astal: move source to a separate package

It provides general description for all astal packages and r-ryantm
will create properly named PRs.

pkgs/development/libraries/astal/buildAstalModule.nix

@@ -1,7 +1,7 @@
 {
   lib,
   stdenv,
-  fetchFromGitHub,
+  source, # this is ./source.nix
 
   glib,
   wrapGAppsHook3,
@@ -39,17 +39,12 @@ let
       cleanArgs args
       // {
         pname = "astal-${name}";
-        version = "0-unstable-2025-03-21";
+        inherit (source) version;
 
         __structuredAttrs = true;
         strictDeps = true;
 
-        src = fetchFromGitHub {
+        src = source;
-          owner = "Aylur";
-          repo = "astal";
-          rev = "dc0e5d37abe9424c53dcbd2506a4886ffee6296e";
-          hash = "sha256-5WgfJAeBpxiKbTR/gJvxrGYfqQRge5aUDcGKmU1YZ1Q=";
-        };
 
         sourceRoot = "${finalAttrs.src.name}/${sourceRoot}";
 

pkgs/development/libraries/astal/default.nix

@@ -1,5 +1,6 @@
 { wireplumber }:
 self: {
+  source = self.callPackage ./source.nix { };
   buildAstalModule = self.callPackage ./buildAstalModule.nix { };
 
   apps = self.callPackage ./modules/apps.nix { };

pkgs/development/libraries/astal/modules/io.nix

@@ -1,17 +1,6 @@
-{ buildAstalModule, nix-update-script }:
+{ buildAstalModule }:
-(buildAstalModule {
+buildAstalModule {
   name = "io";
   sourceRoot = "lib/astal/io";
-  meta = {
+  meta.description = "Astal core library";
-    description = "Astal core library";
+}
-    longDescription = ''
-      Astal is a collection of building blocks for creating custom desktop shells
-    '';
-    mainProgram = "astal";
-  };
-}).overrideAttrs
-  {
-    # add an update script only in one place,
-    # so r-ryantm won't run it multiple times
-    passthru.updateScript = nix-update-script { extraArgs = [ "--version=branch" ]; };
-  }

pkgs/development/libraries/astal/source.nix

@@ -0,0 +1,33 @@
+{
+  lib,
+  nix-update-script,
+  fetchFromGitHub,
+}:
+(fetchFromGitHub {
+  owner = "Aylur";
+  repo = "astal";
+  rev = "dc0e5d37abe9424c53dcbd2506a4886ffee6296e";
+  hash = "sha256-5WgfJAeBpxiKbTR/gJvxrGYfqQRge5aUDcGKmU1YZ1Q=";
+}).overrideAttrs
+  (
+    final: prev: {
+      name = "${final.pname}-${final.version}"; # fetchFromGitHub already defines name
+      pname = "astal-source";
+      version = "0-unstable-2025-03-21";
+
+      meta = prev.meta // {
+        description = "Building blocks for creating custom desktop shells (source)";
+        longDescription = ''
+          Please don't use this package directly, use one of subpackages in
+          `astal` namespace. This package is just a `fetchFromGitHub`, which is
+          reused between all subpackages.
+        '';
+        maintainers = with lib.maintainers; [ perchun ];
+        platforms = lib.platforms.linux;
+      };
+
+      passthru = prev.passthru // {
+        updateScript = nix-update-script { extraArgs = [ "--version=branch" ]; };
+      };
+    }
+  )