[gnome-builder] tree: add gb_tree_find_item()

[Christian Hergert <chergert src gnome org>]

commit 18da25edfed5c7db1f8d9719e1a7f5fdf0cd1fae
Author: Christian Hergert <christian hergert me>
Date:   Sat Apr 11 14:12:04 2015 -0700

    tree: add gb_tree_find_item()
    
    This is handy if you want to find an item between rebuilds of the tree.

 src/tree/gb-tree.c |   46 ++++++++++++++++++++++++++++++++++++++++++++++
 src/tree/gb-tree.h |    2 ++
 2 files changed, 48 insertions(+), 0 deletions(-)
---
diff --git a/src/tree/gb-tree.c b/src/tree/gb-tree.c
index 85da6ac..c59eda1 100644
--- a/src/tree/gb-tree.c
+++ b/src/tree/gb-tree.c
@@ -1016,6 +1016,52 @@ gb_tree_scroll_to_node (GbTree     *tree,
   gtk_tree_path_free (path);
 }
 
+static gboolean
+gb_tree_find_item_foreach_cb (GtkTreeModel *model,
+                              GtkTreePath  *path,
+                              GtkTreeIter  *iter,
+                              gpointer      data)
+{
+  GbTreeNode *node = NULL;
+  struct {
+    GObject    *item;
+    GbTreeNode *result;
+  } *lookup = data;
+
+  gtk_tree_model_get (model, iter, 0, &node, -1);
+
+  if (node && (lookup->item == gb_tree_node_get_item (node)))
+    {
+      lookup->result = node;
+      return TRUE;
+    }
+
+  return FALSE;
+}
+
+GbTreeNode *
+gb_tree_find_item (GbTree  *self,
+                   GObject *item)
+{
+  GbTreePrivate *priv = gb_tree_get_instance_private (self);
+  struct {
+    GObject    *item;
+    GbTreeNode *result;
+  } lookup;
+
+  g_return_val_if_fail (GB_IS_TREE (self), NULL);
+  g_return_val_if_fail (!item || G_IS_OBJECT (item), NULL);
+
+  lookup.item = item;
+  lookup.result = NULL;
+
+  gtk_tree_model_foreach (GTK_TREE_MODEL (priv->store),
+                          gb_tree_find_item_foreach_cb,
+                          &lookup);
+
+  return lookup.result;
+}
+
 /**
  * gb_tree_finalize:
  * @object: (in): A #GbTree.
diff --git a/src/tree/gb-tree.h b/src/tree/gb-tree.h
index 71a76fb..bdb56b1 100644
--- a/src/tree/gb-tree.h
+++ b/src/tree/gb-tree.h
@@ -78,6 +78,8 @@ GbTree       *gb_tree_node_get_tree  (GbTreeNode    *node);
 void          gb_tree_set_show_icons (GbTree        *tree,
                                       gboolean       show_icons);
 gboolean      gb_tree_get_show_icons (GbTree        *tree);
+GbTreeNode   *gb_tree_find_item      (GbTree        *tree,
+                                      GObject       *item);
 void          gb_tree_scroll_to_node (GbTree        *tree,
                                       GbTreeNode    *node);