fix: fix safe_issubclass for NewType

pyproject.toml

@@ -166,6 +166,7 @@ ignore = [
 
 [tool.ruff.lint.per-file-ignores]
 "tests/*.py" = ["D", "S", "E501"]
+"tests/test_util.py" = ["D", "S", "E501", "UP006"]
 "docs/*.py" = ["B"]
 "docs/examples/*.py" = ["D", "B", "E501"]
 "src/magicgui/widgets/_image/*.py" = ["D"]

src/magicgui/_util.py

@@ -187,6 +187,8 @@ def _safe_isinstance_tuple(obj: object, superclass: object) -> bool:
 
 def safe_issubclass(obj: object, superclass: object) -> bool:
     """Safely check if obj is a subclass of superclass."""
+    if obj == superclass:
+        return True
     if isinstance(superclass, tuple):
         return any(safe_issubclass(obj, s) for s in superclass)
     obj_origin = get_origin(obj)

tests/test_util.py

@@ -80,3 +80,12 @@ def test_subclass_future(self):
         assert safe_issubclass(Future[list[int]], Future[list])
         assert safe_issubclass(Future[list[int]], Future[list[int]])
         assert not safe_issubclass(Future[list[int]], Future[list[str]])
+
+    def test_subclass_new_type(self):
+        new_int = typing.NewType("new_int", int)
+
+        assert safe_issubclass(new_int, new_int)
+        assert safe_issubclass(list[new_int], typing.List[new_int])
+        assert safe_issubclass(typing.List[new_int], list[new_int])
+        assert safe_issubclass(list[new_int], typing.Sequence[new_int])
+        assert safe_issubclass(list[new_int], list[new_int])