[glib/wip/kalev/recursive-mutex-locker: 2/2] tests: Update GMutexLocker tests

[Kalev Lember <klember src gnome org>]

commit 924cb8f2a6db8dc8993402849c6c9645d4628cbf
Author: Kalev Lember <klember redhat com>
Date:   Fri Dec 14 17:30:58 2018 +0100

    tests: Update GMutexLocker tests
    
    Spawn a thread and assert that the mutex actually got locked, same as we
    do in GRecMutexLocker tests.

 glib/tests/autoptr.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)
---
diff --git a/glib/tests/autoptr.c b/glib/tests/autoptr.c
index 8472ca9bb..465e4f473 100644
--- a/glib/tests/autoptr.c
+++ b/glib/tests/autoptr.c
@@ -329,6 +329,14 @@ test_g_mutex (void)
   g_mutex_init (&val);
 }
 
+static gpointer
+mutex_locked_thread (gpointer data)
+{
+  GMutex *mutex = (GMutex *) data;
+  g_assert_false (g_mutex_trylock (mutex));
+  return NULL;
+}
+
 static void
 test_g_mutex_locker (void)
 {
@@ -339,8 +347,13 @@ test_g_mutex_locker (void)
   if (TRUE)
     {
       g_autoptr(GMutexLocker) val = g_mutex_locker_new (&mutex);
+      GThread *thread;
       
-      g_assert (val != NULL);
+      g_assert_nonnull (val);
+
+      /* verify that the mutex is actually locked */
+      thread = g_thread_new ("mutex locked", mutex_locked_thread, &mutex);
+      g_thread_join (thread);
     }
 }