nixos/tests/networking: Add a test for loopback

It serves as a regression test, because right now if you enable
networking.useNetworkd the default loopback interface doesn't get
assigned any IP addresses.

To be sure, I have bisected this and it has been introduced with the
update to systemd 228 in 1da87d4.

Only the "scripted" networking tests have to succeed in order to trigger
a channel update of nixos-unstable, so I'm leaving this test as broken
and we have to figure out next what's the *exact* reason for the
breakage.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/nixos/tests/networking.nix b/nixos/tests/networking.nix
index 6a7f63702c41..813d7c2bf516 100644
--- a/nixos/tests/networking.nix
+++ b/nixos/tests/networking.nix
@@ -31,6 +31,17 @@ import ./make-test.nix ({ pkgs, networkd, test, ... }:
         };
       };
     testCases = {
+      loopback = {
+        name = "Loopback";
+        machine.networking.useNetworkd = networkd;
+        testScript = ''
+          startAll;
+          $machine->waitForUnit("network-interfaces.target");
+          $machine->waitForUnit("network.target");
+          $machine->succeed("ip addr show lo | grep -q 'inet 127.0.0.1/8 '");
+          $machine->succeed("ip addr show lo | grep -q 'inet6 ::1/128 '");
+        '';
+      };
       static = {
         name = "Static";
         nodes.router = router;