fix group.create_hierarchy to properly prefix keys with the name of the group

Author: d-v-b

src/zarr/core/group.py

@@ -1414,9 +1414,11 @@ async def create_hierarchy(
 
         Returns
         -------
-            An asynchronous iterator over the created arrays and / or groups.
+            An asynchronous iterator of (str, AsyncArray | AsyncGroup) pairs.
         """
         # check that all the nodes have the same zarr_format as Self
+        prefix = self.path
+        nodes_parsed = {}
         for key, value in nodes.items():
             if value.zarr_format != self.metadata.zarr_format:
                 msg = (
@@ -1433,15 +1435,19 @@ async def create_hierarchy(
                     "create_rooted_hierarchy to create a rooted hierarchy."
                 )
                 raise ValueError(msg)
-
-        nodes_rooted = nodes
+            else:
+                nodes_parsed[_join_paths([prefix, key])] = value
 
         async for key, node in create_hierarchy(
             store=self.store,
-            nodes=nodes_rooted,
+            nodes=nodes_parsed,
             overwrite=overwrite,
         ):
-            yield key, node
+            if prefix == "":
+                out_key = key
+            else:
+                out_key = key.removeprefix(prefix + "/")
+            yield out_key, node
 
     async def keys(self) -> AsyncGenerator[str, None]:
         """Iterate over member names."""

tests/test_group.py

@@ -1645,17 +1645,24 @@ async def test_create_hierarchy_existing_nodes(
 
 @pytest.mark.parametrize("store", ["memory"], indirect=True)
 @pytest.mark.parametrize("overwrite", [True, False])
+@pytest.mark.parametrize("group_path", ["", "foo"])
 @pytest.mark.parametrize("impl", ["async", "sync"])
 async def test_group_create_hierarchy(
-    store: Store, zarr_format: ZarrFormat, overwrite: bool, impl: Literal["async", "sync"]
+    store: Store,
+    zarr_format: ZarrFormat,
+    overwrite: bool,
+    group_path: str,
+    impl: Literal["async", "sync"],
 ) -> None:
     """
     Test that the Group.create_hierarchy method creates specified nodes and returns them in a dict.
     Also test that off-target nodes are not deleted, and that the root group is not deleted
     """
     root_attrs = {"root": True}
-    g = Group.from_store(store, zarr_format=zarr_format, attributes=root_attrs)
-
+    g = sync_group.create_rooted_hierarchy(
+        store=store,
+        nodes={group_path: GroupMetadata(zarr_format=zarr_format, attributes=root_attrs)},
+    )
     node_spec = {
         "a": GroupMetadata(zarr_format=zarr_format, attributes={"name": "a"}),
         "a/b": GroupMetadata(zarr_format=zarr_format, attributes={"name": "a/b"}),
@@ -1689,7 +1696,10 @@ async def test_group_create_hierarchy(
         else:
             assert all_members[k].metadata == v == extant_created[k].metadata
     # ensure that we left the root group as-is
-    assert sync_group.get_node(store=store, path="", zarr_format=zarr_format).attrs == root_attrs
+    assert (
+        sync_group.get_node(store=store, path=group_path, zarr_format=zarr_format).attrs.asdict()
+        == root_attrs
+    )
 
 
 @pytest.mark.parametrize("store", ["memory"], indirect=True)