goocanvas2: add updateScript

pkgs/development/libraries/goocanvas/2.x.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl, pkg-config, gettext, gtk-doc, gobject-introspection, python2, gtk3, cairo, glib }:
+{ lib, stdenv, fetchurl, pkg-config, gettext, gtk-doc, gobject-introspection, python2, gtk3, cairo, glib, gnome }:
 
 stdenv.mkDerivation rec {
   pname = "goocanvas";
@@ -20,6 +20,15 @@ stdenv.mkDerivation rec {
   PKG_CONFIG_GOBJECT_INTROSPECTION_1_0_GIRDIR = "$(dev)/share/gir-1.0";
   PKG_CONFIG_GOBJECT_INTROSPECTION_1_0_TYPELIBDIR = "$(out)/lib/girepository-1.0";
 
+  passthru = {
+    updateScript = gnome.updateScript {
+      attrPath = "${pname}${lib.versions.major version}";
+      packageName = pname;
+      versionPolicy = "odd-unstable";
+      freeze = true;
+    };
+  };
+
   meta = with lib; {
     description = "Canvas widget for GTK based on the the Cairo 2D library";
     homepage = "https://wiki.gnome.org/Projects/GooCanvas";