rtx + fish shell fails to launch the language server

[Defman21]

Environment

• Elixir & Erlang versions (elixir --version):

 Erlang/OTP 26 [erts-14.0.2] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [jit]

Elixir 1.15.4 (compiled with Erlang/OTP 26)

• Elixir Language Server version: 0.16.0
• Operating system: MacOS Ventura 13.5
• Editor or IDE name (e.g. Emacs/VSCode): VSCode
• Editor Plugin/LSP Client name and version: 0.16.0

Current behavior

Running /Users/defman/.vscode/extensions/jakebecker.elixir-ls-0.16.0/elixir-ls-release/launch.sh
Preffered shell fish is not supported, continuing in POSIX shell
Looking for ASDF install
ASDF not found
Looking for rtx executable
rtx executable found in /Users/defman/bin/rtx, activating
/Users/defman/.vscode/extensions/jakebecker.elixir-ls-0.16.0/elixir-ls-release/launch.sh: line 50: set: -g: invalid option
set: usage: set [--abefhkmnptuvxBCHP] [-o option] [arg ...]
[Error - 16:38:48] Server initialization failed.
  Message: Pending response rejected since connection got disposed
  Code: -32097 
[Error - 16:38:48] The ElixirLS - api server crashed 5 times in the last 3 minutes. The server will not be restarted. See the output for more information.
[Error - 16:38:48] ElixirLS - api client: couldn't create connection to server.
  Message: Pending response rejected since connection got disposed
  Code: -32097 
[Error - 16:38:48] Restarting server failed
  Message: Pending response rejected since connection got disposed
  Code: -32097 

I assume it fails because rtx activate $preferred_shell ( => rtx activate fish) outputs fish-style config, which is then eval'd by sh, thus failing.

[Defman21]

Current workaround: hardcode preferred_shell=bash at this line: https://github.com/elixir-lsp/elixir-ls/blob/master/scripts/launch.sh#L14

[lukaszsamson]

Fish is not supported and I think it never was. It shouldn’t be difficult to add support if anyone is willing to contribute.

[Defman21]

I assume the "support" in this context is "launch.sh" but in fish script? (e.g. if we detect that the preferred shell is fish, execute launch.fish instead). We can't simply relaunch the current script because it's not going to work in fish.

[lukaszsamson]

I'm not familiar with fish so it's hard to tell. Executing dedicated launch.fish would probably be a best option. The other is to force fallback to bash/zsh

[lukaszsamson]

A possible solution would be adding

    elif [ "$preferred_shell" = "fish" ]; then
      >&2 echo "Preferred shell is fish, relaunching"
      exec "$(which fish)" -c "$0 relaunch"

and

elif [ "$preferred_shell" = "fish" ]; then
  # in fish shell, convert ELS_ELIXIR_OPTS into a list and pass to elixir
  if [ -n "$ELS_ELIXIR_OPTS" ]
  then
    # Use fish to split ELS_ELIXIR_OPTS into a list and join them back into a space-separated string
    elixir_opts=$(fish -c "string join ' ' (string split ' ' \"$ELS_ELIXIR_OPTS\")")
  else
    elixir_opts=""
  fi
  exec elixir $elixir_opts --erl "$default_erl_opts $ELS_ERL_OPTS" "$SCRIPTPATH/launch.exs"

[Defman21]

I'll try the second option and if it doesn't work, I'll go with the first one (launch.fish).