src/Pure/Build/build_job.scala

                   }
                 }
                 def export_text(name: String, text: String, compress: Boolean = true): Unit =
                   export_(name, List(XML.Text(text)), compress = compress)
 
-                for (command <- snapshot.snippet_command) {
+                for (command <- snapshot.snippet_commands) {
                   export_text(Export.DOCUMENT_ID, command.id.toString, compress = false)
                 }
 
                 export_text(Export.FILES,
                   cat_lines(snapshot.node_files.map(name => File.symbolic_path(name.path))),