feat(submodules): add test for submodule passthru

tests/default.nix

@@ -37,6 +37,7 @@ let
           ./submodules/defaults.nix
           ./submodules/versioning.nix
           ./submodules/exports.nix
+          ./submodules/passthru.nix
         ];
         testing.args = {
           inherit images k8sVersion;

tests/submodules/passthru.nix

@@ -0,0 +1,59 @@
+{ name, config, lib, kubenix, ... }:
+
+with lib;
+
+let
+  submodule = { name, ... }: {
+    imports = [ kubenix.modules.submodule ];
+
+    config.submodule = {
+      name = "subm";
+      passthru.global.${name} = "true";
+    };
+  };
+in {
+  imports = with kubenix.modules; [ test submodules ];
+
+  options = {
+    global = mkOption {
+      description = "Global value";
+      type = types.attrs;
+      default = {};
+    };
+  };
+
+  config = {
+    test = {
+      name = "submodules-passthru";
+      description = "Submodules passthru test";
+      assertions = [{
+        message = "should passthru values if passthru enabled";
+        assertion = hasAttr "inst1" config.global && config.global.inst1 == "true";
+      } {
+        message = "should not passthru values if passthru not enabled";
+        assertion = !(hasAttr "inst2" config.global);
+      } {
+        message = "should passthru by default";
+        assertion = hasAttr "inst3" config.global && config.global.inst3 == "true";
+      }];
+    };
+
+    submodules.imports = [{
+      modules = [submodule];
+    }];
+
+    submodules.instances.inst1 = {
+      submodule = "subm";
+      passthru.enable = true;
+    };
+
+    submodules.instances.inst2 = {
+      submodule = "subm";
+      passthru.enable = false;
+    };
+
+    submodules.instances.inst3 = {
+      submodule = "subm";
+    };
+  };
+}