nixos/timezone: Fix evaluation error

aszlig · aszlig · commit 4f901203e8d1 · 2017-07-31T17:15:30.000+02:00
Evaluation error introduced in a0d4640. If the value for timeZone is null it shouldn't be even tried to coerce it into a string. Signed-off-by: aszlig <aszlig@redmoonstudios.org> Cc: @lheckemann, @joachifm
diff --git a/nixos/modules/config/timezone.nix b/nixos/modules/config/timezone.nix
@@ -47,7 +47,7 @@ in
 
     environment.etc = {
       zoneinfo.source = tzdir;
-    } // lib.optionalAttrs (config.time.timeZone == null) {
+    } // lib.optionalAttrs (config.time.timeZone != null) {
         localtime.source = "/etc/zoneinfo/${config.time.timeZone}";
         localtime.mode = "direct-symlink";
       };
