Move the test module into a separate dir.

flake.nix

@@ -195,7 +195,7 @@
       systemConfigs.default = self.lib.makeSystemConfig {
         system = flake-utils.lib.system.x86_64-linux;
         modules = [
-          ./nix/modules
+          ./test/nix/modules
         ];
       };
     };

nix/lib.nix

@@ -30,7 +30,7 @@ in
       config = (lib.evalModules {
         modules = [
           extraArgsModule
-          ./modules/system-manager.nix
+          ./modules
         ] ++ modules;
       }).config;
 

nix/modules/default.nix

@@ -1,80 +1,81 @@
 { lib
-, pkgs
+, config
 , ...
 }:
 {
-  config = {
+  imports = [
-    environment.etc = {
+    ./etc.nix
-      foo = {
+    ./systemd.nix
-        text = ''
+  ];
-          This is just a test!
-        '';
-        target = "foo_test";
-      };
 
-      "foo.conf".text = ''
+  options = {
-        launch_the_rockets = true
+    assertions = lib.mkOption {
+      type = lib.types.listOf lib.types.unspecified;
+      internal = true;
+      default = [ ];
+      example = [{ assertion = false; message = "you can't enable this for that reason"; }];
+      description = lib.mdDoc ''
+        This option allows modules to express conditions that must
+        hold for the evaluation of the system configuration to
+        succeed, along with associated error messages for the user.
       '';
+    };
 
-      "baz/bar/foo2" = {
+    warnings = lib.mkOption {
-        text = ''
+      internal = true;
-          Another test!
+      default = [ ];
-        '';
+      type = lib.types.listOf lib.types.str;
-        mode = "symlink";
+      example = [ "The `foo' service is deprecated and will go away soon!" ];
-      };
+      description = lib.mdDoc ''
+        This option allows modules to show warnings to users during
+        the evaluation of the system configuration.
+      '';
+    };
 
-      foo3 = {
+    system-manager = {
-        text = "boo!";
+      allowAnyDistro = lib.mkEnableOption "the usage of system-manager on untested distributions";
-        mode = "0700";
-        user = "root";
-        group = "root";
-      };
 
-      "a/nested/example/foo3" = {
+      preActivationAssertions = lib.mkOption {
-        text = "boo!";
+        type = with lib.types; attrsOf (submodule ({ name, ... }: {
-        mode = "0764";
+          options = {
-        user = "root";
+            enable = lib.mkEnableOption "the assertion";
-        group = "root";
-      };
 
-      "a/nested/example2/foo3" = {
+            name = lib.mkOption {
-        text = "boo!";
+              type = lib.types.str;
-        mode = "0764";
+              default = name;
-        user = "root";
+            };
-        group = "root";
-      };
 
-      out-of-store = {
+            script = lib.mkOption {
-        source = "/run/systemd/system/";
+              type = lib.types.str;
+            };
+          };
+        }));
+        default = { };
       };
     };
-    systemd.services =
+  };
-      lib.listToAttrs
+
-        (lib.flip lib.genList 10 (ix:
+  config = {
-          lib.nameValuePair "service-${toString ix}"
+
-            {
+    system-manager.preActivationAssertions = {
-              enable = true;
+      osVersion =
-              description = "service-${toString ix}";
+        let
-              wants = [ "network-online.target" ];
+          supportedIds = [ "nixos" "ubuntu" ];
-              after = [
+        in
-                "network-online.target"
+        {
-                "avahi-daemon.service"
+          enable = !config.system-manager.allowAnyDistro;
-                "chrony.service"
+          script = ''
-                "nss-lookup.target"
+            source /etc/os-release
-                "tinc.service"
+            ${lib.concatStringsSep "\n" (lib.flip map supportedIds (supportedId: ''
-                "pulseaudio.service"
+              if [ $ID = "${supportedId}" ]; then
-              ];
+                exit 0
-              serviceConfig = {
+              fi
-                Type = "oneshot";
+            ''))}
-                RemainAfterExit = true;
+            echo "This OS is not currently supported."
-                ExecReload = "${lib.getBin pkgs.coreutils}/bin/true";
+            echo "Supported OSs are: ${lib.concatStringsSep ", " supportedIds}"
-              };
+            exit 1
-              wantedBy = [ "multi-user.target" ];
+          '';
-              requiredBy = lib.mkIf (ix > 5) [ "service-0.service" ];
+        };
-              script = ''
+    };
-                sleep ${if ix > 5 then "2" else "1"}
-              '';
-            })
-        );
   };
 }

nix/modules/system-manager.nix

@@ -1,81 +0,0 @@
-{ lib
-, config
-, ...
-}:
-{
-  imports = [
-    ./etc.nix
-    ./systemd.nix
-  ];
-
-  options = {
-    assertions = lib.mkOption {
-      type = lib.types.listOf lib.types.unspecified;
-      internal = true;
-      default = [ ];
-      example = [{ assertion = false; message = "you can't enable this for that reason"; }];
-      description = lib.mdDoc ''
-        This option allows modules to express conditions that must
-        hold for the evaluation of the system configuration to
-        succeed, along with associated error messages for the user.
-      '';
-    };
-
-    warnings = lib.mkOption {
-      internal = true;
-      default = [ ];
-      type = lib.types.listOf lib.types.str;
-      example = [ "The `foo' service is deprecated and will go away soon!" ];
-      description = lib.mdDoc ''
-        This option allows modules to show warnings to users during
-        the evaluation of the system configuration.
-      '';
-    };
-
-    system-manager = {
-      allowAnyDistro = lib.mkEnableOption "the usage of system-manager on untested distributions";
-
-      preActivationAssertions = lib.mkOption {
-        type = with lib.types; attrsOf (submodule ({ name, ... }: {
-          options = {
-            enable = lib.mkEnableOption "the assertion";
-
-            name = lib.mkOption {
-              type = lib.types.str;
-              default = name;
-            };
-
-            script = lib.mkOption {
-              type = lib.types.str;
-            };
-          };
-        }));
-        default = { };
-      };
-    };
-  };
-
-  config = {
-
-    system-manager.preActivationAssertions = {
-      osVersion =
-        let
-          supportedIds = [ "nixos" "ubuntu" ];
-        in
-        {
-          enable = !config.system-manager.allowAnyDistro;
-          script = ''
-            source /etc/os-release
-            ${lib.concatStringsSep "\n" (lib.flip map supportedIds (supportedId: ''
-              if [ $ID = "${supportedId}" ]; then
-                exit 0
-              fi
-            ''))}
-            echo "This OS is not currently supported."
-            echo "Supported OSs are: ${lib.concatStringsSep ", " supportedIds}"
-            exit 1
-          '';
-        };
-    };
-  };
-}

src/generate.rs

@@ -95,6 +95,8 @@ fn find_flake_attr(flake_uri: &str) -> Result<Cow<'_, str>> {
     anyhow::bail!("No suitable flake attribute found, giving up.");
 }
 
+// TODO handle errors better.
+// E.g. when we refer to an unexisting module in the systemConfig definition.
 fn try_flake_attr(flake_uri: &str) -> Result<bool> {
     log::info!("Trying flake URI: {flake_uri}...");
     let status = try_nix_eval(flake_uri)?;

test/nix/modules/default.nix

@@ -0,0 +1,80 @@
+{ lib
+, pkgs
+, ...
+}:
+{
+  config = {
+    environment.etc = {
+      foo = {
+        text = ''
+          This is just a test!
+        '';
+        target = "foo_test";
+      };
+
+      "foo.conf".text = ''
+        launch_the_rockets = true
+      '';
+
+      "baz/bar/foo2" = {
+        text = ''
+          Another test!
+        '';
+        mode = "symlink";
+      };
+
+      foo3 = {
+        text = "boo!";
+        mode = "0700";
+        user = "root";
+        group = "root";
+      };
+
+      "a/nested/example/foo3" = {
+        text = "boo!";
+        mode = "0764";
+        user = "root";
+        group = "root";
+      };
+
+      "a/nested/example2/foo3" = {
+        text = "boo!";
+        mode = "0764";
+        user = "root";
+        group = "root";
+      };
+
+      out-of-store = {
+        source = "/run/systemd/system/";
+      };
+    };
+    systemd.services =
+      lib.listToAttrs
+        (lib.flip lib.genList 10 (ix:
+          lib.nameValuePair "service-${toString ix}"
+            {
+              enable = true;
+              description = "service-${toString ix}";
+              wants = [ "network-online.target" ];
+              after = [
+                "network-online.target"
+                "avahi-daemon.service"
+                "chrony.service"
+                "nss-lookup.target"
+                "tinc.service"
+                "pulseaudio.service"
+              ];
+              serviceConfig = {
+                Type = "oneshot";
+                RemainAfterExit = true;
+                ExecReload = "${lib.getBin pkgs.coreutils}/bin/true";
+              };
+              wantedBy = [ "multi-user.target" ];
+              requiredBy = lib.mkIf (ix > 5) [ "service-0.service" ];
+              script = ''
+                sleep ${if ix > 5 then "2" else "1"}
+              '';
+            })
+        );
+  };
+}