test + userwarning

src/zarr/core/group.py

@@ -4,6 +4,7 @@
 import itertools
 import json
 import logging
+import warnings
 from collections import defaultdict
 from dataclasses import asdict, dataclass, field, fields, replace
 from typing import TYPE_CHECKING, Literal, TypeVar, assert_never, cast, overload
@@ -1170,9 +1171,10 @@ async def _members(
                 # keyerror is raised when `key` names an object (in the object storage sense),
                 # as opposed to a prefix, in the store under the prefix associated with this group
                 # in which case `key` cannot be the name of a sub-array or sub-group.
-                logger.warning(
-                    "Object at %s is not recognized as a component of a Zarr hierarchy.",
-                    key,
+                warnings.warn(
+                    f"Object at {key} is not recognized as a component of a Zarr hierarchy.",
+                    UserWarning,
+                    stacklevel=1,
                 )
 
     def _members_consolidated(

tests/v3/test_group.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import pickle
+import warnings
 from typing import TYPE_CHECKING, Any, Literal, cast
 
 import numpy as np
@@ -1091,8 +1092,8 @@ async def test_require_array(store: Store, zarr_format: ZarrFormat) -> None:
 
 
 @pytest.mark.parametrize("consolidate", [True, False])
-def test_members_name(store: Store, consolidate: bool):
-    group = Group.from_store(store=store)
+async def test_members_name(store: Store, consolidate: bool, zarr_format: ZarrFormat):
+    group = Group.from_store(store=store, zarr_format=zarr_format)
     a = group.create_group(name="a")
     a.create_array("array", shape=(1,))
     b = a.create_group(name="b")
@@ -1108,6 +1109,12 @@ def test_members_name(store: Store, consolidate: bool):
     expected = ["/a", "/a/array", "/a/b", "/a/b/array"]
     assert paths == expected
 
+    # regression test for https://github.com/zarr-developers/zarr-python/pull/2356
+    g = zarr.open_group(store, use_consolidated=False)
+    with warnings.catch_warnings():
+        warnings.simplefilter("error")
+        assert list(g)
+
 
 async def test_open_mutable_mapping():
     group = await zarr.api.asynchronous.open_group(store={}, mode="w")