Error " 'fromHexString' missing" when configuring touchpad

[MichaelBrunn3r]

Nix fails to evaluate this config ...

programs.plasma.input.touchpads = [
  {
    enable = true;
    name = "PIXA3854:00 093A:0274 Touchpad";
    vendorId = "093a";
    productId = "0274";
    naturalScroll = true;
  }
];

... with the error:

error: attribute 'fromHexString' missing

at /nix/store/fbcw9dxpgfkv7h1pl6bm0llkpvpa1v2z-source/modules/input.nix:158:40:

  157|       touchName = touchpad.name;
  158|       touchVendor = builtins.toString (lib.fromHexString touchpad.vendorId);
     |                                        ^
  159|       touchProduct = builtins.toString (lib.fromHexString touchpad.productId);

As I understand, the code expects lib to contain a fromHexString function, but it is missing. Could this be because of I misconfigured plasma-manager and it gets evaluated with an invalid lib argument?

Is it possible that the code uses lib.trivial.fromHexString from the unstable channel? https://nixos.org/manual/nixpkgs/unstable/#function-library-lib.trivial.fromHexString

That would make sense, because the flake configuration example uses the unstable channel. Is there a way to configure plasma-manager to use the unstable channel without having it as a default for all my packages?

Something like this does not seem to work :/

inputs = {
  nixpkgs.url = "github:nixos/nixpkgs/nixos-24.05";
  nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";
  home-manager = {
    url = github:nix-community/home-manager/release-24.05;
    inputs.nixpkgs.follows = "nixpkgs-unstable";
  };
  plasma-manager = {
    url = "github:nix-community/plasma-manager";
    inputs.nixpkgs.follows = "nixpkgs-unstable";
    inputs.home-manager.follows = "home-manager";
  };
};

[HeitorAugustoLN]

What is your current nixpkgs-unstable commit?

[HeitorAugustoLN]

This function was added like 2 months ago, so maybe running:

nix flake lock --update-input nixpkgs-unstable could fix it

[MichaelBrunn3r]

My unstable channel was not up to date, now it is at cb9a96f23c491c081b38eab96d22fa958043c9fa, 3 (?) days old. Didn't fix the issue unfortunately

[MichaelBrunn3r]

That's strange, it looks like plasma-manager gets the correct nixpkgs input in the repl:

> :lf .

> inputs.plasma-manager.inputs.nixpkgs.rev
"cb9a96f23c491c081b38eab96d22fa958043c9fa" # This is the 3 day old unstable commit

> inputs.plasma-manager.inputs.nixpkgs.lib.trivial.fromHexString
«lambda @ /nix/store/4cpakzyvfw1rmm9v5i3387x6jd2h1v86-source/lib/trivial.nix:1098:19»

Could the problem be that the code calls lib.fromHexString instead of lib.trivial.fromHexString?

Edit: No, lib.fromHexString exists as well

> inputs.plasma-manager.inputs.nixpkgs.lib.fromHexString
«lambda @ /nix/store/4cpakzyvfw1rmm9v5i3387x6jd2h1v86-source/lib/trivial.nix:1098:19»

[MichaelBrunn3r]

Hm, home-manager does not seem to use the correct version:

home-manager.users.michael = {lib, ...}: {
  some.random.option = lib.version;
}

repl> nixosConfigurations.<conf>.config.home-manager.users.michael.some.random.option = "24.05.20240805.883180e"

If it was using the unstable nixpkgs, it would be "24.11.20240804.cb9a96f".

That means I configured home-manager incorrectly, I guess.

I configured my home-manager to use the unstable nixpkgs:

inputs = {
  nixpkgs.url = "github:nixos/nixpkgs/nixos-24.05";
  nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";
  home-manager = {
    url = github:nix-community/home-manager;
    inputs.nixpkgs.follows = "nixpkgs-unstable";
  };
  plasma-manager = {
    url = "github:nix-community/plasma-manager";
    inputs.nixpkgs.follows = "nixpkgs-unstable";
    inputs.home-manager.follows = "home-manager";
  };
};

And I include its module like this:

outputs = inputs @ {
  self,
  nixpkgs,
  nixpkgs-unstable,
  home-manager,
  plasma-manager,
  ...
}:  {
  nixosConfigurations.<conf> = nixpkgs.lib.nixosSystem {
    system = "x86_64-linux";
    modules =
      [
        home-manager.nixosModules.home-manager
        {
          home-manager.sharedModules = [
            plasma-manager.homeManagerModules.plasma-manager
          ];
        }
      ];
  };
};

I set my stateVersion to 24.11:

config = {
  home-manager = {
    useUserPackages = true;
    useGlobalPkgs = true;

    users.michael = {...}: {
      home.stateVersion = "24.11";
    };
  };
};

[HeitorAugustoLN]

I think you might need to add an unstable home manager input, so you can make plasma manager follow it?

[MichaelBrunn3r]

Completely switching to unstable works, but I want to use the stable channel:

inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    home-manager = {
      url = github:nix-community/home-manager;
      inputs.nixpkgs.follows = "nixpkgs";
    };
    plasma-manager = {
      url = "github:nix-community/plasma-manager";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.home-manager.follows = "home-manager";
    };
};

And regarding your idea, I thought my home-manager was already unstable

home-manager = {
  url = github:nix-community/home-manager; # i.e. straight from master instead of  .../release-24.05
  inputs.nixpkgs.follows = "nixpkgs";
};

Or do you mean I have to have both a stable and unstable home-manager?

[HeitorAugustoLN]

I meant that you should have both, one for normal usage, and unstable for plasma-manager

[MichaelBrunn3r]

Like this?

inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-24.05";
    nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";
    home-manager = {
      url = github:nix-community/home-manager/release-24.05;
      inputs.nixpkgs.follows = "nixpkgs";
    };
    home-manager-unstable = {
      url = github:nix-community/home-manager;
      inputs.nixpkgs.follows = "nixpkgs-unstable";
    };
    plasma-manager = {
      url = "github:nix-community/plasma-manager";
      inputs.nixpkgs.follows = "nixpkgs-unstable";
      inputs.home-manager.follows = "home-manager-unstable";
    };
  };

Didn't work.

I think I will spin up a VM and start a config from scratch, maybe my flake is just unpredictable.

[HeitorAugustoLN]

Yes, i thought it would work

[HeitorAugustoLN]

I think that for it to work, the configuration needs to be in the used with the unstable version of the home manager module

[HeitorAugustoLN]

I think the possible solution here would be using a standalone home manager configuration for plasma manager with the unstable home manager input

[MichaelBrunn3r]

How would I configure this? I don't understand how that's different from what I did.
But I think I spent to much time on this already anywaus. It sounds like I would to change my flake config (a lot?) just to fix this version incompatibility. I think I'm fine with just waiting for the 24.11 release.

In the meantime doing it via the configFile option does what I want:

home-manager.users.michael = {
  programs.plasma = {
          configFile.kcminputrc."Libinput/2362/628/PIXA3854:00 093A:0274 Touchpad"."NaturalScroll" = true;
  };
};

[HeitorAugustoLN]

It is better to manually configure this, doing this workaround would be really hacky

[HeitorAugustoLN]

@magnouvean maybe we should start doing branches for fixed releases, starting from 24.11 to avoid problems like this?

[magnouvean]

That would be a good solution. Hopefully it wouldn't take too much work though such that we could realistically maintain both branches. We should probaby take inspiration from home-manager for how they do this.

[HeitorAugustoLN]

That would be a good solution. Hopefully it wouldn't take too much work though such that we could realistically maintain both branches. We should probaby take inspiration from home-manager for how they do this.

It would be relatively simple. We can create a github action that automatically backports to the current fixed release based on a label, that is basically what home-manager does (besides using a label), they ensure that the change is backwards compatible, and then if it is, it gets backported, if it is not, it gets only in the master branch