From 91296169197b12e268fabd89bf966dfeabe67719 Mon Sep 17 00:00:00 2001
From: Jan Tojnar <jtojnar@gmail.com>
Date: Mon, 2 Dec 2019 17:23:02 +0100
Subject: [PATCH] nixos/pantheon fix GNOME_SESSION_DEBUG conflict

When session debugging was enabled in GNOME but not in Pantheon

	{
	  services.xserver = {
	    desktopManager.pantheon = {
	      enable = true;
	    };
	    desktopManager.gnome3 = {
	      enable = true;
	      debug = true;
	    };
	  };
	}

it caused a conflict:

	error: The option `environment.sessionVariables.GNOME_SESSION_DEBUG' has conflicting definitions, in `<nixpkgs/nixos/modules/services/x11/desktop-managers/pantheon.nix>' and `<nixpkgs/nixos/modules/services/x11/desktop-managers/gnome3.nix>'.
---
 nixos/modules/services/x11/desktop-managers/pantheon.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nixos/modules/services/x11/desktop-managers/pantheon.nix b/nixos/modules/services/x11/desktop-managers/pantheon.nix
index 80dab135ee26..25ef1cbfc67e 100644
--- a/nixos/modules/services/x11/desktop-managers/pantheon.nix
+++ b/nixos/modules/services/x11/desktop-managers/pantheon.nix
@@ -159,7 +159,7 @@ in
     # Override GSettings schemas
     environment.sessionVariables.NIX_GSETTINGS_OVERRIDES_DIR = "${nixos-gsettings-desktop-schemas}/share/gsettings-schemas/nixos-gsettings-overrides/glib-2.0/schemas";
 
-    environment.sessionVariables.GNOME_SESSION_DEBUG = optionalString cfg.debug "1";
+    environment.sessionVariables.GNOME_SESSION_DEBUG = mkIf cfg.debug "1";
 
     # Settings from elementary-default-settings
     environment.sessionVariables.GTK_CSD = "1";