Smart-splits.nvim + Wezterm

[masoniis]

Does anyone else use Wezterm as their terminal emulator alongside this plugin? I noticed that on Wezterm there is a noticeable delay (maybe 500-1000ms) when performing a circular window navigation (and this doesn't appear when I switch to macOS default terminal).

I'm not sure if this is a fixable problem, or if it's just a result of the slowness of Wezterm itself when paired with the circular navigation.

[mrjones2014]

I do ✋

For me, though, the delay is the same whether it's the circular navigation or not. I think it is just due to the fact that the Wezterm keybinds require getting the foreground process name to detect if vim/nvim is running, which unfortunately can be an expensive operation as mentioned here: https://wezfurlong.org/wezterm/config/lua/PaneInformation.html

I'll keep thinking on if there is any other way to achieve this.

[mrjones2014]

The issue still persists with that commit, I built and tested locally. I think it may also be due to the Wezterm keybinds I'm using to support the integration, I think the docs said that pane:get_foreground_process_name() can be expensive?

local w = require('wezterm')

-- Equivalent to POSIX basename(3)
-- Given "/foo/bar" returns "bar"
-- Given "c:\\foo\\bar" returns "bar"
local function basename(s)
  return string.gsub(s, '(.*[/\\])(.*)', '%2')
end

local function is_vim(pane)
  local process_name = basename(pane:get_foreground_process_name())
  return process_name == 'nvim' or process_name == 'vim'
end

local direction_keys = {
  Left = 'h',
  Down = 'j',
  Up = 'k',
  Right = 'l',
  -- reverse lookup
  h = 'Left',
  j = 'Down',
  k = 'Up',
  l = 'Right',
}

local function split_nav(resize_or_move, key)
  return {
    key = key,
    mods = resize_or_move == 'resize' and 'META' or 'CTRL',
    action = w.action_callback(function(win, pane)
      if is_vim(pane) then
        -- pass the keys through to vim/nvim
        win:perform_action({
          SendKey = { key = key, mods = resize_or_move == 'resize' and 'META' or 'CTRL' },
        }, pane)
      else
        if resize_or_move == 'resize' then
          win:perform_action({ AdjustPaneSize = { direction_keys[key], 3 } }, pane)
        else
          win:perform_action({ ActivatePaneDirection = direction_keys[key] }, pane)
        end
      end
    end),
  }
end

return {
  keys = {
    -- move between split panes
    split_nav('move', 'h'),
    split_nav('move', 'j'),
    split_nav('move', 'k'),
    split_nav('move', 'l'),
    -- resize panes
    split_nav('resize', 'h'),
    split_nav('resize', 'j'),
    split_nav('resize', 'k'),
    split_nav('resize', 'l'),
  },
}

[wez]

querying process information can have high and highly variable latency. You could try hard-coding your is_vim function to always return true (or false) to see if the latency is better to confirm/deny that theory.

[mrjones2014]

Hm, that does not fix the issue. However, this change fixes the performance issue, but introduces a bug in the plugin:

function M.current_pane_id()
  -- local output = wezterm_exec({ 'list-clients', '--format=json' })
  -- local data = vim.json.decode(output)
  -- if #data == 0 then
  --   return nil
  -- end
  -- -- if more than one client, get the active one
  -- if #data > 1 then
  --   table.sort(data, function(a, b)
  --     return a.idle_time.nanos < b.idle_time.nanos
  --   end)
  -- end
  -- return data[1].focused_pane_id
  return vim.env.WEZTERM_PANE
end

[mrjones2014]

Created #53 from this discussion.

[masoniis]

Closing discussion due to fix in #53 🎉

[mrjones2014]

As noted in #53, a commit has been made to improve performance, make sure you are using a Wezterm build with this commit included to take advantage of it. It should be included in nightlies starting tomrrow.
wez/wezterm@96f1585

[wez]

wezterm nightlies with that change are already available!

[mrjones2014]

Oh nice, thanks!