package seedu.emeraldo.logic.commands;

public class UndoCommand extends Command {

    public static final String COMMAND_WORD = "undo";

    public UndoCommand(){}
    
    @Override
    public CommandResult execute() {
        // TODO Auto-generated method stub
        return null;
    }

}

@@ -130,16 +130,85 @@
  %22undo%22;
+%0A    public static final String MESSAGE_SUCCESS = %22Undo successful!%22;
 %0A%0A    pu
@@ -225,16 +225,17 @@
 ommand()
+ 
 %7B%7D%0A    %0A
@@ -297,62 +297,67 @@
     
-// TODO Auto-generated method stub%0A        return null
+%0A        %0A        return new CommandResult(MESSAGE_SUCCESS)
 ;%0A  

Add message success template