protected void given_file_system(string currentDirectory)
            {
                FileSystem = new InMemoryFileSystem
                {
                        CurrentDirectory = currentDirectory
                };
                ServiceLocator.RegisterService<IFileSystem>(FileSystem);

                Environment = new InMemoryEnvironment(FileSystem.GetDirectory(currentDirectory),
                                                      FileSystem.GetDirectory(DefaultInstallationPaths.ConfigurationDirectory));
                ServiceLocator.RegisterService<IEnvironment>(Environment);
            }
 public context_source_dir()
 {
     file_system = new InMemoryFileSystem();
     root = file_system.CreateTempDirectory();
     env = new InMemoryEnvironment(root);
 }