Extension seems to not start in VSCode remote container (devcontainer)

[altdsoy]

Hello,
I am running my Elixir project within a container using VS Code remote container extension (devcontainer) with the ElixirLS extension.
I wanted to try NextLS... However, I can't get it working.
I checked in the troubleshooting section but was not able to find anything obvious..
The integrated terminal output I have for is not labeled Next LS but elixir-tools.vscode (not sure if this is relevant)..
And I only have the following log:
[info] files: undefined..
Also epmd is running..
I can't find anything in there ~/.cache/elixir-tools/nextls/bin/ which is the default value of the Installation Directory setting..
But it seems the extension is installed here ~/.vscode-server/extensions/elixir-tools.elixir-tools-0.15.1/bin
I tried to change the Installation Directory setting to this but without success..

What do I do wrong?
I'm running in Alpine Linux fwiw..

[mhanberg]

[info] files: undefined..

this log is showing that it couldn't find a mix.exs file in the root of the project.

there might be something related to the remote container extension that i'm not accounting for, will need some investigation

[altdsoy]

Well.. This is true as my Elixir Project is not in the root directory.. So I guess there's no equivalent of ElixirLS.projectDir option then?
Do I need to open VS Code in that sub-directory?

Actually I may have introduced some XY problem and here is my real question (sorry)..

My root folder is a poncho directory with a few apps, each within their own sub-directory...
I simply assumed ElixirLS was not able to handle poncho apps so I naively tried NextLS thinking maybe it'll just works...
But I guess, there is the same limitation here?

[mhanberg]

can you try and open each sub directory as a workspace folder?

I think you can quickly test this with code --add path/to/app1 --add path/to/app2 --new-window

[altdsoy]

Okay because the way each VS Code windows is tied to a running container I had to still open my root directory as it contains the related files for the devcontainer settings..
But I added one of the child app folder into the workspace..
It seems this time it triggered the installation of the last NextLS etc.
But I was still getting errors when I wanted to just start with formatting an Elixir file:
Request textDocument/formatting failed.
It seems it was still trying to do stuff in the initial root workspace..

So I removed as well that initial root workspace and with only one workspace dir (that has the mix.exs file at its root) the formatter was working without error...

But I am still unable to get code completion, etc.

Am I missing some other settings?

[mhanberg]

You have to enable completions in the settings.

Could you provide a repro project with the dev container config, etc ?