tests: add signal disconnection test

This commit adds a test to ensure that during a signal emission, if
a signal handler gets disconnected, it won't be run, even if it would
have run before the disconnection.

tests/gobject/Makefile.am

@@ -19,6 +19,7 @@ installed_test_programs = \
 	defaultiface				\
 	dynamictype				\
 	override				\
+	signals					\
 	singleton				\
 	references				\
 	$(NULL)
@@ -39,6 +40,7 @@ TESTS_ENVIRONMENT = \
 	MALLOC_PERTURB_=$$(($${RANDOM:-256} % 256))
 
 accumulator_SOURCES = accumulator.c testmarshal.c testmarshal.h
+signals_SOURCES = signals.c
 defaultiface_SOURCES = defaultiface.c testmodule.c testmodule.h
 dynamictype_SOURCES = dynamictype.c testmodule.c testmodule.h
 

tests/gobject/signals.c

@@ -0,0 +1,135 @@
+/* GObject - GLib Type, Object, Parameter and Signal Library
+ * Copyright (C) 2013 Red Hat, Inc.
+ * Copy and pasted from accumulator.c and modified.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#undef        G_LOG_DOMAIN
+#define       G_LOG_DOMAIN "TestSignals"
+
+#undef G_DISABLE_ASSERT
+#undef G_DISABLE_CHECKS
+#undef G_DISABLE_CAST_CHECKS
+
+#include <glib-object.h>
+
+#include "testcommon.h"
+
+/* What this test tests is the behavior of signal disconnection
+ * from within a signal handler for the signal being disconnected.
+ *
+ * The test demonstrates that signal handlers disconnected from a signal
+ * from an earlier handler in the same emission will not be run.
+ *
+ * It also demonstrates that signal handlers connected from a signal
+ * from an earlier handler in the same emission will not be run.
+ */
+
+/*
+ * TestObject, a parent class for TestObject
+ */
+#define TEST_TYPE_OBJECT         (test_object_get_type ())
+typedef struct _TestObject        TestObject;
+typedef struct _TestObjectClass   TestObjectClass;
+static gboolean callback1_ran = FALSE, callback2_ran = FALSE, callback3_ran = FALSE, default_handler_ran = FALSE;
+
+struct _TestObject
+{
+  GObject parent_instance;
+};
+struct _TestObjectClass
+{
+  GObjectClass parent_class;
+
+  void   (*test_signal) (TestObject *object);
+};
+
+static GType test_object_get_type (void);
+
+static void
+test_object_real_signal (TestObject *object)
+{
+  default_handler_ran = TRUE;
+}
+
+static void
+test_object_signal_callback3 (TestObject *object,
+                              gpointer    data)
+{
+  callback3_ran = TRUE;
+}
+
+static void
+test_object_signal_callback2 (TestObject *object,
+                              gpointer    data)
+{
+  callback2_ran = TRUE;
+}
+
+static void
+test_object_signal_callback1 (TestObject *object,
+                              gpointer    data)
+{
+  callback1_ran = TRUE;
+  g_signal_handlers_disconnect_by_func (G_OBJECT (object),
+                                        test_object_signal_callback2,
+                                        data);
+  g_signal_connect (object, "test-signal",
+                    G_CALLBACK (test_object_signal_callback3), NULL);
+}
+
+static void
+test_object_class_init (TestObjectClass *class)
+{
+  class->test_signal = test_object_real_signal;
+
+  g_signal_new ("test-signal",
+                G_OBJECT_CLASS_TYPE (class),
+                G_SIGNAL_RUN_LAST,
+                G_STRUCT_OFFSET (TestObjectClass, test_signal),
+                NULL, NULL, NULL, G_TYPE_NONE, 0);
+}
+
+static DEFINE_TYPE(TestObject, test_object,
+                   test_object_class_init, NULL, NULL,
+                   G_TYPE_OBJECT)
+
+int
+main (int   argc,
+      char *argv[])
+{
+  TestObject *object;
+
+  g_log_set_always_fatal (g_log_set_always_fatal (G_LOG_FATAL_MASK) |
+                          G_LOG_LEVEL_WARNING |
+                          G_LOG_LEVEL_CRITICAL);
+
+  object = g_object_new (TEST_TYPE_OBJECT, NULL);
+
+  g_signal_connect (object, "test-signal",
+                    G_CALLBACK (test_object_signal_callback1), NULL);
+  g_signal_connect (object, "test-signal",
+                    G_CALLBACK (test_object_signal_callback2), NULL);
+  g_signal_emit_by_name (object, "test-signal");
+
+  g_assert (callback1_ran);
+  g_assert (!callback2_ran);
+  g_assert (!callback3_ran);
+  g_assert (default_handler_ran);
+
+  return 0;
+}