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 check_duck_array_typevar(a: duckarray[Any, _DType]) -> duckarray[Any, _DType]:
+    reveal_type(a)
+
     # Mypy checks a is valid:
     b: duckarray[Any, _DType] = a
 
@@ -341,7 +343,7 @@
     def test_duck_array_class(self) -> None:
         numpy_a: NDArray[np.int64]
         numpy_a = np.array([2.1, 4], dtype=np.dtype(np.int64))
         check_duck_array_typevar(numpy_a)
 
         masked_a: np.ma.MaskedArray[Any, np.dtype[np.int64]]
         masked_a = np.ma.asarray([2.1, 4], dtype=np.dtype(np.int64))  # type: ignore[no-untyped-call]
@@ -358,7 +360,7 @@
         # TODO: nxp doesn't use dtype typevars, so can only use Any for the moment:
         arrayapi_a: duckarray[Any, Any]  #  duckarray[Any, np.dtype[np.int64]]
         arrayapi_a = nxp.asarray([2.1, 4], dtype=nxp.int64)
         check_duck_array_typevar(arrayapi_a)
 
     def test_new_namedarray(self) -> None:
         dtype_float = np.dtype(np.float32)