tests: use X11 Gdk backend in dummy app

Author: amezin

tests/dummy-app.js

@@ -6,9 +6,10 @@
 
 'use strict';
 
+imports.gi.versions.Gdk = '4.0';
 imports.gi.versions.Gtk = '4.0';
 
-const { GObject, Gio, Gtk } = imports.gi;
+const { GObject, Gio, Gdk, Gtk } = imports.gi;
 
 const System = imports.system;
 
@@ -19,6 +20,8 @@ const Application = GObject.registerClass({
 
         this.connect('startup', this.startup.bind(this));
         this.connect('activate', this.activate.bind(this));
+
+        Gdk.set_allowed_backends('x11');
     }
 
     startup() {

tests/fixtures.py

@@ -457,6 +457,19 @@ def shell_init(
             shell_test_hook.SetPointer(pointer_x, center_y)
             shell_test_hook.SetPointer(center_x, center_y)
 
+    @pytest.fixture(scope='class')
+    def shell_env(
+        self,
+        shell_init,
+        shell_test_hook
+    ):
+        shell_environ = shell_test_hook.Eval('imports.gi.GLib.get_environ()')
+
+        return {
+            k: v for k, _, v in
+            (entry.partition('=') for entry in shell_environ)
+        }
+
     @pytest.fixture(scope='class')
     def extension_init(self, shell_init, shell_extensions_dbus_interface):
         return shell_extensions_dbus_interface.EnableExtension('[email protected]')
@@ -592,13 +605,14 @@ def dummy_app(
         process_launcher,
         dbus_connection,
         shell_test_hook,
+        shell_env,
         hide_overview,
         pytestconfig,
     ):
         with process_launcher.spawn(
             str(pytestconfig.option.gjs),
             str(THIS_DIR / 'dummy-app.js'),
-            env=dbus_environment,
+            env=shell_env,
         ) as proc:
             try:
                 shell_test_hook.wait_property('FocusApp', 'com.github.ddterm.DummyApp')