feat: add basic "delete results" grid tool

this is done synchronously with no progress indicator yet

tests/grids/test_base.py

@@ -254,6 +254,42 @@ class TestGrid(WebTestCase):
         self.assertEqual(len(grid.actions), 1)
         self.assertIsInstance(grid.actions[0], mod.GridAction)
 
+    def test_set_tools(self):
+        grid = self.make_grid()
+        self.assertEqual(grid.tools, {})
+
+        # null
+        grid.set_tools(None)
+        self.assertEqual(grid.tools, {})
+
+        # empty
+        grid.set_tools({})
+        self.assertEqual(grid.tools, {})
+
+        # full dict is replaced
+        grid.tools = {'foo': 'bar'}
+        self.assertEqual(grid.tools, {'foo': 'bar'})
+        grid.set_tools({'bar': 'baz'})
+        self.assertEqual(grid.tools, {'bar': 'baz'})
+
+        # can specify as list of html elements
+        grid.set_tools(['foo', 'bar'])
+        self.assertEqual(len(grid.tools), 2)
+        self.assertEqual(list(grid.tools.values()), ['foo', 'bar'])
+
+    def test_add_tool(self):
+        grid = self.make_grid()
+        self.assertEqual(grid.tools, {})
+
+        # with key
+        grid.add_tool('foo', key='foo')
+        self.assertEqual(grid.tools, {'foo': 'foo'})
+
+        # without key
+        grid.add_tool('bar')
+        self.assertEqual(len(grid.tools), 2)
+        self.assertEqual(list(grid.tools.values()), ['foo', 'bar'])
+
     def test_get_pagesize_options(self):
         grid = self.make_grid()