[gtk/wip/otte/listmodels: 7/17] propertylookuplistmodel: Add ::item-type and ::n-items

[Benjamin Otte <otte src gnome org>]

commit 8b7364966e67b3e78e9de0e1e9ba9454a6f7471f
Author: Benjamin Otte <otte redhat com>
Date:   Sat Jun 11 04:52:34 2022 +0200

    propertylookuplistmodel: Add ::item-type and ::n-items
    
    With tests!

 gtk/gtkpropertylookuplistmodel.c        | 23 ++++++++++++++++++++++-
 testsuite/gtk/propertylookuplistmodel.c | 19 ++++++++++++++-----
 2 files changed, 36 insertions(+), 6 deletions(-)
---
diff --git a/gtk/gtkpropertylookuplistmodel.c b/gtk/gtkpropertylookuplistmodel.c
index 3d5038d87a..ed28116c8d 100644
--- a/gtk/gtkpropertylookuplistmodel.c
+++ b/gtk/gtkpropertylookuplistmodel.c
@@ -39,6 +39,7 @@
 enum {
   PROP_0,
   PROP_ITEM_TYPE,
+  PROP_N_ITEMS,
   PROP_OBJECT,
   PROP_PROPERTY,
   NUM_PROPERTIES
@@ -184,6 +185,8 @@ gtk_property_lookup_list_model_notify_cb (GObject                    *object,
 
   if (removed > 0 || added > 0)
     g_list_model_items_changed (G_LIST_MODEL (self), position, removed, added);
+  if (removed != added)
+    g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_N_ITEMS]);
 }
 
 static guint
@@ -318,6 +321,10 @@ gtk_property_lookup_list_model_get_property (GObject     *object,
       g_value_set_gtype (value, self->item_type);
       break;
 
+    case PROP_N_ITEMS:
+      g_value_set_uint (value, gtk_property_lookup_list_model_get_n_items (G_LIST_MODEL (self)));
+      break;
+
     case PROP_OBJECT:
       g_value_set_object (value, gtk_property_lookup_list_model_get_object (self));
       break;
@@ -366,13 +373,25 @@ gtk_property_lookup_list_model_class_init (GtkPropertyLookupListModelClass *klas
   /**
    * GtkPropertyLookupListModel:item-type:
    *
-   * The `GType` for elements of this object
+   * The `GType` for elements of this object. See [func@Gio.ListModel.get_item_type].
    */
   properties[PROP_ITEM_TYPE] =
       g_param_spec_gtype ("item-type", NULL, NULL,
                           G_TYPE_OBJECT,
                           GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_EXPLICIT_NOTIFY);
 
+  /**
+   * GtkPropertyLookupListModel:n-items:
+   *
+   * The number of items. See [func@Gio.ListModel.get_n_items].
+   *
+   * Since: 4.8
+   **/
+  properties[PROP_N_ITEMS] =
+    g_param_spec_uint ("n-items", NULL, NULL,
+                       0, G_MAXUINT, 0,
+                       G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
   /**
    * GtkPropertyLookupListModel:property:
    *
@@ -456,6 +475,8 @@ gtk_property_lookup_list_model_set_object (GtkPropertyLookupListModel *self,
   g_assert (removed != 0 || added != 0);
 
   g_list_model_items_changed (G_LIST_MODEL (self), 0, removed, added);
+  if (removed != added)
+    g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_N_ITEMS]);
 }
 
 gpointer
diff --git a/testsuite/gtk/propertylookuplistmodel.c b/testsuite/gtk/propertylookuplistmodel.c
index df0f78a415..ea83357bf8 100644
--- a/testsuite/gtk/propertylookuplistmodel.c
+++ b/testsuite/gtk/propertylookuplistmodel.c
@@ -90,6 +90,14 @@ items_changed (GListModel *model,
     }
 }
 
+static void
+notify_n_items (GObject    *object,
+                GParamSpec *pspec,
+                GString    *changes)
+{
+  g_string_append_c (changes, '*');
+}
+
 static void
 free_changes (gpointer data)
 {
@@ -145,6 +153,7 @@ new_model (gboolean fill)
   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);
+  g_signal_connect (result, "notify::n-items", G_CALLBACK (notify_n_items), changes);
 
   return result;
 }
@@ -185,14 +194,14 @@ test_set_object (void)
   model = new_model (FALSE);
   gtk_property_lookup_list_model_set_object (model, widget);
   assert_model (model, "GtkLabel GtkGrid GtkBox GtkWindow");
-  assert_changes (model, "+0");
+  assert_changes (model, "+0*");
   g_object_unref (model);
 
   model = new_model (FALSE);
   assert_model (model, "");
   gtk_property_lookup_list_model_set_object (model, widget);
   assert_model (model, "GtkLabel GtkGrid GtkBox GtkWindow");
-  assert_changes (model, "0+4");
+  assert_changes (model, "0+4*");
   g_object_unref (model);
 
   destroy_widgets ();
@@ -212,15 +221,15 @@ test_change_property (void)
   assert_model (model, ""); /* make sure the model has a definite size */
   gtk_property_lookup_list_model_set_object (model, widget);
   assert_model (model, "GtkLabel GtkGrid GtkBox GtkWindow");
-  assert_changes (model, "0+4");
+  assert_changes (model, "0+4*");
 
   gtk_grid_remove (GTK_GRID (parent), widget);
   assert_model (model, "GtkLabel");
-  assert_changes (model, "1-3");
+  assert_changes (model, "1-3*");
 
   gtk_box_append (GTK_BOX (grandparent), widget);
   assert_model (model, "GtkLabel GtkBox GtkWindow");
-  assert_changes (model, "1+2");
+  assert_changes (model, "1+2*");
 
   g_object_unref (model);
   destroy_widgets ();