From b0f4dab8735f692bcfedcf0fa9a25e238a554bab Mon Sep 17 00:00:00 2001 From: "Eric V. Smith" Date: Tue, 20 Aug 2019 01:40:28 -0400 Subject: bpo-37868: Improve is_dataclass for instances. (GH-15325) --- Lib/dataclasses.py | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'Lib/dataclasses.py') diff --git a/Lib/dataclasses.py b/Lib/dataclasses.py index f778a27912..9020c905d1 100644 --- a/Lib/dataclasses.py +++ b/Lib/dataclasses.py @@ -1015,13 +1015,14 @@ def fields(class_or_instance): def _is_dataclass_instance(obj): """Returns True if obj is an instance of a dataclass.""" - return not isinstance(obj, type) and hasattr(obj, _FIELDS) + return hasattr(type(obj), _FIELDS) def is_dataclass(obj): """Returns True if obj is a dataclass or an instance of a dataclass.""" - return hasattr(obj, _FIELDS) + cls = obj if isinstance(obj, type) else type(obj) + return hasattr(cls, _FIELDS) def asdict(obj, *, dict_factory=dict): -- cgit v1.2.1