fix include-less parametric in provides

nix/lib.nix

@@ -13,7 +13,9 @@ let
     aspect
     // {
       __functor = self: ctx: {
-        includes = builtins.filter (x: x != { }) (map (apply ctx) (builtins.filter isFn self.includes));
+        includes = builtins.filter (x: x != { }) (
+          map (apply ctx) (builtins.filter isFn (self.includes or [ ]))
+        );
       };
     };
 
@@ -35,7 +37,7 @@ let
         self:
         { class, aspect-chain }:
         {
-          includes = map (applyStatics { inherit class aspect-chain; }) self.includes;
+          includes = map (applyStatics { inherit class aspect-chain; }) (self.includes or [ ]);
         };
     };
 

templates/ci/modules/features/provides-parametric.nix

@@ -0,0 +1,45 @@
+{ denTest, inputs, ... }:
+{
+
+  flake.tests.provides-parametric = {
+
+    test-parametric-inside-provides = denTest (
+      {
+        den,
+        ns,
+        igloo,
+        ...
+      }:
+      {
+        den.hosts.x86_64-linux.igloo.users.tux = { };
+
+        imports = [ (inputs.den.namespace "ns" false) ];
+
+        ns.foo = den.lib.parametric { };
+        ns.bar.provides.baz = den.lib.parametric { };
+        ns.a = den.lib.parametric {
+          provides.b = den.lib.parametric { };
+          provides.c = den.lib.parametric { };
+          provides.d = den.lib.parametric {
+            provides.e = den.lib.parametric { nixos.networking.hostName = "pinguino"; };
+          };
+        };
+
+        den.aspects.igloo.includes = [
+          ns.foo
+          ns.bar._.baz
+          ns.a
+          ns.a._.b
+          ns.a._.c
+          ns.a._.d
+          ns.a._.d._.e
+        ];
+
+        expr = igloo.networking.hostName;
+        expected = "pinguino";
+      }
+    );
+
+  };
+
+}