From ba9e3c3066ddc19a711287a99a67edd2ad0c4322 Mon Sep 17 00:00:00 2001
From: Gabriel Arazas <foodogsquared@foodogsquared.one>
Date: Wed, 26 Mar 2025 14:27:54 +0800
Subject: [PATCH] lib: init formats subset

---
 lib/default.nix |  4 ++++
 lib/formats.nix | 21 +++++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 lib/formats.nix

diff --git a/lib/default.nix b/lib/default.nix
index 24160a23..5fce7623 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -15,6 +15,10 @@ in pkgs.lib.makeExtensible (self:
     math = callLib ./math.nix;
     xdg = callLib ./xdg.nix;
 
+    # Just like from its inspiration, this contains Nix-representable data
+    # formats and won't have any attributes exported at the top-level.
+    formats = callLib ./formats.nix;
+
     # For future references, these are the only attributes that are going to be
     # exported as part of nixpkgs overlay.
     fetchers = callLib ./fetchers;
diff --git a/lib/formats.nix b/lib/formats.nix
new file mode 100644
index 00000000..41f25344
--- /dev/null
+++ b/lib/formats.nix
@@ -0,0 +1,21 @@
+{ lib, pkgs, self }:
+
+{
+  # The gnome-session config files uses one from GLib. See the following link
+  # at <https://docs.gtk.org/glib/struct.KeyFile.html> for details about the
+  # keyfile formatting and possibly the Desktop Entry specification at
+  # <https://freedesktop.org/wiki/Specifications/desktop-entry-spec>.
+  glibKeyfile = {}: {
+    type = with lib.types;
+      let
+        valueType = oneOf [ bool float int str (listOf valueType) ] // {
+          description =
+            "GLib keyfile atom (bool, int, float, string, or a list of the previous atoms)";
+        };
+      in attrsOf (attrsOf valueType);
+
+    generate = name: value:
+      pkgs.callPackage
+      ({ lib, writeText }: writeText name (lib.generators.toDconfINI value));
+  };
+}