tests: Accept warnings when initializing mutter

Initializing mutter, might cause warning such as the `failed to bind to` when
another XServer is running. However these warnings are not critical, so we can
safely ignore them.

src/tests/headless-start-test.c

@@ -191,8 +191,7 @@ main (int argc, char *argv[])
                                           META_TYPE_BACKEND_TEST);
   meta_wayland_override_display_name ("mutter-test-display");
 
-  meta_init ();
+  test_meta_init ();
-  meta_register_with_session ();
 
   g_idle_add (run_tests, NULL);
 

src/tests/test-runner.c

@@ -799,8 +799,7 @@ main (int argc, char **argv)
   meta_plugin_manager_load (test_get_plugin_name ());
   meta_wayland_override_display_name ("mutter-test-display");
 
-  meta_init ();
+  test_meta_init ();
-  meta_register_with_session ();
 
   RunTestsInfo info;
   info.tests = (char **)tests->pdata;

src/tests/test-utils.c

@@ -22,6 +22,7 @@
 #include "tests/test-utils.h"
 
 #include <gio/gio.h>
+#include <meta/main.h>
 #include <string.h>
 
 #include "core/display-private.h"
@@ -94,6 +95,21 @@ test_init (int    *argc,
   ensure_test_client_path (*argc, *argv);
 }
 
+void
+test_meta_init ()
+{
+  GLogLevelFlags log_flags;
+
+  /* Accept warnings in mutter initialization, as `failed to bind` one */
+  log_flags = g_log_set_always_fatal (G_LOG_FATAL_MASK);
+  g_log_set_always_fatal (log_flags & ~G_LOG_LEVEL_WARNING);
+
+  meta_init ();
+  meta_register_with_session ();
+
+  g_log_set_always_fatal (log_flags);
+}
+
 AsyncWaiter *
 async_waiter_new (void)
 {

src/tests/test-utils.h

@@ -43,6 +43,8 @@ typedef struct _TestClient TestClient;
 void test_init (int    *argc,
                 char ***argv);
 
+void test_meta_init (void);
+
 gboolean async_waiter_alarm_filter (AsyncWaiter           *waiter,
                                     MetaX11Display        *x11_display,
                                     XSyncAlarmNotifyEvent *event);

src/tests/unit-tests.c

@@ -265,8 +265,7 @@ main (int argc, char *argv[])
                                           META_TYPE_BACKEND_TEST);
   meta_wayland_override_display_name ("mutter-test-display");
 
-  meta_init ();
+  test_meta_init ();
-  meta_register_with_session ();
 
   g_idle_add (run_tests, NULL);