vimtex breaks v_g_CTRL-G

[brianbuccola]

v_g_CTRL-G allows you to select some text and then see some basic info about your selection, such as how many words you've selected.

Loading vimtex breaks this functionality: pressing v_g_CTRL-G seems to very quickly print the relevant info, but then it immediately disappears, way too quickly to read what it says.

I can confirm that after disabling vimtex, there is no issue.

1. A minimal vimrc file:

   set nocompatible
   let &rtp  = '~/.vim/bundle/vimtex,' . &rtp
   let &rtp .= ',~/.vim/bundle/vimtex/after'
   filetype plugin indent on
   syntax enable
   

2. A minimal mwe.tex file:

   \documentclass{minimal}
   \begin{document}
   Hello World!
   \end{document}
   

3. Run vim -u vimrc mwe.tex, visually select the word Hello, and press g_CTRL-G.

   • Expected behavior: Print the following for at least a few seconds.

     Selected 1 of 4 Lines; 1 of 5 Words; 5 of 70 Bytes
     

   • Actual behavior: Info disappears immediately.

[andymass]

I believe this is caused by the 50ms popup menu check timer. With the MWE you can call timer_stop(1) to verify the behavior goes away. I guess timers clear certain messages even when they don't do anything. For a few reasons, match-up never seemed to have the issue #493 which led to that hack and does not require a constant timer.

A possible workaround is to use my plugin match-up for the purpose of highlighting matches instead of vimtex's built-in one (see discussion here), although I admit it has much greater effects than just this, so it's not appropriate for everyone.

[lervag]

Interesting. I think @andymass is correct that this happens because of a timer loop. I think @andymass's plugin is good, and so it is a viable choice to use that instead of vimtex's built in match highlighter.

[lervag]

I've added the minimal example. I can confirm the bug with Vim, but it works as expected in neovim. I also confirm that the problem is due to the timer, regardless of what the timer callback actually does.

My understanding is that this is a bug in Vim internals, not with vimtex. There are two working "solutions": Use neovim or use @andymass's plugin. I will not be able to solve this bug myself, and so I am deciding to close the issue as won't fix. Sorry, and I hope someone might create a minimal example and open an issue with the Vim devs.

[brianbuccola]

Thanks, both. matchup looks like a very nice plugin, which I hadn't known about. I've just switched over.

[lervag]

No problem, and I'm sorry about the minor inconvenience.

[brianbuccola]

I've found that when using matchup, my cursor movement is seriously delayed, even on a relatively small paper (6 page report), and even after adding

let g:matchup_matchparen_deferred = 1

So, I think I will just stick with vimtex's built-in matching, and if I need v_g_CTRL-G, I will just

call timer_stop(1)

or maybe make a keybinding that toggles

call timer_pause(1, 1)

and

call timer_pause(1, 0)

or something.

[lervag]

A third option is to switch to neovim, where it seems everything works as expected.

[brianbuccola]

True. I may at some point, but just don't have the time right now -- too many projects that need finishing without any major disruption/change in my workflow. Perhaps in August, once things settle down a bit.

Anyway, thanks again.

[lervag]

No problem. I hope things work out well.

[lervag]

I've updated to use TextChangedP when possible, since this should improve the latency somewhat (I think) and avoid running the callback loop in the background when idle. I think this should also solve the present issue as long as you use a recent Vim version.

[brianbuccola]

Can confirm this resolves the issue -- thanks!