1 files changed, 120 insertions, 0 deletions
diff --git a/nixpkgs/nixos/tests/nixos-rebuild-specialisations.nix b/nixpkgs/nixos/tests/nixos-rebuild-specialisations.nix
new file mode 100644
index 000000000000..9192b8a8a030
--- /dev/null
+++ b/nixpkgs/nixos/tests/nixos-rebuild-specialisations.nix
@@ -0,0 +1,120 @@
+import ./make-test-python.nix ({ pkgs, ... }: {
+  name = "nixos-rebuild-specialisations";
+
+  nodes = {
+    machine = { lib, pkgs, ... }: {
+      imports = [
+        ../modules/profiles/installation-device.nix
+        ../modules/profiles/base.nix
+      ];
+
+      nix.settings = {
+        substituters = lib.mkForce [ ];
+        hashed-mirrors = null;
+        connect-timeout = 1;
+      };
+
+      system.includeBuildDependencies = true;
+
+      system.extraDependencies = [
+        # Not part of the initial build apparently?
+        pkgs.grub2
+      ];
+
+      virtualisation = {
+        cores = 2;
+        memorySize = 4096;
+      };
+    };
+  };
+
+  testScript =
+    let
+      configFile = pkgs.writeText "configuration.nix" ''
+        { lib, pkgs, ... }: {
+          imports = [
+            ./hardware-configuration.nix
+            <nixpkgs/nixos/modules/testing/test-instrumentation.nix>
+          ];
+
+          boot.loader.grub = {
+            enable = true;
+            device = "/dev/vda";
+            forceInstall = true;
+          };
+
+          documentation.enable = false;
+
+          environment.systemPackages = [
+            (pkgs.writeShellScriptBin "parent" "")
+          ];
+
+          specialisation.foo = {
+            inheritParentConfig = true;
+
+            configuration = { ... }: {
+              environment.systemPackages = [
+                (pkgs.writeShellScriptBin "foo" "")
+              ];
+            };
+          };
+
+          specialisation.bar = {
+            inheritParentConfig = true;
+
+            configuration = { ... }: {
+              environment.systemPackages = [
+                (pkgs.writeShellScriptBin "bar" "")
+              ];
+            };
+          };
+        }
+      '';
+
+    in
+    ''
+      machine.start()
+      machine.succeed("udevadm settle")
+      machine.wait_for_unit("multi-user.target")
+
+      machine.succeed("nixos-generate-config")
+      machine.copy_from_host(
+          "${configFile}",
+          "/etc/nixos/configuration.nix",
+      )
+
+      with subtest("Switch to the base system"):
+          machine.succeed("nixos-rebuild switch")
+          machine.succeed("parent")
+          machine.fail("foo")
+          machine.fail("bar")
+
+      with subtest("Switch from base system into a specialization"):
+          machine.succeed("nixos-rebuild switch --specialisation foo")
+          machine.succeed("parent")
+          machine.succeed("foo")
+          machine.fail("bar")
+
+      with subtest("Switch from specialization into another specialization"):
+          machine.succeed("nixos-rebuild switch -c bar")
+          machine.succeed("parent")
+          machine.fail("foo")
+          machine.succeed("bar")
+
+      with subtest("Switch from specialization into the base system"):
+          machine.succeed("nixos-rebuild switch")
+          machine.succeed("parent")
+          machine.fail("foo")
+          machine.fail("bar")
+
+      with subtest("Switch into specialization using `nixos-rebuild test`"):
+          machine.succeed("nixos-rebuild test --specialisation foo")
+          machine.succeed("parent")
+          machine.succeed("foo")
+          machine.fail("bar")
+
+      with subtest("Make sure nonsense command combinations are forbidden"):
+          machine.fail("nixos-rebuild boot --specialisation foo")
+          machine.fail("nixos-rebuild boot -c foo")
+    '';
+})