Feature: group and array name properties (#1940)

* feature: group and array path/name/basename properties

* tests

src/zarr/array.py

@@ -378,6 +378,29 @@ def dtype(self) -> np.dtype[Any]:
     def attrs(self) -> dict[str, JSON]:
         return self.metadata.attributes
 
+    @property
+    def path(self) -> str:
+        """Storage path."""
+        return self.store_path.path
+
+    @property
+    def name(self) -> str | None:
+        """Array name following h5py convention."""
+        if self.path:
+            # follow h5py convention: add leading slash
+            name = self.path
+            if name[0] != "/":
+                name = "/" + name
+            return name
+        return None
+
+    @property
+    def basename(self) -> str | None:
+        """Final component of name."""
+        if self.name is not None:
+            return self.name.split("/")[-1]
+        return None
+
     async def _get_selection(
         self,
         indexer: Indexer,
@@ -630,6 +653,21 @@ def dtype(self) -> np.dtype[Any]:
     def attrs(self) -> Attributes:
         return Attributes(self)
 
+    @property
+    def path(self) -> str:
+        """Storage path."""
+        return self._async_array.path
+
+    @property
+    def name(self) -> str | None:
+        """Array name following h5py convention."""
+        return self._async_array.name
+
+    @property
+    def basename(self) -> str | None:
+        """Final component of name."""
+        return self._async_array.basename
+
     @property
     def metadata(self) -> ArrayMetadata:
         return self._async_array.metadata

src/zarr/group.py

@@ -270,6 +270,27 @@ async def _save_metadata(self) -> None:
         awaitables = [set_or_delete(self.store_path / key, value) for key, value in to_save.items()]
         await asyncio.gather(*awaitables)
 
+    @property
+    def path(self) -> str:
+        """Storage path."""
+        return self.store_path.path
+
+    @property
+    def name(self) -> str:
+        """Group name following h5py convention."""
+        if self.path:
+            # follow h5py convention: add leading slash
+            name = self.path
+            if name[0] != "/":
+                name = "/" + name
+            return name
+        return "/"
+
+    @property
+    def basename(self) -> str:
+        """Final component of name."""
+        return self.name.split("/")[-1]
+
     @property
     def attrs(self) -> dict[str, Any]:
         return self.metadata.attributes
@@ -462,13 +483,15 @@ def create(
         store: StoreLike,
         *,
         attributes: dict[str, Any] = {},  # noqa: B006, FIXME
+        zarr_format: ZarrFormat = 3,
         exists_ok: bool = False,
     ) -> Group:
         obj = sync(
             AsyncGroup.create(
                 store,
                 attributes=attributes,
                 exists_ok=exists_ok,
+                zarr_format=zarr_format,
             ),
         )
 
@@ -521,6 +544,21 @@ def store_path(self) -> StorePath:
     def metadata(self) -> GroupMetadata:
         return self._async_group.metadata
 
+    @property
+    def path(self) -> str:
+        """Storage path."""
+        return self._async_group.path
+
+    @property
+    def name(self) -> str:
+        """Group name following h5py convention."""
+        return self._async_group.name
+
+    @property
+    def basename(self) -> str:
+        """Final component of name."""
+        return self._async_group.basename
+
     @property
     def attrs(self) -> Attributes:
         return Attributes(self)

tests/v3/test_array.py

@@ -0,0 +1,36 @@
+import pytest
+
+from zarr.array import Array
+from zarr.common import ZarrFormat
+from zarr.group import Group
+from zarr.store import LocalStore, MemoryStore
+
+
+@pytest.mark.parametrize("store", ("local", "memory"), indirect=["store"])
+@pytest.mark.parametrize("zarr_format", (2, 3))
+def test_array_name_properties_no_group(
+    store: LocalStore | MemoryStore, zarr_format: ZarrFormat
+) -> None:
+    arr = Array.create(store=store, shape=(100,), chunks=(10,), zarr_format=zarr_format, dtype="i4")
+    assert arr.path == ""
+    assert arr.name is None
+    assert arr.basename is None
+
+
+@pytest.mark.parametrize("store", ("local", "memory"), indirect=["store"])
+@pytest.mark.parametrize("zarr_format", (2, 3))
+def test_array_name_properties_with_group(
+    store: LocalStore | MemoryStore, zarr_format: ZarrFormat
+) -> None:
+    root = Group.create(store=store, zarr_format=zarr_format)
+    foo = root.create_array("foo", shape=(100,), chunks=(10,), dtype="i4")
+    assert foo.path == "foo"
+    assert foo.name == "/foo"
+    assert foo.basename == "foo"
+
+    bar = root.create_group("bar")
+    spam = bar.create_array("spam", shape=(100,), chunks=(10,), dtype="i4")
+
+    assert spam.path == "bar/spam"
+    assert spam.name == "/bar/spam"
+    assert spam.basename == "spam"

tests/v3/test_group.py

@@ -372,3 +372,22 @@ def test_group_init(store: LocalStore | MemoryStore, zarr_format: ZarrFormat) ->
     agroup = sync(AsyncGroup.create(store=store, zarr_format=zarr_format))
     group = Group(agroup)
     assert group._async_group == agroup
+
+
+@pytest.mark.parametrize("store", ("local", "memory"), indirect=["store"])
+@pytest.mark.parametrize("zarr_format", (2, 3))
+def test_group_name_properties(store: LocalStore | MemoryStore, zarr_format: ZarrFormat) -> None:
+    root = Group.create(store=store, zarr_format=zarr_format)
+    assert root.path == ""
+    assert root.name == "/"
+    assert root.basename == ""
+
+    foo = root.create_group("foo")
+    assert foo.path == "foo"
+    assert foo.name == "/foo"
+    assert foo.basename == "foo"
+
+    bar = root.create_group("foo/bar")
+    assert bar.path == "foo/bar"
+    assert bar.name == "/foo/bar"
+    assert bar.basename == "bar"