Add test for validating workspace groups

Re #32125

Framework/PythonInterface/plugins/algorithms/WorkflowAlgorithms/ReflectometryISISPreprocess.py

@@ -5,7 +5,7 @@
 #   Institut Laue - Langevin & CSNS, Institute of High Energy Physics, CAS
 # SPDX - License - Identifier: GPL - 3.0 +
 
-from mantid.api import (AlgorithmFactory, DataProcessorAlgorithm, MatrixWorkspaceProperty, WorkspaceGroup)
+from mantid.api import (AlgorithmFactory, DataProcessorAlgorithm, MatrixWorkspaceProperty, MatrixWorkspace, WorkspaceGroup)
 from mantid.kernel import (CompositeValidator, StringArrayLengthValidator, StringArrayMandatoryValidator,
                            StringArrayProperty, Direction)
 from mantid.simpleapi import LoadEventNexus, LoadNexus
@@ -61,12 +61,15 @@ class ReflectometryISISPreprocess(DataProcessorAlgorithm):
         workspace = self._loadRun(self.getPropertyValue(self._RUNS))
         self.setProperty(self._OUTPUT_WS, workspace)
 
-    def _loadRun(self, run):
+    def _loadRun(self, run: str) -> MatrixWorkspace:
         """Load a run as an event workspace if slicing is requested, or a histogram
         workspace otherwise. Transmission runs are always loaded as histogram workspaces."""
         event_mode = self.getProperty(self._EVENT_MODE).value
         if event_mode:
-            ws = LoadEventNexus(Filename=run, LoadMonitors=True, StoreInADS=False).OutputWorkspace
+            alg = LoadEventNexus(Filename=run, LoadMonitors=True, StoreInADS=False)
+            ws = alg.OutputWorkspace
+            # TODO
+            # monitors = alg.MonitorWorkspace
             self._validate_event_ws(ws)
             self.log().information('Loaded event workspace')
         else:

Framework/PythonInterface/test/python/plugins/algorithms/WorkflowAlgorithms/ReflectometryISISPreprocessTest.py

@@ -7,7 +7,7 @@
 import unittest
 from unittest import mock
 
-from mantid.api import IEventWorkspace, MatrixWorkspace
+from mantid.api import IEventWorkspace, MatrixWorkspace, WorkspaceGroup
 from mantid.simpleapi import CreateSampleWorkspace, ReflectometryISISPreprocess
 
 
@@ -45,6 +45,17 @@ class ReflectometryISISPreprocessTest(unittest.TestCase):
         with self.assertRaisesRegex(RuntimeError, "proton_charge"):
             ReflectometryISISPreprocess(**args)
 
+    @mock.patch("ReflectometryISISPreprocess.LoadEventNexus")
+    def test_validation_of_event_workspace_group_throws(self, mocked_loader):
+        args = {'InputRunList': '13460',
+                "EventMode": True,
+                "OutputWorkspace": "ws"}
+
+        ws = WorkspaceGroup()
+        mocked_loader.return_value.OutputWorkspace = ws
+        with self.assertRaisesRegex(RuntimeError, "Workspace Groups"):
+            ReflectometryISISPreprocess(**args)
+
 
 if __name__ == '__main__':
     unittest.main()