bug: `diff` children, the vnodes can includes `null` node

Describe the bug A clear and concise description of what the bug is.

so, the element can be removed, it’s not work as excepted.

if we filter the vnodes in my demo, it work perfect.

but, this causes the order of vnodes to be out of order, i try to find a nother way to resolve it. what’s your opinion? To Reproduce Steps to reproduce the behavior:

1. Go to ‘…’
2. Click on ‘…’
3. Scroll down to ‘…’
4. See error

Expected behavior A clear and concise description of what you expected to happen.

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Device (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Additional context Add any other context about the problem here.

[aidenybai]

I’ll be adding some more fixed to this PR to fix #203 – expect a merge by the end of this week!

[aidenybai]

I see, I’ll make some changes and merge your PR. Thanks for the explanation