From 35279a22be2a7b77aac802b54d6542733c7ebfce Mon Sep 17 00:00:00 2001
From: cwyc <16950437+cwyc@users.noreply.github.com>
Date: Tue, 17 Aug 2021 04:06:25 -0400
Subject: [PATCH] gnome-backgrounds: stable image paths

This patch makes the backgrounds database point to stable paths in /run/current-system/sw that don't decay whenever this package's hash changes.
---
 pkgs/desktops/gnome/core/gnome-backgrounds/default.nix   | 7 +++++++
 .../gnome/core/gnome-backgrounds/stable-dir.patch        | 9 +++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 pkgs/desktops/gnome/core/gnome-backgrounds/stable-dir.patch

diff --git a/pkgs/desktops/gnome/core/gnome-backgrounds/default.nix b/pkgs/desktops/gnome/core/gnome-backgrounds/default.nix
index 370cd14e4677..f7a39d92cfb4 100644
--- a/pkgs/desktops/gnome/core/gnome-backgrounds/default.nix
+++ b/pkgs/desktops/gnome/core/gnome-backgrounds/default.nix
@@ -13,6 +13,13 @@ stdenv.mkDerivation rec {
     updateScript = gnome.updateScript { packageName = "gnome-backgrounds"; attrPath = "gnome.gnome-backgrounds"; };
   };
 
+  patches = [
+    # Makes the database point to stable paths in /run/current-system/sw/share, which don't decay whenever this package's hash changes.
+    # This assumes a nixos + gnome system, where this package is installed in environment.systemPackages,
+    # and /share outputs are included in environment.pathsToLink.
+    ./stable-dir.patch
+  ];
+
   nativeBuildInputs = [ meson ninja pkg-config gettext ];
 
   meta = with lib; {
diff --git a/pkgs/desktops/gnome/core/gnome-backgrounds/stable-dir.patch b/pkgs/desktops/gnome/core/gnome-backgrounds/stable-dir.patch
new file mode 100644
index 000000000000..cbc55e8a5c01
--- /dev/null
+++ b/pkgs/desktops/gnome/core/gnome-backgrounds/stable-dir.patch
@@ -0,0 +1,9 @@
+diff --git a/backgrounds/meson.build b/backgrounds/meson.build
+index 2175a16..cf521df 100644
+--- a/backgrounds/meson.build
++++ b/backgrounds/meson.build
+@@ -1,5 +1,5 @@
+ dataconf = configuration_data()
+-dataconf.set('BACKGROUNDDIR', backgrounddir)
++dataconf.set('BACKGROUNDDIR', '/run/current-system/sw/share/backgrounds/gnome')
+ dataconf.set('datadir', datadir)