(fix): ensure zip directory store compares key to prefix correctly (#2758)

* (fix): ensure zip directory store compares key to prefix correctly

* (chore): add test for externally zipped zarr store

* (fix): no need for async test

* (chore): rel note

---------

Co-authored-by: Deepak Cherian <[email protected]>

Author: ilan-gold

changes/2758.bugfix.rst

@@ -0,0 +1 @@
+Fix zip-store path checking for stores with directories listed as files.

src/zarr/storage/_zip.py

@@ -283,7 +283,7 @@ async def list_dir(self, prefix: str) -> AsyncIterator[str]:
                     yield key
         else:
             for key in keys:
-                if key.startswith(prefix + "/") and key != prefix:
+                if key.startswith(prefix + "/") and key.strip("/") != prefix:
                     k = key.removeprefix(prefix + "/").split("/")[0]
                     if k not in seen:
                         seen.add(k)

tests/test_store/test_zip.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import os
+import shutil
 import tempfile
 import zipfile
 from typing import TYPE_CHECKING
@@ -14,6 +15,7 @@
 from zarr.testing.store import StoreTests
 
 if TYPE_CHECKING:
+    from pathlib import Path
     from typing import Any
 
 
@@ -111,3 +113,15 @@ async def test_zip_open_mode_translation(
         kws = {**store_kwargs, "mode": zip_mode}
         store = await self.store_cls.open(**kws)
         assert store.read_only == read_only
+
+    def test_externally_zipped_store(self, tmp_path: Path) -> None:
+        # See: https://github.com/zarr-developers/zarr-python/issues/2757
+        zarr_path = tmp_path / "foo.zarr"
+        root = zarr.open_group(store=zarr_path, mode="w")
+        root.require_group("foo")
+        root["foo"]["bar"] = np.array([1])
+        shutil.make_archive(zarr_path, "zip", zarr_path)
+        zip_path = tmp_path / "foo.zarr.zip"
+        zipped = zarr.open_group(ZipStore(zip_path, mode="r"), mode="r")
+        assert list(zipped.keys()) == list(root.keys())
+        assert list(zipped["foo"].keys()) == list(root["foo"].keys())