coalescing code for imports

lib/default.nix

@@ -0,0 +1,64 @@
+inputs:
+
+let
+  lib = inputs.nixpkgs.lib;
+in
+
+lib
+// rec {
+
+  filesInDirectoryWithSuffix =
+    directory: suffix:
+    lib.pipe (lib.filesystem.listFilesRecursive directory) [
+      # Get only files ending in .nix
+      (builtins.filter (name: lib.hasSuffix suffix name))
+    ];
+
+  # Returns all files ending in .nix for a directory
+  nixFiles = directory: filesInDirectoryWithSuffix directory ".nix";
+
+  # Returns all files ending in default.nix for a directory
+  defaultFiles = directory: filesInDirectoryWithSuffix directory "default.nix";
+
+  # Imports all files in a directory and passes inputs
+  importOverlays =
+    directory:
+    lib.pipe (nixFiles directory) [
+      # Import each overlay file
+      (map (file: (import file) inputs))
+    ];
+
+  # Import default files as attrset with keys provided by parent directory
+  defaultFilesToAttrset =
+    directory:
+    lib.pipe (defaultFiles directory) [
+      # Import each file
+      (map (file: {
+        name = builtins.baseNameOf (builtins.dirOf file);
+        value = import file;
+      }))
+      # Convert to an attrset of parent dir name -> file
+      (builtins.listToAttrs)
+    ];
+
+  # [ package1/package.nix package2/package.nix package2/hello.sh ]
+  buildPkgsFromDirectoryAndPkgs =
+    directory: pkgs:
+    lib.pipe (filesInDirectoryWithSuffix directory "package.nix") [
+
+      # Apply callPackage to create a derivation
+      # Must use final.callPackage to avoid infinite recursion
+      # [ package1.drv package2.drv ]
+      (builtins.map (name: pkgs.callPackage name { }))
+
+      # Convert the list to an attrset with keys from pname or name attr
+      # { package1 = package1.drv, package2 = package2.drv }
+      (builtins.listToAttrs (
+        map (v: {
+          name = v."pname" or v."name";
+          value = v;
+        })
+      ))
+    ];
+
+}