How to discover correct configs for debugging over TRAMP (specifically Rust)

[bertulli]

Hi, first thank you for your work! I'm trying to set up dape to work with Rust programs, I remember doing it successfully a few months ago, but now I need to do the same connecting to a WSL machine. Specifically:

• Host machine: Windows 11, running Emacs GNU Emacs 29.2 (build 2, x86_64-w64-mingw32) of 2024-02-01
• Target machine: WSL Ubuntu-22.04, with installed codelldb as shown in the README, and exposing the ssh server on port 2020.

I usually can connect via TRAMP using the path /plink:[email protected]#2020:~/. After a bit of thinkering, I managed to customize the dape-config to

(codelldb-rust modes
		    (rust-mode rust-ts-mode)
		    ensure dape-ensure-command command "/plink:[email protected]#2020:~/.emacs.d/debug-adapters/codelldb/extension/adapter/codelldb" command-cwd dape-command-cwd :type "lldb" :request "launch" command-args
		    ("--port" :autoport "--settings" "{\"sourceLanguages\":[\"rust\"]}")
		    port :autoport :cwd "." :program
		    (lambda nil
		      (file-name-concat "target" "debug"
					(thread-first
					  (dape-cwd)
					  (directory-file-name)
					  (file-name-split)
					  (last)
					  (car))))
		    :args
		    []
		    :stopOnEntry nil)

(notice how I prefixed the command path with the TRAMP prefix). When launching dape, I insert the string codelldb-rust command-cwd "/plink:[email protected]#2020:~/exercism/rust/luhn/target/debug/" :program "luhn", and I obtain the error:

* Remote connection detected, setting prefix-local to "/plink:[email protected]:" *
* Unable to connect to dap server at localhost:0 *
* Connection is configurable by host and port keys *
env: ‘/plink:[email protected]#2020:/home/abertulli/.emacs.d/debug-adapters/codelldb/extension/adapter/codelldb’: No such file or directory

so I presume dape is not correctly detecting that the server is on a remote machine. Maybe it is similar to #109 or #105 , but I don't know which port I should specify. A couple of tries:

• codelldb-rust command-cwd "/plink:[email protected]#2020:~/exercism/rust/luhn/target/debug/" port 2020 :program "luhn"

* Remote connection detected, setting prefix-local to "/plink:[email protected]:" *
* Adapter connection shutdown without successfully initializing *
Configuration:
  modes (rust-mode rust-ts-mode)
  ensure dape-ensure-command
  command "/plink:[email protected]#2020:~/.emacs.d/debug-adapters/codelldb/extension/adapter/codelldb"
  command-cwd "/plink:[email protected]#2020:~/exercism/rust/luhn/target/debug/"
  :type "lldb"
  :request "launch"
  command-args ("--port" "2020" "--settings" "{\"sourceLanguages\":[\"rust\"]}")
  port 2020
  :cwd "."
  :program "luhn"
  :args []
  :stopOnEntry nil
  prefix-local "/plink:[email protected]:"
Invalid SSH identification string.

env: ‘/plink:[email protected]#2020:/home/abertulli/.emacs.d/debug-adapters/codelldb/extension/adapter/codelldb’: No such file or directory

• codelldb-rust command-cwd "/plink:[email protected]#2020:~/exercism/rust/luhn/target/debug/" :port 2020 :program "luhn"

* Remote connection detected, setting prefix-local to "/plink:[email protected]:" *
* Unable to connect to dap server at localhost:0 *
* Connection is configurable by host and port keys *
env: ‘/plink:[email protected]#2020:/home/abertulli/.emacs.d/debug-adapters/codelldb/extension/adapter/codelldb’: No such file or directory

So, which configuration should I change to make dape launch via TRAMP a remote debug server? In this case, everything resides on the target machine, the only thing external is Emacs. Should I do an ssh forwarding? But on which poort? Thanks!