[gtkada] Problem calling Gtk.Tree_Store.Reorder at root level

[Damien Carbonne]

Hi all,

I'm having problems with :
   procedure Reorder
     (Tree_Store : access Gtk_Tree_Store_Record;
      Parent     : Gtk_Tree_Iter;
      New_Order  : Gint_Array);
in Gtk.Tree_Store.

I want to reorder root nodes and it fails.
Everything works fine when Reorder is called on a node that is not at 
the root level.

C code for reorder is:
void
gtk_tree_store_reorder (GtkTreeStore *tree_store,
                        GtkTreeIter  *parent,
                        gint         *new_order)
{
  gint i, length = 0;
  GNode *level, *node;
  GtkTreePath *path;
  SortTuple *sort_array;
 
  g_return_if_fail (GTK_IS_TREE_STORE (tree_store));
  g_return_if_fail (!GTK_TREE_STORE_IS_SORTED (tree_store));
  g_return_if_fail (parent == NULL || VALID_ITER (parent, tree_store));
  g_return_if_fail (new_order != NULL);
  ...

So it seems it is possible to call reorder at root level by using NULL 
for parent.
Can you confirm this ?

However, in Ada it is not possible to pass NULL, so I use Null_Iter, but 
C does not accept it and fails on:
  g_return_if_fail (parent == NULL || VALID_ITER (parent, tree_store));

Should not we change the Ada body from:

   procedure Reorder
     (Tree_Store : access Gtk_Tree_Store_Record;
      Parent     : Gtk_Tree_Iter;
      New_Order  : Gint_Array)
   is
      procedure Internal
        (Tree_Store : System.Address;
         Parent     : Gtk_Tree_Iter;
         New_Order  : System.Address);
      pragma Import (C, Internal, "gtk_tree_store_reorder");
   begin
      Internal (Get_Object (Tree_Store), Parent,
                New_Order (New_Order'First)'Address);
   end Reorder;

To something like:
   procedure Reorder
     (Tree_Store : access Gtk_Tree_Store_Record;
      Parent     : Gtk_Tree_Iter;
      New_Order  : Gint_Array)
   is
      procedure Internal
        (Tree_Store : System.Address;
         Parent     : System.Address;
         New_Order  : System.Address);
      pragma Import (C, Internal, "gtk_tree_store_reorder");
   begin
      if Parent = Null_Iter then
         Internal (Get_Object (Tree_Store), System.Null_Address,
                   New_Order (New_Order'First)'Address);
      else
         Internal (Get_Object (Tree_Store), Parent'Address,
                   New_Order (New_Order'First)'Address);
      end if;
   end Reorder;

Best regards,

Damien Carbonne