nixos/fanout: add test

nixos/tests/all-tests.nix

@@ -272,6 +272,7 @@ in {
   fail2ban = handleTest ./fail2ban.nix { };
   fakeroute = handleTest ./fakeroute.nix {};
   fancontrol = handleTest ./fancontrol.nix {};
+  fanout = handleTest ./fanout.nix {};
   fcitx5 = handleTest ./fcitx5 {};
   fenics = handleTest ./fenics.nix {};
   ferm = handleTest ./ferm.nix {};

nixos/tests/fanout.nix

@@ -0,0 +1,30 @@
+{ system ? builtins.currentSystem
+, config ? {}
+, pkgs ? import ../.. { inherit system config; }
+}:
+import ./make-test-python.nix ({lib, pkgs, ...}: {
+  name = "fanout";
+  meta.maintainers = [ lib.maintainers.therishidesai ];
+
+  nodes = let
+    cfg = { ... }: {
+      services.fanout = {
+        enable = true;
+        fanoutDevices = 2;
+        bufferSize = 8192;
+      };
+    };
+  in {
+    machine = cfg;
+  };
+
+  testScript = ''
+    start_all()
+
+    # mDNS.
+    machine.wait_for_unit("multi-user.target")
+
+    machine.succeed("test -c /dev/fanout0")
+    machine.succeed("test -c /dev/fanout1")
+  '';
+})