Use tmux pane/window for external terminal

[Abh15h3k]

Currently i'm using alacritty as externalTerminal

dap.defaults.fallback.external_terminal = {
    command = '/opt/homebrew/bin/alacritty';
    args = {'-e'};
}

I use tmux on my main terminal (iterm2)
i was wondering if it was possible to use and split-pane as external terminal. i tried the following.

dap.defaults.fallback.external_terminal = {
    command = '/opt/homebrew/bin/tmux';
    args = {'split-pane'};
}

this works for most projects but for java projects with a big classpath it fails
i get Terminal exited with status 1

PS
the project which has the huge classpath is a project from work. so i can't share much details on it. if anyone has any suggestions please share

[Abh15h3k]

After a bit of tinkering a remembered that vscode put the class path to in an argfile and replaced -cp ... with @<path-to-argfile>
so i used a wrapper shell file with the following

tmux split-pane "$(python3 /tmp/argify.py "$@")"

argify.py

import sys

command = sys.argv[1:]
index = command.index("-cp")

f = open("/tmp/argfile", "w")
f.write(command[index])
f.write(" ")
f.write(command[index+1])
f.close()

del command[index]
command[index] = "@/tmp/argfile"

print(' '.join(command))

with this wrapper (or double wrapper?) the project runs.
any suggestions to make it cleaner ?

[mfussenegger]

java-debug supports a shortenCommandLine option which can be set to jarmanifest or argfile. That might help avoid your custom script.

[Abh15h3k]

java-debug supports a shortenCommandLine option which can be set to jarmanifest or argfile. That might help avoid your custom script.

how would i set the option?
nevermind. it goes in the launch configuration.

Thanks for the help!

[Abh15h3k]

thanks to @mfussenegger

dap.configurations.configurations.java = {
    {
        ...
        shortenCommandLine = "argfile",
        ...
    }
}

same can be use while running test cases. just add the config while calling the api
lua require'jdtls'.test_nearest_method({config = {shortenCommandLine="argfile"}})

one caveat. if your test cases are path dependent (my work project loads some json files into mongodb using relative paths). you will have to enusre that the "terminal" starts at the correct root directory for tmux i do

dap.defaults.fallback.external_terminal = {
	command = "tmux",
	args = { "split-pane", "-c", "<desired-root-dir>"},
}

[Abh15h3k]

@mfussenegger is it possible to use the shortenCommandLine while running test cases via lua require'jdtls'.test_nearest_method() ? i get the same issue.

i used dap.defaults.fallback.force_external_terminal = true to force externalTerminal

[Abh15h3k]

figured it out. added to the answer

[AskaJohnny]

I have a problem when I use Telescope my dapui disappears, and then I can't connect to the original integrated terminal.

[AskaJohnny]

@mfussenegger Big guy I started the dap first and then used the telescope to locate the other file, and when I jumped to the other file, my original dapui disappeared, I opened it via dap.open, but dap-teminal couldn't connect to the previous one, including the dap ui scope also disappeared