Add a test for the location submodule: Addressing.

modules/metanix-core.nix

@@ -31,6 +31,12 @@ in
       description = "System definitions from meta.nix.";
     };
 
+    policy = mkOption {
+      type = types.attrs;
+      readOnly = true;
+      description = "Policy subtree from meta.nix.";
+    };
+
     # Computed addressing
     network = mkOption {
       type = types.attrs;

tests/addressing-smoke.nix

@@ -0,0 +1,36 @@
+let
+  lib = import <nixpkgs/lib> { };
+  addressing = import ./lib/addressing { inherit lib; };
+
+  spec = {
+    domain = "kasear.net";
+
+    locations = {
+      home = {
+        # note: owner/admins/users are *ignored* by mkNetworkFromSpec
+        owner = "yaro";
+        admins = [ "ops" ];
+
+        main = {
+          vlan = 10;
+          hosts = {
+            deimos = {
+              role = "server";
+              hostId = 1;
+            };
+
+            router = {
+              role = "router";
+              hostId = 1;
+            };
+          };
+        };
+      };
+    };
+  };
+
+  network = addressing.mkNetworkFromSpec spec;
+in
+{
+  inherit spec network;
+}