public void Load_WithAvailableSources_DoesntSaveThoseSources()
        {
            Source rootFolder = new Source {
                IsRoot = true, SourceType = SourceType.Music, Folder = @"C:\Folder"
            };
            Source specificFolder = new Source {
                IsRoot = false, SourceType = SourceType.Music, Folder = @"C:\Folder\Music"
            };
            IEnumerable <Source> sources = new List <Source> {
                rootFolder, specificFolder
            };

            _sourceService.GetSources(SourceType.Music)
            .Returns(sources);

            // Act
            _viewModel.Load();

            // Assert
            _sourceService.DidNotReceiveWithAnyArgs()
            .Add(null);
        }