test(runtime-core): improve test for #2295 (#2309)

packages/runtime-core/__tests__/rendererComponent.spec.ts

@@ -141,21 +141,32 @@ describe('renderer: component', () => {
  })
 
  // #2170
- test('should have access to instance’s “$el” property in watcher when rendereing with watched prop', async () => {
+ test('instance.$el should be exposed to watch options', async () => {
  function returnThis(this: any) {
  return this
  }
  const propWatchSpy = jest.fn(returnThis)
+ const dataWatchSpy = jest.fn(returnThis)
  let instance: any
  const Comp = {
  props: {
  testProp: String
  },
 
+ data() {
+ return {
+ testData: undefined
+ }
+ },
+
  watch: {
  testProp() {
  // @ts-ignore
  propWatchSpy(this.$el)
+ },
+ testData() {
+ // @ts-ignore
+ dataWatchSpy(this.$el)
  }
  },
 
@@ -172,10 +183,15 @@ describe('renderer: component', () => {
  render(h(Comp), root)
  await nextTick()
  expect(propWatchSpy).not.toHaveBeenCalled()
+ expect(dataWatchSpy).not.toHaveBeenCalled()
 
  render(h(Comp, { testProp: 'prop ' }), root)
  await nextTick()
  expect(propWatchSpy).toHaveBeenCalledWith(instance.$el)
+
+ instance.testData = 1
+ await nextTick()
+ expect(dataWatchSpy).toHaveBeenCalledWith(instance.$el)
  })
 
  // #2200