public void Test_AddLayer() { string[] filenames = GetShapefileNames(); var fileService = new Mock <IFileDialogService>(); fileService.Setup(s => s.OpenFiles(It.Is <DataSourceType>(t => t == DataSourceType.Vector), out filenames)).Returns(true); var layerService = new LayerService(_context.Object, fileService.Object, _broadcaster.Object, _reprojectingService.Object); layerService.AddLayer(DataSourceType.Vector); _messageService.Verify(s => s.Warn(It.IsAny <string>()), Times.Never); _layerColection.Verify(l => l.Add(It.IsAny <ILayerSource>(), true), Times.AtLeast(filenames.Count())); }