Group by: Restore aggregations if removed due to open context

Author: VesnaT

Orange/widgets/data/owgroupby.py

@@ -443,9 +443,14 @@ def set_data(self, data: Table) -> None:
             if data
             else {}
         )
+        default_aggregations = self.aggregations.copy()
 
         self.openContext(self.data)
 
+        # restore aggregations
+        self.aggregations.update({k: v for k, v in default_aggregations.items()
+                                  if k not in self.aggregations})
+
         # update selections in widgets and re-plot
         self.agg_table_model.set_domain(data.domain if data else None)
         self._set_gb_selection()

Orange/widgets/data/tests/test_owgroupby.py

@@ -20,7 +20,7 @@
 from Orange.widgets.tests.base import WidgetTest
 
 
-class TestOWGropBy(WidgetTest):
+class TestOWGroupBy(WidgetTest):
     def setUp(self) -> None:
         self.widget = self.create_widget(OWGroupBy)
         self.iris = Table("iris")
@@ -46,6 +46,14 @@ def test_data(self):
         self.send_signal(self.widget.Inputs.data, None)
         self.assertIsNone(self.get_output(self.widget.Outputs.data))
 
+    def test_data_domain_changed(self):
+        self.send_signal(self.widget.Inputs.data, self.iris[:, -2:])
+        self.assert_aggregations_equal(["Mean", "Concatenate"])
+
+        self.send_signal(self.widget.Inputs.data, self.iris[:, -3:])
+        self.assert_aggregations_equal(["Mean", "Mean", "Concatenate"])
+        self.select_table_rows(self.widget.agg_table_view, [0])
+
     @staticmethod
     def _set_selection(view: QListView, indices: List[int]):
         view.clearSelection()