Tab activity indicator

[anongit]

In iTerm2 there is a built-in option to show that there was new output in an inactive tab:

Is there an easy way to configure this?
I guess you could make it with user vars and monitoring tabs / panes in format-tab-title, but it seems like a hack.

[wez]

We don't have this today, but adding support for it is doable. In my mind this overlaps a bit with #3

[anongit]

Thanks, subscribed to that issue.

[hoverduck]

I hacked this together with uservars and a bash script that you pipe your log output into. So it won't work as something you could turn on ad-hoc for an existing long-running process, but for my use case of keeping a tail on a log file it works great.

It works with tail -f somefile.log | wezterm-tail-alert.sh, which just reads and echos each line, and both prints out a UserVar named lastOutput with the current timestamp and rings the system bell. For any tab with lastOutput set, the format-tab-title event keeps track of the last time I had that as my active tab, and if the timestamp of lastOutput is greater than lastVisit it adds (!) to the pane title and turns it red.

Separately in the bell event I'm tracking the last line of output on those tabs, so I can ignore any log output that matches a given string (basically in my use case I want to ignore Info output and only be alerted on Warning/Fatal). I could also imagine building off of that to change the tab color for warnings, or send a toast notification for fatals. But that gets really application-specific.

This is the most I've ever written in Lua, so happy to know if there's an easier way to do any of this.

wezterm-tail-alert.sh:

#!/bin/bash

while read line; do
        echo $line
        printf "\e]1337;SetUserVar=%s=%s\a" lastOutput $(date +'%s'| base64)
        tput bel
done

local wezterm = require 'wezterm';
local lastVisits = {};
local lastLines = {};

wezterm.on("format-tab-title", function( tab, tabs, panes, config, hover, max_width )
  local pane_title = tab.active_pane.title
  local lastOutput = tonumber( tab.active_pane.user_vars.lastOutput )
  local currTime = tonumber( wezterm.strftime("%s") )
  local index = tonumber( tab.tab_index )+1
  local format = {}

  if lastOutput ~= nil then
    if lastVisits[ tab.tab_id ] == nil then
      lastVisits[ tab.tab_id ] = currTime
    end

    if lastOutput > lastVisits[ tab.tab_id ] then
      i, j = string.find( lastLines[ tab.active_pane.pane_id ], "INFO:" )
      if nil == i then
        pane_title = "(!) " .. pane_title
	table.insert( format, { Foreground={Color="Red"} } )
      end
    end

    if tab.is_active and lastVisits[ tab.tab_id ] < currTime then
      lastVisits[ tab.tab_id ] = currTime
    end
  end

  table.insert( format, { Text=index .. ": " .. pane_title } )
  return format
end)

-- https://www.codegrepper.com/code-examples/lua/lua+split+string+by+delimiter
function Split(s, delimiter)
    result = {};
    for match in (s..delimiter):gmatch("(.-)"..delimiter) do
        table.insert(result, match);
    end
    return result;
end

wezterm.on("bell", function(window, pane)
  local lastOutput = tonumber( pane:get_user_vars().lastOutput )
  if lastOutput ~= nil then
    local lines = Split( pane:get_logical_lines_as_text(), "\n" )
    lastLines[ pane:pane_id() ] = lines[ #lines ]
  end
end)

return {}

[wez]

Thanks for sharing this! You motivated me to hook something up in wezterm itself.
0bf1b8d allows for this:

local wezterm = require 'wezterm'

wezterm.on("format-tab-title", function(tab, tabs, panes, config, hover, max_width)
  if tab.is_active then
    return {
      {Background={Color="blue"}},
      {Text=" " .. tab.active_pane.title .. " "},
    }
  end
  local has_unseen_output = false
  for _, pane in ipairs(tab.panes) do
    if pane.has_unseen_output then
      has_unseen_output = true
      break;
    end
  end
  if has_unseen_output then
    return {
      {Background={Color="Orange"}},
      {Text=" " .. tab.active_pane.title .. " "},
    }
  end
  return tab.active_pane.title
end)

return {
}

I need to write up docs around this but have to run now; I'll come back to it later.

Briefly, things to note:

• First, just wanted to note that spawning a new tab doesn't tell the old tab it lost focus, but switching back and forth works fine. Will fix this later.
• I added has_unseen_output field to PaneInformation and a pane:has_unseen_output() method to tell if there has been output in a pane since it last lost focus.
• I added an event that allows unseen output to signal the gui to update the title bar so that format-tab-title will be triggered
• Nuanced behavior: format-tab-title's panes parameter is only ever the list of panes for the active tab, even when the current tab is no the active tab. Will need to think about whether this should be changed to match the current tab in a future release.
• Meanwhile, I added a panes field to TabInformation to get the pane information list for that tab, so that there is a way to access that info

The example above shows how to iterate the panes in a tab to see if any of them have unseen output. For an inactive tab with unseen output, the tab color is set to orange.

You should be able to download a nightly build with these changes within an hour of this comment being posted.

[hoverduck]

Phenomenal! I'll check the nightly build out later today :)

[hoverduck]

I checked out the nightly build last night and the new tab activity feature works great! Unfortunately for me I also ran into too many issues with my key maps on Colemak (I assume because of #1483) so I reverted back to the stable release for now. But I'll switch back to nightly when I have more time to play with it and figure out what's going on :)

[madhur]

Are we going to roll out this feature?

[wez]

It shipped over a year ago already in https://wezfurlong.org/wezterm/changelog.html#20220319-142410-0fcdea07

[sandeep-ad]

Could you please make it look like Tmux where tab name does not change with cwd and where pressing leader key and comma allows to rename tab title.