nixpkgs-disabled: add module

This commit introduces the `nixpkgs-disabled` module, that is
basically a mock of `nixpkgs` module where any value different from
`null` will cause an assertion error.

This is to help debugging cases where `home-manager.useGlobalPkgs` is
set to `true` and `nixpkgs.*` options are being used.

Nowadays this returns the following error:

```
error: The option `home-manager.users.<user>.nixpkgs` does not exist.
```

This will change too:

```
error: `nixpkgs` options are disabled when `home-manager.useGlobalPkgs` is enabled.
```

That will direct the user to the correct solution (either removing
`nixpkgs` or disable `home-manager.useGlobalPkgs`).
This commit is contained in:
Thiago Kenji Okada 2021-10-13 13:42:12 -03:00 committed by Robert Helgesson
parent b88c863b40
commit 223a4a17a4
No known key found for this signature in database
GPG key ID: 36BDAA14C2797E89
3 changed files with 77 additions and 1 deletions

2
.github/CODEOWNERS vendored
View file

@ -19,6 +19,8 @@
/modules/misc/news.nix @rycee
/modules/misc/nixpkgs-disabled.nix @thiagokokada
/modules/misc/numlock.nix @evanjs
/tests/modules/misc/numlock @evanjs

View file

@ -0,0 +1,73 @@
{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.nixpkgs;
# Copied from nixpkgs.nix.
isConfig = x: builtins.isAttrs x || builtins.isFunction x;
# Copied from nixpkgs.nix.
optCall = f: x: if builtins.isFunction f then f x else f;
# Copied from nixpkgs.nix.
mergeConfig = lhs_: rhs_:
let
lhs = optCall lhs_ { inherit pkgs; };
rhs = optCall rhs_ { inherit pkgs; };
in lhs // rhs // optionalAttrs (lhs ? packageOverrides) {
packageOverrides = pkgs:
optCall lhs.packageOverrides pkgs
// optCall (attrByPath [ "packageOverrides" ] ({ }) rhs) pkgs;
} // optionalAttrs (lhs ? perlPackageOverrides) {
perlPackageOverrides = pkgs:
optCall lhs.perlPackageOverrides pkgs
// optCall (attrByPath [ "perlPackageOverrides" ] ({ }) rhs) pkgs;
};
# Copied from nixpkgs.nix.
configType = mkOptionType {
name = "nixpkgs-config";
description = "nixpkgs config";
check = x:
let traceXIfNot = c: if c x then true else lib.traceSeqN 1 x false;
in traceXIfNot isConfig;
merge = args: fold (def: mergeConfig def.value) { };
};
# Copied from nixpkgs.nix.
overlayType = mkOptionType {
name = "nixpkgs-overlay";
description = "nixpkgs overlay";
check = builtins.isFunction;
merge = lib.mergeOneOption;
};
in {
meta.maintainers = with maintainers; [ thiagokokada ];
options.nixpkgs = {
config = mkOption {
default = null;
type = types.nullOr configType;
visible = false;
};
overlays = mkOption {
default = null;
type = types.nullOr (types.listOf overlayType);
visible = false;
};
};
config = {
assertions = [{
assertion = cfg.config == null || cfg.overlays == null;
message = ''
`nixpkgs` options are disabled when `home-manager.useGlobalPkgs` is enabled.
'';
}];
};
}

View file

@ -242,7 +242,8 @@ let
./xsession.nix
(pkgs.path + "/nixos/modules/misc/assertions.nix")
(pkgs.path + "/nixos/modules/misc/meta.nix")
] ++ optional useNixpkgsModule ./misc/nixpkgs.nix;
] ++ optional useNixpkgsModule ./misc/nixpkgs.nix
++ optional (!useNixpkgsModule) ./misc/nixpkgs-disabled.nix;
pkgsModule = { config, ... }: {
config = {