[gtk+] treemodelfilter: guard for building already existing levels

[Kristian Rietveld <kristian src gnome org>]

commit 52de413d43c410f0794fe55f9ef5d5deb3562aa4
Author: Kristian Rietveld <kris gtk org>
Date:   Sun Jul 10 16:21:08 2011 +0200

    treemodelfilter: guard for building already existing levels

 gtk/gtktreemodelfilter.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtktreemodelfilter.c b/gtk/gtktreemodelfilter.c
index 67a4ee8..69d2f45 100644
--- a/gtk/gtktreemodelfilter.c
+++ b/gtk/gtktreemodelfilter.c
@@ -526,6 +526,12 @@ gtk_tree_model_filter_build_level (GtkTreeModelFilter *filter,
 
   g_assert (filter->priv->child_model != NULL);
 
+  /* Avoid building a level that already exists */
+  if (parent_level)
+    g_assert (g_array_index (parent_level->array, FilterElt, parent_elt_index).children == NULL);
+  else
+    g_assert (filter->priv->root == NULL);
+
   if (filter->priv->in_row_deleted)
     return;