Do not print todo numbers of activated todos.

After performing this command, the CLI will archive the completed
todos. This may cause the numbers to shift, invalidating the todo
numbers that DoCommand just printed before.

lib/DoCommand.py

@@ -41,8 +41,13 @@ class DoCommand(Command):
     def _uncompleted_children(self, p_todo):
         return sorted([t for t in self.todolist.children(p_todo) if not t.is_completed()])
 
-    def _print_list(self, p_todos):
-        self.out("\n".join(pretty_print_list(p_todos, [self.todolist.pp_number()])))
+    def _print_list(self, p_todos, p_print_numbers=True):
+        filters = []
+
+        if p_print_numbers:
+            filters = [self.todolist.pp_number()]
+
+        self.out("\n".join(pretty_print_list(p_todos, filters)))
 
     def _complete_children(self):
             children = self._uncompleted_children(self.todo)
@@ -72,7 +77,7 @@ class DoCommand(Command):
 
         if parents:
             self.out("The following todo item(s) became active:")
-            self._print_list(parents)
+            self._print_list(parents, False)
 
     def execute(self):
         if not super(DoCommand, self).execute():