Several issues when filtering list from long to shorter (or short to longer)

Bug Report

Describe the Bug

Displaying a short list (81 entries) after a long list (830 entries) skips all but two (or a few) entries of shorter list and introduces excess free space before items displayed. resetScroll is enabled and itemCount managed as local state. This only happens when first (longer) list was scrolled down for a few pages.

How to Reproduce

Usage:

  const [itemCount, setItemCount] = React.useState(entries.length)
  const { outerRef, innerRef, items, scrollToItem } = useVirtual({
    itemCount,
    resetScroll: true
  })

  React.useEffect(() => {
    setItemCount(entries.length)
  }, [entries])

CodeSandbox Link

I’m working on a CodeSandbox which reproduces this behavior. This will take a few days.

Expected Behavior

Second (shorter) list is displayed with first entry at the top (provided resetScroll is working as intended).

Screenshots

Your Environment

• MacBook Pro (15-inch, 2017)
• macOS 11.5.2 (Big Sur)
• Electron 13.1.6

process.versions = {
  "node": "14.16.0",
  "v8": "9.1.269.36-electron.0",
  "uv": "1.40.0",
  "zlib": "1.2.11",
  "brotli": "1.0.9",
  "ares": "1.16.1",
  "modules": "89",
  "nghttp2": "1.41.0",
  "napi": "7",
  "llhttp": "2.1.3",
  "openssl": "1.1.1",
  "icu": "68.1",
  "unicode": "13.0",
  "electron": "13.1.6",
  "chrome": "91.0.4472.124"
}

Additional Information

N/A

[dehmer]

@wellyshen Thank you! Looks good so far. We will test extensively in the coming days. Fingers crossed! 🤞

[dehmer]

Yes. I slightly modified https://codesandbox.io/s/cocky-microservice-45702

Try this to reproduce issue 2:

1. filter: type ‘4c’
2. filter: cut ‘4c’
3. scroll to list bottom with cursor down key
4. filter: paste ‘4c’
5. filter: cut ‘4c’ expected: list shows some 80 entries actual: list shows only 7 entries