model.datatypes: fix error when copy Dates

basyx/aas/model/datatypes.py

@@ -78,6 +78,17 @@ def __eq__(self, other: object) -> bool:
         other_tzinfo = other.tzinfo if hasattr(other, 'tzinfo') else None  # type: ignore
         return datetime.date.__eq__(self, other) and self.tzinfo == other_tzinfo
 
+    def __copy__(self):
+        cls = self.__class__
+        result = cls.__new__(cls, self.year, self.month, self.day, self.tzinfo)
+        return result
+
+    def __deepcopy__(self, memo):
+        cls = self.__class__
+        result = cls.__new__(cls, self.year, self.month, self.day, self.tzinfo)
+        memo[id(self)] = result
+        return result
+
     # TODO override comparsion operators
     # TODO add into_datetime function
     # TODO add includes(:DateTime) -> bool function

test/model/test_datatypes.py

@@ -7,6 +7,7 @@
 import datetime
 import math
 import unittest
+import copy
 
 import dateutil
 
@@ -177,6 +178,13 @@ def test_parse_partial_dates(self) -> None:
             model.datatypes.from_xsd("10-10", model.datatypes.GYearMonth)
         self.assertEqual("Value is not a valid XSD GYearMonth string", str(cm.exception))
 
+    def test_copy_date(self) -> None:
+        date = model.datatypes.Date(2020, 1, 24)
+        date_copy_shallow = copy.copy(date)
+        self.assertEqual(date, date_copy_shallow)
+        date_copy_deep = copy.deepcopy(date)
+        self.assertEqual(date, date_copy_deep)
+
     def test_serialize_partial_dates(self) -> None:
         self.assertEqual("2019", model.datatypes.xsd_repr(model.datatypes.GYear(2019)))
         self.assertEqual("2019Z", model.datatypes.xsd_repr(model.datatypes.GYear(2019, datetime.timezone.utc)))