All templates must pass `nix flake check` after clone.

[vic]

This example fails nix flake check with

den/templates/default on  main
❯ nix flake check
warning: unknown flake output 'modules'
evaluation warning: system.stateVersion is not set, defaulting to 26.05. Read why this matters on https://nixos.org/manual/nixos/stable/options.html#opt-system.stateVersion.
error:
       … while checking flake output 'nixosConfigurations'

       … while checking the NixOS configuration 'nixosConfigurations.igloo'

       … while calling the 'head' builtin
         at /nix/store/wzcf74b2g5c3qfg4rcswcz28ngiwzzp0-source/lib/attrsets.nix:1713:13:
         1712|           if length values == 1 || pred here (elemAt values 1) (head values) then
         1713|             head values
             |             ^
         1714|           else

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/wzcf74b2g5c3qfg4rcswcz28ngiwzzp0-source/nixos/modules/system/activation/top-level.nix':

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error:
       Failed assertions:
       - The ‘fileSystems’ option does not specify your root file system.
       - You must set the option ‘boot.loader.grub.devices’ or 'boot.loader.grub.mirroredBoots' to make the system bootable.

den/templates/default on  main

Originally posted by @Buttars in #142 (comment)

[Buttars]

I'll take this on and get a PR open within the next couple of days.

[sjdevries]

This is probably related to this issue.

When I run:

nix flake init -t github:vic/den#example
nix flake update den
nix flake check

The result I get is:

nix flake check
warning: unknown flake output 'modules'
warning: unknown flake output 'denful'
error: Cannot build '/nix/store/a4ifygzyp9z29ghx7zzxx51kp6d8bz7r-check-flake-file.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/vjpl42dfvylmp3mssr2m1i934rzc5kjg-check-flake-file
       Last 11 log lines:
       > --- /nix/store/1nf49d5vbawc25fv7kimw70h9h8whjri-source/flake.nix       1970-01-01 00:00:01.000000000 +0000
       > +++ /nix/store/0d3gkl23ya03v90j5kvy4xzk1jkacykh-flake-formatted     1970-01-01 00:00:01.000000000 +0000
       > @@ -21,7 +21,7 @@
       >        url = "github:nix-community/home-manager";
       >      };
       >      import-tree.url = "github:vic/import-tree";
       > -    nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
       > +    nixpkgs.url = "https://channels.nixos.org/nixpkgs-unstable/nixexprs.tar.xz";
       >      nixpkgs-lib.follows = "nixpkgs";
       >      systems.url = "github:nix-systems/default";
       >    };
       For full logs, run:
         nix log /nix/store/a4ifygzyp9z29ghx7zzxx51kp6d8bz7r-check-flake-file.drv

Though when I continue following the readme.md and run "nix run .#vm" the vm is generated and runs.

[vic]

This is probably related to this issue.

yep, that error is from flake-file, that is checking that the flake.nix is updated with the inputs definitions from modules. turns out that template needs to run .#write-flake so its flake.nix is updated from what source modules say. please send PR fixing this.

[Buttars]

@vic this has been marked as closed. Is this accurate? I only saw lockfile updates in the referenced PR.

[vic]

Well, yes, I tested it locally. The issue before was that we had some boot.loader.enable in templates being enabled ONLY on CI. I removed that condition, and made all template have the bootloader disabled :( and added a USER TODO on each of them asking people to remove that. If you have a better solution, pelase please please do send a PR.