listlistmodel: Drop item_type

We are using G_TYPE_OBJECT throughout, so there
is no need for GtkListListModel to do anything else.

Update all callers.

demos/constraint-editor/constraint-view.c

@@ -174,28 +174,29 @@ constraint_view_init (ConstraintView *self)
   manager = gtk_constraint_layout_new ();
   gtk_widget_set_layout_manager (GTK_WIDGET (self), manager);
 
-  all_children = gtk_widget_observe_children (GTK_WIDGET (self));
-  all_constraints = gtk_constraint_layout_observe_constraints (GTK_CONSTRAINT_LAYOUT (manager));
   guides = gtk_constraint_layout_observe_guides (GTK_CONSTRAINT_LAYOUT (manager));
+
+  all_constraints = gtk_constraint_layout_observe_constraints (GTK_CONSTRAINT_LAYOUT (manager));
   filter = gtk_custom_filter_new (omit_internal, NULL, NULL);
   constraints = (GListModel *)gtk_filter_list_model_new (all_constraints, filter);
   g_object_unref (filter);
+  g_object_unref (all_constraints);
+
+  all_children = gtk_widget_observe_children (GTK_WIDGET (self));
   filter = gtk_custom_filter_new (omit_internal, NULL, NULL);
   children = (GListModel *)gtk_filter_list_model_new (all_children, filter);
   g_object_unref (filter);
+  g_object_unref (all_children);
 
   list = g_list_store_new (G_TYPE_LIST_MODEL);
   g_list_store_append (list, children);
   g_list_store_append (list, guides);
   g_list_store_append (list, constraints);
-  self->model = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (list)));
   g_object_unref (children);
   g_object_unref (guides);
   g_object_unref (constraints);
-  g_object_unref (all_children);
-  g_object_unref (all_constraints);
-  g_object_unref (list);
 
+  self->model = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (list)));
 
   controller = (GtkEventController *)gtk_gesture_drag_new ();
   g_signal_connect (controller, "drag-begin", G_CALLBACK (drag_begin), self);

gtk/gtkcustompaperunixdialog.c

@@ -322,7 +322,6 @@ gtk_custom_paper_unix_dialog_init (GtkCustomPaperUnixDialog *dialog)
   g_object_unref (printer_list);
 
   full_list = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (printer_list_list)));
-  g_object_unref (printer_list_list);
 
   filter = gtk_custom_filter_new (match_func, NULL, NULL);
   dialog->printer_list = G_LIST_MODEL (gtk_filter_list_model_new (full_list, filter));

gtk/gtkflattenlistmodel.c

@@ -425,7 +425,7 @@ gtk_flatten_list_model_init (GtkFlattenListModel *self)
 
 /**
  * gtk_flatten_list_model_new:
- * @model: (nullable) (transfer none): the model to be flattened
+ * @model: (nullable) (transfer full): the model to be flattened
  *
  * Creates a new #GtkFlattenListModel that flattens @list.
  *
@@ -442,6 +442,9 @@ gtk_flatten_list_model_new (GListModel *model)
                          "model", model,
                          NULL);
 
+  /* we consume the reference */
+  g_clear_object (&model);
+
   return result;
 }
 

gtk/gtkfontchooserwidget.c

@@ -784,7 +784,7 @@ update_fontlist (GtkFontChooserWidget *self)
   if ((self->level & GTK_FONT_CHOOSER_LEVEL_STYLE) == 0)
     model = g_object_ref (G_LIST_MODEL (fontmap));
   else
-    model = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (fontmap)));
+    model = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (g_object_ref (fontmap))));
   gtk_filter_list_model_set_model (self->filter_model, model);
   g_object_unref (model);
 }

gtk/gtklistlistmodel.c

@@ -36,7 +36,6 @@ struct _GtkListListModel
 {
   GObject parent_instance;
 
-  GType item_type;
   guint n_items;
   gpointer (* get_first) (gpointer);
   gpointer (* get_next) (gpointer, gpointer);
@@ -55,9 +54,7 @@ struct _GtkListListModelClass
 static GType
 gtk_list_list_model_get_item_type (GListModel *list)
 {
-  GtkListListModel *self = GTK_LIST_LIST_MODEL (list);
-
-  return self->item_type;
+  return G_TYPE_OBJECT;
 }
 
 static guint
@@ -143,8 +140,7 @@ gtk_list_list_model_init (GtkListListModel *self)
 }
 
 GtkListListModel *
-gtk_list_list_model_new (GType          item_type,
-                         gpointer       (* get_first) (gpointer),
+gtk_list_list_model_new (gpointer       (* get_first) (gpointer),
                          gpointer       (* get_next) (gpointer, gpointer),
                          gpointer       (* get_previous) (gpointer, gpointer),
                          gpointer       (* get_last) (gpointer),
@@ -161,8 +157,7 @@ gtk_list_list_model_new (GType          item_type,
        item = get_next (item, data))
     n_items++;
 
-  return gtk_list_list_model_new_with_size (item_type,
-                                            n_items,
+  return gtk_list_list_model_new_with_size (n_items,
                                             get_first,
                                             get_next,
                                             get_previous,
@@ -173,8 +168,7 @@ gtk_list_list_model_new (GType          item_type,
 }
 
 GtkListListModel *
-gtk_list_list_model_new_with_size (GType          item_type,
-                                   guint          n_items,
+gtk_list_list_model_new_with_size (guint          n_items,
                                    gpointer       (* get_first) (gpointer),
                                    gpointer       (* get_next) (gpointer, gpointer),
                                    gpointer       (* get_previous) (gpointer, gpointer),
@@ -185,7 +179,6 @@ gtk_list_list_model_new_with_size (GType          item_type,
 {
   GtkListListModel *result;
 
-  g_return_val_if_fail (g_type_is_a (item_type, G_TYPE_OBJECT), NULL);
   g_return_val_if_fail (get_first != NULL, NULL);
   g_return_val_if_fail (get_next != NULL, NULL);
   g_return_val_if_fail (get_previous != NULL, NULL);
@@ -193,7 +186,6 @@ gtk_list_list_model_new_with_size (GType          item_type,
 
   result = g_object_new (GTK_TYPE_LIST_LIST_MODEL, NULL);
 
-  result->item_type = item_type;
   result->n_items = n_items;
   result->get_first = get_first;
   result->get_next = get_next;

gtk/gtklistlistmodelprivate.h

@@ -37,8 +37,7 @@ typedef struct _GtkListListModelClass GtkListListModelClass;
 
 GType                   gtk_list_list_model_get_type            (void) G_GNUC_CONST;
 
-GtkListListModel *      gtk_list_list_model_new                 (GType                   item_type,
-                                                                 gpointer                (* get_first) (gpointer),
+GtkListListModel *      gtk_list_list_model_new                 (gpointer                (* get_first) (gpointer),
                                                                  gpointer                (* get_next) (gpointer, gpointer),
                                                                  gpointer                (* get_previous) (gpointer, gpointer),
                                                                  gpointer                (* get_last) (gpointer),
@@ -46,8 +45,7 @@ GtkListListModel *      gtk_list_list_model_new                 (GType
                                                                  gpointer                data,
                                                                  GDestroyNotify          notify);
 
-GtkListListModel *      gtk_list_list_model_new_with_size       (GType                   item_type,
-                                                                 guint                   n_items,
+GtkListListModel *      gtk_list_list_model_new_with_size       (guint                   n_items,
                                                                  gpointer                (* get_first) (gpointer),
                                                                  gpointer                (* get_next) (gpointer, gpointer),
                                                                  gpointer                (* get_previous) (gpointer, gpointer),

gtk/gtkmaplistmodel.c

@@ -412,7 +412,7 @@ gtk_map_list_model_augment (GtkRbTree *map,
 
 /**
  * gtk_map_list_model_new:
- * @model: (allow-none): The model to map or %NULL for none
+ * @model: (transfer full) (allow-none): The model to map or %NULL for none
  * @map_func: (allow-none): map function or %NULL to not map items
  * @user_data: (closure): user data passed to @map_func
  * @user_destroy: destroy notifier for @user_data
@@ -435,6 +435,9 @@ gtk_map_list_model_new (GListModel             *model,
                          "model", model,
                          NULL);
 
+  /* consume the reference */
+  g_clear_object (&model);
+
   if (map_func)
     gtk_map_list_model_set_map_func (result, map_func, user_data, user_destroy);
 

gtk/gtkpagesetupunixdialog.c

@@ -308,7 +308,6 @@ gtk_page_setup_unix_dialog_init (GtkPageSetupUnixDialog *dialog)
   g_list_store_append (store, dialog->manage_papers_list);
   paper_size_list = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (store)));
   gtk_drop_down_set_model (GTK_DROP_DOWN (dialog->paper_size_combo), paper_size_list);
-  g_object_unref (store);
   g_object_unref (paper_size_list);
 
   /* Do this in code, we want the translatable strings without the markup */

gtk/gtkprintunixdialog.c

@@ -807,7 +807,6 @@ gtk_print_unix_dialog_init (GtkPrintUnixDialog *dialog)
   g_list_store_append (store, dialog->manage_papers_list);
   paper_size_list = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (store)));
   gtk_drop_down_set_model (GTK_DROP_DOWN (dialog->paper_size_combo), paper_size_list);
-  g_object_unref (store);
   g_object_unref (paper_size_list);
 
   /* Load backends */
@@ -1037,7 +1036,6 @@ load_print_backends (GtkPrintUnixDialog *dialog)
 {
   GList *node;
   GListStore *lists;
-  GListModel *model;
 
   lists = g_list_store_new (G_TYPE_LIST_MODEL);
 
@@ -1053,11 +1051,7 @@ load_print_backends (GtkPrintUnixDialog *dialog)
       g_list_store_append (lists, gtk_print_backend_get_printers (backend));
     }
 
-  model = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (lists)));
-
-  g_object_unref (lists);
-
-  return model;
+  return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (lists)));
 }
 
 static void

gtk/gtkshortcutmanager.c

@@ -44,21 +44,16 @@ G_DEFINE_INTERFACE (GtkShortcutManager, gtk_shortcut_manager, G_TYPE_OBJECT)
 void
 gtk_shortcut_manager_create_controllers (GtkWidget *widget)
 {
-  GListStore *store;
   GtkFlattenListModel *model;
   GtkEventController *controller;
 
-  store = g_list_store_new (GTK_TYPE_SHORTCUT_CONTROLLER);
-  model = gtk_flatten_list_model_new (G_LIST_MODEL (store));
-  g_object_unref (store);
+  model = gtk_flatten_list_model_new (G_LIST_MODEL (g_list_store_new (GTK_TYPE_SHORTCUT_CONTROLLER)));
   g_object_set_data_full (G_OBJECT (widget), "gtk-shortcut-manager-bubble", model, g_object_unref);
   controller = gtk_shortcut_controller_new_for_model (G_LIST_MODEL (model));
   gtk_event_controller_set_name (controller, "gtk-shortcut-manager-bubble");
   gtk_widget_add_controller (widget, controller);
 
-  store = g_list_store_new (GTK_TYPE_SHORTCUT_CONTROLLER);
-  model = gtk_flatten_list_model_new (G_LIST_MODEL (store));
-  g_object_unref (store);
+  model = gtk_flatten_list_model_new (G_LIST_MODEL (g_list_store_new (GTK_TYPE_SHORTCUT_CONTROLLER)));
   g_object_set_data_full (G_OBJECT (widget), "gtk-shortcut-manager-capture", model, g_object_unref);
   controller = gtk_shortcut_controller_new_for_model (G_LIST_MODEL (model));
   gtk_event_controller_set_name (controller, "gtk-shortcut-manager-capture");

gtk/gtkwidget.c

@@ -11535,8 +11535,7 @@ gtk_widget_observe_children (GtkWidget *widget)
   if (priv->children_observer)
     return g_object_ref (G_LIST_MODEL (priv->children_observer));
 
-  priv->children_observer = gtk_list_list_model_new (GTK_TYPE_WIDGET,
-                                                     (gpointer) gtk_widget_get_first_child,
+  priv->children_observer = gtk_list_list_model_new ((gpointer) gtk_widget_get_first_child,
                                                      (gpointer) gtk_widget_get_next_sibling,
                                                      (gpointer) gtk_widget_get_prev_sibling,
                                                      (gpointer) gtk_widget_get_last_child,
@@ -11622,14 +11621,13 @@ gtk_widget_observe_controllers (GtkWidget *widget)
   if (priv->controller_observer)
     return g_object_ref (G_LIST_MODEL (priv->controller_observer));
 
-  priv->controller_observer = gtk_list_list_model_new (GTK_TYPE_EVENT_CONTROLLER,
-                                                      gtk_widget_controller_list_get_first,
-                                                      gtk_widget_controller_list_get_next,
-                                                      gtk_widget_controller_list_get_prev,
-                                                      NULL,
-                                                      (gpointer) g_object_ref,
-                                                      widget,
-                                                      gtk_widget_controller_observer_destroyed);
+  priv->controller_observer = gtk_list_list_model_new (gtk_widget_controller_list_get_first,
+                                                       gtk_widget_controller_list_get_next,
+                                                       gtk_widget_controller_list_get_prev,
+                                                       NULL,
+                                                       (gpointer) g_object_ref,
+                                                       widget,
+                                                       gtk_widget_controller_observer_destroyed);
 
   return G_LIST_MODEL (priv->controller_observer);
 }

gtk/inspector/controllers.c

@@ -244,7 +244,6 @@ gtk_inspector_controllers_set_object (GtkInspectorControllers *self,
   gtk_property_lookup_list_model_set_object (self->model, object);
 
   map_model = gtk_map_list_model_new (G_LIST_MODEL (self->model), map_to_controllers, NULL, NULL);
-  g_object_unref (self->model);
 
   flatten_model = gtk_flatten_list_model_new (G_LIST_MODEL (map_model));
 
@@ -260,7 +259,6 @@ gtk_inspector_controllers_set_object (GtkInspectorControllers *self,
 
   g_object_unref (sort_model);
   g_object_unref (flatten_model);
-  g_object_unref (map_model);
 }
 
 static void

gtk/inspector/object-tree.c

@@ -116,7 +116,6 @@ static GListModel *
 object_tree_widget_get_children (GObject *object)
 {
   GtkWidget *widget = GTK_WIDGET (object);
-  GtkFlattenListModel *flatten;
   GListStore *list;
   GListModel *sublist;
 
@@ -130,10 +129,7 @@ object_tree_widget_get_children (GObject *object)
   g_list_store_append (list, sublist);
   g_object_unref (sublist);
 
-  flatten = gtk_flatten_list_model_new (G_LIST_MODEL (list));
-  g_object_unref (list);
-
-  return G_LIST_MODEL (flatten);
+  return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (list)));
 }
 
 static GListModel *
@@ -211,7 +207,6 @@ list_model_for_properties (GObject     *object,
                            const char **props)
 {
   GListStore *concat;
-  GListModel *result;
   guint i;
 
   if (props[1] == NULL)
@@ -225,9 +220,7 @@ list_model_for_properties (GObject     *object,
       g_object_unref (tmp);
     }
 
-  result = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (concat)));
-  g_object_unref (concat);
-  return result;
+  return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (concat)));
 }
 
 static GListModel *
@@ -310,7 +303,6 @@ object_tree_tree_view_get_children (GObject *object)
   GtkTreeView *treeview = GTK_TREE_VIEW (object);
   GListStore *columns, *selection, *result_list;
   GListModel *props;
-  GtkFlattenListModel *result;
   guint i;
 
   props = list_model_for_properties (object, (const char *[2]) { "model", NULL });
@@ -330,10 +322,8 @@ object_tree_tree_view_get_children (GObject *object)
   g_object_unref (selection);
   g_list_store_append (result_list, columns);
   g_object_unref (columns);
-  result = gtk_flatten_list_model_new (G_LIST_MODEL (result_list));
-  g_object_unref (result_list);
 
-  return G_LIST_MODEL (result);
+  return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (result_list)));
 }
 
 static GListModel *
@@ -341,7 +331,6 @@ object_tree_column_view_get_children (GObject *object)
 {
   GtkColumnView *view = GTK_COLUMN_VIEW (object);
   GListStore *result_list;
-  GtkFlattenListModel *result;
   GListModel *columns, *sublist;
 
   result_list = g_list_store_new (G_TYPE_LIST_MODEL);
@@ -353,10 +342,7 @@ object_tree_column_view_get_children (GObject *object)
   g_list_store_append (result_list, sublist);
   g_object_unref (sublist);
 
-  result = gtk_flatten_list_model_new (G_LIST_MODEL (result_list));
-  g_object_unref (result_list);
-
-  return G_LIST_MODEL (result);
+  return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (result_list)));
 }
 
 static GListModel *
@@ -602,12 +588,11 @@ static GListModel *
 object_get_children (GObject *object)
 {
   GType object_type;
-  GListModel *result, *children;
+  GListModel *children;
   GListStore *result_list;
   guint i;
 
   object_type = G_OBJECT_TYPE (object);
-  result = NULL;
   result_list = NULL;
 
   for (i = 0; i < G_N_ELEMENTS (object_tree_class_funcs); i++)
@@ -619,32 +604,17 @@ object_get_children (GObject *object)
       if (children == NULL)
         continue;
 
-      if (result_list)
-        {
-          g_list_store_append (result_list, children);
-          g_object_unref (children);
-        }
-      else if (result == NULL)
-        {
-          result = children;
-        }
-      else
-        {
-          result_list = g_list_store_new (G_TYPE_LIST_MODEL);
-          g_list_store_append (result_list, result);
-          g_object_unref (result);
-          g_list_store_append (result_list, children);
-          g_object_unref (children);
-        }
+      if (!result_list)
+        result_list = g_list_store_new (G_TYPE_LIST_MODEL);
+
+      g_list_store_append (result_list, children);
+      g_object_unref (children);
     }
 
   if (result_list)
-    {
-      result = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (result_list)));
-      g_object_unref (result_list);
-    }
-
-  return result;
+    return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (result_list)));
+  else
+    return NULL;
 }
 
 static const char *
@@ -1167,7 +1137,6 @@ create_root_model (GdkDisplay *display)
 {
   GtkFilter *custom_filter;
   GtkFilterListModel *filter;
-  GtkFlattenListModel *flatten;
   GListStore *list, *special;
   gpointer item;
 
@@ -1189,9 +1158,7 @@ create_root_model (GdkDisplay *display)
   g_list_store_append (list, filter);
   g_object_unref (filter);
 
-  flatten = gtk_flatten_list_model_new (G_LIST_MODEL (list));
-  g_object_unref (list);
-  return G_LIST_MODEL (flatten);
+  return G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (list)));
 }
 
 static void

testsuite/gtk/filterlistmodel-exhaustive.c

@@ -443,8 +443,6 @@ test_model_changes (gconstpointer model_id)
   g_object_unref (model2);
   g_object_unref (flatten2);
   g_object_unref (flatten1);
-  g_object_unref (store2);
-  g_object_unref (store1);
   g_object_unref (multi);
 }
 

testsuite/gtk/flattenlistmodel.c

@@ -210,7 +210,7 @@ new_model (GListStore *store)
   GtkFlattenListModel *result;
   GString *changes;
 
-  result = gtk_flatten_list_model_new (G_LIST_MODEL (store));
+  result = gtk_flatten_list_model_new (g_object_ref (G_LIST_MODEL (store)));
   changes = g_string_new ("");
   g_object_set_qdata_full (G_OBJECT(result), changes_quark, changes, free_changes);
   g_signal_connect (result, "items-changed", G_CALLBACK (items_changed), changes);

testsuite/gtk/maplistmodel.c

@@ -196,7 +196,7 @@ new_model (GListStore *store)
   GtkMapListModel *result;
   GString *changes;
 
-  result = gtk_map_list_model_new (G_LIST_MODEL (store), map_multiply, GUINT_TO_POINTER (2), NULL);
+  result = gtk_map_list_model_new (g_object_ref (G_LIST_MODEL (store)), map_multiply, GUINT_TO_POINTER (2), NULL);
   changes = g_string_new ("");
   g_object_set_qdata_full (G_OBJECT(result), changes_quark, changes, free_changes);
   g_signal_connect (result, "items-changed", G_CALLBACK (items_changed), changes);

testsuite/gtk/sortlistmodel-exhaustive.c

@@ -433,7 +433,6 @@ test_stability (gconstpointer model_id)
   g_object_unref (sort2);
   g_object_unref (sort1);
   g_object_unref (flatten);
-  g_object_unref (store);
 }
 
 static void