Implement nix/findFileRecursive.nix for efficiency

Author: bladyjoker

flake.nix

@@ -32,11 +32,11 @@
     let
       inherit (nixpkgs) lib;
       # Collect all the build.nix files (flake-parts module)
-      buildDotNixes =
-        with builtins;
-        filter (lib.hasSuffix "build.nix") (
-          lib.filesystem.listFilesRecursive (filterSource (_path: _type: true) ./.) # NOTE(bladyjoker): This is here to prevent errors due to invalid Nix store filenames (spaces, commas, etc.)
-        );
+      buildDotNixes = import ./nix/findFilesRecursive.nix {
+        inherit lib;
+        toInclude = lib.hasSuffix "build.nix";
+        dir = ./.;
+      };
     in
     flake-parts.lib.mkFlake { inherit inputs; } {
 

nix/findFilesRecursive.nix

@@ -0,0 +1,28 @@
+# NOTE(bladyjoker): Sadly needed because the repo contains files and directories that are invalid Nix Store path names
+# TODO(bladyjoker): If the repo adjusts the naming scheme one can simply use lib.filesystem.listFilesRecursive
+{
+  lib,
+  toInclude,
+  dir,
+}:
+let
+  # Regex for characters allowed in Nix store paths:
+  # Alphanumeric, dots (.), underscores (_), plus (+), and hyphens (-)
+  isValidName = name: builtins.match "[a-zA-Z0-9._+-]+" name != null;
+
+  internalFunc =
+    dir:
+    (lib.mapAttrsToList (
+      name: type:
+      if isValidName name then
+        if type == "directory" then
+          internalFunc (dir + "/${name}")
+        else if toInclude name then
+          [ (dir + "/${name}") ]
+        else
+          [ ]
+      else
+        [ ]
+    ) (builtins.readDir dir));
+in
+lib.flatten (internalFunc dir)