.. _program_listing_file_Testing_Python_SelectionTest.py:

Program Listing for File SelectionTest.py
=========================================

|exhale_lsh| :ref:`Return to documentation for file <file_Testing_Python_SelectionTest.py>` (``Testing/Python/SelectionTest.py``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: py

   from unittest.mock import MagicMock
   
   import slicer
   from slicer import (
       vtkMRMLLayerDMSelectionObserver,
       vtkMRMLScene,
       vtkMRMLLayerDMObjectEventObserverScripted,
       vtkMRMLInteractionNode,
   )
   from slicer.ScriptedLoadableModule import ScriptedLoadableModuleTest
   
   
   class SelectionTest(ScriptedLoadableModuleTest):
       def setUp(self):
           slicer.mrmlScene.Clear(0)
           self.selection_obs = vtkMRMLLayerDMSelectionObserver()
           self.selection_obs.SetScene(slicer.mrmlScene)
           self.mock = MagicMock(return_value=None)
           self._spy = vtkMRMLLayerDMObjectEventObserverScripted()
           self._spy.UpdateObserver(None, self.selection_obs)
           self._spy.SetPythonCallback(self.mock)
   
       def test_has_access_to_singleton_nodes(self):
           assert self.selection_obs.GetInteractionNode() is not None
           assert self.selection_obs.GetSelectionNode() is not None
   
       def test_with_empty_new_scene_doesnt_initialize_singleton_nodes(self):
           scene = vtkMRMLScene()
           obs = vtkMRMLLayerDMSelectionObserver()
           obs.SetScene(scene)
   
           assert obs.GetInteractionNode() is None
           assert obs.GetSelectionNode() is None
   
       def test_helps_in_placing_nodes(self):
           markups_node = slicer.mrmlScene.AddNewNodeByClass("vtkMRMLMarkupsFiducialNode")
           self.selection_obs.StartPlace(markups_node, True)
   
           self.mock.assert_called()
           assert self.selection_obs.GetActivePlaceNodeID() == markups_node.GetID()
           assert self.selection_obs.GetCurrentInteractionMode() == vtkMRMLInteractionNode.Place
           assert self.selection_obs.GetPlaceModePersistence()
           assert self.selection_obs.IsPlacing(markups_node)
           self.mock.reset_mock()
           self.selection_obs.StopPlace()
           self.mock.assert_called()