Renable is not a valid word, Re-enable (or Reenable to some extent) is.

Issues: The prototype of the initial solution is too 'indicative'(uppercase, lowercase,...), and the std::functional in the header gives part of the solution.

Important note: you may have a templated callback there and get the possibility of using a lambda instead of a std:::functional => do not 'extern blabla' declare the solution.
See my solution: the template <typename CallBackType> void function(CallBackType callback) is the canonic way to do it.

Please use the testing framework properly. You should read the kata authoring guide to learn how to create katas