src/Pure/PIDE/editor.scala

     val none: Output = Output(defined = false)
     val init: Output = Output()
   }
 
   sealed case class Output(
+    snapshot: Document.Snapshot = Document.Snapshot.init,
     results: Command.Results = Command.Results.empty,
     messages: List[XML.Elem] = Nil,
     defined: Boolean = true
   )
 }

                     yield msg).partition(Protocol.is_state)
               }
               val (urgent, regular) = other.partition(Protocol.is_urgent)
               urgent ::: (if (output_state()) states else Nil) ::: regular
             }
-            Editor.Output(results = results, messages = messages)
+            Editor.Output(snapshot = snapshot, results = results, messages = messages)
           }
           else Editor.Output.none
       }
     }
   }