[glib] Fix binding properties of the same object

[Matthias Clasen <matthiasc src gnome org>]

commit 1426a8ca07f3ad0e874c0b0aad241ae93cf1e144
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Mar 4 20:49:04 2012 -0500

    Fix binding properties of the same object
    
    This problem was pointed out in bug 639873.
    The patch here is based on Matt Barnes patch,
    I've added a testcase as well.

 gobject/gbinding.c      |    8 +++++---
 gobject/tests/binding.c |   36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 3 deletions(-)
---
diff --git a/gobject/gbinding.c b/gobject/gbinding.c
index 612ed3b..3dbe616 100644
--- a/gobject/gbinding.c
+++ b/gobject/gbinding.c
@@ -575,9 +575,11 @@ g_binding_constructed (GObject *gobject)
                                                G_CALLBACK (on_target_notify),
                                                binding);
 
-  g_object_weak_ref (binding->target, weak_unbind, binding);
-  add_binding_qdata (binding->target, binding);
-
+  if (binding->target != binding->source)
+    {
+      g_object_weak_ref (binding->target, weak_unbind, binding);
+      add_binding_qdata (binding->target, binding);
+    }
 }
 
 static void
diff --git a/gobject/tests/binding.c b/gobject/tests/binding.c
index 7f6716b..afa7eb9 100644
--- a/gobject/tests/binding.c
+++ b/gobject/tests/binding.c
@@ -7,6 +7,7 @@ typedef struct _BindingSource
   GObject parent_instance;
 
   gint foo;
+  gint bar;
   gdouble value;
   gboolean toggle;
 } BindingSource;
@@ -21,6 +22,7 @@ enum
   PROP_SOURCE_0,
 
   PROP_SOURCE_FOO,
+  PROP_SOURCE_BAR,
   PROP_SOURCE_VALUE,
   PROP_SOURCE_TOGGLE
 };
@@ -42,6 +44,10 @@ binding_source_set_property (GObject      *gobject,
       source->foo = g_value_get_int (value);
       break;
 
+    case PROP_SOURCE_BAR:
+      source->bar = g_value_get_int (value);
+      break;
+
     case PROP_SOURCE_VALUE:
       source->value = g_value_get_double (value);
       break;
@@ -69,6 +75,10 @@ binding_source_get_property (GObject    *gobject,
       g_value_set_int (value, source->foo);
       break;
 
+    case PROP_SOURCE_BAR:
+      g_value_set_int (value, source->bar);
+      break;
+
     case PROP_SOURCE_VALUE:
       g_value_set_double (value, source->value);
       break;
@@ -95,6 +105,11 @@ binding_source_class_init (BindingSourceClass *klass)
                                                      -1, 100,
                                                      0,
                                                      G_PARAM_READWRITE));
+  g_object_class_install_property (gobject_class, PROP_SOURCE_BAR,
+                                   g_param_spec_int ("bar", "Bar", "Bar",
+                                                     -1, 100,
+                                                     0,
+                                                     G_PARAM_READWRITE));
   g_object_class_install_property (gobject_class, PROP_SOURCE_VALUE,
                                    g_param_spec_double ("value", "Value", "Value",
                                                         -100.0, 200.0,
@@ -532,6 +547,26 @@ binding_invert_boolean (void)
   g_object_unref (target);
 }
 
+static void
+binding_same_object (void)
+{
+  BindingSource *source = g_object_new (binding_source_get_type (),
+                                        "foo", 100,
+                                        "bar", 50,
+                                        NULL);
+  GBinding *binding G_GNUC_UNUSED;
+
+  binding = g_object_bind_property (source, "foo",
+                                    source, "bar",
+                                    G_BINDING_BIDIRECTIONAL);
+
+  g_object_set (source, "foo", 10, NULL);
+  g_assert_cmpint (source->foo, ==, 10);
+  g_assert_cmpint (source->bar, ==, 10);
+
+  g_object_unref (source);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -548,6 +583,7 @@ main (int argc, char *argv[])
   g_test_add_func ("/binding/chain", binding_chain);
   g_test_add_func ("/binding/sync-create", binding_sync_create);
   g_test_add_func ("/binding/invert-boolean", binding_invert_boolean);
+  g_test_add_func ("/binding/same-object", binding_same_object);
 
   return g_test_run ();
 }