activePostFlushCbs is null

[ybom77]

Version

3.0.0-rc.7

Reproduction link

https://jsfiddle.net/ybom77/u243peaf/1/

Steps to reproduce

What is expected?

there should be no error in console

What is actually happening?

console:Uncaught TypeError: Cannot read property 'length' of null

what I find the reason for this error is the activePostFlushCbs is null

[peng]

I think you write a wrong way.

[HcySunYang]

I tracked the issue and this test case can reproduce it:

  test('flushPostFlushCbs', async () => {
    let count = 0
    const mounted1 = () => {
      renderJob(mounted2)
    }
    const mounted2 = () => {
      count++
    }
    const renderJob = (hook: Function) => {
      queuePostFlushCb(hook)
      flushPostFlushCbs()
    }

    renderJob(mounted1)
    await nextTick()
    expect(count).toBe(1)
  })

I’m not sure if this is a valid use case, if it’s valid, maybe we shouldn’t just set the value of activePostFlushCbs to null: https://github.com/vuejs/vue-next/blob/master/packages/runtime-core/src/scheduler.ts#L172

[zhigui]

Face the same problem. Some use cases like Tiptap.

🤔 related issue: #1595 (comment)

[yyx990803]

Note 53ed991 is a partial commit (I forgot to save the file when committing)

Proper fix commit is 36fa42a