Update signature for _arrayfunction.__array__

xarray/namedarray/_typing.py

@@ -211,9 +211,7 @@ def __array_namespace__(self) -> ModuleType: ...
 # NamedArray can most likely use both __array_function__ and __array_namespace__:
 _arrayfunction_or_api = (_arrayfunction, _arrayapi)
 
-duckarray = Union[
-    _arrayfunction[_ShapeType_co, _DType_co], _arrayapi[_ShapeType_co, _DType_co]
-]
+duckarray = Union[_arrayfunction[_ShapeType, _DType], _arrayapi[_ShapeType, _DType]]
 
 # Corresponds to np.typing.NDArray:
 DuckArray = _arrayfunction[Any, np.dtype[_ScalarType_co]]

xarray/tests/test_namedarray.py

@@ -79,6 +79,8 @@ def __array_namespace__(self) -> ModuleType:
 
 
 def check_duck_array_typevar(a: duckarray[Any, _DType]) -> duckarray[Any, _DType]:
+    reveal_type(a)
+
     # Mypy checks a is valid:
     b: duckarray[Any, _DType] = a