Vim cursor skips forward on single-letter replace

[LRitzdorf]

Windows Terminal version (or Windows build number)

WT v1.9.1942.0; MS Windows v10.0.19043.1110

Other Software

VIM - Vi IMproved 8.2 (2019 Dec 12, compiled May 2 2021 22:02:47)
64-bit console version for Windows, downloaded from https://github.com/vim/vim-win32-installer/releases/tag/v8.2.2825#:~:text=Signed%2064-bit%20installer. Patch version 2825.

Powerline v2.7 (Python3). powerline-status module, installed via pip.
This is not likely to be related to the issue, but I thought I'd include it nonetheless.

Steps to reproduce

• Open vim. Of the following, set t_EI and either of the t_S* variables:

let &t_EI .= "\<Esc>[1 q"
let &t_SR .= "\<Esc>[3 q"
let &t_SI .= "\<Esc>[5 q"

• Trigger single-letter replacement mode by pressing r.
• The cursor jumps forward, by five characters in my case.

Expected Behavior

The cursor should not jump forward when single-letter replacement mode is triggered.

Actual Behavior

The cursor jumps forward, as noted above.

Note that I've tested this same combination of factors in WSL Vim, and the jump does not occur.

[zadjii-msft]

I've tested this same combination of factors in WSL Vim, and the jump does not occur.

Ooooh. That's a good observation. The issue might have a root cause in Win32 Vim's VT parser. @DHowett will take a look.

[DHowett]

This is unfortunately a vim issue.

When it is printing the t_SR value to the screen (and t_SI!), it's dumping the escape characters directly to the screen without letting us parse them. Here's what it looks like in the console host:

This likely stems from the fact that vim.exe does not support escape sequences on Windows. When it is connected to Terminal, they accidentally work. This is only an accident -- vim has not put the console in the correct mode to handle this. As a result, though, the cursor virtually moves over to cover the raw sequence (as it should.)

The real bug is unfortunately that Terminal doesn't handle it like Console does.

[LRitzdorf]

Rats, that's unfortunate. Thanks for the information, though!

[alexeicolin]

UPDATE: issue fixed in vim 9.0.

P.S. Related issue of restoring cursor when exiting vim back into PowerShell, solved using this solution: add to PowerShell profile:

function vim {
        & "C:\Program Files (x86)\Vim\vim82\vim.exe" $args && echo "`e[5 q"
}