nixos/systemd: merge unit options as lists when at least one value is a list

2 files changed, 42 insertions, 0 deletions

diff --git a/pkgs/test/systemd/default.nix b/pkgs/test/systemd/default.nix
new file mode 100644
index 0000000000000..2208bf794481f
--- /dev/null
+++ b/pkgs/test/systemd/default.nix
@@ -0,0 +1,5 @@
+{ lib, callPackage }:
+
+lib.recurseIntoAttrs {
+  nixos = callPackage ./nixos { };
+}
diff --git a/pkgs/test/systemd/nixos/default.nix b/pkgs/test/systemd/nixos/default.nix
new file mode 100644
index 0000000000000..e45399b635167
--- /dev/null
+++ b/pkgs/test/systemd/nixos/default.nix
@@ -0,0 +1,37 @@
+{ pkgs, lib, stdenv, ... }:
+
+lib.runTests {
+  # Merging two non-list definitions must still result in an error
+  # about a conflicting definition.
+  test-unitOption-merging-non-lists-conflict =
+    let nixos = pkgs.nixos {
+        system.stateVersion = lib.trivial.release;
+        systemd.services.systemd-test-nixos = {
+          serviceConfig = lib.mkMerge [
+            { StateDirectory = "foo"; }
+            { StateDirectory = "bar"; }
+          ];
+        };
+      };
+    in {
+    expr = (builtins.tryEval (nixos.config.systemd.services.systemd-test-nixos.serviceConfig.StateDirectory)).success;
+    expected = false;
+  };
+
+  # Merging must lift non-list definitions to a list
+  # if at least one of them is a list.
+  test-unitOption-merging-list-non-list-append =
+    let nixos = pkgs.nixos {
+        system.stateVersion = lib.trivial.release;
+        systemd.services.systemd-test-nixos = {
+          serviceConfig = lib.mkMerge [
+            { StateDirectory = "foo"; }
+            { StateDirectory = ["bar"]; }
+          ];
+        };
+      };
+    in {
+    expr = nixos.config.systemd.services.systemd-test-nixos.serviceConfig.StateDirectory;
+    expected = [ "foo" "bar" ];
+  };
+}