Does it make sense to provide non-const reference getter

Question

Sometimes I need to expose some of the class members. For example in the following example class Mechanic may need direct access to Engine componen

Answer 1

As I happened to get educated on recently, getters and setters smell of bad design. But, if you want it that way, providing functions to get and set m_engine (Defined by you) rather than just exposing it (You have no intervention) means that you have a plug-in point for future changes.