When enabling cursorline, it only underlines text rather than the whole line on screen

[rex-ludorum]

Problem

In my .vimrc, I have

set cursorline
hi clear CursorLine
hi CursorLine gui=underline cterm=underline

to enable underlining. In Vim, this underlines the whole line in the screen as expected, even without whitespace trailing the text:

However, in Neovim (my nvim setup sources my .vimrc), this only underlines the portion of the line with text along with leading whitespace:

Rarely, it doesn't underline leading indentations or manages to underline the rest of the line. I have no clue what the criteria for these cases are:

Moreover, this is only a problem on Windows, where I have nvim installed on msys through pacman. On Ubuntu with the same config, the whole line is always underlined:

I'd like to have neovim on Windows behave consistently with Ubuntu and underline the whole line.

Steps to reproduce

See above

Expected behavior

The whole line should be underlined, not only the portion with text.

Neovim version (nvim -v)

0.9.2

Vim (not Nvim) behaves the same?

no, 9.0.1976

Operating system/version

Windows 10

Terminal name/version

mintty 3.6.5

$TERM environment variable

xterm-256color

Installation

pacman on msys2
pacman -S mingw-w64-ucrt-x86_64-neovim

[justinmk]

Latest stable release is 0.9.4, not 0.9.2. Also try the prerelease https://github.com/neovim/neovim/releases/tag/nightly .

Terminal name/version : mintty 3.6.5

Does it happen if with cmd.exe or Windows terminal ?

[rex-ludorum]

I updated to 0.9.4 and tried the prerelease and the problem persists. Running nvim in cmd or Windows Terminal fixes it though.

[rex-ludorum]

I tried installing my setup on a different Windows 11 computer and the problem is fixed on there. The problem only happens on my Windows 10 computer.

[justinmk]

Then this is likely a terminal issue and not going to to spend time adding a workaround.

[mintty]

nvim was logged to send wrong escape sequences in the documented scenario:
mintty/mintty#1239 (comment)

[zeertzjq]

@rex-ludorum Do you have infocmp command available in MSYS2? Try searching and installing some packages containing ncurses in their names if infocmp is not present. If infocmp is available, what does infocmp -Lx print in mintty?

[mintty]

infocmp does not depend on the terminal, it only considers $TERM
I've tried to vary on xterm-256color etc already.

[zeertzjq]

Yes, but I don't get \x1b[16X or \x1b[m in XTerm. What I get is 16 spaces and \x1b[0;4m.

With syntax:

\x1b(B\x1b[0;4m                \x1b(B\x1b[0;4m\x1b[93mwhile\x1b(B\x1b[0;4m ((bytes_read = read(\x1b(B\x1b[0;4m\x1b[95mSTDIN_FILENO\x1b(B\x1b[0;4m, buf, SEND_BUFFER_SIZE)) > \x1b(B\x1b[0;4m\x1b[95m0\x1b(B\x1b[0;4m) {                                                                                                         

Without syntax:

\x1b(B\x1b[0;4m                while ((bytes_read = read(STDIN_FILENO, buf, SEND_BUFFER_SIZE)) > 0) {                                                                                                         

[rex-ludorum]

I do have it installed. infocmp -V gives ncurses 6.4.20221231.

infocmp -Lx gives infocmp-out.txt

[zeertzjq]

Hmm, that's also the same as the terminfo of XTerm on Linux, so it's really strange that these sequences are quite different from what I get in XTerm.