public void TestShowLibrary_NodeAlreadyInVisibleNodes_VisibleNodesCleared() { _nodeSelectorViewModel.VisibleNodesList.Add(_nodeMoq1.Object); var libraryMoq = new Mock <NodePaletteLibrary>(""); libraryMoq.SetupGet(l => l.Nodes).Returns(new List <Node>()); _nodeSelectorViewModel.ShowLibrary(libraryMoq.Object); Assert.IsTrue(_nodeSelectorViewModel.VisibleNodesList.IsNullOrEmpty()); }