fix: improve support for date, datetime fields in grids, forms

tests/grids/test_base.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8; -*-
 
+import datetime
 from unittest import TestCase
 from unittest.mock import patch, MagicMock
 
@@ -206,6 +207,31 @@ class TestGrid(WebTestCase):
         self.assertIsNot(grid.renderers['foo'], render2)
         self.assertEqual(grid.renderers['foo'](None, None, None), 42)
 
+    def test_set_default_renderer(self):
+        model = self.app.model
+
+        # no defaults for "plain" schema
+        grid = self.make_grid(columns=['foo', 'bar'])
+        self.assertEqual(grid.renderers, {})
+
+        # no defaults for "plain" mapped class
+        grid = self.make_grid(model_class=model.Setting)
+        self.assertEqual(grid.renderers, {})
+
+        def myrender(obj, key, value):
+            return value
+
+        # renderer set for datetime mapped field
+        grid = self.make_grid(model_class=model.Upgrade)
+        self.assertIn('created', grid.renderers)
+        self.assertIsNot(grid.renderers['created'], myrender)
+
+        # renderer *not* set for datetime, if override present
+        grid = self.make_grid(model_class=model.Upgrade,
+                              renderers={'created': myrender})
+        self.assertIn('created', grid.renderers)
+        self.assertIs(grid.renderers['created'], myrender)
+
     def test_linked_columns(self):
         grid = self.make_grid(columns=['foo', 'bar'])
         self.assertEqual(grid.linked_columns, [])
@@ -1294,6 +1320,18 @@ class TestGrid(WebTestCase):
     # rendering methods
     ##############################
 
+    def test_render_datetime(self):
+        grid = self.make_grid(columns=['foo', 'bar'])
+
+        obj = MagicMock(dt=None)
+        result = grid.render_datetime(obj, 'dt', None)
+        self.assertIsNone(result)
+
+        dt = datetime.datetime(2024, 12, 12, 13, 44, tzinfo=datetime.timezone.utc)
+        obj = MagicMock(dt=dt)
+        result = grid.render_datetime(obj, 'dt', str(dt))
+        self.assertEqual(result, '2024-12-12 13:44+0000')
+
     def test_render_vue_tag(self):
         grid = self.make_grid(columns=['foo', 'bar'])
         html = grid.render_vue_tag()