gnujump: install desktop file

pkgs/games/gnujump/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl, SDL, SDL_image, SDL_mixer }:
+{ lib, stdenv, makeDesktopItem, copyDesktopItems, fetchurl, SDL, SDL_image, SDL_mixer }:
 
 stdenv.mkDerivation rec {
   pname = "gnujump";
@@ -7,10 +7,25 @@ stdenv.mkDerivation rec {
     url = "mirror://gnu/gnujump/${pname}-${version}.tar.gz";
     sha256 = "05syy9mzbyqcfnm0hrswlmhwlwx54f0l6zhcaq8c1c0f8dgzxhqk";
   };
+
+  nativeBuildInputs = [ copyDesktopItems ];
   buildInputs = [ SDL SDL_image SDL_mixer ];
 
   NIX_LDFLAGS = "-lm";
 
+  desktopItems = [ (makeDesktopItem {
+    name = "gnujump";
+    exec = "gnujump";
+    icon = "gnujump";
+    desktopName = "GNUjump";
+    comment     = "Jump up the tower to survive";
+    categories  = "Game;ArcadeGame;";
+  }) ];
+
+  postInstall = ''
+    install -Dm644 ${./gnujump.xpm} $out/share/pixmaps/gnujump.xpm
+  '';
+
   meta = with lib; {
     homepage = "https://jump.gnu.sinusoid.es/index.php?title=Main_Page";
     description = "A clone of the simple yet addictive game Xjump";