nixos,nixpkgs: Add module classes

This allows modules that declare their class to be checked.
While that's not most user modules, frameworks can take advantage
of this by setting declaring the module class for their users.
That way, the mistake of importing a module into the wrong hierarchy
can be reported more clearly in some cases.

3 files changed, 8 insertions, 2 deletions

diff --git a/nixos/lib/eval-cacheable-options.nix b/nixos/lib/eval-cacheable-options.nix
index c3ba2ce66375..d26967ebe09b 100644
--- a/nixos/lib/eval-cacheable-options.nix
+++ b/nixos/lib/eval-cacheable-options.nix
@@ -33,6 +33,7 @@ let
     ];
     specialArgs = {
       inherit config pkgs utils;
+      class = "nixos";
     };
   };
   docs = import "${nixosPath}/doc/manual" {
diff --git a/nixos/lib/eval-config-minimal.nix b/nixos/lib/eval-config-minimal.nix
index d45b9ffd4261..7e28f4305127 100644
--- a/nixos/lib/eval-config-minimal.nix
+++ b/nixos/lib/eval-config-minimal.nix
@@ -40,7 +40,9 @@ let
     inherit prefix modules;
     specialArgs = {
       modulesPath = builtins.toString ../modules;
-    } // specialArgs;
+    } // specialArgs // {
+      class = "nixos";
+    };
   };
 
 in
diff --git a/nixos/lib/testing/default.nix b/nixos/lib/testing/default.nix
index 9d4f9dbc43d7..1bd6278ce684 100644
--- a/nixos/lib/testing/default.nix
+++ b/nixos/lib/testing/default.nix
@@ -1,7 +1,10 @@
 { lib }:
 let
 
-  evalTest = module: lib.evalModules { modules = testModules ++ [ module ]; };
+  evalTest = module: lib.evalModules {
+    modules = testModules ++ [ module ];
+    specialArgs.class = "nixosTest";
+  };
   runTest = module: (evalTest ({ config, ... }: { imports = [ module ]; result = config.test; })).config.result;
 
   testModules = [