Open R console in a new tmux pane

[MiboraMinima]

I am trying to configure the plugin to launch R in a new tmux pane within the same terminal. I've attempted the following configuration:

external_term = "tmux split-window 'R'"

This config successfully opens a new tmux pane when I start R.nvim and I can write R code in it. However, I am unable to send code from Neovim to the new pane. Additionally, the plugin doesn't function correctly, displaying the message "R is not ready yet" in Neovim when I attempt to run any command linked to R.nvim.

When I start R in the new pane, I see the following output:

ARGUMENT 'new-session' __ignored__

ARGUMENT 'Rnvim-551' __ignored__

ARGUMENT 'RNVIM_TMPDIR=/dev/shm/R.nvim-user' __ignored__

ARGUMENT 'RNVIM_COMPLDIR=/home/user/.cache/R.nvim' __ignored__

ARGUMENT 'RNVIM_ID=2930209553' __ignored__

ARGUMENT 'RNVIM_SECRET=2372621146' __ignored__

ARGUMENT 'RNVIM_PORT=10101' __ignored__

ARGUMENT 'R_DEFAULT_PACKAGES=datasets,utils,grDevices,graphics,stats,methods,nvimcom' __ignored__

ARGUMENT 'R' __ignored__

When I set config_tmux = true, the pane opens and closes immediately. If I set config_tmux = false, the pane stays open but nothing works as expected. The same messages are displayed in both cases.

Additional Information:

• I use Kitty as my terminal emulator.
• When I run the tmux split-window 'R' command directly from a terminal (not from within Neovim), it works perfectly.

Is it possible to open an R console in a new tmux pane, as the plugin seems to have been designed to open it in a new terminal ?

[PMassicotte]

have you simply tried:

external_term = "tmux split-window -vf ",

[jalvesaq]

Great, @PMassicotte! I didn't know that it was so simple!

[statquant]

This is great thanks for this !

[MiboraMinima]

It works perfectly ! Thank you !

[PMassicotte]

Maybe add this info in the help?

[jalvesaq]

Yes, it's a good idea to add it. Something like:

diff --git a/doc/R.nvim.txt b/doc/R.nvim.txt
index 04316cd..b402bd0 100644
--- a/doc/R.nvim.txt
+++ b/doc/R.nvim.txt
@@ -128,7 +128,8 @@ Suggestions for Unix (Linux, OS X, etc.):

    Tmux >= 3.0:  http://tmux.sourceforge.net
                  Tmux is required only if you want to run R in an external
-                 terminal emulator (see |external_term|).
+        terminal emulator or in a Tmux split panel
+        (see |external_term|).

    colorout:     https://github.com/jalvesaq/colorout/releases
                  Colorizes the R output in terminal emulators.
@@ -889,6 +890,11 @@ complete command to run the terminal. Examples:
 Please, look at the manual of your terminal emulator to know how to call it.
 The last argument must be the one which precedes the command to be executed.

+Although the option is intended to allow running R in an external terminal
+emulator, it can also be used to run R in a Tmux split panel. Example:
+>lua
+   external_term = "tmux split-window -vf "
+<
 The terminal error messages, if any, are shown as warning messages, unless you
 put in your config:
 >lua

[PMassicotte]

Excellent!

[johngodlee]

I receive an error when trying to run this with a minimal config taken from the R.nvim README.md. I'm running macOS Sonoma 14.5.

The error:

Vim:E482: Can't open file /var/folders/z6/k42yf16d3kj553t0r92j6vyr0000gn/T/nvim.johngodlee/oJeYzK/0/openR for writing: no such file or directory
stack traceback:
^I[C]: in function 'writefile'
^I...ee/.local/share/nvim/lazy/R.nvim/lua/r/external_term.lua:165: in function 'start_extern_term'
^I...s/johngodlee/.local/share/nvim/lazy/R.nvim/lua/r/run.lua:160: in function <...s/johngodlee/.local/share/nvim/lazy/R.nvim/lua/r/run.lua:16>

The config:

init.lua:

require("config.lazy")

lua/config/lazy.lua:

-- lazy.nvim boilerplate
local lazypath = vim.fn.stdpath("data") .. "/lazy/lazy.nvim"
if not vim.loop.fs_stat(lazypath) then
        vim.fn.system({
                "git",
                "clone",
                "--filter=blob:none",
                "https://github.com/folke/lazy.nvim.git",
                "--branch=stable", -- latest stable release
                lazypath,
        })
end
vim.opt.rtp:prepend(lazypath)

-- load lazy
require("lazy").setup("plugins")

lua/plugins/r.lua:

The config is the same as in the R.nvim README.md, save for these additional lines:

    config = function()
            local opts = {
                    external_term = "tmux split-window -vf "
            }

Full config:

return {
  {
    "R-nvim/R.nvim",
    config = function()
            local opts = {
                    external_term = "tmux split-window -vf "
            }
            require("r").setup(opts)
    end,
    lazy = false
  },
  {
    "nvim-treesitter/nvim-treesitter",
    run = ":TSUpdate",
    config = function ()
      require("nvim-treesitter.configs").setup({
        ensure_installed = { "markdown", "markdown_inline", "r", "rnoweb" },
      })
    end
  },
  "R-nvim/cmp-r",
  {
    "hrsh7th/nvim-cmp",
    config = function()
      require("cmp").setup({ sources = {{ name = "cmp_r" }}})
      require("cmp_r").setup({ })
    end,
  },
}

[jalvesaq]

The problem is that macOS doesn't open whatever terminal emulator users choose and our solution is to open a shell script. This causes the default terminal emulator to be opened by macOS. So, we have to create an exception if the "terminal" is tmux.

Line 157 of lua/r/external_term.lua is:

    if config.is_darwin then

I don't have a macOS to try any changes, but, perhaps, it would work if line 157 were:

    if config.is_darwin and not term_cmd:find("^tmux ") then

[jalvesaq]

Or:

    if config.is_darwin and term_name ~= "tmux " then

[johngodlee]

Hi @jalvesaq thanks for the prompt reply. I tried both your suggestions, but neither worked.

The first suggestion complains that term_cmd is not set:

...ee/.local/share/nvim/lazy/R.nvim/lua/r/external_term.lua:157: attempt to index upvalue 'term_cmd' (a nil value)

The second fails with the same message as when no changes are applied.

Thanks for the headstart though, I will continue to think about how this can be fixed.

[jalvesaq]

Maybe it will be fixed if we change the position of line 20. Instead of:

    if config.is_darwin then return end

    if type(config.external_term) == "string" then
        -- User defined terminal
        term_name = string.gsub(tostring(config.external_term), " .*", "")
        if string.find(tostring(config.external_term), " ") then
            -- Complete command defined by the user
            term_cmd = config.external_term
            return
        end
    end

It would be:

    if type(config.external_term) == "string" then
        -- User defined terminal
        term_name = string.gsub(tostring(config.external_term), " .*", "")
        if string.find(tostring(config.external_term), " ") then
            -- Complete command defined by the user
            term_cmd = config.external_term
            return
        end
    end

    if config.is_darwin then return end

[johngodlee]

When I combine the suggested move of L20 with this change to L157:

    if config.is_darwin and not term_cmd:find("^tmux ") then

everything works as expected! Thank you so much for your help.

Will it be possible to add these changes to the next release, or is there still a lot of testing to make sure these changes don't break other stuff?

[jalvesaq]

I can do the changes on the main branch. But, instead of not term_cmd:find("^tmux "), it's simpler to test term_name ~= "tmux" (there was a trailing space in my comment above).

[PMassicotte]

Maybe it will be fixed if we change the position of line 20. Instead of:

    if config.is_darwin then return end

    if type(config.external_term) == "string" then
        -- User defined terminal
        term_name = string.gsub(tostring(config.external_term), " .*", "")
        if string.find(tostring(config.external_term), " ") then
            -- Complete command defined by the user
            term_cmd = config.external_term
            return
        end
    end

It would be:

    if type(config.external_term) == "string" then
        -- User defined terminal
        term_name = string.gsub(tostring(config.external_term), " .*", "")
        if string.find(tostring(config.external_term), " ") then
            -- Complete command defined by the user
            term_cmd = config.external_term
            return
        end
    end

    if config.is_darwin then return end

Good catch!

[jalvesaq]

I pushed the changes to the main branch and it should work on macOS now... Thanks for reporting the issue and for the feedback!

[mpadge]

Quick question here as a related sub-issue for @jalvesaq and/or @PMassicotte: The new tmux pane for me now only scrolls back to top of visible buffer but not further, using tmux scroll Ctrl-[ + Ctrl-B. This occurs regardless of whether I use my custom tmux.conf or not (via config_tmux). My config is here. Any help would be appreciated! And thanks for all of your awesome work!

[PMassicotte]

What is your history-limit?

Maybe you can increase it with something like:

echo "set -g history-limit 5000" >> ~/.tmux.conf

I am a kitty user now, so might not be the right way :)

[mpadge]

Thanks @PMassicotte, but it's not that. I use huge history limits, and it's very clearly related to screen buffer not history itself. This is in alacritty, not kitty. Any other ideas?

[jalvesaq]

Tmux is running inside Tmux, so you have to press <C-A> twice and then [ to enter the copy mode in the nested Tmux.

[jalvesaq]

Since running R in a Tmux split pane is a recurrent demand, I'll try to make it work better.

[jalvesaq]

On the branch https://github.com/R-nvim/R.nvim/tree/tmux_split, R.nvim directly splits Tmux window instead of running a nested Tmux instance.