Add support for Python 3.10 Union syntax

jsons/_lizers_impl.py

@@ -4,6 +4,7 @@
 This module contains functionality for setting and getting serializers and
 deserializers.
 """
+import types
 from typing import Optional, Dict, Sequence, Union
 
 from jsons._cache import cached
@@ -156,4 +157,7 @@ def _get_parents(cls: type, lizers: list) -> list:
  parents.append(cls_)
  except (TypeError, AttributeError):
  pass # Some types do not support `issubclass` (e.g. Union).
+ if not parents and isinstance(naked_cls, types.UnionType) and \
+ Union in lizers:
+ parents = [Union]
  return parents

tests/test_union.py

@@ -86,6 +86,27 @@ def __init__(self, y: int):
  with self.assertRaises(SerializationError):
  jsons.dump(A(1), Union[B], strict=True)
 
+ def test_dump_union_syntax(self):
+ class A:
+ def __init__(self, x: int | float):
+ self.x = x
+
+ dumped = jsons.dump(A(1))
+ expected = {'x': 1}
+ self.assertDictEqual(expected, dumped)
+
+ dumped2 = jsons.dump(A(1), strict=True)
+ expected2 = {'x': 1}
+ self.assertDictEqual(expected2, dumped2)
+
+ dumped = jsons.dump(A(2.0))
+ expected = {'x': 2.0}
+ self.assertDictEqual(expected, dumped)
+
+ dumped2 = jsons.dump(A(2.0), strict=True)
+ expected2 = {'x': 2.0}
+ self.assertDictEqual(expected2, dumped2)
+
  def test_fail(self):
  with self.assertRaises(SerializationError) as err:
  jsons.dump('nope', Union[int, float])
@@ -126,6 +147,18 @@ def __init__(self, x: Union[datetime.datetime, A]):
  with self.assertRaises(DeserializationError):
  jsons.load({'x': 'no match in the union'}, C).x
 
+ def test_load_union_syntax(self):
+ class A:
+ def __init__(self, x: int | float):
+ self.x = x
+
+ self.assertEqual(1, jsons.load({'x': 1}, A).x)
+ self.assertEqual(2.0, jsons.load({'x': 2.0}, A).x)
+
+ # Test Union with invalid value.
+ with self.assertRaises(DeserializationError):
+ jsons.load({'x': 'no match in the union'}, A).x
+
  def test_load_none(self):
  class C:
  def __init__(self, x: int, y: Optional[int]):