ObjectBase, Object, Interface: Fix move constructors and move assignments

* glib/glibmm/interface.cc: Don't call ObjectBase's move assignment operator
from Interface's move assignment operator.
* glib/glibmm/object.cc: Perform of job of sigc::trackable's move constructor
in Object's move constructor.
* glib/glibmm/objectbase.cc: Move constructor: Set gobject_ = nullptr.
Fix the assignment of cpp_destruction_in_progress_.
Move assignment: Add self-assignment guard. Avoid the risk of accidentally
deleting *this. Let a call to initialize_move() do most of the job.
* tests/glibmm_interface_move/main.cc:
* tests/glibmm_object_move/main.cc:
* tests/glibmm_objectbase_move/main.cc: Really test move assignment.
Test that the wrapped C object has been moved, and not copied.
Bug #756962.

3 files changed, 37 insertions, 23 deletions

diff --git a/tests/glibmm_interface_move/main.cc b/tests/glibmm_interface_move/main.cc
index 29662e99..28b8e8fb 100644
--- a/tests/glibmm_interface_move/main.cc
+++ b/tests/glibmm_interface_move/main.cc
@@ -106,7 +106,7 @@ protected:
 
 public:
   //A real application would never make the constructor public.
-  //It would instead have a protectd constructor and a public create() method.
+  //It would instead have a protected constructor and a public create() method.
   TestInterface(GObject* gobject, int i)
   : Glib::Interface(gobject),
     i_(i)
@@ -220,7 +220,10 @@ private:
 
 DerivedObject::CppClassType DerivedObject::derived_object_class_; // initialize static member
 
-/* TODO: Shouldn't this work too?
+/* Shouldn't this work too?
+ * No, because Glib::Interface::Interface(Interface&& src) does not call
+ * Glib::ObjectBase::initialize_move(), and Glib::Interface::operator=(Interface&& src)
+ * does not call Glib::ObjectBase::operator=(std::move(src)).
 static
 void test_interface_move_constructor()
 {
@@ -258,11 +261,13 @@ void test_object_with_interface_move_constructor()
 {
   DerivedObject derived(5);
   g_assert_cmpint(derived.i_, ==, 5);
-  GObject *gobject = derived.gobj();
+  GObject* gobject = derived.gobj();
   g_assert(derived.gobj() == gobject);
+
   DerivedObject derived2(std::move(derived));
   g_assert_cmpint(derived2.i_, ==, 5);
   g_assert(derived2.gobj() == gobject);
+  g_assert(derived.gobj() == nullptr);
 }
 
 static
@@ -270,11 +275,14 @@ void test_object_with_interface_move_assignment_operator()
 {
   DerivedObject derived(5);
   g_assert_cmpint(derived.i_, ==, 5);
-  GObject *gobject = derived.gobj();
+  GObject* gobject = derived.gobj();
   g_assert(derived.gobj() == gobject);
-  DerivedObject derived2 = std::move(derived);
+
+  DerivedObject derived2(6);
+  derived2 = std::move(derived);
   g_assert_cmpint(derived2.i_, ==, 5);
   g_assert(derived2.gobj() == gobject);
+  g_assert(derived.gobj() == nullptr);
 }
 
 
diff --git a/tests/glibmm_object_move/main.cc b/tests/glibmm_object_move/main.cc
index a62bcf9e..7868b176 100644
--- a/tests/glibmm_object_move/main.cc
+++ b/tests/glibmm_object_move/main.cc
@@ -2,7 +2,7 @@
 #include <iostream>
 #include <stdlib.h>
 
-//A basic derived GObject, just to test Glib::ObjectBase.
+//A basic derived GObject, just to test Glib::Object.
 typedef struct {
     GObject parent;
 } TestDerived;
@@ -27,7 +27,7 @@ class DerivedObject : public Glib::Object
 {
 public:
   //A real application would never make the constructor public.
-  //It would instead have a protectd constructor and a public create() method.
+  //It would instead have a protected constructor and a public create() method.
   DerivedObject(GObject* gobject, int i)
   : Glib::Object(gobject),
     i_(i)
@@ -56,32 +56,34 @@ public:
 static
 void test_object_move_constructor()
 {
-  GObject *gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
-  g_object_ref(gobject);
-
+  GObject* gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
   DerivedObject derived(gobject, 5);
   std::cout << "debug: gobj(): " << derived.gobj() << std::endl;
   g_assert(derived.gobj() == gobject);
+
   DerivedObject derived2(std::move(derived));
   g_assert_cmpint(derived2.i_, ==, 5);
   std::cout << "debug: gobj(): " << derived2.gobj() << std::endl;
   g_assert(derived2.gobj() == gobject);
+  g_assert(derived.gobj() == nullptr);
 }
 
 
 static
 void test_object_move_assignment_operator()
 {
-  GObject *gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
-  g_object_ref(gobject);
-
+  GObject* gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
   DerivedObject derived(gobject, 5);
   //std::cout << "debug: gobj(): " << derived.gobj() << std::endl;
   g_assert(derived.gobj() == gobject);
-  DerivedObject derived2 = std::move(derived);
+
+  GObject* gobject2 = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
+  DerivedObject derived2(gobject2, 6);
+  derived2 = std::move(derived);
   g_assert_cmpint(derived2.i_, ==, 5);
   //std::cout << "debug: gobj(): " << derived2.gobj() << std::endl;
   g_assert(derived2.gobj() == gobject);
+  g_assert(derived.gobj() == nullptr);
 }
 
 
diff --git a/tests/glibmm_objectbase_move/main.cc b/tests/glibmm_objectbase_move/main.cc
index ed71fe17..e70ff3bb 100644
--- a/tests/glibmm_objectbase_move/main.cc
+++ b/tests/glibmm_objectbase_move/main.cc
@@ -28,7 +28,7 @@ class DerivedObjectBase : public Glib::ObjectBase
 {
 public:
   //A real application would never make the constructor public.
-  //It would instead have a protectd constructor and a public create() method.
+  //It would instead have a protected constructor and a public create() method.
   DerivedObjectBase(GObject* gobject, int i)
   : Glib::ObjectBase(nullptr),
     i_(i)
@@ -42,7 +42,9 @@ public:
   DerivedObjectBase(DerivedObjectBase&& src) noexcept
   : Glib::ObjectBase(std::move(src)),
     i_(std::move(src.i_))
-  {}
+  {
+    ObjectBase::initialize_move(src.gobject_, &src);
+  }
 
   DerivedObjectBase& operator=(DerivedObjectBase&& src) noexcept
   {
@@ -58,31 +60,33 @@ public:
 static
 void test_objectbase_move_constructor()
 {
-  GObject *gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
-  g_object_ref(gobject);
-
+  GObject* gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
   DerivedObjectBase derived(gobject, 5);
   //std::cout << "debug: gobj(): " << derived.gobj() << std::endl;
   g_assert(derived.gobj() == gobject);
+
   DerivedObjectBase derived2(std::move(derived));
   g_assert_cmpint(derived2.i_, ==, 5);
   //std::cout << "debug: gobj(): " << derived2.gobj() << std::endl;
   g_assert(derived2.gobj() == gobject);
+  g_assert(derived.gobj() == nullptr);
 }
 
 static
 void test_objectbase_move_assignment_operator()
 {
-  GObject *gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
-  g_object_ref(gobject);
-
+  GObject* gobject = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
   DerivedObjectBase derived(gobject, 5);
   //std::cout << "debug: gobj(): " << derived.gobj() << std::endl;
   g_assert(derived.gobj() == gobject);
-  DerivedObjectBase derived2 = std::move(derived);
+
+  GObject* gobject2 = G_OBJECT(g_object_new(TEST_TYPE_DERIVED, nullptr));
+  DerivedObjectBase derived2(gobject2, 6);
+  derived2 = std::move(derived);
   g_assert_cmpint(derived2.i_, ==, 5);
   //std::cout << "debug: gobj(): " << derived2.gobj() << std::endl;
   g_assert(derived2.gobj() == gobject);
+  g_assert(derived.gobj() == nullptr);
 }
 
 int main(int, char**)