {
+      v = 1
+
+      fn() {
+
+      }
+    }
+
+    const obj = ref(new SomeClass())
+
+    const { v } = toRefs(obj)
+
+    v.value = 10
+
+    expect(obj.value instanceof SomeClass).toBeTruthy()
+  })
 })

packages/shared/toRefs/index.ts

@@ -31,7 +31,11 @@ export function toRefs<T extends object>(
           objectRef.value = copy
         }
         else {
-          objectRef.value = { ...objectRef.value, [key]: v }
+          const newObject = { ...objectRef.value, [key]: v }
+
+          Object.setPrototypeOf(newObject, objectRef.value)
+
+          objectRef.value = newObject
         }
       },
     }))