Remove deprecated Date, Time and Datetime behaviour (#1736)

This PR updates the `Date`, `Time` and `Datetime` trait types for
previous deprecations:

- the `Date` trait type will now no longer accept `datetime` instances
unless `allow_datetime=True` is used
- the `Date`, `Time` and `Datetime` trait types will now no longer
accept a value of `None` unless `allow_none=True` is used

**Checklist**
- [x] Tests
- [x] Update API reference (`docs/source/traits_api_reference`) - no
changes needed
- [x] Update User manual (`docs/source/traits_user_manual`)
- [x] Update type annotation hints in stub files - no changes needed

docs/source/traits_user_manual/defining.rst

@@ -307,11 +307,11 @@ the table.
 | Constant         | Constant(*value*\ [, \*\*\ *metadata*])                  |
 +------------------+----------------------------------------------------------+
 | Date             | Date(*value*\ [, *default_value* = None,                 |
-|                  | *allow_datetime* = None, *allow_none* = None,            |
+|                  | *allow_datetime* = False, *allow_none* = False,          |
 |                  | \*\*\ *metadata*])                                       |
 +------------------+----------------------------------------------------------+
 | Datetime         | Datetime(*value*\ [, *default_value* = None,             |
-|                  | *allow_none* = None, \*\*\ *metadata*])                  |
+|                  | *allow_none* = False, \*\*\ *metadata*])                 |
 +------------------+----------------------------------------------------------+
 | Dict             | Dict([*key_trait* = None, *value_trait* = None,          |
 |                  | *value* = None, *items* = True, \*\*\ *metadata*])       |
@@ -394,7 +394,7 @@ the table.
 | This             | n/a                                                      |
 +------------------+----------------------------------------------------------+
 | Time             | Time(*value*\ [, *default_value* = None,                 |
-|                  | *allow_none* = None, \*\*\ *metadata*])                  |
+|                  | *allow_none* = False, \*\*\ *metadata*])                 |
 +------------------+----------------------------------------------------------+
 | ToolbarButton    | ToolbarButton([*label* = '', *image* = None, *style* =   |
 |                  | 'toolbar', *orientation* = 'vertical', *width_padding* = |

traits/tests/test_date.py

@@ -71,28 +71,22 @@ def test_assign_non_date(self):
         with self.assertRaises(TraitError) as exception_context:
             obj.simple_date = "1975-2-13"
         message = str(exception_context.exception)
-        self.assertIn("must be a date or None, but", message)
+        self.assertIn("must be a non-datetime date, but", message)
 
     def test_assign_none_with_allow_none_not_given(self):
         obj = HasDateTraits(simple_date=UNIX_EPOCH)
-        self.assertIsNotNone(obj.simple_date)
-        with self.assertWarns(DeprecationWarning) as warnings_cm:
+        with self.assertRaises(TraitError) as exception_context:
             obj.simple_date = None
-        self.assertIsNone(obj.simple_date)
-
-        _, _, this_module = __name__.rpartition(".")
-        self.assertIn(this_module, warnings_cm.filename)
-        self.assertIn(
-            "None will no longer be accepted",
-            str(warnings_cm.warning),
-        )
+        self.assertEqual(obj.simple_date, UNIX_EPOCH)
+        message = str(exception_context.exception)
+        self.assertIn("must be a non-datetime date, but", message)
 
     def test_assign_none_with_allow_none_false(self):
         obj = HasDateTraits(none_prohibited=UNIX_EPOCH)
         with self.assertRaises(TraitError) as exception_context:
             obj.none_prohibited = None
         message = str(exception_context.exception)
-        self.assertIn("must be a date, but", message)
+        self.assertIn("must be a non-datetime date, but", message)
 
     def test_assign_none_with_allow_none_true(self):
         obj = HasDateTraits(none_allowed=UNIX_EPOCH)
@@ -106,7 +100,7 @@ def test_assign_datetime_with_allow_datetime_false(self):
         with self.assertRaises(TraitError) as exception_context:
             obj.datetime_prohibited = test_datetime
         message = str(exception_context.exception)
-        self.assertIn("must be a non-datetime date or None, but", message)
+        self.assertIn("must be a non-datetime date, but", message)
 
     def test_assign_datetime_with_allow_datetime_true(self):
         test_datetime = datetime.datetime(1975, 2, 13)
@@ -117,21 +111,14 @@ def test_assign_datetime_with_allow_datetime_true(self):
     def test_assign_datetime_with_allow_datetime_not_given(self):
         # For traits where "allow_datetime" is not specified, a
         # DeprecationWarning should be issued on assignment of datetime.
+        test_date = datetime.date(2023, 1, 11)
         test_datetime = datetime.datetime(1975, 2, 13)
-        obj = HasDateTraits()
-        with self.assertWarns(DeprecationWarning) as warnings_cm:
-            # Note: the warning depends on the type, not the value; this case
-            # should warn even though the time component of the datetime is
-            # zero.
+        obj = HasDateTraits(simple_date=test_date)
+        with self.assertRaises(TraitError) as exception_context:
             obj.simple_date = test_datetime
-        self.assertEqual(obj.simple_date, test_datetime)
-
-        _, _, this_module = __name__.rpartition(".")
-        self.assertIn(this_module, warnings_cm.filename)
-        self.assertIn(
-            "datetime instances will no longer be accepted",
-            str(warnings_cm.warning),
-        )
+        self.assertEqual(obj.simple_date, test_date)
+        message = str(exception_context.exception)
+        self.assertIn("must be a non-datetime date, but", message)
 
     def test_allow_none_false_allow_datetime_false(self):
         obj = HasDateTraits(strict=UNIX_EPOCH)

traits/tests/test_datetime.py

@@ -63,34 +63,29 @@ def test_assign_non_datetime(self):
         with self.assertRaises(TraitError) as exception_context:
             obj.simple_datetime = "2021-02-05 12:00:00"
         message = str(exception_context.exception)
-        self.assertIn("must be a datetime or None, but", message)
+        self.assertIn("must be a datetime, but", message)
 
     def test_assign_date(self):
         obj = HasDatetimeTraits()
         with self.assertRaises(TraitError) as exception_context:
             obj.simple_datetime = datetime.date(1975, 2, 13)
         message = str(exception_context.exception)
-        self.assertIn("must be a datetime or None, but", message)
+        self.assertIn("must be a datetime, but", message)
         self.assertIsNone(obj.simple_datetime)
 
     def test_assign_none_with_allow_none_not_given(self):
         obj = HasDatetimeTraits(simple_datetime=UNIX_EPOCH)
-        self.assertIsNotNone(obj.simple_datetime)
-        with self.assertWarns(DeprecationWarning) as warnings_cm:
+        with self.assertRaises(TraitError) as exception_context:
             obj.simple_datetime = None
-        self.assertIsNone(obj.simple_datetime)
-
-        _, _, this_module = __name__.rpartition(".")
-        self.assertIn(this_module, warnings_cm.filename)
-        self.assertIn(
-            "None will no longer be accepted",
-            str(warnings_cm.warning),
-        )
+        self.assertEqual(obj.simple_datetime, UNIX_EPOCH)
+        message = str(exception_context.exception)
+        self.assertIn("must be a datetime, but", message)
 
     def test_assign_none_with_allow_none_false(self):
         obj = HasDatetimeTraits(none_prohibited=UNIX_EPOCH)
         with self.assertRaises(TraitError) as exception_context:
             obj.none_prohibited = None
+        self.assertEqual(obj.none_prohibited, UNIX_EPOCH)
         message = str(exception_context.exception)
         self.assertIn("must be a datetime, but", message)
 

traits/tests/test_time.py

@@ -63,34 +63,29 @@ def test_assign_non_time(self):
         with self.assertRaises(TraitError) as exception_context:
             obj.simple_time = "12:00:00"
         message = str(exception_context.exception)
-        self.assertIn("must be a time or None, but", message)
+        self.assertIn("must be a time, but", message)
 
     def test_assign_datetime(self):
         obj = HasTimeTraits()
         with self.assertRaises(TraitError) as exception_context:
             obj.simple_time = datetime.datetime(1975, 2, 13)
         message = str(exception_context.exception)
-        self.assertIn("must be a time or None, but", message)
+        self.assertIn("must be a time, but", message)
         self.assertIsNone(obj.simple_time)
 
     def test_assign_none_with_allow_none_not_given(self):
         obj = HasTimeTraits(simple_time=UNIX_EPOCH)
-        self.assertIsNotNone(obj.simple_time)
-        with self.assertWarns(DeprecationWarning) as warnings_cm:
+        with self.assertRaises(TraitError) as exception_context:
             obj.simple_time = None
-        self.assertIsNone(obj.simple_time)
-
-        _, _, this_module = __name__.rpartition(".")
-        self.assertIn(this_module, warnings_cm.filename)
-        self.assertIn(
-            "None will no longer be accepted",
-            str(warnings_cm.warning),
-        )
+        self.assertEqual(obj.simple_time, UNIX_EPOCH)
+        message = str(exception_context.exception)
+        self.assertIn("must be a time, but", message)
 
     def test_assign_none_with_allow_none_false(self):
         obj = HasTimeTraits(none_prohibited=UNIX_EPOCH)
         with self.assertRaises(TraitError) as exception_context:
             obj.none_prohibited = None
+        self.assertEqual(obj.none_prohibited, UNIX_EPOCH)
         message = str(exception_context.exception)
         self.assertIn("must be a time, but", message)