bug: scrolling quickly can interfere with highlights

[ollien]

Check the following:

• I have checked the behavior after setting "vscode-neovim.neovimClean" in VSCode settings.
• I have read the vscode-neovim docs.
• I have searched existing issues.

Neovim version (nvim -v)

v0.9.5

Operating system/version

Fedora 39

Describe the bug

I admit, this one is a bit tough to reproduce, but I have managed to reproduce it. I originally thought this might be a bug with #1940, but I can reproduce it with master.

When you scroll quickly in a file, sometimes highlights are removed from the screen. I suspect there is somehow a race between our tracking of the viewport and the tracking of the highlights.

I found this bug, which was marked as a duplicate, but I could not find what it was marked as a duplicate of? #1833

Steps To Reproduce

1. Open a file that you are able to scroll significantly in
2. Search for text with /, and move your cursor to another line.
3. Scroll up and down quickly with your mouse, and notice highlights disappear

Here's a recording of me searching for /jest in https://github.com/jestjs/jest/blob/726ca20752e38c18e20aa21740cec7aba7891946/package.json. Keep your eye on line 1, and notice the highlight disappears.

recording-2024-05-07_21.22.25.mp4

Expected Behavior

The existence of the highlight should not depend on how quickly one scrolls

[xiyaowong]

If it's just that the highlighting takes a while to appear, that's expected. Scrolling must be debounced, so it's an unavoidable phenomenon.

vscode-neovim/src/viewport_manager.ts

Line 147 in 12e0d8b

private onDidChangeVisibleRange = async (e: TextEditorVisibleRangesChangeEvent): Promise<void> => {