src/Pure/PIDE/rendering.scala

         val path = Path.explode(text)
         val (dir, base_name) =
           if (text == "" || text.endsWith("/")) (path, "")
           else (path.dir, path.file_name)
 
-        val directory = new JFile(session.resources.append(snapshot.node_name, dir))
+        val directory = new JFile(session.resources.append(snapshot.node_name.master_dir, dir))
         val files = directory.listFiles
         if (files == null) Nil
         else {
           val ignore =
             space_explode(':', options.string("completion_path_ignore")).

         tree1 <- timing_info(tree)
       } yield tree1
   }
 
   def perhaps_append_file(node_name: Document.Node.Name, name: String): String =
-    if (Path.is_valid(name)) session.resources.append(node_name, Path.explode(name)) else name
+    if (Path.is_valid(name)) session.resources.append(node_name.master_dir, Path.explode(name))
+    else name
 
   def tooltips(elements: Markup.Elements, range: Text.Range): Option[Text.Info[List[XML.Tree]]] = {
     val results =
       snapshot.cumulate[Tooltip_Info](range, Tooltip_Info(range), elements, command_states =>
         {