Ensure Tabulator supports grouping on numeric columns (#2987)

panel/tests/widgets/test_tables.py

@@ -433,6 +433,23 @@ def test_tabulator_groups(document, comm):
     ]
 
 
+def test_tabulator_numeric_groups(document, comm):
+    df = pd.DataFrame(np.random.rand(10, 3))
+    table = Tabulator(df, groups={'Number': [0, 1]})
+
+    model = table.get_root(document, comm)
+
+    assert model.configuration['columns'] == [
+        {'field': 'index'},
+        {'title': 'Number',
+         'columns': [
+            {'field': '0'},
+            {'field': '1'}
+        ]},
+        {'field': '2'}
+    ]
+
+
 def test_tabulator_frozen_cols(document, comm):
     df = makeMixedDataFrame()
     table = Tabulator(df, frozen_columns=['index'])

panel/widgets/tables.py

@@ -1343,9 +1343,13 @@ def _config_columns(self, column_objs):
                     column_objs.remove(cols[0])
         ordered += column_objs
 
+        grouping = {
+            group: [str(gc) for gc in group_cols]
+            for group, group_cols in self.groups.items()
+        }
         for i, column in enumerate(ordered):
             matching_groups = [
-                group for group, group_cols in self.groups.items()
+                group for group, group_cols in grouping.items()
                 if column.field in group_cols
             ]
             col_dict = {'field': column.field}