nixd (or nix) may request the inputs in some edge cases

[hellodword]

The version I'm using is https://github.com/NixOS/nixpkgs/blob/06570e54184cb7f3aecb16c7c5ef82a871ce5873/pkgs/development/tools/language-servers/nixd/default.nix

Reproduce:

1. prepare a local git+ssh server with docker

FROM ubuntu:latest

RUN apt-get update && \
    apt-get install git openssh-server -y && \
    git clone --bare https://codeberg.org/mhwombat/hello-flake.git && \
    passwd -d root && \
    printf '\nPasswordAuthentication yes\nPermitEmptyPasswords yes\nPermitRootLogin yes\n' | tee -a /etc/ssh/sshd_config && \
    service ssh start

EXPOSE 22

CMD ["/usr/sbin/sshd","-D"]

2. run the git+ssh server and trust it

docker build -t nixd-issue .
docker run --rm -p 127.0.0.1:22222:22 nixd-issue
# trust
ssh root@127.0.0.1 -p 22222 uname

3. commit the flake

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";

    flake-compat = {
      url = "github:inclyc/flake-compat/70e56389c58bbd300d11778913b255477ebbae22";
      flake = false;
    };

    disko = {
      url = "github:nix-community/disko/f0b9f374bb42fdcd57baa7d4448ac5d4788226bd";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    privates.url = "git+ssh://root@127.0.0.1:22222/hello-flake.git";
  };

  outputs = { self, nixpkgs, ... }@ inputs:
    let
      system = "x86_64-linux";

      minimal = {
        users.users = {
          admin = {
            isNormalUser = true;
            extraGroups = [ "wheel" ];
            password = "admin";
          };
        };

        virtualisation.vmVariant = {
          virtualisation = {
            memorySize = 1024;
            cores = 2;
            graphics = false;
          };
        };

        system.stateVersion = "23.05";
      };
    in
    {
      nixosConfigurations = {

        test-vm-nixd-issue = nixpkgs.lib.nixosSystem {
          inherit system;
          specialArgs = { inherit inputs; };
          modules = [
            (
              { config, lib, pkgs, inputs, ... }: (minimal // {

                boot.kernelPackages = pkgs.linuxPackages_latest;

                imports = [
                  inputs.disko.nixosModules.disko
                ];

                disko = {
                  enableConfig = false;
                  devices.disk = {
                    "${inputs.privates.apps.x86_64-linux.default.type}" = { };
                  };
                };

              })
            )
          ];
        };

      };
    };
}

nix flake update
# git add ...
# git commit ...

4. lsp config

{
    "nix.enableLanguageServer": true,
    "nix.serverPath": "nixd",
    "nix.serverSettings": {
        "nixd": {
            "eval": {
                "target": {
                    "args": [
                        "-f",
                        "default.nix"
                    ],
                    "installable": "nixosConfigurations.test-vm-nixd-issue.config"
                },
                "workers": 5
            },
            "formatting": {
                "command": "nixpkgs-fmt"
            },
            "options": {
                "enable": true,
                "target": {
                    "args": [],
                    "installable": ".#nixosConfigurations.test-vm-nixd-issue.options"
                }
            }
        }
    }
}

5. close all and reboot
6. listen the 22222 port

nix-shell -p nmap --run 'ncat -v -k -l 22222'

7. open the editor, you will catch the request

Ncat: Connection from 127.0.0.1:53768.
SSH-2.0-OpenSSH_9.6

[hellodword]

With latest nixd-next: https://github.com/nix-community/nixd/tree/e7e26a16adb83d6c1b7a74615b6c77fe4c51bc82

[inclyc]

With latest nixd-next: https://github.com/nix-community/nixd/tree/e7e26a16adb83d6c1b7a74615b6c77fe4c51bc82

This is not complete and your version may not even deal with lambdas. That's why you see these meaningless errors.

nixd-next is on a very early stage: #283