[gnome-builder] project-tree: sort directories before regular files

[Christian Hergert <chergert src gnome org>]

commit 03e7f03ad8294ba5d7b06cffc59565545363da42
Author: Daniel Buch <boogiewasthere gmail com>
Date:   Wed Jan 16 12:02:44 2019 +0100

    project-tree: sort directories before regular files

 src/plugins/project-tree/gbp-project-tree-addin.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)
---
diff --git a/src/plugins/project-tree/gbp-project-tree-addin.c 
b/src/plugins/project-tree/gbp-project-tree-addin.c
index 7c23a996c..2c20dd9a3 100644
--- a/src/plugins/project-tree/gbp-project-tree-addin.c
+++ b/src/plugins/project-tree/gbp-project-tree-addin.c
@@ -359,6 +359,18 @@ node_compare (IdeTreeNode *node,
   g_assert (IDE_IS_TREE_NODE (node));
   g_assert (IDE_IS_TREE_NODE (child));
 
+  /* Child is a directory and *must* be last in line at this point
+   * given that node is a regular file.
+   * Hence break comparation for subsequent ide_tree_node_insert_before() */
+  if (ide_tree_node_get_children_possible (child) &&
+      !ide_tree_node_get_children_possible (node))
+    return 0;
+
+  /* Skip directories if child is a regular file */
+  if (!ide_tree_node_get_children_possible (child) &&
+      ide_tree_node_get_children_possible (node))
+    return 1;
+
   child_name = ide_tree_node_get_display_name (child);
   node_name = ide_tree_node_get_display_name (node);