"Improved attribute path validation" on NixOS-WSL breaks building home-manager configuration

[girlpunk]

I have confirmed that this is a bug related to nh

• This is a bug, and not an user error or a support request. I understand that my issue will be closed if it is not a bug in NH.
• I have checked the issues tab and confirmed that my issue has not yet been reported. I understand that my issue will be closed if it is a duplicate.

Description

Since upgrading to v4.3.0 I have been unable to switch home-manager configurations, I believe this is due to the "improved attribute path validation" added in 542479a.

# nh home switch /mnt/d/nix#homeConfigurations.me@work.activationPackage
Error:
   0: Attribute path is too specific: homeConfigurations.me@work.activationPackage. Home Manager only allows configuration names. Please either:
        1. Use the flake reference without attributes (e.g., '.')
        2. Specify only the configuration name (e.g., '.#me@work')

Location:
   src/home.rs:271

Using only the configuration name as suggested by the error message also generates an error:

#nh home switch /mnt/d/nix#"me@work"
> Building Home-Manager configuration
warning: Git tree '/mnt/d/nix' is dirty
error: flake 'git+file:///mnt/d/nix' does not provide attribute 'packages.x86_64-linux.me@work', 'legacyPackages.x86_64-linux.me@work' or 'me@work'
┏━ 1 Errors:
┃ error: flake 'git+file:///mnt/d/nix' does not provide attribute 'packages.x86_64-linux.me@work', 'legacyPackages.x86_64-linux.me@work' or 'me@work'
┣━━━
┗━ ∑ ⚠ Exited with 1 errors reported by nix at 10:54:12 after 0s
Error:
   0: Failed to build Home-Manager configuration
   1: Command exited with status Exited(1)

Location:
   src/commands.rs:880

And trying the configuration name within the homeConfigurations object gives a third, different error:

nh home switch /mnt/d/nix#"me@work"
> Building Home-Manager configuration
warning: Git tree '/mnt/d/nix' is dirty
error: flake 'git+file:///mnt/d/nix' does not provide attribute 'packages.x86_64-linux.me@work', 'legacyPackages.x86_64-linux.me@work' or 'me@work'
┏━ 1 Errors:
┃ error: flake 'git+file:///mnt/d/nix' does not provide attribute 'packages.x86_64-linux.me@work', 'legacyPackages.x86_64-linux.me@work' or 'me@work'
┣━━━
┗━ ∑ ⚠ Exited with 1 errors reported by nix at 10:54:12 after 0s
Error:
   0: Failed to build Home-Manager configuration
   1: Command exited with status Exited(1)

Location:
   src/commands.rs:880

Installation Method

Stable Release (nixpkgs, pkgs.nh from nixos-unstable or nixos-yy-mm)

Installation Method (Other)

No response

NH Version

nh 4.3.0

System Information

• system: "x86_64-linux"
• host os: Linux 5.15.167.4-microsoft-standard-WSL2, NixOS, 25.11 (Xantusia), 25.11.20260324.1073dad
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.33.3
• channels(root): "nixos-25.05, nixos-wsl-25.05.tar.gz"
• nixpkgs: /nix/store/i2mnjncmkjkl0gd7jhvv6vlakvr9p9pm-source