diff options
| -rw-r--r-- | Lib/dataclasses.py | 25 | ||||
| -rw-r--r-- | Lib/test/test_dataclasses.py | 21 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2022-10-10-19-14-51.gh-issue-98169.DBWIxL.rst | 2 |
3 files changed, 35 insertions, 13 deletions
diff --git a/Lib/dataclasses.py b/Lib/dataclasses.py index f4617b1dbd..7c3285cf44 100644 --- a/Lib/dataclasses.py +++ b/Lib/dataclasses.py @@ -1321,15 +1321,14 @@ def _asdict_inner(obj, dict_factory): # generator (which is not true for namedtuples, handled # above). return type(obj)(_asdict_inner(v, dict_factory) for v in obj) - elif isinstance(obj, dict) and hasattr(type(obj), 'default_factory'): - # obj is a defaultdict, which has a different constructor from - # dict as it requires the default_factory as its first arg. - # https://bugs.python.org/issue35540 - result = type(obj)(getattr(obj, 'default_factory')) - for k, v in obj.items(): - result[_asdict_inner(k, dict_factory)] = _asdict_inner(v, dict_factory) - return result elif isinstance(obj, dict): + if hasattr(type(obj), 'default_factory'): + # obj is a defaultdict, which has a different constructor from + # dict as it requires the default_factory as its first arg. + result = type(obj)(getattr(obj, 'default_factory')) + for k, v in obj.items(): + result[_asdict_inner(k, dict_factory)] = _asdict_inner(v, dict_factory) + return result return type(obj)((_asdict_inner(k, dict_factory), _asdict_inner(v, dict_factory)) for k, v in obj.items()) @@ -1382,7 +1381,15 @@ def _astuple_inner(obj, tuple_factory): # above). return type(obj)(_astuple_inner(v, tuple_factory) for v in obj) elif isinstance(obj, dict): - return type(obj)((_astuple_inner(k, tuple_factory), _astuple_inner(v, tuple_factory)) + obj_type = type(obj) + if hasattr(obj_type, 'default_factory'): + # obj is a defaultdict, which has a different constructor from + # dict as it requires the default_factory as its first arg. + result = obj_type(getattr(obj, 'default_factory')) + for k, v in obj.items(): + result[_astuple_inner(k, tuple_factory)] = _astuple_inner(v, tuple_factory) + return result + return obj_type((_astuple_inner(k, tuple_factory), _astuple_inner(v, tuple_factory)) for k, v in obj.items()) else: return copy.deepcopy(obj) diff --git a/Lib/test/test_dataclasses.py b/Lib/test/test_dataclasses.py index 76bed0c331..46d4e0feda 100644 --- a/Lib/test/test_dataclasses.py +++ b/Lib/test/test_dataclasses.py @@ -1706,19 +1706,17 @@ class TestCase(unittest.TestCase): def test_helper_asdict_defaultdict(self): # Ensure asdict() does not throw exceptions when a # defaultdict is a member of a dataclass - @dataclass class C: mp: DefaultDict[str, List] - dd = defaultdict(list) dd["x"].append(12) c = C(mp=dd) d = asdict(c) - assert d == {"mp": {"x": [12]}} - assert d["mp"] is not c.mp # make sure defaultdict is copied + self.assertEqual(d, {"mp": {"x": [12]}}) + self.assertTrue(d["mp"] is not c.mp) # make sure defaultdict is copied def test_helper_astuple(self): # Basic tests for astuple(), it should return a new tuple. @@ -1847,6 +1845,21 @@ class TestCase(unittest.TestCase): t = astuple(c, tuple_factory=list) self.assertEqual(t, ['outer', T(1, ['inner', T(11, 12, 13)], 2)]) + def test_helper_astuple_defaultdict(self): + # Ensure astuple() does not throw exceptions when a + # defaultdict is a member of a dataclass + @dataclass + class C: + mp: DefaultDict[str, List] + + dd = defaultdict(list) + dd["x"].append(12) + c = C(mp=dd) + t = astuple(c) + + self.assertEqual(t, ({"x": [12]},)) + self.assertTrue(t[0] is not dd) # make sure defaultdict is copied + def test_dynamic_class_creation(self): cls_dict = {'__annotations__': {'x': int, 'y': int}, } diff --git a/Misc/NEWS.d/next/Library/2022-10-10-19-14-51.gh-issue-98169.DBWIxL.rst b/Misc/NEWS.d/next/Library/2022-10-10-19-14-51.gh-issue-98169.DBWIxL.rst new file mode 100644 index 0000000000..24c3aeecc8 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2022-10-10-19-14-51.gh-issue-98169.DBWIxL.rst @@ -0,0 +1,2 @@ +Fix :func:`dataclasses.astuple` crash when :class:`collections.defaultdict` +is present in the attributes. |