fix(highlights): fix misaligned rendering in visual mode

[xiyaowong]

• Resolve incorrect col_start parameter in grid_line event due to tab synchronization issue.
• Resolve pseudo cursor rendering issue on tab.
• Resolve undesired Cursor highlight ranges.

fixes #1374, fixes #1144, fixes #1368

[theol0403]

Thanks for this!!

For the visual selection highlight, I opted to include it because there are some cases where neovim does not notify vscode that the visual selection has been updated. neovim/neovim#19708. I think this just smooths the edges and makes sure you always get some feedback that the visual selection has updated, albeit where the vscode selection will be temporarily incorrect.

Does this also fix the issue I found in #1144? I was able to reproduce the issue in terminal neovim, which was that when the "fake" visual cursor is on top of a tabstop character, it doesn't render the tabstop, messing up the highlighting. You probably just don't see the problem because you disabled visual highlight.

I'm not sure about the breaking test, it could be from unrelated changes/neovim update, or there could be some edge case you've uncovered.

Thanks for looking into this!

[xiyaowong]

@theol0403 Well, it's been a long day of debugging.

[theol0403]

Thanks for all the debugging!

Unfortunately, I don't think this fully solves any of the linked PRs.

I think that 0ebe821 (#1401) just hides the issues, but like I mentioned, the visual selection is still currently needed to provide visual feedback to actions like ciw.

I believe you've fixed a real bug, but I am still able to reproduce, with tabs and visual selection enabled, the issues.

[xiyaowong]

Well, I've reproduced these issues, too. That's sad

[xiyaowong]

@theol0403 All the issues I encountered so far have been fixed 🏃

[theol0403]

Great work, looks awesome!

[thessem]

Just wanna pop in to this PR and say this has significantly increased my quality of life. Thank you.