public NuspecVersionCoordinator(INuspecFinder nuspecFinder,
                                 INuspecUtilFactory nuspecUtilFactory)
 {
     _nuspecFinder      = nuspecFinder ?? throw new ArgumentNullException(nameof(nuspecFinder));
     _nuspecUtilFactory = nuspecUtilFactory ?? throw new ArgumentNullException(nameof(nuspecUtilFactory));
 }
 private INuspecVersionCoordinator Create(INuspecFinder finder       = null,
                                          INuspecUtilFactory factory = null)
 {
     return(new NuspecVersionCoordinator(finder ?? Substitute.For <INuspecFinder>(),
                                         factory ?? Substitute.For <INuspecUtilFactory>()));
 }