fix __array__

Author: brokkoli71

src/zarr/core/array.py

@@ -2218,8 +2218,10 @@ def __array__(
             raise ValueError(msg)
 
         arr_np = self[...]
+        if self.ndim==0:
+            arr_np = np.array(arr_np)
 
-        if dtype is not None and hasattr(arr_np, "astype"):
+        if dtype is not None:
             arr_np = arr_np.astype(dtype)
 
         return arr_np

src/zarr/core/buffer/core.py

@@ -138,8 +138,9 @@ def __setitem__(self, key: slice, value: Any) -> None:
             raise IndexError("Invalid index for scalar")
         self._value = value
 
-    def __array__(self) -> npt.NDArray[Any]:
-        return np.array(self._value)
+    def __array__(self, dtype: npt.DTypeLike | None = None, copy: bool | None = None
+) -> npt.NDArray[Any]:
+        return np.array(self._value, dtype=dtype, copy=copy)
 
     def reshape(
         self, shape: tuple[int, ...] | Literal[-1], *, order: Literal["A", "C", "F"] = "C"