Testing Notes

#### Constructor #####
  Ask what you need directly
  
  public X(Config config) {
    user = config.getUser();
    // blah 
    
    y = config.getY();
  }
  
  # Testable
  public X(User user, Y y) {
    this.user = user;
    // blah 
    
    this.y = y;
  }
  
######### Using new constructor within methods ##############