test: add basic test for flakeModule functionality

nix/repo/flake.lock

@@ -17,9 +17,27 @@
         "type": "gitlab"
       }
     },
+    "nixtest-lib": {
+      "locked": {
+        "dir": "lib",
+        "lastModified": 1753957623,
+        "narHash": "sha256-kdImwKx57N0QL8HPUUb5ADwXFgSjaNOk39b/eKlzyTo=",
+        "owner": "TECHNOFAB",
+        "repo": "nixtest",
+        "rev": "22b43c9fe83be73c3f0648bbb54bc3c1cf7f96df",
+        "type": "gitlab"
+      },
+      "original": {
+        "dir": "lib",
+        "owner": "TECHNOFAB",
+        "repo": "nixtest",
+        "type": "gitlab"
+      }
+    },
     "root": {
       "inputs": {
         "devshell-lib": "devshell-lib",
+        "nixtest-lib": "nixtest-lib",
         "treefmt-nix": "treefmt-nix"
       }
     },

nix/repo/flake.nix

@@ -1,6 +1,7 @@
 {
   inputs = {
     devshell-lib.url = "gitlab:rensa-nix/devshell?dir=lib";
+    nixtest-lib.url = "gitlab:TECHNOFAB/nixtest?dir=lib";
     treefmt-nix = {
       url = "github:numtide/treefmt-nix";
       flake = false;
@@ -10,6 +11,7 @@
     i
     // {
       devshell = i.devshell-lib.lib {inherit (i.parent) pkgs;};
+      ntlib = i.nixtest-lib.lib {inherit (i.parent) pkgs;};
       cilib = import "${i.parent.self}/lib" {inherit (i.parent) pkgs;};
       treefmt = import i.treefmt-nix;
     };

nix/repo/tests.nix

@@ -0,0 +1,10 @@
+{inputs, ...}: let
+  inherit (inputs) pkgs ntlib cilib;
+in {
+  tests = ntlib.mkNixtest {
+    modules = ntlib.autodiscover {dir = "${inputs.self}/tests";};
+    args = {
+      inherit pkgs ntlib cilib;
+    };
+  };
+}