Commit 5f197bf5 authored by Robert Hensing's avatar Robert Hensing
Browse files

nixos/eval-config: Deprecate NIXOS_EXTRA_MODULE_PATH 

This gets rid of a potentially confusing behavior that doesn't need to
be in NixOS, and nobody ever bothered to add a test for it.
Let's keep things simple!
The suggested snippet is better than this feature ever was, and will be
in the user's face, where it belongs, kindly.

Tested with

    nix-instantiate nixos/lib/eval-config.nix --arg modules '[{fileSystems."/".device="x";boot.loader.grub.enable=false;}]' -A config.system.build.toplevel
    NIXOS_EXTRA_MODULE_PATH=$HOME/whatever.nix nix-instantiate nixos/lib/eval-config.nix --arg modules '[{fileSystems."/".device="x";boot.loader.grub.enable=false;}]' -A config.system.build.toplevel
parent 4ba22a88

nixos/doc/manual/development/importing-modules.section.md

+0 −28
Original line number Diff line number Diff line
@@ -16,31 +16,3 @@ outside of Nixpkgs. These modules can be imported: 
  services.exampleModule.enable = true;

}

```
 


The environment variable `NIXOS_EXTRA_MODULE_PATH` is an absolute path

to a NixOS module that is included alongside the Nixpkgs NixOS modules.

Like any NixOS module, this module can import additional modules:



```nix

# ./module-list/default.nix

[

  ./example-module1

  ./example-module2

]

```



```nix

# ./extra-module/default.nix

{ imports = import ./module-list.nix; }

```



```nix

# NIXOS_EXTRA_MODULE_PATH=/absolute/path/to/extra-module

{ config, lib, pkgs, ... }:



{

  # No `imports` needed



  services.exampleModule1.enable = true;

}

```

nixos/doc/manual/development/meta-attributes.section.md

+1 −1
Original line number Diff line number Diff line
@@ -45,7 +45,7 @@ file. 
-  `buildDocsInSandbox` indicates whether the option documentation for the

   module can be built in a derivation sandbox. This option is currently only

   honored for modules shipped by nixpkgs. User modules and modules taken from

   `NIXOS_EXTRA_MODULE_PATH` are always built outside of the sandbox, as has

   `extraModules` are always built outside of the sandbox, as has

   been the case in previous releases.



   Building NixOS option documentation in a sandbox allows caching of the built

nixos/lib/eval-config.nix

+23 −2
Original line number Diff line number Diff line
@@ -30,8 +30,29 @@ evalConfigArgs@ 
  check ? true

, prefix ? []

, lib ? import ../../lib

, extraModules ? let e = builtins.getEnv "NIXOS_EXTRA_MODULE_PATH";

                 in lib.optional (e != "") (import e)

, extraModules ?

    let e = builtins.getEnv "NIXOS_EXTRA_MODULE_PATH";

    in lib.optional (e != "") (

      lib.warn

        ''

          The NIXOS_EXTRA_MODULE_PATH environment variable is deprecated and will be

          removed in NixOS 25.05.

          We recommend a workflow where you update the expression files instead, but

          if you wish to continue to use this variable, you may do so with a module like:



          {

            imports = [

              (builtins.getEnv "NIXOS_EXTRA_MODULE_PATH")

            ];

          }



          This has the benefit that your configuration hints at the

          non-standard workflow.

        ''

        # NOTE: this import call is unnecessary and it even removes the file name

        #       from error messages.

        import e

    )

}:



let