fixups

Author: jhamman

src/zarr/core/array.py

@@ -2385,8 +2385,18 @@ def chunks_initialized(array: Array | AsyncArray) -> tuple[str, ...]:
 def _build_parents(node: AsyncArray | AsyncGroup) -> list[AsyncGroup]:
     from zarr.core.group import AsyncGroup, GroupMetadata
 
-    required_parts = node.store_path.path.split("/")[:-1]
-    parents = []
+    print("path", node.store_path.path)
+
+    if "/" in node.store_path.path:
+        required_parts = node.store_path.path.split("/")[:-1]
+    else:
+        required_parts = []
+    parents = [
+        AsyncGroup(
+            metadata=GroupMetadata(zarr_format=node.metadata.zarr_format),
+            store_path=StorePath(store=node.store_path.store, path=""),
+        )
+    ]
 
     for i, part in enumerate(required_parts):
         path = "/".join(required_parts[:i] + [part])

src/zarr/core/group.py

@@ -700,6 +700,10 @@ async def _members(
                     "Object at %s is not recognized as a component of a Zarr hierarchy.", key
                 )
 
+    async def keys(self) -> AsyncGenerator[str, None]:
+        async for key, _ in self.members():
+            yield key
+
     async def contains(self, member: str) -> bool:
         # TODO: this can be made more efficient.
         try:
@@ -823,10 +827,10 @@ def __delitem__(self, key: str) -> None:
         self._sync(self._async_group.delitem(key))
 
     def __iter__(self) -> Iterator[str]:
-        raise NotImplementedError
+        yield from self.keys()
 
     def __len__(self) -> int:
-        raise NotImplementedError
+        return self.nmembers()
 
     def __setitem__(self, key: str, value: Any) -> None:
         """__setitem__ is not supported in v3"""
@@ -906,6 +910,9 @@ def members(self, max_depth: int | None = 0) -> tuple[tuple[str, Array | Group],
 
         return tuple((kv[0], _parse_async_node(kv[1])) for kv in _members)
 
+    def keys(self) -> Generator[str, None]:
+        yield from self._sync_iter(self._async_group.keys())
+
     def __contains__(self, member: str) -> bool:
         return self._sync(self._async_group.contains(member))
 

src/zarr/storage/logging.py

@@ -150,9 +150,9 @@ async def set(self, key: str, value: Buffer) -> None:
         with self.log():
             return await self._store.set(key=key, value=value)
 
-    async def set_if_not_exists(self, key: str, default: Buffer) -> None:
+    async def set_if_not_exists(self, key: str, value: Buffer) -> None:
         with self.log():
-            return await self._store.set_if_not_exists(key=key, value=default)
+            return await self._store.set_if_not_exists(key=key, value=value)
 
     async def delete(self, key: str) -> None:
         with self.log():

src/zarr/storage/memory.py

@@ -101,10 +101,10 @@ async def set(self, key: str, value: Buffer, byte_range: tuple[int, int] | None
         else:
             self._store_dict[key] = value
 
-    async def set_if_not_exists(self, key: str, default: Buffer) -> None:
+    async def set_if_not_exists(self, key: str, value: Buffer) -> None:
         self._check_writable()
         await self._ensure_open()
-        self._store_dict.setdefault(key, default)
+        self._store_dict.setdefault(key, value)
 
     async def delete(self, key: str) -> None:
         self._check_writable()

tests/v3/test_array.py

@@ -92,10 +92,9 @@ async def test_create_creates_parents(
     expected = [f"{part}/{file}" for file in files for part in parts]
 
     if zarr_format == 2:
-        expected.append("a/b/c/d/.zarray")
-        expected.append("a/b/c/d/.zattrs")
+        expected.extend([".zattrs", ".zgroup", "a/b/c/d/.zarray", "a/b/c/d/.zattrs"])
     else:
-        expected.append("a/b/c/d/zarr.json")
+        expected.extend(["zarr.json", "a/b/c/d/zarr.json"])
 
     expected = sorted(expected)
 

tests/v3/test_group.py

@@ -74,10 +74,9 @@ async def test_create_creates_parents(store: Store, zarr_format: ZarrFormat) ->
     expected = [f"{part}/{file}" for file in files for part in parts]
 
     if zarr_format == 2:
-        expected.append("a/b/c/d/.zgroup")
-        expected.append("a/b/c/d/.zattrs")
+        expected.extend([".zgroup", ".zattrs", "a/b/c/d/.zgroup", "a/b/c/d/.zattrs"])
     else:
-        expected.append("a/b/c/d/zarr.json")
+        expected.extend(["zarr.json", "a/b/c/d/zarr.json"])
 
     expected = sorted(expected)
 
@@ -311,8 +310,7 @@ def test_group_iter(store: Store, zarr_format: ZarrFormat) -> None:
     """
 
     group = Group.from_store(store, zarr_format=zarr_format)
-    with pytest.raises(NotImplementedError):
-        list(group)
+    assert list(group) == []
 
 
 def test_group_len(store: Store, zarr_format: ZarrFormat) -> None:
@@ -321,8 +319,7 @@ def test_group_len(store: Store, zarr_format: ZarrFormat) -> None:
     """
 
     group = Group.from_store(store, zarr_format=zarr_format)
-    with pytest.raises(NotImplementedError):
-        len(group)
+    assert len(group) == 0
 
 
 def test_group_setitem(store: Store, zarr_format: ZarrFormat) -> None: