Faster pane navigation in tmux

[b0o]

The recommended tmux configuration for navigating panes is slower than it needs to be, because it's checking if a pane contains vim at the moment you press the keybinding to switch panes. This leads to a noticeable delay.

I wrote a script for tmux that runs in the background and periodically checks which panes contain vim and sets a pane-local option. Then, when you hit the keybinding to switch panes, tmux only needs to check for this option to determine what to do, rather than shelling out to ps and grep. With this approach, there is virtually no lag when switching panes.

You don't need to change your vim-tmux-navigator configuration at all to use it.

The script: https://github.com/b0o/tmux-conf/blob/main/navi.tmux

To install:

0. Save the script somewhere
1. Add this to the end of your tmux.conf: run-shell "$XDG_CONFIG_HOME/tmux/navi.tmux" (change the path to wherever you put the script)
2. Change your pane navigation bindings:

bind-key -n C-h if -F "#{@navi-state}" "send-keys C-h" "select-pane -LZ"
bind-key -n C-j if -F "#{@navi-state}" "send-keys C-j" "select-pane -DZ"
bind-key -n C-k if -F "#{@navi-state}" "send-keys C-k" "select-pane -UZ"
bind-key -n C-l if -F "#{@navi-state}" "send-keys C-l" "select-pane -RZ"

[mrjones2014]

Woah, this is cool!

Couldn't I theoretically have the plugin set the pane-local tmux option and unset it on nvim exit, so that the background script wouldn't be needed? I actually do something like that for Wezterm already.

smart-splits.nvim/plugin/smart-splits.vim

Lines 64 to 74 in 33c8507

	let s:are_we_wezterm = luaeval("require('smart-splits.utils').are_we_wezterm()")
	if s:are_we_wezterm
	call s:write(s:format_var("true"))
	" Set to false if nvim is suspended with ctrl+z
	autocmd VimSuspend * :call s:write(s:format_var("false"))
	" Set to true if nvim is resumed after being suspended with ctrl+z
	autocmd VimResume * :call s:write(s:format_var("true"))
	" Set to false when nvim exits
	autocmd VimLeave * :call s:write(s:format_var("false"))
	endif

This way the default out-of-the-box plugin configuration would have this improvement.

[b0o]

Yeah you could do this for sure, I recommend it!

[b0o]

It might be a good idea to pick a neutral name for the pane-local option, like @is-vim, so that other plugins like christoomey/vim-tmux-navigator could choose to adopt it as well.

Edit: I see that the wezterm var name is already plugin-neutral, so you are already doing it that way :)

[mrjones2014]

This is now the default implementation since #155, thank you for sharing!