fails:Hash#initialize_copy is private
fails:Hash#initialize_copy replaces the contents of self with other
fails:Hash#initialize_copy tries to convert the passed argument to a hash using #to_hash
fails:Hash#initialize_copy calls to_hash on hash subclasses
fails:Hash#initialize_copy does not transfer default values
fails:Hash#initialize_copy raises a RuntimeError if called on a frozen instance that is modified
fails:Hash#initialize_copy raises a RuntimeError if called on a frozen instance that would not be modified
